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MDM2 inhibitors could treat resistant AML
Preclinical research has revealed a potential treatment for chemotherapy-resistant acute myeloid leukemia (AML).
Researchers characterized a mechanism of chemotherapy resistance in AML and found that MDM2 is a key player in this dysregulated signaling pathway.
They tested MDM2 inhibitors and found these drugs could sensitize resistant AML to chemotherapy in vitro and in vivo.
In fact, mice with refractory AML responded to standard induction therapy when combined with an MDM2 inhibitor, showing no signs of disease and prolonged survival.
These results were published in Cancer Discovery.
“We were blown away when we saw the results,” said study author William Stanford, PhD, of Ottawa Hospital Research Institute in Ontario, Canada.
“If these findings hold up in clinical trials, we could have a new treatment for people who would almost certainly die of their disease today.”
Mechanism of resistance
Dr. Stanford’s research began with the protein MTF2. He and his colleagues previously found that MTF2 plays a role in erythropoiesis, and the team wanted to determine if MTF2 also plays a role in AML.
Using AML samples from patients treated at The Ottawa Hospital, the researchers found the mean survival was three times longer in patients with normal MTF2 activity than in patients with low MTF2 activity.
“Initially, we thought that MTF2 could be an important biomarker to identify patients who might benefit from experimental therapies,” Dr. Stanford said. “But then we started thinking that if we could understand what MTF2 was doing, maybe we could use this information to develop a new treatment.”
Dr. Stanford and his colleagues discovered that MTF2 represses MDM2, a protein that helps cells resist chemotherapy.
The team found that MTF2-deficient cells overexpress MDM2, which inhibits p53, and this leads to defects in cell-cycle regulation and apoptosis that enable resistance to chemotherapy.
Testing MDM2 inhibitors
Since MDM2 inhibitors are already being tested in clinical trials for other cancers, Dr. Stanford and his colleagues tested these inhibitors in vitro and in mouse models of chemotherapy-resistant AML.
The in vitro experiments included two MDM2 inhibitors—Nutlin3A and MI-773—combined with daunorubicin or cytarabine.
The researchers found that refractory, MTF2-deficient AML cells underwent apoptosis when treated with either daunorubicin or cytarabine in combination with Nutlin3A or MI-773. The effect was comparable to that observed in AML cells with normal MTF2.
The team found that Nutlin3A was more efficient at sensitizing refractory, MTF2-deficient AML cells to daunorubicin, so they used Nutlin3A in the in vivo experiments.
For these experiments, the researchers tested Nutlin3A in mice injected with either chemotherapy-responsive AML cells (with normal MTF2) or refractory, MTF2-deficient AML cells.
Once the mice had “a substantial leukemic burden” (≥ 20% CD45+CD33+ leukemic blasts in their peripheral blood), they were randomized to receive vehicle control, Nutlin3A, standard induction therapy, or induction plus Nutlin3A.
The mice engrafted with chemotherapy-responsive AML cells did not respond to vehicle control or Nutlin3A alone. However, they did respond to standard induction and induction plus Nutlin3A, surviving until the end of the experiment at 16 weeks.
Among the mice engrafted with refractory, MTF2-deficient AML cells, only those animals treated with induction plus Nutlin3A survived until the end of the experiment.
The researchers also noted a “dramatic loss” in the blast-containing CD45+CD33+ and CD34+CD38− populations in mice treated with induction plus Nutlin3A.
To assess residual disease, the researchers performed secondary transplants with cells from mice that had engrafted with refractory, MTF2-deficient AML cells but responded to induction plus Nutlin3A.
The recipient mice had no evidence of AML at 16 weeks after transplant when the experiment ended.
Dr. Stanford and his colleagues are now trying to obtain pharmaceutical-grade MDM2 inhibitors to conduct trials in AML patients at The Ottawa Hospital.
The researchers are also screening libraries of approved drugs to see if any of these can block MDM2, and they are working with a biotech company to develop a test to identify chemotherapy-resistant AML patients who would respond to MDM2 inhibitors.
The current research was supported by grants from the Canadian Cancer Society Research Institute, Canadian Institutes of Health Research, Cancer Research Society, National Institutes of Health, and a Tier 1 Canada Research Chair in Integrative Stem Cell Biology. One study author reported a relationship with Epicypher, Inc. No other conflicts of interest were reported.
Preclinical research has revealed a potential treatment for chemotherapy-resistant acute myeloid leukemia (AML).
Researchers characterized a mechanism of chemotherapy resistance in AML and found that MDM2 is a key player in this dysregulated signaling pathway.
They tested MDM2 inhibitors and found these drugs could sensitize resistant AML to chemotherapy in vitro and in vivo.
In fact, mice with refractory AML responded to standard induction therapy when combined with an MDM2 inhibitor, showing no signs of disease and prolonged survival.
These results were published in Cancer Discovery.
“We were blown away when we saw the results,” said study author William Stanford, PhD, of Ottawa Hospital Research Institute in Ontario, Canada.
“If these findings hold up in clinical trials, we could have a new treatment for people who would almost certainly die of their disease today.”
Mechanism of resistance
Dr. Stanford’s research began with the protein MTF2. He and his colleagues previously found that MTF2 plays a role in erythropoiesis, and the team wanted to determine if MTF2 also plays a role in AML.
Using AML samples from patients treated at The Ottawa Hospital, the researchers found the mean survival was three times longer in patients with normal MTF2 activity than in patients with low MTF2 activity.
“Initially, we thought that MTF2 could be an important biomarker to identify patients who might benefit from experimental therapies,” Dr. Stanford said. “But then we started thinking that if we could understand what MTF2 was doing, maybe we could use this information to develop a new treatment.”
Dr. Stanford and his colleagues discovered that MTF2 represses MDM2, a protein that helps cells resist chemotherapy.
The team found that MTF2-deficient cells overexpress MDM2, which inhibits p53, and this leads to defects in cell-cycle regulation and apoptosis that enable resistance to chemotherapy.
Testing MDM2 inhibitors
Since MDM2 inhibitors are already being tested in clinical trials for other cancers, Dr. Stanford and his colleagues tested these inhibitors in vitro and in mouse models of chemotherapy-resistant AML.
The in vitro experiments included two MDM2 inhibitors—Nutlin3A and MI-773—combined with daunorubicin or cytarabine.
The researchers found that refractory, MTF2-deficient AML cells underwent apoptosis when treated with either daunorubicin or cytarabine in combination with Nutlin3A or MI-773. The effect was comparable to that observed in AML cells with normal MTF2.
The team found that Nutlin3A was more efficient at sensitizing refractory, MTF2-deficient AML cells to daunorubicin, so they used Nutlin3A in the in vivo experiments.
For these experiments, the researchers tested Nutlin3A in mice injected with either chemotherapy-responsive AML cells (with normal MTF2) or refractory, MTF2-deficient AML cells.
Once the mice had “a substantial leukemic burden” (≥ 20% CD45+CD33+ leukemic blasts in their peripheral blood), they were randomized to receive vehicle control, Nutlin3A, standard induction therapy, or induction plus Nutlin3A.
The mice engrafted with chemotherapy-responsive AML cells did not respond to vehicle control or Nutlin3A alone. However, they did respond to standard induction and induction plus Nutlin3A, surviving until the end of the experiment at 16 weeks.
Among the mice engrafted with refractory, MTF2-deficient AML cells, only those animals treated with induction plus Nutlin3A survived until the end of the experiment.
The researchers also noted a “dramatic loss” in the blast-containing CD45+CD33+ and CD34+CD38− populations in mice treated with induction plus Nutlin3A.
To assess residual disease, the researchers performed secondary transplants with cells from mice that had engrafted with refractory, MTF2-deficient AML cells but responded to induction plus Nutlin3A.
The recipient mice had no evidence of AML at 16 weeks after transplant when the experiment ended.
Dr. Stanford and his colleagues are now trying to obtain pharmaceutical-grade MDM2 inhibitors to conduct trials in AML patients at The Ottawa Hospital.
The researchers are also screening libraries of approved drugs to see if any of these can block MDM2, and they are working with a biotech company to develop a test to identify chemotherapy-resistant AML patients who would respond to MDM2 inhibitors.
The current research was supported by grants from the Canadian Cancer Society Research Institute, Canadian Institutes of Health Research, Cancer Research Society, National Institutes of Health, and a Tier 1 Canada Research Chair in Integrative Stem Cell Biology. One study author reported a relationship with Epicypher, Inc. No other conflicts of interest were reported.
Preclinical research has revealed a potential treatment for chemotherapy-resistant acute myeloid leukemia (AML).
Researchers characterized a mechanism of chemotherapy resistance in AML and found that MDM2 is a key player in this dysregulated signaling pathway.
They tested MDM2 inhibitors and found these drugs could sensitize resistant AML to chemotherapy in vitro and in vivo.
In fact, mice with refractory AML responded to standard induction therapy when combined with an MDM2 inhibitor, showing no signs of disease and prolonged survival.
These results were published in Cancer Discovery.
“We were blown away when we saw the results,” said study author William Stanford, PhD, of Ottawa Hospital Research Institute in Ontario, Canada.
“If these findings hold up in clinical trials, we could have a new treatment for people who would almost certainly die of their disease today.”
Mechanism of resistance
Dr. Stanford’s research began with the protein MTF2. He and his colleagues previously found that MTF2 plays a role in erythropoiesis, and the team wanted to determine if MTF2 also plays a role in AML.
Using AML samples from patients treated at The Ottawa Hospital, the researchers found the mean survival was three times longer in patients with normal MTF2 activity than in patients with low MTF2 activity.
“Initially, we thought that MTF2 could be an important biomarker to identify patients who might benefit from experimental therapies,” Dr. Stanford said. “But then we started thinking that if we could understand what MTF2 was doing, maybe we could use this information to develop a new treatment.”
Dr. Stanford and his colleagues discovered that MTF2 represses MDM2, a protein that helps cells resist chemotherapy.
The team found that MTF2-deficient cells overexpress MDM2, which inhibits p53, and this leads to defects in cell-cycle regulation and apoptosis that enable resistance to chemotherapy.
Testing MDM2 inhibitors
Since MDM2 inhibitors are already being tested in clinical trials for other cancers, Dr. Stanford and his colleagues tested these inhibitors in vitro and in mouse models of chemotherapy-resistant AML.
The in vitro experiments included two MDM2 inhibitors—Nutlin3A and MI-773—combined with daunorubicin or cytarabine.
The researchers found that refractory, MTF2-deficient AML cells underwent apoptosis when treated with either daunorubicin or cytarabine in combination with Nutlin3A or MI-773. The effect was comparable to that observed in AML cells with normal MTF2.
The team found that Nutlin3A was more efficient at sensitizing refractory, MTF2-deficient AML cells to daunorubicin, so they used Nutlin3A in the in vivo experiments.
For these experiments, the researchers tested Nutlin3A in mice injected with either chemotherapy-responsive AML cells (with normal MTF2) or refractory, MTF2-deficient AML cells.
Once the mice had “a substantial leukemic burden” (≥ 20% CD45+CD33+ leukemic blasts in their peripheral blood), they were randomized to receive vehicle control, Nutlin3A, standard induction therapy, or induction plus Nutlin3A.
The mice engrafted with chemotherapy-responsive AML cells did not respond to vehicle control or Nutlin3A alone. However, they did respond to standard induction and induction plus Nutlin3A, surviving until the end of the experiment at 16 weeks.
Among the mice engrafted with refractory, MTF2-deficient AML cells, only those animals treated with induction plus Nutlin3A survived until the end of the experiment.
The researchers also noted a “dramatic loss” in the blast-containing CD45+CD33+ and CD34+CD38− populations in mice treated with induction plus Nutlin3A.
To assess residual disease, the researchers performed secondary transplants with cells from mice that had engrafted with refractory, MTF2-deficient AML cells but responded to induction plus Nutlin3A.
The recipient mice had no evidence of AML at 16 weeks after transplant when the experiment ended.
Dr. Stanford and his colleagues are now trying to obtain pharmaceutical-grade MDM2 inhibitors to conduct trials in AML patients at The Ottawa Hospital.
The researchers are also screening libraries of approved drugs to see if any of these can block MDM2, and they are working with a biotech company to develop a test to identify chemotherapy-resistant AML patients who would respond to MDM2 inhibitors.
The current research was supported by grants from the Canadian Cancer Society Research Institute, Canadian Institutes of Health Research, Cancer Research Society, National Institutes of Health, and a Tier 1 Canada Research Chair in Integrative Stem Cell Biology. One study author reported a relationship with Epicypher, Inc. No other conflicts of interest were reported.
Cost-effectiveness of CAR T-cell therapy
Tisagenlecleucel has the potential to be cost-effective for pediatric B-cell acute lymphoblastic leukemia (B-ALL) patients in the United States, according to researchers.
The group found evidence to suggest the chimeric antigen receptor (CAR) T-cell therapy—which has a list price of $475,000—may prove cost-effective if long-term survival benefits are realized.
An analysis indicated that the incremental cost-effectiveness ratio for tisagenlecleucel compared to clofarabine ranged from $37,000 to $78,000 per quality-adjusted life year (QALY) gained.
Melanie D. Whittington, PhD, of the University of Colorado at Denver, Aurora, and her colleagues described this work in JAMA Pediatrics.
For this study, the researchers used a decision analytic model that extrapolated the evidence from clinical trials over a patient’s lifetime to assess life-years gained, QALYs gained, and incremental costs per life-year and QALY gained. The researchers compared tisagenlecleucel to the antineoplastic agent clofarabine.
While tisagenlecleucel has a list price of $475,000, researchers discounted the price by 3% and added several additional costs, such as hospital administration, pretreatment, and potential adverse events, to get to a total discounted cost of about $667,000.
The team estimated that 42.6% of B-ALL patients would be long-term survivors with tisagenlecleucel, 10.34 life-years would be gained, and 9.28 QALYs would be gained.
In comparison, clofarabine had a total discounted cost of approximately $337,000, which included an initial discounted price of $164,000 plus additional treatment and administrative costs.
With clofarabine, 10.8% of B-ALL patients were long-term survivors, 2.43 life-years were gained, and 2.10 QALYs were gained in the model.
Overall, the mean incremental cost-effectiveness ratio was about $46,000 per QALY gained in this base-case model.
In analyses of different scenarios, such as a deeper discount, a different treatment start, or a different calculation of future treatment costs, the cost-effectiveness ratio varied from $37,000 to $78,000 per QALY gained.
The researchers noted that clinical trial evidence for tisagenlecleucel came from single-arm trials, which made the selection of a comparator challenging. Clofarabine was chosen because it had the most similar baseline population characteristics, but the researchers acknowledged that blinatumomab is also frequently used as a treatment for these patients.
“We suspect that tisagenlecleucel would remain cost-effective compared with blinatumomab,” the researchers wrote in JAMA Pediatrics. “A study conducted by other researchers found the incremental cost-effectiveness ratio of tisagenlecleucel versus blinatumomab was similar to the incremental cost-effectiveness ratio of tisagenlecleucel versus clofarabine [i.e., $3,000 more per QALY].”
The researchers suggested that uncertainties in the evidence should be considered as payers are negotiating coverage and payment for tisagenlecleucel.
This study was funded by the Institute for Clinical and Economic Review, which receives some funding from the pharmaceutical industry. Four study authors are employees of the Institute for Clinical and Economic Review.
Tisagenlecleucel has the potential to be cost-effective for pediatric B-cell acute lymphoblastic leukemia (B-ALL) patients in the United States, according to researchers.
The group found evidence to suggest the chimeric antigen receptor (CAR) T-cell therapy—which has a list price of $475,000—may prove cost-effective if long-term survival benefits are realized.
An analysis indicated that the incremental cost-effectiveness ratio for tisagenlecleucel compared to clofarabine ranged from $37,000 to $78,000 per quality-adjusted life year (QALY) gained.
Melanie D. Whittington, PhD, of the University of Colorado at Denver, Aurora, and her colleagues described this work in JAMA Pediatrics.
For this study, the researchers used a decision analytic model that extrapolated the evidence from clinical trials over a patient’s lifetime to assess life-years gained, QALYs gained, and incremental costs per life-year and QALY gained. The researchers compared tisagenlecleucel to the antineoplastic agent clofarabine.
While tisagenlecleucel has a list price of $475,000, researchers discounted the price by 3% and added several additional costs, such as hospital administration, pretreatment, and potential adverse events, to get to a total discounted cost of about $667,000.
The team estimated that 42.6% of B-ALL patients would be long-term survivors with tisagenlecleucel, 10.34 life-years would be gained, and 9.28 QALYs would be gained.
In comparison, clofarabine had a total discounted cost of approximately $337,000, which included an initial discounted price of $164,000 plus additional treatment and administrative costs.
With clofarabine, 10.8% of B-ALL patients were long-term survivors, 2.43 life-years were gained, and 2.10 QALYs were gained in the model.
Overall, the mean incremental cost-effectiveness ratio was about $46,000 per QALY gained in this base-case model.
In analyses of different scenarios, such as a deeper discount, a different treatment start, or a different calculation of future treatment costs, the cost-effectiveness ratio varied from $37,000 to $78,000 per QALY gained.
The researchers noted that clinical trial evidence for tisagenlecleucel came from single-arm trials, which made the selection of a comparator challenging. Clofarabine was chosen because it had the most similar baseline population characteristics, but the researchers acknowledged that blinatumomab is also frequently used as a treatment for these patients.
“We suspect that tisagenlecleucel would remain cost-effective compared with blinatumomab,” the researchers wrote in JAMA Pediatrics. “A study conducted by other researchers found the incremental cost-effectiveness ratio of tisagenlecleucel versus blinatumomab was similar to the incremental cost-effectiveness ratio of tisagenlecleucel versus clofarabine [i.e., $3,000 more per QALY].”
The researchers suggested that uncertainties in the evidence should be considered as payers are negotiating coverage and payment for tisagenlecleucel.
This study was funded by the Institute for Clinical and Economic Review, which receives some funding from the pharmaceutical industry. Four study authors are employees of the Institute for Clinical and Economic Review.
Tisagenlecleucel has the potential to be cost-effective for pediatric B-cell acute lymphoblastic leukemia (B-ALL) patients in the United States, according to researchers.
The group found evidence to suggest the chimeric antigen receptor (CAR) T-cell therapy—which has a list price of $475,000—may prove cost-effective if long-term survival benefits are realized.
An analysis indicated that the incremental cost-effectiveness ratio for tisagenlecleucel compared to clofarabine ranged from $37,000 to $78,000 per quality-adjusted life year (QALY) gained.
Melanie D. Whittington, PhD, of the University of Colorado at Denver, Aurora, and her colleagues described this work in JAMA Pediatrics.
For this study, the researchers used a decision analytic model that extrapolated the evidence from clinical trials over a patient’s lifetime to assess life-years gained, QALYs gained, and incremental costs per life-year and QALY gained. The researchers compared tisagenlecleucel to the antineoplastic agent clofarabine.
While tisagenlecleucel has a list price of $475,000, researchers discounted the price by 3% and added several additional costs, such as hospital administration, pretreatment, and potential adverse events, to get to a total discounted cost of about $667,000.
The team estimated that 42.6% of B-ALL patients would be long-term survivors with tisagenlecleucel, 10.34 life-years would be gained, and 9.28 QALYs would be gained.
In comparison, clofarabine had a total discounted cost of approximately $337,000, which included an initial discounted price of $164,000 plus additional treatment and administrative costs.
With clofarabine, 10.8% of B-ALL patients were long-term survivors, 2.43 life-years were gained, and 2.10 QALYs were gained in the model.
Overall, the mean incremental cost-effectiveness ratio was about $46,000 per QALY gained in this base-case model.
In analyses of different scenarios, such as a deeper discount, a different treatment start, or a different calculation of future treatment costs, the cost-effectiveness ratio varied from $37,000 to $78,000 per QALY gained.
The researchers noted that clinical trial evidence for tisagenlecleucel came from single-arm trials, which made the selection of a comparator challenging. Clofarabine was chosen because it had the most similar baseline population characteristics, but the researchers acknowledged that blinatumomab is also frequently used as a treatment for these patients.
“We suspect that tisagenlecleucel would remain cost-effective compared with blinatumomab,” the researchers wrote in JAMA Pediatrics. “A study conducted by other researchers found the incremental cost-effectiveness ratio of tisagenlecleucel versus blinatumomab was similar to the incremental cost-effectiveness ratio of tisagenlecleucel versus clofarabine [i.e., $3,000 more per QALY].”
The researchers suggested that uncertainties in the evidence should be considered as payers are negotiating coverage and payment for tisagenlecleucel.
This study was funded by the Institute for Clinical and Economic Review, which receives some funding from the pharmaceutical industry. Four study authors are employees of the Institute for Clinical and Economic Review.
CDK8 inhibitor shows activity against AML
DUBROVNIK, CROATIA – The
(AML), but the agent’s mechanism of action is still unclear.Researchers found that several AML cell lines were “highly sensitive” to SEL120, and the inhibitor was active in primary patient samples. SEL120 also reduced tumor growth in mouse models of AML and demonstrated synergy with venetoclax.
The researchers suggest that SEL120 works by affecting the maintenance of AML cells and leukemic stem cells (LSCs), inducing differentiation and, sometimes, apoptosis. However, the mechanism is not well defined.
Eliza Majewska, PhD, of Selvita S.A. in Krakow, Poland, discussed research on SEL120 at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Dr. Majewska explained that CDK8 is a transcriptional kinase working in the context of the Mediator complex, and previous research indicated that CDK8 drives oncogenic transcription in AML (Nature. 2015 Oct 8;526[7572]:273-6).
In a prior study, researchers found that SEL120 inhibits CDK8 activity in AML cells with high levels of STAT phosphorylation (Oncotarget. 2017 May 16;8[20]:33779-95).
Dr. Majewska said the MV4-11 cell line responds particularly well to SEL120, and other sensitive cell lines include SKNO-1, Oci-AML5, GDM-1, KG-1, MOLM-16, and Oci-AML3.
“The fact that STAT signaling was upregulated in those cell lines that were very sensitive to SEL120 gave us the hint that perhaps we are looking at a mechanism of action of the compound that has something to do with leukemic stem cells,” Dr. Majewska said.
In fact, she and her colleagues found that cell lines sensitive to SEL120 had upregulation of genes linked to LSCs and high levels of CD34 surface expression.
Experiments in CD34+ TEX cells showed that SEL120 specifically depletes CD34+ cells, leads to downregulation of stemness-related genes, and induces myeloid differentiation.
After 6 days of treatment with SEL120, TEX cells showed decreased expression of the LSC-linked genes MEIS1 and LILRB2, enrichment of gene sets downregulated in LSCs and linked to differentiation, and increased expression of differentiation markers and immune response genes.
SEL120 also demonstrated antileukemic activity in vivo. The researchers tested SEL120 in a CD34+ model of AML (KG-1) and a FLT3-ITD model of AML (MV4-11).
In both models, SEL120 induced “significant tumor regression” of about 80%. In some cases, the researchers observed apoptosis.
Toxicities observed in the mice included weight loss and upregulation of inflammation.
The researchers also found that SEL120 was synergistic with venetoclax. In fact, the combination of these drugs resulted in “almost complete remission cures” in the MV4-11 model, according to Dr. Majewska.
Finally, she and her colleagues discovered that SEL120 was active against primary patient cells. Samples from three of four patients had a significant reduction in cell numbers after 7 days of treatment with SEL120. For one patient, there were no viable cells on day 7.
Dr. Majewska said a phase 1 trial of SEL120 is planned for 2019 or 2020, and SEL120’s mechanism of action is still under investigation.
“The mechanism of action ... is, in our mind – at least in some cases – linked to the fact that CDK8 functions within the context of the Mediator complex, which contributes to gene expression related to leukemic stem cells,” Dr. Majewska said.
“And when we inhibit this specific transcription, of course, the Mediator complex still works because this is just one of the components of the complex. However, the function that it has is suddenly very different, and it’s actually linked to lack of maintenance of leukemic stem cells, resulting in differentiation [and], in some cases, the induction of apoptosis, but we do not fully understand the mechanism of this induction.”
Dr. Majewska works for Selvita, the company developing SEL120. This research was funded by Selvita, the Leukemia & Lymphoma Society, and the National Centre for Research and Development.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
DUBROVNIK, CROATIA – The
(AML), but the agent’s mechanism of action is still unclear.Researchers found that several AML cell lines were “highly sensitive” to SEL120, and the inhibitor was active in primary patient samples. SEL120 also reduced tumor growth in mouse models of AML and demonstrated synergy with venetoclax.
The researchers suggest that SEL120 works by affecting the maintenance of AML cells and leukemic stem cells (LSCs), inducing differentiation and, sometimes, apoptosis. However, the mechanism is not well defined.
Eliza Majewska, PhD, of Selvita S.A. in Krakow, Poland, discussed research on SEL120 at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Dr. Majewska explained that CDK8 is a transcriptional kinase working in the context of the Mediator complex, and previous research indicated that CDK8 drives oncogenic transcription in AML (Nature. 2015 Oct 8;526[7572]:273-6).
In a prior study, researchers found that SEL120 inhibits CDK8 activity in AML cells with high levels of STAT phosphorylation (Oncotarget. 2017 May 16;8[20]:33779-95).
Dr. Majewska said the MV4-11 cell line responds particularly well to SEL120, and other sensitive cell lines include SKNO-1, Oci-AML5, GDM-1, KG-1, MOLM-16, and Oci-AML3.
“The fact that STAT signaling was upregulated in those cell lines that were very sensitive to SEL120 gave us the hint that perhaps we are looking at a mechanism of action of the compound that has something to do with leukemic stem cells,” Dr. Majewska said.
In fact, she and her colleagues found that cell lines sensitive to SEL120 had upregulation of genes linked to LSCs and high levels of CD34 surface expression.
Experiments in CD34+ TEX cells showed that SEL120 specifically depletes CD34+ cells, leads to downregulation of stemness-related genes, and induces myeloid differentiation.
After 6 days of treatment with SEL120, TEX cells showed decreased expression of the LSC-linked genes MEIS1 and LILRB2, enrichment of gene sets downregulated in LSCs and linked to differentiation, and increased expression of differentiation markers and immune response genes.
SEL120 also demonstrated antileukemic activity in vivo. The researchers tested SEL120 in a CD34+ model of AML (KG-1) and a FLT3-ITD model of AML (MV4-11).
In both models, SEL120 induced “significant tumor regression” of about 80%. In some cases, the researchers observed apoptosis.
Toxicities observed in the mice included weight loss and upregulation of inflammation.
The researchers also found that SEL120 was synergistic with venetoclax. In fact, the combination of these drugs resulted in “almost complete remission cures” in the MV4-11 model, according to Dr. Majewska.
Finally, she and her colleagues discovered that SEL120 was active against primary patient cells. Samples from three of four patients had a significant reduction in cell numbers after 7 days of treatment with SEL120. For one patient, there were no viable cells on day 7.
Dr. Majewska said a phase 1 trial of SEL120 is planned for 2019 or 2020, and SEL120’s mechanism of action is still under investigation.
“The mechanism of action ... is, in our mind – at least in some cases – linked to the fact that CDK8 functions within the context of the Mediator complex, which contributes to gene expression related to leukemic stem cells,” Dr. Majewska said.
“And when we inhibit this specific transcription, of course, the Mediator complex still works because this is just one of the components of the complex. However, the function that it has is suddenly very different, and it’s actually linked to lack of maintenance of leukemic stem cells, resulting in differentiation [and], in some cases, the induction of apoptosis, but we do not fully understand the mechanism of this induction.”
Dr. Majewska works for Selvita, the company developing SEL120. This research was funded by Selvita, the Leukemia & Lymphoma Society, and the National Centre for Research and Development.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
DUBROVNIK, CROATIA – The
(AML), but the agent’s mechanism of action is still unclear.Researchers found that several AML cell lines were “highly sensitive” to SEL120, and the inhibitor was active in primary patient samples. SEL120 also reduced tumor growth in mouse models of AML and demonstrated synergy with venetoclax.
The researchers suggest that SEL120 works by affecting the maintenance of AML cells and leukemic stem cells (LSCs), inducing differentiation and, sometimes, apoptosis. However, the mechanism is not well defined.
Eliza Majewska, PhD, of Selvita S.A. in Krakow, Poland, discussed research on SEL120 at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Dr. Majewska explained that CDK8 is a transcriptional kinase working in the context of the Mediator complex, and previous research indicated that CDK8 drives oncogenic transcription in AML (Nature. 2015 Oct 8;526[7572]:273-6).
In a prior study, researchers found that SEL120 inhibits CDK8 activity in AML cells with high levels of STAT phosphorylation (Oncotarget. 2017 May 16;8[20]:33779-95).
Dr. Majewska said the MV4-11 cell line responds particularly well to SEL120, and other sensitive cell lines include SKNO-1, Oci-AML5, GDM-1, KG-1, MOLM-16, and Oci-AML3.
“The fact that STAT signaling was upregulated in those cell lines that were very sensitive to SEL120 gave us the hint that perhaps we are looking at a mechanism of action of the compound that has something to do with leukemic stem cells,” Dr. Majewska said.
In fact, she and her colleagues found that cell lines sensitive to SEL120 had upregulation of genes linked to LSCs and high levels of CD34 surface expression.
Experiments in CD34+ TEX cells showed that SEL120 specifically depletes CD34+ cells, leads to downregulation of stemness-related genes, and induces myeloid differentiation.
After 6 days of treatment with SEL120, TEX cells showed decreased expression of the LSC-linked genes MEIS1 and LILRB2, enrichment of gene sets downregulated in LSCs and linked to differentiation, and increased expression of differentiation markers and immune response genes.
SEL120 also demonstrated antileukemic activity in vivo. The researchers tested SEL120 in a CD34+ model of AML (KG-1) and a FLT3-ITD model of AML (MV4-11).
In both models, SEL120 induced “significant tumor regression” of about 80%. In some cases, the researchers observed apoptosis.
Toxicities observed in the mice included weight loss and upregulation of inflammation.
The researchers also found that SEL120 was synergistic with venetoclax. In fact, the combination of these drugs resulted in “almost complete remission cures” in the MV4-11 model, according to Dr. Majewska.
Finally, she and her colleagues discovered that SEL120 was active against primary patient cells. Samples from three of four patients had a significant reduction in cell numbers after 7 days of treatment with SEL120. For one patient, there were no viable cells on day 7.
Dr. Majewska said a phase 1 trial of SEL120 is planned for 2019 or 2020, and SEL120’s mechanism of action is still under investigation.
“The mechanism of action ... is, in our mind – at least in some cases – linked to the fact that CDK8 functions within the context of the Mediator complex, which contributes to gene expression related to leukemic stem cells,” Dr. Majewska said.
“And when we inhibit this specific transcription, of course, the Mediator complex still works because this is just one of the components of the complex. However, the function that it has is suddenly very different, and it’s actually linked to lack of maintenance of leukemic stem cells, resulting in differentiation [and], in some cases, the induction of apoptosis, but we do not fully understand the mechanism of this induction.”
Dr. Majewska works for Selvita, the company developing SEL120. This research was funded by Selvita, the Leukemia & Lymphoma Society, and the National Centre for Research and Development.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
EXPERT ANALYSIS FROM LEUKEMIA AND LYMPHOMA 2018
When is it CMML?
DUBROVNIK, CROATIA –
in 2018.Even with updated World Health Organization (WHO) criteria, karyotyping, and genetic analyses, it can be difficult to distinguish CMML from other conditions, according to Nadira Durakovic, MD, PhD, of the University Hospital Centre Zagreb (Croatia).
However, there are characteristics that differentiate CMML from myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPNs), and atypical chronic myeloid leukemia (CML), Dr. Durakovic said at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Studies have suggested that monocyte subset distribution analysis can be useful for diagnosing CMML.
According to the 2016 WHO classification, patients have CMML if:
- They have persistent peripheral blood monocytosis (1×109/L), with monocytes accounting for 10% of the white blood cell count.
- They do not meet WHO criteria for BCR-ABL1-positive CML, primary myelofibrosis, polycythemia vera, or essential thrombocythemia.
- There is no evidence of PCM1-JAK2 or PDGFRA, PDGFRB, or FGFR1 rearrangement.
- They have fewer than 20% blasts in the blood and bone marrow they have dysplasia in one or more myeloid lineages.
If myelodysplasia is absent or minimal, an acquired clonal cytogenetic or molecular genetic abnormality must be present. Alternatively, if patients have monocytosis that has persisted for at least 3 months, and all other causes of monocytosis have been excluded, “you can say that your patient has CMML,” Dr. Durakovic said.
Other causes of monocytosis include infections, malignancies, medications, inflammatory conditions, and other conditions, such as pregnancy.
However, Dr. Durakovic pointed out that the cause of monocytosis cannot always be determined, and, in some cases, CMML patients may not meet the WHO criteria.
“There are cases where there just aren’t enough monocytes to fulfill the WHO criteria,” Dr. Durakovic said. “You can have a patient with peripheral blood cytopenia and monocytosis who does not have 1,000 monocytes. Patients can have progressive dysplasia, can have splenomegaly, be really sick, but fail to meet WHO criteria.”
Differential diagnosis
“Differentiating CMML from myelodysplastic syndromes can be tough,” Dr. Durakovic said. “There are dysplastic features that are present in CMML ... but, in CMML, they are more subtle, and they are more difficult to appreciate than in myelodysplastic syndromes.”
The ratio of myeloid to erythroid cells is elevated in CMML, and patients may have atypical monocytes (paramyeloid cells) that are unique to CMML.
Dr. Durakovic noted that megakaryocyte dysplasia in CMML can be characterized by “myeloproliferative megakaryocytes,” which are large cells that cluster and have hyperlobulated nuclei, or “MDS megakaryocytes,” which are small, solitary cells with hypolobulated nuclei.
She noted that “MPN phenotype” CMML is characterized by leukocytosis, monocytosis, hepatomegaly, splenomegaly, and clinical features of myeloproliferation (fatigue, night sweats, bone pain, weight loss, etc.).
Thirty percent of cases are associated with splenomegaly, and 30% of patients can have an increase in bone marrow reticulin fibrosis.
Dr. Durakovic also noted that a prior MPN diagnosis excludes CMML. The presence of common MPN mutations, such as JAK2, CALR, or MPL, suggests a patient has an MPN with monocytosis rather than CMML.
Patients who have unclassified MPNs or MDS, rather than CMML, either do not have 1,000 monocytes or the monocytes do not represent more than 10% of the differential, Dr. Durakovic said.
It can also be difficult to differentiate CMML from atypical CML.
“Atypical CML is characterized by profound dysgranulopoiesis, absence of the BCR-ABL1 fusion gene, and neutrophilia,” Dr. Durakovic explained. “Those patients [commonly] have monocytosis, but, here, that 10% rule is valuable because their monocytes comprise less than 10% of the entire white blood cell count.”
Karyotyping, genotyping, and immunophenotyping
“There is no disease-defining karyotype abnormality [in CMML],” Dr. Durakovic said.
She said 30% of patients have abnormal karyotype, and the most common abnormality is trisomy 8. Unlike in patients with MDS, del(5q) and monosomal karyotypes are infrequent in patients with CMML.
Similarly, there are no “disease-defining” mutations or genetic changes in CMML, although CMML is genetically distinct from MDS, Dr. Durakovic said.
For instance, SRSF2 encodes a component of the spliceosome that is mutated in almost half of CMML patients and less than 10% of MDS patients. Likewise, ASLX1 and TET2 are “much more frequently involved” in CMML than in MDS, Dr. Durakovic said.
In a 2012 study of 275 CMML patients, researchers found that 93% of patients had at least one somatic mutation in nine recurrently mutated genes – SRFS2, ASXL1, CBL, EZH2, JAK2V617F, KRAS, NRAS, RUNX1, and TET2 (Blood. 2012;120:3080-8).
However, Dr. Durakovic noted that these mutations are found in other disorders as well, so this information may not be helpful in differentiating CMML from other disorders.
A 2015 study revealed a technique that does appear useful for identifying CMML – monocyte subset distribution analysis. For this analysis, monocytes are divided into the following categories:
- Classical/MO1 (CD14bright/CD16−).
- Intermediate/MO2 (CD14bright/CD16+).
- Nonclassical/MO3 (CD14dim/CD16+).
The researchers found that CMML patients had an increase in the fraction of classical monocytes (with a cutoff value of 94%), as compared to healthy control subjects, patients with another hematologic disorder, and patients with reactive monocytosis (Blood. 2015 Jun 4;125[23]:3618-26).
A 2018 study confirmed that monocyte subset distribution analysis could differentiate CMML from other hematologic disorders, with the exception of atypical CML. This study also suggested that a decreased percentage of non-classical monocytes was more sensitive than an increased percentage of classical monocytes (Am J Clin Pathol. 2018 Aug 30;150[4]:293-302).
Despite the differences between these studies, “monocyte subset distribution analysis is showing promise as a method of identifying hard-to-identify CMML patients with ease and affordability,” Dr. Durakovic said.
She added that the technique can be implemented in clinical practice using the Hematoflow solution.
Dr. Durakovic did not report any conflicts of interest.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
DUBROVNIK, CROATIA –
in 2018.Even with updated World Health Organization (WHO) criteria, karyotyping, and genetic analyses, it can be difficult to distinguish CMML from other conditions, according to Nadira Durakovic, MD, PhD, of the University Hospital Centre Zagreb (Croatia).
However, there are characteristics that differentiate CMML from myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPNs), and atypical chronic myeloid leukemia (CML), Dr. Durakovic said at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Studies have suggested that monocyte subset distribution analysis can be useful for diagnosing CMML.
According to the 2016 WHO classification, patients have CMML if:
- They have persistent peripheral blood monocytosis (1×109/L), with monocytes accounting for 10% of the white blood cell count.
- They do not meet WHO criteria for BCR-ABL1-positive CML, primary myelofibrosis, polycythemia vera, or essential thrombocythemia.
- There is no evidence of PCM1-JAK2 or PDGFRA, PDGFRB, or FGFR1 rearrangement.
- They have fewer than 20% blasts in the blood and bone marrow they have dysplasia in one or more myeloid lineages.
If myelodysplasia is absent or minimal, an acquired clonal cytogenetic or molecular genetic abnormality must be present. Alternatively, if patients have monocytosis that has persisted for at least 3 months, and all other causes of monocytosis have been excluded, “you can say that your patient has CMML,” Dr. Durakovic said.
Other causes of monocytosis include infections, malignancies, medications, inflammatory conditions, and other conditions, such as pregnancy.
However, Dr. Durakovic pointed out that the cause of monocytosis cannot always be determined, and, in some cases, CMML patients may not meet the WHO criteria.
“There are cases where there just aren’t enough monocytes to fulfill the WHO criteria,” Dr. Durakovic said. “You can have a patient with peripheral blood cytopenia and monocytosis who does not have 1,000 monocytes. Patients can have progressive dysplasia, can have splenomegaly, be really sick, but fail to meet WHO criteria.”
Differential diagnosis
“Differentiating CMML from myelodysplastic syndromes can be tough,” Dr. Durakovic said. “There are dysplastic features that are present in CMML ... but, in CMML, they are more subtle, and they are more difficult to appreciate than in myelodysplastic syndromes.”
The ratio of myeloid to erythroid cells is elevated in CMML, and patients may have atypical monocytes (paramyeloid cells) that are unique to CMML.
Dr. Durakovic noted that megakaryocyte dysplasia in CMML can be characterized by “myeloproliferative megakaryocytes,” which are large cells that cluster and have hyperlobulated nuclei, or “MDS megakaryocytes,” which are small, solitary cells with hypolobulated nuclei.
She noted that “MPN phenotype” CMML is characterized by leukocytosis, monocytosis, hepatomegaly, splenomegaly, and clinical features of myeloproliferation (fatigue, night sweats, bone pain, weight loss, etc.).
Thirty percent of cases are associated with splenomegaly, and 30% of patients can have an increase in bone marrow reticulin fibrosis.
Dr. Durakovic also noted that a prior MPN diagnosis excludes CMML. The presence of common MPN mutations, such as JAK2, CALR, or MPL, suggests a patient has an MPN with monocytosis rather than CMML.
Patients who have unclassified MPNs or MDS, rather than CMML, either do not have 1,000 monocytes or the monocytes do not represent more than 10% of the differential, Dr. Durakovic said.
It can also be difficult to differentiate CMML from atypical CML.
“Atypical CML is characterized by profound dysgranulopoiesis, absence of the BCR-ABL1 fusion gene, and neutrophilia,” Dr. Durakovic explained. “Those patients [commonly] have monocytosis, but, here, that 10% rule is valuable because their monocytes comprise less than 10% of the entire white blood cell count.”
Karyotyping, genotyping, and immunophenotyping
“There is no disease-defining karyotype abnormality [in CMML],” Dr. Durakovic said.
She said 30% of patients have abnormal karyotype, and the most common abnormality is trisomy 8. Unlike in patients with MDS, del(5q) and monosomal karyotypes are infrequent in patients with CMML.
Similarly, there are no “disease-defining” mutations or genetic changes in CMML, although CMML is genetically distinct from MDS, Dr. Durakovic said.
For instance, SRSF2 encodes a component of the spliceosome that is mutated in almost half of CMML patients and less than 10% of MDS patients. Likewise, ASLX1 and TET2 are “much more frequently involved” in CMML than in MDS, Dr. Durakovic said.
In a 2012 study of 275 CMML patients, researchers found that 93% of patients had at least one somatic mutation in nine recurrently mutated genes – SRFS2, ASXL1, CBL, EZH2, JAK2V617F, KRAS, NRAS, RUNX1, and TET2 (Blood. 2012;120:3080-8).
However, Dr. Durakovic noted that these mutations are found in other disorders as well, so this information may not be helpful in differentiating CMML from other disorders.
A 2015 study revealed a technique that does appear useful for identifying CMML – monocyte subset distribution analysis. For this analysis, monocytes are divided into the following categories:
- Classical/MO1 (CD14bright/CD16−).
- Intermediate/MO2 (CD14bright/CD16+).
- Nonclassical/MO3 (CD14dim/CD16+).
The researchers found that CMML patients had an increase in the fraction of classical monocytes (with a cutoff value of 94%), as compared to healthy control subjects, patients with another hematologic disorder, and patients with reactive monocytosis (Blood. 2015 Jun 4;125[23]:3618-26).
A 2018 study confirmed that monocyte subset distribution analysis could differentiate CMML from other hematologic disorders, with the exception of atypical CML. This study also suggested that a decreased percentage of non-classical monocytes was more sensitive than an increased percentage of classical monocytes (Am J Clin Pathol. 2018 Aug 30;150[4]:293-302).
Despite the differences between these studies, “monocyte subset distribution analysis is showing promise as a method of identifying hard-to-identify CMML patients with ease and affordability,” Dr. Durakovic said.
She added that the technique can be implemented in clinical practice using the Hematoflow solution.
Dr. Durakovic did not report any conflicts of interest.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
DUBROVNIK, CROATIA –
in 2018.Even with updated World Health Organization (WHO) criteria, karyotyping, and genetic analyses, it can be difficult to distinguish CMML from other conditions, according to Nadira Durakovic, MD, PhD, of the University Hospital Centre Zagreb (Croatia).
However, there are characteristics that differentiate CMML from myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPNs), and atypical chronic myeloid leukemia (CML), Dr. Durakovic said at Leukemia and Lymphoma, a meeting jointly sponsored by the University of Texas MD Anderson Cancer Center and the School of Medicine at the University of Zagreb, Croatia.
Studies have suggested that monocyte subset distribution analysis can be useful for diagnosing CMML.
According to the 2016 WHO classification, patients have CMML if:
- They have persistent peripheral blood monocytosis (1×109/L), with monocytes accounting for 10% of the white blood cell count.
- They do not meet WHO criteria for BCR-ABL1-positive CML, primary myelofibrosis, polycythemia vera, or essential thrombocythemia.
- There is no evidence of PCM1-JAK2 or PDGFRA, PDGFRB, or FGFR1 rearrangement.
- They have fewer than 20% blasts in the blood and bone marrow they have dysplasia in one or more myeloid lineages.
If myelodysplasia is absent or minimal, an acquired clonal cytogenetic or molecular genetic abnormality must be present. Alternatively, if patients have monocytosis that has persisted for at least 3 months, and all other causes of monocytosis have been excluded, “you can say that your patient has CMML,” Dr. Durakovic said.
Other causes of monocytosis include infections, malignancies, medications, inflammatory conditions, and other conditions, such as pregnancy.
However, Dr. Durakovic pointed out that the cause of monocytosis cannot always be determined, and, in some cases, CMML patients may not meet the WHO criteria.
“There are cases where there just aren’t enough monocytes to fulfill the WHO criteria,” Dr. Durakovic said. “You can have a patient with peripheral blood cytopenia and monocytosis who does not have 1,000 monocytes. Patients can have progressive dysplasia, can have splenomegaly, be really sick, but fail to meet WHO criteria.”
Differential diagnosis
“Differentiating CMML from myelodysplastic syndromes can be tough,” Dr. Durakovic said. “There are dysplastic features that are present in CMML ... but, in CMML, they are more subtle, and they are more difficult to appreciate than in myelodysplastic syndromes.”
The ratio of myeloid to erythroid cells is elevated in CMML, and patients may have atypical monocytes (paramyeloid cells) that are unique to CMML.
Dr. Durakovic noted that megakaryocyte dysplasia in CMML can be characterized by “myeloproliferative megakaryocytes,” which are large cells that cluster and have hyperlobulated nuclei, or “MDS megakaryocytes,” which are small, solitary cells with hypolobulated nuclei.
She noted that “MPN phenotype” CMML is characterized by leukocytosis, monocytosis, hepatomegaly, splenomegaly, and clinical features of myeloproliferation (fatigue, night sweats, bone pain, weight loss, etc.).
Thirty percent of cases are associated with splenomegaly, and 30% of patients can have an increase in bone marrow reticulin fibrosis.
Dr. Durakovic also noted that a prior MPN diagnosis excludes CMML. The presence of common MPN mutations, such as JAK2, CALR, or MPL, suggests a patient has an MPN with monocytosis rather than CMML.
Patients who have unclassified MPNs or MDS, rather than CMML, either do not have 1,000 monocytes or the monocytes do not represent more than 10% of the differential, Dr. Durakovic said.
It can also be difficult to differentiate CMML from atypical CML.
“Atypical CML is characterized by profound dysgranulopoiesis, absence of the BCR-ABL1 fusion gene, and neutrophilia,” Dr. Durakovic explained. “Those patients [commonly] have monocytosis, but, here, that 10% rule is valuable because their monocytes comprise less than 10% of the entire white blood cell count.”
Karyotyping, genotyping, and immunophenotyping
“There is no disease-defining karyotype abnormality [in CMML],” Dr. Durakovic said.
She said 30% of patients have abnormal karyotype, and the most common abnormality is trisomy 8. Unlike in patients with MDS, del(5q) and monosomal karyotypes are infrequent in patients with CMML.
Similarly, there are no “disease-defining” mutations or genetic changes in CMML, although CMML is genetically distinct from MDS, Dr. Durakovic said.
For instance, SRSF2 encodes a component of the spliceosome that is mutated in almost half of CMML patients and less than 10% of MDS patients. Likewise, ASLX1 and TET2 are “much more frequently involved” in CMML than in MDS, Dr. Durakovic said.
In a 2012 study of 275 CMML patients, researchers found that 93% of patients had at least one somatic mutation in nine recurrently mutated genes – SRFS2, ASXL1, CBL, EZH2, JAK2V617F, KRAS, NRAS, RUNX1, and TET2 (Blood. 2012;120:3080-8).
However, Dr. Durakovic noted that these mutations are found in other disorders as well, so this information may not be helpful in differentiating CMML from other disorders.
A 2015 study revealed a technique that does appear useful for identifying CMML – monocyte subset distribution analysis. For this analysis, monocytes are divided into the following categories:
- Classical/MO1 (CD14bright/CD16−).
- Intermediate/MO2 (CD14bright/CD16+).
- Nonclassical/MO3 (CD14dim/CD16+).
The researchers found that CMML patients had an increase in the fraction of classical monocytes (with a cutoff value of 94%), as compared to healthy control subjects, patients with another hematologic disorder, and patients with reactive monocytosis (Blood. 2015 Jun 4;125[23]:3618-26).
A 2018 study confirmed that monocyte subset distribution analysis could differentiate CMML from other hematologic disorders, with the exception of atypical CML. This study also suggested that a decreased percentage of non-classical monocytes was more sensitive than an increased percentage of classical monocytes (Am J Clin Pathol. 2018 Aug 30;150[4]:293-302).
Despite the differences between these studies, “monocyte subset distribution analysis is showing promise as a method of identifying hard-to-identify CMML patients with ease and affordability,” Dr. Durakovic said.
She added that the technique can be implemented in clinical practice using the Hematoflow solution.
Dr. Durakovic did not report any conflicts of interest.
The Leukemia and Lymphoma meeting is organized by Jonathan Wood & Association, which is owned by the parent company of this news organization.
EXPERT ANALYSIS FROM LEUKEMIA AND LYMPHOMA 2018
Study supports sequencing in kids with cancer
SAN DIEGO—Comprehensive next-generation sequencing is both feasible and clinically useful in pediatric cancer patients, a new study suggests.
Researchers sequenced samples from 253 pediatric cancer patients and found that, in 79% of cases, there was at least one finding that could help guide care.
Scott Newman, PhD, of St. Jude Children’s Research Hospital in Memphis, Tennessee, presented these findings at the American Society of Human Genetics (ASHG) 2018 Annual Meeting (abstract 52).
The researchers conducted whole-genome, exome, and transcriptome sequencing of the patients’ tumors, as well as sequencing non-cancerous tissues from the same patients.
Of the 253 patients studied, 123 had hematologic malignancies.
The researchers found a mean of four pathogenic or likely pathogenic variants per patient (range, 0-18). This included prognostic (21.8%) and diagnostic (15.1%) variants as well as variants that could be targeted therapeutically (6.8%).
In all, 79% of the patients had at least one variant that was targetable, diagnostic, or prognostic. And test results were available within about 40 days, quickly enough that they could be used to guide care.
“With results available in a clinically relevant time frame, and pricing becoming increasingly comparable to the radiology and pathology tests, WGS [whole-genome sequencing] is becoming more accessible to pediatric oncology patients,” Dr. Newman said.
This work was part of the Genomes for Kids study (G4K), an effort to understand how best to use genetic data for pediatric cancer diagnosis and treatment. St. Jude has compiled the information from G4K into a publicly accessible online database.
The researchers have continued to perform sequencing on current patients, and, since the original study ended, have successfully used this method on roughly 300 additional patients. The team plans to continue studying sequencing methods in hopes of producing clinically applicable data more quickly.
G4K was sponsored by St. Jude.
SAN DIEGO—Comprehensive next-generation sequencing is both feasible and clinically useful in pediatric cancer patients, a new study suggests.
Researchers sequenced samples from 253 pediatric cancer patients and found that, in 79% of cases, there was at least one finding that could help guide care.
Scott Newman, PhD, of St. Jude Children’s Research Hospital in Memphis, Tennessee, presented these findings at the American Society of Human Genetics (ASHG) 2018 Annual Meeting (abstract 52).
The researchers conducted whole-genome, exome, and transcriptome sequencing of the patients’ tumors, as well as sequencing non-cancerous tissues from the same patients.
Of the 253 patients studied, 123 had hematologic malignancies.
The researchers found a mean of four pathogenic or likely pathogenic variants per patient (range, 0-18). This included prognostic (21.8%) and diagnostic (15.1%) variants as well as variants that could be targeted therapeutically (6.8%).
In all, 79% of the patients had at least one variant that was targetable, diagnostic, or prognostic. And test results were available within about 40 days, quickly enough that they could be used to guide care.
“With results available in a clinically relevant time frame, and pricing becoming increasingly comparable to the radiology and pathology tests, WGS [whole-genome sequencing] is becoming more accessible to pediatric oncology patients,” Dr. Newman said.
This work was part of the Genomes for Kids study (G4K), an effort to understand how best to use genetic data for pediatric cancer diagnosis and treatment. St. Jude has compiled the information from G4K into a publicly accessible online database.
The researchers have continued to perform sequencing on current patients, and, since the original study ended, have successfully used this method on roughly 300 additional patients. The team plans to continue studying sequencing methods in hopes of producing clinically applicable data more quickly.
G4K was sponsored by St. Jude.
SAN DIEGO—Comprehensive next-generation sequencing is both feasible and clinically useful in pediatric cancer patients, a new study suggests.
Researchers sequenced samples from 253 pediatric cancer patients and found that, in 79% of cases, there was at least one finding that could help guide care.
Scott Newman, PhD, of St. Jude Children’s Research Hospital in Memphis, Tennessee, presented these findings at the American Society of Human Genetics (ASHG) 2018 Annual Meeting (abstract 52).
The researchers conducted whole-genome, exome, and transcriptome sequencing of the patients’ tumors, as well as sequencing non-cancerous tissues from the same patients.
Of the 253 patients studied, 123 had hematologic malignancies.
The researchers found a mean of four pathogenic or likely pathogenic variants per patient (range, 0-18). This included prognostic (21.8%) and diagnostic (15.1%) variants as well as variants that could be targeted therapeutically (6.8%).
In all, 79% of the patients had at least one variant that was targetable, diagnostic, or prognostic. And test results were available within about 40 days, quickly enough that they could be used to guide care.
“With results available in a clinically relevant time frame, and pricing becoming increasingly comparable to the radiology and pathology tests, WGS [whole-genome sequencing] is becoming more accessible to pediatric oncology patients,” Dr. Newman said.
This work was part of the Genomes for Kids study (G4K), an effort to understand how best to use genetic data for pediatric cancer diagnosis and treatment. St. Jude has compiled the information from G4K into a publicly accessible online database.
The researchers have continued to perform sequencing on current patients, and, since the original study ended, have successfully used this method on roughly 300 additional patients. The team plans to continue studying sequencing methods in hopes of producing clinically applicable data more quickly.
G4K was sponsored by St. Jude.
‘Intense’ end-of-life care may be common in HSCT recipients
Patients who die within a year of allogeneic hematopoietic stem cell transplant (HSCT) tend to receive “medically intense” end-of-life care, an analysis suggests.
Researchers studied more than 2,000 patients who died within a year of allogeneic HSCT and found that a majority of the patients died in the hospital, and about half of them were admitted to the intensive care unit (ICU).
However, patient age, underlying diagnosis, and other factors influenced the likelihood of receiving intense end-of-life care.
For example, patients diagnosed with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) were less likely than patients with acute lymphoblastic leukemia (ALL) to receive medically intense care.
Emily Johnston, MD, of the University of Alabama at Birmingham, and her colleagues reported these findings in the Journal of Clinical Oncology.
The researchers studied 2,135 patients in California who underwent inpatient HSCT and died within a year of the transplant (not as a result of peripartum events or trauma) between 2000 and 2013.
Fifty-three percent of the patients received some type of medically intense intervention, and 57% had at least two types of intense interventions.
Eighty-three percent of patients died in hospital, and 43% spent all of their last 30 days in the hospital.
Forty-nine percent of patients were admitted to the ICU, 45% were intubated, 22% underwent hemodialysis, and 8% received cardiopulmonary resuscitation.
Factors associated with intense care
The researchers said receipt of a medically intense intervention varied by age at death, underlying diagnosis, year of HSCT, location of care, and comorbidities. However, use of intense interventions did not vary according to sex, race/ethnicity, insurance type, or income.
Compared to patients age 60 and older, patients in the following age groups were more likely to receive medically intense interventions:
- Ages 15 to 21—odds ratio (OR)=2.6 (P<0.001)
- Ages 30 to 39—OR=1.8 (P<0.01)
- Ages 40 to 49—OR=1.4 (P<0.05).
Patients with comorbidities were more likely to receive intense interventions as well. The OR was 1.6 (P<0.01) for patients with one comorbidity and 2.5 (P<0.001) for patients with two or more comorbidities.
Patients with AML or MDS were less likely than patients with ALL to receive a medically intense intervention—OR=0.7 (P<0.05).
Patients who were transplanted between 2000 and 2004 were less likely to receive an intense intervention than patients transplanted between 2010 and 2013—OR=0.7 (P<0.01).
Patients who changed hospitals between HSCT and death were less likely to receive an intense intervention than patients who stayed at the same hospital. The OR was 0.3 if they transferred to a community hospital and 0.4 if they transferred to a specialty hospital (P<0.001 for both).
Patients living in rural areas were less likely than urban patients to receive a medically intense intervention—OR=0.6 (P<0.05).
“From our data, we understand there is a correlation with high-intensity end-of-life care in patients who die within one year after receiving a stem cell transplant, but we are still unsure if that was the care they wanted,” Dr. Johnston said.
“The findings suggest that, as oncologists, we need to start having end-of-life care conversations earlier with patients to determine if a high-intensity treatment plan is consistent with their goals or if a lower-intensity treatment plan is best. It’s not a one-size-fits-all approach in end-of-life care.”
This research was supported by Stanford University. One study author reported relationships with Corvus Pharmaceuticals, Shire Pharmaceuticals, and Adaptive Biotechnologies. All other authors reported no conflicts.
Patients who die within a year of allogeneic hematopoietic stem cell transplant (HSCT) tend to receive “medically intense” end-of-life care, an analysis suggests.
Researchers studied more than 2,000 patients who died within a year of allogeneic HSCT and found that a majority of the patients died in the hospital, and about half of them were admitted to the intensive care unit (ICU).
However, patient age, underlying diagnosis, and other factors influenced the likelihood of receiving intense end-of-life care.
For example, patients diagnosed with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) were less likely than patients with acute lymphoblastic leukemia (ALL) to receive medically intense care.
Emily Johnston, MD, of the University of Alabama at Birmingham, and her colleagues reported these findings in the Journal of Clinical Oncology.
The researchers studied 2,135 patients in California who underwent inpatient HSCT and died within a year of the transplant (not as a result of peripartum events or trauma) between 2000 and 2013.
Fifty-three percent of the patients received some type of medically intense intervention, and 57% had at least two types of intense interventions.
Eighty-three percent of patients died in hospital, and 43% spent all of their last 30 days in the hospital.
Forty-nine percent of patients were admitted to the ICU, 45% were intubated, 22% underwent hemodialysis, and 8% received cardiopulmonary resuscitation.
Factors associated with intense care
The researchers said receipt of a medically intense intervention varied by age at death, underlying diagnosis, year of HSCT, location of care, and comorbidities. However, use of intense interventions did not vary according to sex, race/ethnicity, insurance type, or income.
Compared to patients age 60 and older, patients in the following age groups were more likely to receive medically intense interventions:
- Ages 15 to 21—odds ratio (OR)=2.6 (P<0.001)
- Ages 30 to 39—OR=1.8 (P<0.01)
- Ages 40 to 49—OR=1.4 (P<0.05).
Patients with comorbidities were more likely to receive intense interventions as well. The OR was 1.6 (P<0.01) for patients with one comorbidity and 2.5 (P<0.001) for patients with two or more comorbidities.
Patients with AML or MDS were less likely than patients with ALL to receive a medically intense intervention—OR=0.7 (P<0.05).
Patients who were transplanted between 2000 and 2004 were less likely to receive an intense intervention than patients transplanted between 2010 and 2013—OR=0.7 (P<0.01).
Patients who changed hospitals between HSCT and death were less likely to receive an intense intervention than patients who stayed at the same hospital. The OR was 0.3 if they transferred to a community hospital and 0.4 if they transferred to a specialty hospital (P<0.001 for both).
Patients living in rural areas were less likely than urban patients to receive a medically intense intervention—OR=0.6 (P<0.05).
“From our data, we understand there is a correlation with high-intensity end-of-life care in patients who die within one year after receiving a stem cell transplant, but we are still unsure if that was the care they wanted,” Dr. Johnston said.
“The findings suggest that, as oncologists, we need to start having end-of-life care conversations earlier with patients to determine if a high-intensity treatment plan is consistent with their goals or if a lower-intensity treatment plan is best. It’s not a one-size-fits-all approach in end-of-life care.”
This research was supported by Stanford University. One study author reported relationships with Corvus Pharmaceuticals, Shire Pharmaceuticals, and Adaptive Biotechnologies. All other authors reported no conflicts.
Patients who die within a year of allogeneic hematopoietic stem cell transplant (HSCT) tend to receive “medically intense” end-of-life care, an analysis suggests.
Researchers studied more than 2,000 patients who died within a year of allogeneic HSCT and found that a majority of the patients died in the hospital, and about half of them were admitted to the intensive care unit (ICU).
However, patient age, underlying diagnosis, and other factors influenced the likelihood of receiving intense end-of-life care.
For example, patients diagnosed with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) were less likely than patients with acute lymphoblastic leukemia (ALL) to receive medically intense care.
Emily Johnston, MD, of the University of Alabama at Birmingham, and her colleagues reported these findings in the Journal of Clinical Oncology.
The researchers studied 2,135 patients in California who underwent inpatient HSCT and died within a year of the transplant (not as a result of peripartum events or trauma) between 2000 and 2013.
Fifty-three percent of the patients received some type of medically intense intervention, and 57% had at least two types of intense interventions.
Eighty-three percent of patients died in hospital, and 43% spent all of their last 30 days in the hospital.
Forty-nine percent of patients were admitted to the ICU, 45% were intubated, 22% underwent hemodialysis, and 8% received cardiopulmonary resuscitation.
Factors associated with intense care
The researchers said receipt of a medically intense intervention varied by age at death, underlying diagnosis, year of HSCT, location of care, and comorbidities. However, use of intense interventions did not vary according to sex, race/ethnicity, insurance type, or income.
Compared to patients age 60 and older, patients in the following age groups were more likely to receive medically intense interventions:
- Ages 15 to 21—odds ratio (OR)=2.6 (P<0.001)
- Ages 30 to 39—OR=1.8 (P<0.01)
- Ages 40 to 49—OR=1.4 (P<0.05).
Patients with comorbidities were more likely to receive intense interventions as well. The OR was 1.6 (P<0.01) for patients with one comorbidity and 2.5 (P<0.001) for patients with two or more comorbidities.
Patients with AML or MDS were less likely than patients with ALL to receive a medically intense intervention—OR=0.7 (P<0.05).
Patients who were transplanted between 2000 and 2004 were less likely to receive an intense intervention than patients transplanted between 2010 and 2013—OR=0.7 (P<0.01).
Patients who changed hospitals between HSCT and death were less likely to receive an intense intervention than patients who stayed at the same hospital. The OR was 0.3 if they transferred to a community hospital and 0.4 if they transferred to a specialty hospital (P<0.001 for both).
Patients living in rural areas were less likely than urban patients to receive a medically intense intervention—OR=0.6 (P<0.05).
“From our data, we understand there is a correlation with high-intensity end-of-life care in patients who die within one year after receiving a stem cell transplant, but we are still unsure if that was the care they wanted,” Dr. Johnston said.
“The findings suggest that, as oncologists, we need to start having end-of-life care conversations earlier with patients to determine if a high-intensity treatment plan is consistent with their goals or if a lower-intensity treatment plan is best. It’s not a one-size-fits-all approach in end-of-life care.”
This research was supported by Stanford University. One study author reported relationships with Corvus Pharmaceuticals, Shire Pharmaceuticals, and Adaptive Biotechnologies. All other authors reported no conflicts.
Adoptive T-cell therapy treats PML
Adoptive T-cell therapy has proven effective for treating progressive multifocal leukoencephalopathy (PML), according to research published in The New England Journal of Medicine.
Researchers observed substantial improvements in three PML patients infused with donor T cells targeting the BK virus.
Although one patient ultimately died, two had complete clearance of the JC virus and no clinical signs of PML after treatment.
“The JC and BK viruses are genetically similar and share proteins that can be targeted by the immune system,” said study author Katy Rezvani, MD, PhD, of The University of Texas MD Anderson Cancer Center in Houston.
“Because of these similarities, we hypothesized that T cells developed against BK virus may also be effective against JC virus infection.”
Dr. Rezvani’s team developed a novel approach for the generation of BK virus-specific T cells from healthy donors and established a bank of viral-specific T cells for immediate clinical use.
The researchers treated three patients with third-party, partially human leukocyte antigen (HLA)-matched, BK virus-specific T cells.
Patient 1 was a 32-year-old female with acute myeloid leukemia (AML) who previously received a double cord blood transplant.
Patient 2 was a 73-year-old female with JAK2-positive polycythemia rubra vera (PV) who had been treated with ruxolitinib.
Patient 3 was a 35-year-old man with AIDS who had discontinued highly active antiretroviral therapy due to side effects and who was no longer able to walk.
Following the first infusion, all three patients had a reduction in JC viral load in their cerebrospinal fluid. Viral loads dropped from:
- 700 to 78 copies in the AML patient
- 230,000 to 5,200 in the PV patient
- 4,300 to 1,300 in the AIDS patient.
“After infusion of viral-specific T cells, patients 1 and 3 had clinical improvement with significant reduction in JC virus in their cerebrospinal fluid,” Dr. Rezvani said.
“Both patients responded despite persistent T-cell immunodeficiency, supporting the concept that the response was mediated by the adoptively infused viral-specific T cells, and there were no infusion-related reactions.”
The AML patient received two additional infusions, which resulted in clearance of the virus in the cerebrospinal fluid and no signs of PML 27 months after the first infusion.
The PV patient received a second infusion that further reduced JC viral load, but no additional improvement was seen. The patient died 8 months after the first infusion.
The AIDS patient received additional infusions, resulting in complete clearance of the JC virus. This patient has regained mobility, and, 9 months after the first infusion, he is able to walk with a cane.
“We are encouraged that off-the-shelf, third-party, partially HLA-matched BK viral-specific T cells may provide a therapy for PML,” Dr. Rezvani said. “Further study in a larger group of patients is required to determine the success rate, durability, and longer-term adverse events with this treatment.”
This study was supported with funding from the Myelodysplastic Syndromes and Acute Myeloid Leukemia Moon Shot, part of MD Anderson’s Moon Shots Program, as well as the National Institutes of Health.
Adoptive T-cell therapy has proven effective for treating progressive multifocal leukoencephalopathy (PML), according to research published in The New England Journal of Medicine.
Researchers observed substantial improvements in three PML patients infused with donor T cells targeting the BK virus.
Although one patient ultimately died, two had complete clearance of the JC virus and no clinical signs of PML after treatment.
“The JC and BK viruses are genetically similar and share proteins that can be targeted by the immune system,” said study author Katy Rezvani, MD, PhD, of The University of Texas MD Anderson Cancer Center in Houston.
“Because of these similarities, we hypothesized that T cells developed against BK virus may also be effective against JC virus infection.”
Dr. Rezvani’s team developed a novel approach for the generation of BK virus-specific T cells from healthy donors and established a bank of viral-specific T cells for immediate clinical use.
The researchers treated three patients with third-party, partially human leukocyte antigen (HLA)-matched, BK virus-specific T cells.
Patient 1 was a 32-year-old female with acute myeloid leukemia (AML) who previously received a double cord blood transplant.
Patient 2 was a 73-year-old female with JAK2-positive polycythemia rubra vera (PV) who had been treated with ruxolitinib.
Patient 3 was a 35-year-old man with AIDS who had discontinued highly active antiretroviral therapy due to side effects and who was no longer able to walk.
Following the first infusion, all three patients had a reduction in JC viral load in their cerebrospinal fluid. Viral loads dropped from:
- 700 to 78 copies in the AML patient
- 230,000 to 5,200 in the PV patient
- 4,300 to 1,300 in the AIDS patient.
“After infusion of viral-specific T cells, patients 1 and 3 had clinical improvement with significant reduction in JC virus in their cerebrospinal fluid,” Dr. Rezvani said.
“Both patients responded despite persistent T-cell immunodeficiency, supporting the concept that the response was mediated by the adoptively infused viral-specific T cells, and there were no infusion-related reactions.”
The AML patient received two additional infusions, which resulted in clearance of the virus in the cerebrospinal fluid and no signs of PML 27 months after the first infusion.
The PV patient received a second infusion that further reduced JC viral load, but no additional improvement was seen. The patient died 8 months after the first infusion.
The AIDS patient received additional infusions, resulting in complete clearance of the JC virus. This patient has regained mobility, and, 9 months after the first infusion, he is able to walk with a cane.
“We are encouraged that off-the-shelf, third-party, partially HLA-matched BK viral-specific T cells may provide a therapy for PML,” Dr. Rezvani said. “Further study in a larger group of patients is required to determine the success rate, durability, and longer-term adverse events with this treatment.”
This study was supported with funding from the Myelodysplastic Syndromes and Acute Myeloid Leukemia Moon Shot, part of MD Anderson’s Moon Shots Program, as well as the National Institutes of Health.
Adoptive T-cell therapy has proven effective for treating progressive multifocal leukoencephalopathy (PML), according to research published in The New England Journal of Medicine.
Researchers observed substantial improvements in three PML patients infused with donor T cells targeting the BK virus.
Although one patient ultimately died, two had complete clearance of the JC virus and no clinical signs of PML after treatment.
“The JC and BK viruses are genetically similar and share proteins that can be targeted by the immune system,” said study author Katy Rezvani, MD, PhD, of The University of Texas MD Anderson Cancer Center in Houston.
“Because of these similarities, we hypothesized that T cells developed against BK virus may also be effective against JC virus infection.”
Dr. Rezvani’s team developed a novel approach for the generation of BK virus-specific T cells from healthy donors and established a bank of viral-specific T cells for immediate clinical use.
The researchers treated three patients with third-party, partially human leukocyte antigen (HLA)-matched, BK virus-specific T cells.
Patient 1 was a 32-year-old female with acute myeloid leukemia (AML) who previously received a double cord blood transplant.
Patient 2 was a 73-year-old female with JAK2-positive polycythemia rubra vera (PV) who had been treated with ruxolitinib.
Patient 3 was a 35-year-old man with AIDS who had discontinued highly active antiretroviral therapy due to side effects and who was no longer able to walk.
Following the first infusion, all three patients had a reduction in JC viral load in their cerebrospinal fluid. Viral loads dropped from:
- 700 to 78 copies in the AML patient
- 230,000 to 5,200 in the PV patient
- 4,300 to 1,300 in the AIDS patient.
“After infusion of viral-specific T cells, patients 1 and 3 had clinical improvement with significant reduction in JC virus in their cerebrospinal fluid,” Dr. Rezvani said.
“Both patients responded despite persistent T-cell immunodeficiency, supporting the concept that the response was mediated by the adoptively infused viral-specific T cells, and there were no infusion-related reactions.”
The AML patient received two additional infusions, which resulted in clearance of the virus in the cerebrospinal fluid and no signs of PML 27 months after the first infusion.
The PV patient received a second infusion that further reduced JC viral load, but no additional improvement was seen. The patient died 8 months after the first infusion.
The AIDS patient received additional infusions, resulting in complete clearance of the JC virus. This patient has regained mobility, and, 9 months after the first infusion, he is able to walk with a cane.
“We are encouraged that off-the-shelf, third-party, partially HLA-matched BK viral-specific T cells may provide a therapy for PML,” Dr. Rezvani said. “Further study in a larger group of patients is required to determine the success rate, durability, and longer-term adverse events with this treatment.”
This study was supported with funding from the Myelodysplastic Syndromes and Acute Myeloid Leukemia Moon Shot, part of MD Anderson’s Moon Shots Program, as well as the National Institutes of Health.
Dataset could reveal better therapies for AML
Researchers have released a dataset detailing the molecular makeup of tumor cells from more than 500 patients with acute myeloid leukemia (AML).
The team discovered mutations not previously observed in AML and found associations between mutations and responses to certain therapies.
For instance, AML cases with FLT3, NPM1, and DNMT3A mutations proved sensitive to the BTK inhibitor ibrutinib.
The researchers described their findings in Nature.
The team also made their dataset available via Vizome, an online data viewer. Other researchers can use Vizome to find out which targeted therapies might be most effective against specific subsets of AML cells.
“People can get online, search our database, and very quickly get answers to ‘Is this a good drug?’ or ‘Is there a patient population my drug can work in?’” said study author Brian Druker, MD, of Oregon Health & Science University (OHSU) in Portland, Oregon.
Newly identified mutations
For this study, part of the Beat AML initiative, Dr. Druker and his colleagues performed whole-exome and RNA sequencing on 672 samples from 562 AML patients.
The team identified mutations in 11 genes that were called in 1% or more of patients in this dataset but had not been observed in previous AML sequencing studies. The genes were:
- CUB and Sushi multiple domains 2 (CSMD2)
- NAC alpha domain containing (NACAD)
- Teneurin transmembrane protein 2 (TENM2)
- Aggrecan (ACAN)
- ADAM metallopeptidase with thrombospondin type 1 motif 7 (ADAMTS7)
- Immunoglobulin-like and fibronectin type III domain containing 1 (IGFN1)
- Neurobeachin-like 2 (NBEAL2)
- Poly(U) binding splicing factor 60 (PUF60)
- Zinc-finger protein 687 (ZNF687)
- Cadherin EGF LAG sevenpass G-type receptor 2 (CELSR2)
- Glutamate ionotropic receptor NMDA type subunit 2B (GRIN2B).
Testing therapies
The researchers also assessed how AML cells from 409 of the patient samples responded to each of 122 targeted therapies.
The team found that mutations in TP53, ASXL1, NRAS, and KRAS caused “a broad pattern of drug resistance.”
However, cases with TP53 mutations were sensitive to elesclomol (a drug that targets cancer cell metabolism), cases with ASXL1 mutations were sensitive to the HDAC inhibitor panobinostat, and cases with KRAS/NRAS mutations were sensitive to MAPK inhibitors (with NRAS-mutated cases demonstrating greater sensitivity).
The researchers also found that IDH2 mutations “conferred sensitivity to a broad spectrum of drugs,” but IDH1 mutations were associated with resistance to most drugs.
As previously mentioned, the researchers found a significant association between mutations in FLT3, NPM1, and DNMT3A and sensitivity to ibrutinib. However, the team found that cases with DNMT3A mutations alone or mutations in DNMT3A and FLT3 were not significantly different from cases with wild-type genes.
On the other hand, cases with FLT3-ITD alone or any combination with a mutation in NPM1 (including mutations in all three genes) were significantly more sensitive to ibrutinib than cases with wild-type genes.
Cases with FLT3-ITD and mutations in NPM1 were sensitive to another kinase inhibitor, entospletinib, as well.
The researchers also found that mutations in both BCOR and RUNX1 correlated with increased sensitivity to four JAK inhibitors—momelotinib, ruxolitinib, tofacitinib, and JAK inhibitor I.
However, cases with BCOR mutations alone or mutations in BCOR and DNMT3A or SRSF2 showed no difference in sensitivity to the JAK inhibitors from cases with wild-type genes.
Next steps
“We’re just starting to scratch the surface of what we can do when we analyze the data,” Dr. Druker said. “The real power comes when you start to integrate all that data. You can analyze what drug worked and why it worked.”
In fact, the researchers are already developing and initiating clinical trials to test hypotheses generated by this study.
“You can start to sense some momentum building with new, better therapeutics for AML patients, and, hopefully, this dataset will help fuel that momentum even further,” said study author Jeff Tyner, PhD, of the OHSU School of Medicine.
“We want to parlay this information into clinical trials as much as we can, and we also want the broader community to use this dataset to accelerate their own work.”
Funding for the current study was provided by grants from The Leukemia & Lymphoma Society, the National Cancer Institute, the National Library of Medicine, and other groups.
Researchers have released a dataset detailing the molecular makeup of tumor cells from more than 500 patients with acute myeloid leukemia (AML).
The team discovered mutations not previously observed in AML and found associations between mutations and responses to certain therapies.
For instance, AML cases with FLT3, NPM1, and DNMT3A mutations proved sensitive to the BTK inhibitor ibrutinib.
The researchers described their findings in Nature.
The team also made their dataset available via Vizome, an online data viewer. Other researchers can use Vizome to find out which targeted therapies might be most effective against specific subsets of AML cells.
“People can get online, search our database, and very quickly get answers to ‘Is this a good drug?’ or ‘Is there a patient population my drug can work in?’” said study author Brian Druker, MD, of Oregon Health & Science University (OHSU) in Portland, Oregon.
Newly identified mutations
For this study, part of the Beat AML initiative, Dr. Druker and his colleagues performed whole-exome and RNA sequencing on 672 samples from 562 AML patients.
The team identified mutations in 11 genes that were called in 1% or more of patients in this dataset but had not been observed in previous AML sequencing studies. The genes were:
- CUB and Sushi multiple domains 2 (CSMD2)
- NAC alpha domain containing (NACAD)
- Teneurin transmembrane protein 2 (TENM2)
- Aggrecan (ACAN)
- ADAM metallopeptidase with thrombospondin type 1 motif 7 (ADAMTS7)
- Immunoglobulin-like and fibronectin type III domain containing 1 (IGFN1)
- Neurobeachin-like 2 (NBEAL2)
- Poly(U) binding splicing factor 60 (PUF60)
- Zinc-finger protein 687 (ZNF687)
- Cadherin EGF LAG sevenpass G-type receptor 2 (CELSR2)
- Glutamate ionotropic receptor NMDA type subunit 2B (GRIN2B).
Testing therapies
The researchers also assessed how AML cells from 409 of the patient samples responded to each of 122 targeted therapies.
The team found that mutations in TP53, ASXL1, NRAS, and KRAS caused “a broad pattern of drug resistance.”
However, cases with TP53 mutations were sensitive to elesclomol (a drug that targets cancer cell metabolism), cases with ASXL1 mutations were sensitive to the HDAC inhibitor panobinostat, and cases with KRAS/NRAS mutations were sensitive to MAPK inhibitors (with NRAS-mutated cases demonstrating greater sensitivity).
The researchers also found that IDH2 mutations “conferred sensitivity to a broad spectrum of drugs,” but IDH1 mutations were associated with resistance to most drugs.
As previously mentioned, the researchers found a significant association between mutations in FLT3, NPM1, and DNMT3A and sensitivity to ibrutinib. However, the team found that cases with DNMT3A mutations alone or mutations in DNMT3A and FLT3 were not significantly different from cases with wild-type genes.
On the other hand, cases with FLT3-ITD alone or any combination with a mutation in NPM1 (including mutations in all three genes) were significantly more sensitive to ibrutinib than cases with wild-type genes.
Cases with FLT3-ITD and mutations in NPM1 were sensitive to another kinase inhibitor, entospletinib, as well.
The researchers also found that mutations in both BCOR and RUNX1 correlated with increased sensitivity to four JAK inhibitors—momelotinib, ruxolitinib, tofacitinib, and JAK inhibitor I.
However, cases with BCOR mutations alone or mutations in BCOR and DNMT3A or SRSF2 showed no difference in sensitivity to the JAK inhibitors from cases with wild-type genes.
Next steps
“We’re just starting to scratch the surface of what we can do when we analyze the data,” Dr. Druker said. “The real power comes when you start to integrate all that data. You can analyze what drug worked and why it worked.”
In fact, the researchers are already developing and initiating clinical trials to test hypotheses generated by this study.
“You can start to sense some momentum building with new, better therapeutics for AML patients, and, hopefully, this dataset will help fuel that momentum even further,” said study author Jeff Tyner, PhD, of the OHSU School of Medicine.
“We want to parlay this information into clinical trials as much as we can, and we also want the broader community to use this dataset to accelerate their own work.”
Funding for the current study was provided by grants from The Leukemia & Lymphoma Society, the National Cancer Institute, the National Library of Medicine, and other groups.
Researchers have released a dataset detailing the molecular makeup of tumor cells from more than 500 patients with acute myeloid leukemia (AML).
The team discovered mutations not previously observed in AML and found associations between mutations and responses to certain therapies.
For instance, AML cases with FLT3, NPM1, and DNMT3A mutations proved sensitive to the BTK inhibitor ibrutinib.
The researchers described their findings in Nature.
The team also made their dataset available via Vizome, an online data viewer. Other researchers can use Vizome to find out which targeted therapies might be most effective against specific subsets of AML cells.
“People can get online, search our database, and very quickly get answers to ‘Is this a good drug?’ or ‘Is there a patient population my drug can work in?’” said study author Brian Druker, MD, of Oregon Health & Science University (OHSU) in Portland, Oregon.
Newly identified mutations
For this study, part of the Beat AML initiative, Dr. Druker and his colleagues performed whole-exome and RNA sequencing on 672 samples from 562 AML patients.
The team identified mutations in 11 genes that were called in 1% or more of patients in this dataset but had not been observed in previous AML sequencing studies. The genes were:
- CUB and Sushi multiple domains 2 (CSMD2)
- NAC alpha domain containing (NACAD)
- Teneurin transmembrane protein 2 (TENM2)
- Aggrecan (ACAN)
- ADAM metallopeptidase with thrombospondin type 1 motif 7 (ADAMTS7)
- Immunoglobulin-like and fibronectin type III domain containing 1 (IGFN1)
- Neurobeachin-like 2 (NBEAL2)
- Poly(U) binding splicing factor 60 (PUF60)
- Zinc-finger protein 687 (ZNF687)
- Cadherin EGF LAG sevenpass G-type receptor 2 (CELSR2)
- Glutamate ionotropic receptor NMDA type subunit 2B (GRIN2B).
Testing therapies
The researchers also assessed how AML cells from 409 of the patient samples responded to each of 122 targeted therapies.
The team found that mutations in TP53, ASXL1, NRAS, and KRAS caused “a broad pattern of drug resistance.”
However, cases with TP53 mutations were sensitive to elesclomol (a drug that targets cancer cell metabolism), cases with ASXL1 mutations were sensitive to the HDAC inhibitor panobinostat, and cases with KRAS/NRAS mutations were sensitive to MAPK inhibitors (with NRAS-mutated cases demonstrating greater sensitivity).
The researchers also found that IDH2 mutations “conferred sensitivity to a broad spectrum of drugs,” but IDH1 mutations were associated with resistance to most drugs.
As previously mentioned, the researchers found a significant association between mutations in FLT3, NPM1, and DNMT3A and sensitivity to ibrutinib. However, the team found that cases with DNMT3A mutations alone or mutations in DNMT3A and FLT3 were not significantly different from cases with wild-type genes.
On the other hand, cases with FLT3-ITD alone or any combination with a mutation in NPM1 (including mutations in all three genes) were significantly more sensitive to ibrutinib than cases with wild-type genes.
Cases with FLT3-ITD and mutations in NPM1 were sensitive to another kinase inhibitor, entospletinib, as well.
The researchers also found that mutations in both BCOR and RUNX1 correlated with increased sensitivity to four JAK inhibitors—momelotinib, ruxolitinib, tofacitinib, and JAK inhibitor I.
However, cases with BCOR mutations alone or mutations in BCOR and DNMT3A or SRSF2 showed no difference in sensitivity to the JAK inhibitors from cases with wild-type genes.
Next steps
“We’re just starting to scratch the surface of what we can do when we analyze the data,” Dr. Druker said. “The real power comes when you start to integrate all that data. You can analyze what drug worked and why it worked.”
In fact, the researchers are already developing and initiating clinical trials to test hypotheses generated by this study.
“You can start to sense some momentum building with new, better therapeutics for AML patients, and, hopefully, this dataset will help fuel that momentum even further,” said study author Jeff Tyner, PhD, of the OHSU School of Medicine.
“We want to parlay this information into clinical trials as much as we can, and we also want the broader community to use this dataset to accelerate their own work.”
Funding for the current study was provided by grants from The Leukemia & Lymphoma Society, the National Cancer Institute, the National Library of Medicine, and other groups.
Researchers consider R/R ALL drugs in the first-line setting
CHICAGO – Novel antibodies are improving outcomes in relapsed and refractory acute lymphoblastic leukemia (ALL), and the hope is that they will also show benefit in the up-front treatment setting and thereby improve overall outcomes, according to Anjali Advani, MD.
“It has been a really exciting time in ALL because several drugs have now been FDA approved: blinatumomab, inotuzumab, and now – for patients who are less than 26 years of age – we actually have CAR [chimeric antigen receptor] T cells that have been approved,” Dr. Advani, a hematologist and director of the inpatient leukemia program at the Cleveland Clinic said at the American Society of Hematology Meeting on Hematologic Malignancies.
At the time of relapse, however, the only known cure is allogeneic bone marrow transplant. That may change as more data regarding CAR T cells become available, but the typical goal at this time is to get patients into remission and then to transplant, she said.
Blinatumomab
“Blinatumomab is a very interesting antibody,” Dr. Advani said, explaining that it is a bispecific, T cell–engaging antibody with an anti-CD3 arm that engages the T cell and an anti-CD19 antibody that engages the B lymphoblast.
“Basically this drug then acts as a bridge between the lymphoblast and the T cell to lead to proliferation of the cytotoxic T cell and apoptosis of the lymphoblast,” she said. “It’s interesting because it’s an antibody but it actually works through the immune system through the T cells.”
The largest study to date of blinatumomab in the relapsed/refractory ALL setting showed a 43% complete remission (CR) or CR with partial hematological recovery of peripheral blood counts (CRi) in 189 treated patients with Philadelphia chromosome–negative ALL. It also demonstrated and a 39% rate of salvage status 2 or higher, she said, noting that the response was impressive given that about 30% of participants had a prior transplant (Lancet. 2015 Jan 1;16[1]:57-66).
Of the responders, 40% went on to allogeneic transplant. This was a “fairly impressive” rate given the 30% prior-transplant rate, Dr. Advani said.
“There also was a high minimal residual disease response in those patients achieving CR,” she said, adding that the only significant predictor of response was bone marrow blast count; patients with 50% or more blasts in the bone marrow had a reduced likelihood of responding to blinatumomab.
The agent was approved by the Food and Drug Administration in December 2014 based on these phase 2 findings.
Adverse events mainly included toxicities that are expected in leukemia patients; the most frequent were febrile neutropenia, neutropenia, and anemia. Two patients developed cytokine release syndrome, and about half of the blinatumomab-treated patients experienced neurological events, although the majority of those were grade 1 or 2 and were easily manageable, she noted.
Blinatumomab was further evaluated in the phase 3 TOWER study (NCT02013167), which compared it with standard-of-care chemotherapy regimens. This study showed much higher response rates with blinatumomab than with the chemotherapy regimens (CR with full, partial, or incomplete hematologic recovery, 44% vs. 25%, respectively), Dr. Advani said (N Engl J Med. 2017 Mar 2;376[9]:836-47).
“The main things to remember [are that blinatumomab is] generally very well tolerated and it has been shown to be superior over standard chemotherapy,” she said. “I think it’s a very good drug to use as a bridge to transplant.”
One setting where blinatumomab perhaps should not be used is in patients with central nervous system disease, she noted.
“There is some concern, at least theoretically, that if you have to use concurrent intrathecal chemo along with blinatumomab, there could be some neurotoxicity,” Dr. Advani said, adding that there are no clear data in that setting because patients with CNS disease were not included in the trials.
Patients with high tumor burden may also be poor candidates for blinatumomab because they tend to have lower response rates.
“That doesn’t mean you can’t use it, but you have to kind of think about what the best option would be,” she said.
Additionally, patients treated with CAR T-cell therapy may develop CD19 loss or CD19-negative disease, and blinatumomab should be avoided in these patients.
“The nice thing ... is you don’t have to worry about veno-occlusive disease [VOD] in patients who are proceeding to transplant,” she said, explaining that no increased risk of VOD was seen in these trials.
Inotuzumab
Inotuzumab, which was approved in 2017, differs from blinatumomab in that it is an anti-CD22-calicheamicin conjugate; however, it also showed high response rates in the initial phase 2 trial in relapsed/refractory ALL. The overall response rate was 57%, with 18% achieving a complete response and 63% achieving complete molecular remission.
Of 49 treated patients, 22 patients proceeded to allogeneic transplant, and 5 of those developed VOD.
“Interestingly, four out of five of these patients had received a clofarabine-based preparative regimen, and this likely explains why there was a higher risk of VOD in this study,” she said, noting that the VOD risk has been lower in subsequent studies of inotuzumab.
The international INO-VATE ALL study (NCT01564784) that led to FDA approval was similar in design to the TOWER study in that it compared inotuzumab with standard chemotherapy regimens, and response rates were clearly higher (81% vs. 33%) with inotuzumab (N Engl J Med. 2016 Aug 25;375[8]:740-53).
The VOD risk in the INO-VATE trial was 11%, and it seemed to be higher in those who received dual alkylator–conditioning regimens, which are commonly used in Europe.
Longer-term outcomes after transplant in INO-VATE participants show that median survival has not been reached.
“It’s encouraging that with longer follow-up these patients actually look like they’re doing well,” Dr. Advani said, adding that inotuzumab is a good treatment option for relapsed patients with high disease burden or with CNS disease.
The continuous hookup required for this treatment may be problematic for some younger and older patients, but it is generally not an issue, she noted.
It is important, though, to give as few cycles prior to transplant as possible and to “really think about the preparative regimen to decrease the risk of VOD.”
CAR T-cell therapy
As for CAR T-cell therapy in the relapsed/refractory ALL setting, tisagenlecleucel was approved in 2017 for those up to age 25 years with B-cell precursor ALL that is refractory or in second or later relapse.
Approval was based on a single-arm trial of 63 patients with relapsed or refractory pediatric precursor B-cell ALL, including 35 patients who had prior transplant. The confirmed overall remission rate was 82%, with a 63% CR rate and 19% CRi rate.
“This is a very exciting area,” Dr. Advani said. “There are multiple trials being done in adults with ALL to really look at the older subgroup of patients.”
Overall outcomes
“These treatments we have now really seem to be effective in the relapse setting, but the problem is that once patients relapse and then go to transplant, their overall survival is still poor,” Dr. Advani said. “So the question is how can we improve the up-front treatment of patients so that hopefully they don’t relapse, and hopefully we also can send a smaller number of patients to transplant.”
Two trials seek to address this, she said.
The A041501 study (NCT03150693) is comparing C10403 chemotherapy with C10403 induction followed by two cycles of inotuzumab before continuing with chemotherapy in adults under age 40 years with previously untreated B ALL.
The primary objective is improved 3-year event-free survival, she said, adding that minimal residual disease (MRD) testing will be used and that CD20-positive patients will receive rituximab, as is now standard.
The phase 3 E1910 study (NCT02003222) is evaluating up-front blinatumomab in patients aged 30-70 years with newly diagnosed BCR-ABL–negative B-lineage ALL. This trial was complicated by the recent approval of blinatumomab for MRD-positive disease, which rendered randomization of MRD-positive patients unethical. MRD-negative patients will be randomized, however.
“The hope is that, by incorporating blinatumomab up front, this will again improve outcomes for patients,” she said.
Dr. Advani reported consultancy for Pfizer; research funding from Genzyme, Novartis, Pfizer, and Sigma Tau; and honoraria from Genzyme, Pfizer, and Sigma Tau. She is also on the speakers bureau for Sigma Tau.
CHICAGO – Novel antibodies are improving outcomes in relapsed and refractory acute lymphoblastic leukemia (ALL), and the hope is that they will also show benefit in the up-front treatment setting and thereby improve overall outcomes, according to Anjali Advani, MD.
“It has been a really exciting time in ALL because several drugs have now been FDA approved: blinatumomab, inotuzumab, and now – for patients who are less than 26 years of age – we actually have CAR [chimeric antigen receptor] T cells that have been approved,” Dr. Advani, a hematologist and director of the inpatient leukemia program at the Cleveland Clinic said at the American Society of Hematology Meeting on Hematologic Malignancies.
At the time of relapse, however, the only known cure is allogeneic bone marrow transplant. That may change as more data regarding CAR T cells become available, but the typical goal at this time is to get patients into remission and then to transplant, she said.
Blinatumomab
“Blinatumomab is a very interesting antibody,” Dr. Advani said, explaining that it is a bispecific, T cell–engaging antibody with an anti-CD3 arm that engages the T cell and an anti-CD19 antibody that engages the B lymphoblast.
“Basically this drug then acts as a bridge between the lymphoblast and the T cell to lead to proliferation of the cytotoxic T cell and apoptosis of the lymphoblast,” she said. “It’s interesting because it’s an antibody but it actually works through the immune system through the T cells.”
The largest study to date of blinatumomab in the relapsed/refractory ALL setting showed a 43% complete remission (CR) or CR with partial hematological recovery of peripheral blood counts (CRi) in 189 treated patients with Philadelphia chromosome–negative ALL. It also demonstrated and a 39% rate of salvage status 2 or higher, she said, noting that the response was impressive given that about 30% of participants had a prior transplant (Lancet. 2015 Jan 1;16[1]:57-66).
Of the responders, 40% went on to allogeneic transplant. This was a “fairly impressive” rate given the 30% prior-transplant rate, Dr. Advani said.
“There also was a high minimal residual disease response in those patients achieving CR,” she said, adding that the only significant predictor of response was bone marrow blast count; patients with 50% or more blasts in the bone marrow had a reduced likelihood of responding to blinatumomab.
The agent was approved by the Food and Drug Administration in December 2014 based on these phase 2 findings.
Adverse events mainly included toxicities that are expected in leukemia patients; the most frequent were febrile neutropenia, neutropenia, and anemia. Two patients developed cytokine release syndrome, and about half of the blinatumomab-treated patients experienced neurological events, although the majority of those were grade 1 or 2 and were easily manageable, she noted.
Blinatumomab was further evaluated in the phase 3 TOWER study (NCT02013167), which compared it with standard-of-care chemotherapy regimens. This study showed much higher response rates with blinatumomab than with the chemotherapy regimens (CR with full, partial, or incomplete hematologic recovery, 44% vs. 25%, respectively), Dr. Advani said (N Engl J Med. 2017 Mar 2;376[9]:836-47).
“The main things to remember [are that blinatumomab is] generally very well tolerated and it has been shown to be superior over standard chemotherapy,” she said. “I think it’s a very good drug to use as a bridge to transplant.”
One setting where blinatumomab perhaps should not be used is in patients with central nervous system disease, she noted.
“There is some concern, at least theoretically, that if you have to use concurrent intrathecal chemo along with blinatumomab, there could be some neurotoxicity,” Dr. Advani said, adding that there are no clear data in that setting because patients with CNS disease were not included in the trials.
Patients with high tumor burden may also be poor candidates for blinatumomab because they tend to have lower response rates.
“That doesn’t mean you can’t use it, but you have to kind of think about what the best option would be,” she said.
Additionally, patients treated with CAR T-cell therapy may develop CD19 loss or CD19-negative disease, and blinatumomab should be avoided in these patients.
“The nice thing ... is you don’t have to worry about veno-occlusive disease [VOD] in patients who are proceeding to transplant,” she said, explaining that no increased risk of VOD was seen in these trials.
Inotuzumab
Inotuzumab, which was approved in 2017, differs from blinatumomab in that it is an anti-CD22-calicheamicin conjugate; however, it also showed high response rates in the initial phase 2 trial in relapsed/refractory ALL. The overall response rate was 57%, with 18% achieving a complete response and 63% achieving complete molecular remission.
Of 49 treated patients, 22 patients proceeded to allogeneic transplant, and 5 of those developed VOD.
“Interestingly, four out of five of these patients had received a clofarabine-based preparative regimen, and this likely explains why there was a higher risk of VOD in this study,” she said, noting that the VOD risk has been lower in subsequent studies of inotuzumab.
The international INO-VATE ALL study (NCT01564784) that led to FDA approval was similar in design to the TOWER study in that it compared inotuzumab with standard chemotherapy regimens, and response rates were clearly higher (81% vs. 33%) with inotuzumab (N Engl J Med. 2016 Aug 25;375[8]:740-53).
The VOD risk in the INO-VATE trial was 11%, and it seemed to be higher in those who received dual alkylator–conditioning regimens, which are commonly used in Europe.
Longer-term outcomes after transplant in INO-VATE participants show that median survival has not been reached.
“It’s encouraging that with longer follow-up these patients actually look like they’re doing well,” Dr. Advani said, adding that inotuzumab is a good treatment option for relapsed patients with high disease burden or with CNS disease.
The continuous hookup required for this treatment may be problematic for some younger and older patients, but it is generally not an issue, she noted.
It is important, though, to give as few cycles prior to transplant as possible and to “really think about the preparative regimen to decrease the risk of VOD.”
CAR T-cell therapy
As for CAR T-cell therapy in the relapsed/refractory ALL setting, tisagenlecleucel was approved in 2017 for those up to age 25 years with B-cell precursor ALL that is refractory or in second or later relapse.
Approval was based on a single-arm trial of 63 patients with relapsed or refractory pediatric precursor B-cell ALL, including 35 patients who had prior transplant. The confirmed overall remission rate was 82%, with a 63% CR rate and 19% CRi rate.
“This is a very exciting area,” Dr. Advani said. “There are multiple trials being done in adults with ALL to really look at the older subgroup of patients.”
Overall outcomes
“These treatments we have now really seem to be effective in the relapse setting, but the problem is that once patients relapse and then go to transplant, their overall survival is still poor,” Dr. Advani said. “So the question is how can we improve the up-front treatment of patients so that hopefully they don’t relapse, and hopefully we also can send a smaller number of patients to transplant.”
Two trials seek to address this, she said.
The A041501 study (NCT03150693) is comparing C10403 chemotherapy with C10403 induction followed by two cycles of inotuzumab before continuing with chemotherapy in adults under age 40 years with previously untreated B ALL.
The primary objective is improved 3-year event-free survival, she said, adding that minimal residual disease (MRD) testing will be used and that CD20-positive patients will receive rituximab, as is now standard.
The phase 3 E1910 study (NCT02003222) is evaluating up-front blinatumomab in patients aged 30-70 years with newly diagnosed BCR-ABL–negative B-lineage ALL. This trial was complicated by the recent approval of blinatumomab for MRD-positive disease, which rendered randomization of MRD-positive patients unethical. MRD-negative patients will be randomized, however.
“The hope is that, by incorporating blinatumomab up front, this will again improve outcomes for patients,” she said.
Dr. Advani reported consultancy for Pfizer; research funding from Genzyme, Novartis, Pfizer, and Sigma Tau; and honoraria from Genzyme, Pfizer, and Sigma Tau. She is also on the speakers bureau for Sigma Tau.
CHICAGO – Novel antibodies are improving outcomes in relapsed and refractory acute lymphoblastic leukemia (ALL), and the hope is that they will also show benefit in the up-front treatment setting and thereby improve overall outcomes, according to Anjali Advani, MD.
“It has been a really exciting time in ALL because several drugs have now been FDA approved: blinatumomab, inotuzumab, and now – for patients who are less than 26 years of age – we actually have CAR [chimeric antigen receptor] T cells that have been approved,” Dr. Advani, a hematologist and director of the inpatient leukemia program at the Cleveland Clinic said at the American Society of Hematology Meeting on Hematologic Malignancies.
At the time of relapse, however, the only known cure is allogeneic bone marrow transplant. That may change as more data regarding CAR T cells become available, but the typical goal at this time is to get patients into remission and then to transplant, she said.
Blinatumomab
“Blinatumomab is a very interesting antibody,” Dr. Advani said, explaining that it is a bispecific, T cell–engaging antibody with an anti-CD3 arm that engages the T cell and an anti-CD19 antibody that engages the B lymphoblast.
“Basically this drug then acts as a bridge between the lymphoblast and the T cell to lead to proliferation of the cytotoxic T cell and apoptosis of the lymphoblast,” she said. “It’s interesting because it’s an antibody but it actually works through the immune system through the T cells.”
The largest study to date of blinatumomab in the relapsed/refractory ALL setting showed a 43% complete remission (CR) or CR with partial hematological recovery of peripheral blood counts (CRi) in 189 treated patients with Philadelphia chromosome–negative ALL. It also demonstrated and a 39% rate of salvage status 2 or higher, she said, noting that the response was impressive given that about 30% of participants had a prior transplant (Lancet. 2015 Jan 1;16[1]:57-66).
Of the responders, 40% went on to allogeneic transplant. This was a “fairly impressive” rate given the 30% prior-transplant rate, Dr. Advani said.
“There also was a high minimal residual disease response in those patients achieving CR,” she said, adding that the only significant predictor of response was bone marrow blast count; patients with 50% or more blasts in the bone marrow had a reduced likelihood of responding to blinatumomab.
The agent was approved by the Food and Drug Administration in December 2014 based on these phase 2 findings.
Adverse events mainly included toxicities that are expected in leukemia patients; the most frequent were febrile neutropenia, neutropenia, and anemia. Two patients developed cytokine release syndrome, and about half of the blinatumomab-treated patients experienced neurological events, although the majority of those were grade 1 or 2 and were easily manageable, she noted.
Blinatumomab was further evaluated in the phase 3 TOWER study (NCT02013167), which compared it with standard-of-care chemotherapy regimens. This study showed much higher response rates with blinatumomab than with the chemotherapy regimens (CR with full, partial, or incomplete hematologic recovery, 44% vs. 25%, respectively), Dr. Advani said (N Engl J Med. 2017 Mar 2;376[9]:836-47).
“The main things to remember [are that blinatumomab is] generally very well tolerated and it has been shown to be superior over standard chemotherapy,” she said. “I think it’s a very good drug to use as a bridge to transplant.”
One setting where blinatumomab perhaps should not be used is in patients with central nervous system disease, she noted.
“There is some concern, at least theoretically, that if you have to use concurrent intrathecal chemo along with blinatumomab, there could be some neurotoxicity,” Dr. Advani said, adding that there are no clear data in that setting because patients with CNS disease were not included in the trials.
Patients with high tumor burden may also be poor candidates for blinatumomab because they tend to have lower response rates.
“That doesn’t mean you can’t use it, but you have to kind of think about what the best option would be,” she said.
Additionally, patients treated with CAR T-cell therapy may develop CD19 loss or CD19-negative disease, and blinatumomab should be avoided in these patients.
“The nice thing ... is you don’t have to worry about veno-occlusive disease [VOD] in patients who are proceeding to transplant,” she said, explaining that no increased risk of VOD was seen in these trials.
Inotuzumab
Inotuzumab, which was approved in 2017, differs from blinatumomab in that it is an anti-CD22-calicheamicin conjugate; however, it also showed high response rates in the initial phase 2 trial in relapsed/refractory ALL. The overall response rate was 57%, with 18% achieving a complete response and 63% achieving complete molecular remission.
Of 49 treated patients, 22 patients proceeded to allogeneic transplant, and 5 of those developed VOD.
“Interestingly, four out of five of these patients had received a clofarabine-based preparative regimen, and this likely explains why there was a higher risk of VOD in this study,” she said, noting that the VOD risk has been lower in subsequent studies of inotuzumab.
The international INO-VATE ALL study (NCT01564784) that led to FDA approval was similar in design to the TOWER study in that it compared inotuzumab with standard chemotherapy regimens, and response rates were clearly higher (81% vs. 33%) with inotuzumab (N Engl J Med. 2016 Aug 25;375[8]:740-53).
The VOD risk in the INO-VATE trial was 11%, and it seemed to be higher in those who received dual alkylator–conditioning regimens, which are commonly used in Europe.
Longer-term outcomes after transplant in INO-VATE participants show that median survival has not been reached.
“It’s encouraging that with longer follow-up these patients actually look like they’re doing well,” Dr. Advani said, adding that inotuzumab is a good treatment option for relapsed patients with high disease burden or with CNS disease.
The continuous hookup required for this treatment may be problematic for some younger and older patients, but it is generally not an issue, she noted.
It is important, though, to give as few cycles prior to transplant as possible and to “really think about the preparative regimen to decrease the risk of VOD.”
CAR T-cell therapy
As for CAR T-cell therapy in the relapsed/refractory ALL setting, tisagenlecleucel was approved in 2017 for those up to age 25 years with B-cell precursor ALL that is refractory or in second or later relapse.
Approval was based on a single-arm trial of 63 patients with relapsed or refractory pediatric precursor B-cell ALL, including 35 patients who had prior transplant. The confirmed overall remission rate was 82%, with a 63% CR rate and 19% CRi rate.
“This is a very exciting area,” Dr. Advani said. “There are multiple trials being done in adults with ALL to really look at the older subgroup of patients.”
Overall outcomes
“These treatments we have now really seem to be effective in the relapse setting, but the problem is that once patients relapse and then go to transplant, their overall survival is still poor,” Dr. Advani said. “So the question is how can we improve the up-front treatment of patients so that hopefully they don’t relapse, and hopefully we also can send a smaller number of patients to transplant.”
Two trials seek to address this, she said.
The A041501 study (NCT03150693) is comparing C10403 chemotherapy with C10403 induction followed by two cycles of inotuzumab before continuing with chemotherapy in adults under age 40 years with previously untreated B ALL.
The primary objective is improved 3-year event-free survival, she said, adding that minimal residual disease (MRD) testing will be used and that CD20-positive patients will receive rituximab, as is now standard.
The phase 3 E1910 study (NCT02003222) is evaluating up-front blinatumomab in patients aged 30-70 years with newly diagnosed BCR-ABL–negative B-lineage ALL. This trial was complicated by the recent approval of blinatumomab for MRD-positive disease, which rendered randomization of MRD-positive patients unethical. MRD-negative patients will be randomized, however.
“The hope is that, by incorporating blinatumomab up front, this will again improve outcomes for patients,” she said.
Dr. Advani reported consultancy for Pfizer; research funding from Genzyme, Novartis, Pfizer, and Sigma Tau; and honoraria from Genzyme, Pfizer, and Sigma Tau. She is also on the speakers bureau for Sigma Tau.
EXPERT ANALYSIS FROM MHM 2018
Ibrutinib plus obinutuzumab gets priority review in CLL/SLL
The Food and Drug Administration has granted priority review to an anti-CD20, chemotherapy-free combination – ibrutinib plus obinutuzumab – for the frontline treatment of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL).
The agency will review the combination in previously untreated adults.
Ibrutinib (Imbruvica) is already approved as a single agent for adults with CLL/SLL for all lines of therapy and in combination with bendamustine and rituximab. Obinutuzumab (Gazyva) has been approved for patients with previously untreated CLL, in combination with chlorambucil.
The current application, which is sponsored by Janssen and Pharmacyclics, is based on results from the phase 3 iLLUMINATE trial. Preliminary results announced by Janssen and Pharmacyclics showed that ibrutinib plus obinutuzumab had statistically significant better progression-free survival, compared with chlorambucil plus obinutuzumab, as assessed by an independent review committee.
Complete results from the trial will be presented at an upcoming medical meeting, according to the sponsors.
The Food and Drug Administration has granted priority review to an anti-CD20, chemotherapy-free combination – ibrutinib plus obinutuzumab – for the frontline treatment of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL).
The agency will review the combination in previously untreated adults.
Ibrutinib (Imbruvica) is already approved as a single agent for adults with CLL/SLL for all lines of therapy and in combination with bendamustine and rituximab. Obinutuzumab (Gazyva) has been approved for patients with previously untreated CLL, in combination with chlorambucil.
The current application, which is sponsored by Janssen and Pharmacyclics, is based on results from the phase 3 iLLUMINATE trial. Preliminary results announced by Janssen and Pharmacyclics showed that ibrutinib plus obinutuzumab had statistically significant better progression-free survival, compared with chlorambucil plus obinutuzumab, as assessed by an independent review committee.
Complete results from the trial will be presented at an upcoming medical meeting, according to the sponsors.
The Food and Drug Administration has granted priority review to an anti-CD20, chemotherapy-free combination – ibrutinib plus obinutuzumab – for the frontline treatment of chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL).
The agency will review the combination in previously untreated adults.
Ibrutinib (Imbruvica) is already approved as a single agent for adults with CLL/SLL for all lines of therapy and in combination with bendamustine and rituximab. Obinutuzumab (Gazyva) has been approved for patients with previously untreated CLL, in combination with chlorambucil.
The current application, which is sponsored by Janssen and Pharmacyclics, is based on results from the phase 3 iLLUMINATE trial. Preliminary results announced by Janssen and Pharmacyclics showed that ibrutinib plus obinutuzumab had statistically significant better progression-free survival, compared with chlorambucil plus obinutuzumab, as assessed by an independent review committee.
Complete results from the trial will be presented at an upcoming medical meeting, according to the sponsors.