Data suggest one BTK inhibitor could replace another

 

 

Attendees at the 2016

ASH Annual Meeting

 

SAN DIEGO—When patients with chronic lymphocytic leukemia (CLL) cannot tolerate one Bruton’s tyrosine kinase (BTK) inhibitor, they may do well on another, according to a presentation at the 2016 ASH Annual Meeting.

Researchers conducting a phase 1/2 study found that acalabrutinib was “well-tolerated” and demonstrated “promising activity” in patients intolerant to ibrutinib.

Seventy-nine percent of patients responded to acalabrutinib.

And although 36% of patients had a recurrence of an adverse event (AE) they experienced while on ibrutinib, none of the patients discontinued acalabrutinib due to AE recurrence.

Farrukh T. Awan, MD, of The Ohio State University in Columbus, Ohio, presented these results at the meeting as abstract 638.*

Dr Awan noted that integrating ibrutinib into standard CLL therapy has improved patient outcomes, but a lack of tolerability observed in some patients suggests that more selective BTK inhibition may be desirable.

“We know that around 10% to 20% of patients who are treated with ibrutinib would have to stop therapy because of an adverse event,” Dr Awan said. “Acalabrutinib is a highly selective, potent BTK inhibitor that has shown promising efficacy, and that [research] was published last year.”

In this ongoing, phase 1/2 study, Dr Awan and his colleagues are testing acalabrutinib in patients with CLL/small lymphocytic leukemia. The study has enrolled multiple cohorts of patients—relapsed/refractory, treatment-naïve, Richter’s transformation/prolymphocytic leukemia, and ibrutinib intolerant.

At this year’s ASH meeting, Dr Awan presented data on the 33 CLL patients who were ibrutinib intolerant. The patients’ median age was 64 (range, 50-82), 61% were male, 97% had an ECOG performance status of 0-1, 52% had Rai stage III-IV, and 31% had bulky disease.

The median number of prior therapies was 4 (range, 2-13), and 91% of patients had ibrutinib as their last therapy. The median duration of prior ibrutinib treatment was 11.5 months (range, 1-62), and the median time from ending ibrutinib to starting acalabrutinib was 47 days (range, 3-331 days).

Treatment and safety

Patients received acalabrutinib at 100 mg twice daily (n=30) or 200 mg daily (n=3) until disease progression or discontinuation for another reason. The patients’ median time on therapy was 12.2 months (range, 0.2-23.6 months).

Nine patients discontinued treatment—3 due to disease progression, 3 due to AEs, 2 due to an increase in BTK C481S mutation frequency in the peripheral blood and central nervous system involvement, and 1 due to physician decision (because the patient had concurrent hemophilia).

The 3 AEs that led to treatment discontinuation were fatal hemorrhagic stroke, fatal fungal infection, and metastatic endometrial cancer. All 3 events were considered unrelated to acalabrutinib.

Serious AEs occurred in 11 patients (33%). A serious AE that occurred in more than 1 patient was pneumonia (n=2).

The most common AEs were diarrhea (52%, grade 1-2), headache (39%, grade 1-2), cough (24%, grade 1-2), increased weight (24%, grade 1-2), nausea (21%, grade 1-2), contusion (18%, grade 1-2), ecchymosis (18%, grade 1-2), fatigue (18%, grade 1-2), hypertension (18% overall, 6% ≥ grade 3), pyrexia (18% overall, 3% ≥ grade 3), vomiting (18%, grade 1-2), myalgia (15% overall, 3% ≥ grade 3), rash (15%, grade 1-2), stomatitis (15%, grade 1-2), upper respiratory tract infection (15%, grade 1-2), and urinary tract infection (15%, grade 1-2).

AE recurrence

Twelve patients (36%) had a recurrence of ibrutinib-related AEs—a total of 16 events. Fourteen of these events either decreased in severity or were unchanged with acalabrutinib treatment.

The events without a change in severity were atrial fibrillation (n=1), fatigue (n=1), muscle spasms (n=1), myalgia (n=1), peripheral edema (n=1), panniculitis (n=1), and rash (n=1).

The events that decreased in severity were diarrhea (n=2), arthralgia (n=1), ecchymosis (n=1), fatigue (n=1), panniculitis (n=1), and rash (n=1).

The events that increased in severity were contusion (n=1, grade 1 to 2) and fatigue (n=1, grade 1 to 2).

None of the patients discontinued acalabrutinib due to AE recurrence.

Efficacy

Twenty-nine patients were evaluable for efficacy.

The overall response rate was 79% (n=23). One patient had a complete response (3%), 15 had a partial response (52%), and 7 had a partial response with lymphocytosis (24%). Six patients had stable disease (21%).

The median time to response was 1.9 months. Eighty-one percent of responding patients have a response duration of 12 months or longer.

The median progression-free survival has not been reached.

The research is sponsored by Acerta Pharma.

*Information presented at the meeting differs from the abstract.

 

 

Attendees at the 2016

ASH Annual Meeting

 

SAN DIEGO—When patients with chronic lymphocytic leukemia (CLL) cannot tolerate one Bruton’s tyrosine kinase (BTK) inhibitor, they may do well on another, according to a presentation at the 2016 ASH Annual Meeting.

Researchers conducting a phase 1/2 study found that acalabrutinib was “well-tolerated” and demonstrated “promising activity” in patients intolerant to ibrutinib.

Seventy-nine percent of patients responded to acalabrutinib.

And although 36% of patients had a recurrence of an adverse event (AE) they experienced while on ibrutinib, none of the patients discontinued acalabrutinib due to AE recurrence.

Farrukh T. Awan, MD, of The Ohio State University in Columbus, Ohio, presented these results at the meeting as abstract 638.*

Dr Awan noted that integrating ibrutinib into standard CLL therapy has improved patient outcomes, but a lack of tolerability observed in some patients suggests that more selective BTK inhibition may be desirable.

“We know that around 10% to 20% of patients who are treated with ibrutinib would have to stop therapy because of an adverse event,” Dr Awan said. “Acalabrutinib is a highly selective, potent BTK inhibitor that has shown promising efficacy, and that [research] was published last year.”

In this ongoing, phase 1/2 study, Dr Awan and his colleagues are testing acalabrutinib in patients with CLL/small lymphocytic leukemia. The study has enrolled multiple cohorts of patients—relapsed/refractory, treatment-naïve, Richter’s transformation/prolymphocytic leukemia, and ibrutinib intolerant.

At this year’s ASH meeting, Dr Awan presented data on the 33 CLL patients who were ibrutinib intolerant. The patients’ median age was 64 (range, 50-82), 61% were male, 97% had an ECOG performance status of 0-1, 52% had Rai stage III-IV, and 31% had bulky disease.

The median number of prior therapies was 4 (range, 2-13), and 91% of patients had ibrutinib as their last therapy. The median duration of prior ibrutinib treatment was 11.5 months (range, 1-62), and the median time from ending ibrutinib to starting acalabrutinib was 47 days (range, 3-331 days).

Treatment and safety

Patients received acalabrutinib at 100 mg twice daily (n=30) or 200 mg daily (n=3) until disease progression or discontinuation for another reason. The patients’ median time on therapy was 12.2 months (range, 0.2-23.6 months).

Nine patients discontinued treatment—3 due to disease progression, 3 due to AEs, 2 due to an increase in BTK C481S mutation frequency in the peripheral blood and central nervous system involvement, and 1 due to physician decision (because the patient had concurrent hemophilia).

The 3 AEs that led to treatment discontinuation were fatal hemorrhagic stroke, fatal fungal infection, and metastatic endometrial cancer. All 3 events were considered unrelated to acalabrutinib.

Serious AEs occurred in 11 patients (33%). A serious AE that occurred in more than 1 patient was pneumonia (n=2).

The most common AEs were diarrhea (52%, grade 1-2), headache (39%, grade 1-2), cough (24%, grade 1-2), increased weight (24%, grade 1-2), nausea (21%, grade 1-2), contusion (18%, grade 1-2), ecchymosis (18%, grade 1-2), fatigue (18%, grade 1-2), hypertension (18% overall, 6% ≥ grade 3), pyrexia (18% overall, 3% ≥ grade 3), vomiting (18%, grade 1-2), myalgia (15% overall, 3% ≥ grade 3), rash (15%, grade 1-2), stomatitis (15%, grade 1-2), upper respiratory tract infection (15%, grade 1-2), and urinary tract infection (15%, grade 1-2).

AE recurrence

Twelve patients (36%) had a recurrence of ibrutinib-related AEs—a total of 16 events. Fourteen of these events either decreased in severity or were unchanged with acalabrutinib treatment.

The events without a change in severity were atrial fibrillation (n=1), fatigue (n=1), muscle spasms (n=1), myalgia (n=1), peripheral edema (n=1), panniculitis (n=1), and rash (n=1).

The events that decreased in severity were diarrhea (n=2), arthralgia (n=1), ecchymosis (n=1), fatigue (n=1), panniculitis (n=1), and rash (n=1).

The events that increased in severity were contusion (n=1, grade 1 to 2) and fatigue (n=1, grade 1 to 2).

None of the patients discontinued acalabrutinib due to AE recurrence.

Efficacy

Twenty-nine patients were evaluable for efficacy.

The overall response rate was 79% (n=23). One patient had a complete response (3%), 15 had a partial response (52%), and 7 had a partial response with lymphocytosis (24%). Six patients had stable disease (21%).

The median time to response was 1.9 months. Eighty-one percent of responding patients have a response duration of 12 months or longer.

The median progression-free survival has not been reached.

The research is sponsored by Acerta Pharma.

*Information presented at the meeting differs from the abstract.

 

 

Attendees at the 2016

ASH Annual Meeting

 

SAN DIEGO—When patients with chronic lymphocytic leukemia (CLL) cannot tolerate one Bruton’s tyrosine kinase (BTK) inhibitor, they may do well on another, according to a presentation at the 2016 ASH Annual Meeting.

Researchers conducting a phase 1/2 study found that acalabrutinib was “well-tolerated” and demonstrated “promising activity” in patients intolerant to ibrutinib.

Seventy-nine percent of patients responded to acalabrutinib.

And although 36% of patients had a recurrence of an adverse event (AE) they experienced while on ibrutinib, none of the patients discontinued acalabrutinib due to AE recurrence.

Farrukh T. Awan, MD, of The Ohio State University in Columbus, Ohio, presented these results at the meeting as abstract 638.*

Dr Awan noted that integrating ibrutinib into standard CLL therapy has improved patient outcomes, but a lack of tolerability observed in some patients suggests that more selective BTK inhibition may be desirable.

“We know that around 10% to 20% of patients who are treated with ibrutinib would have to stop therapy because of an adverse event,” Dr Awan said. “Acalabrutinib is a highly selective, potent BTK inhibitor that has shown promising efficacy, and that [research] was published last year.”

In this ongoing, phase 1/2 study, Dr Awan and his colleagues are testing acalabrutinib in patients with CLL/small lymphocytic leukemia. The study has enrolled multiple cohorts of patients—relapsed/refractory, treatment-naïve, Richter’s transformation/prolymphocytic leukemia, and ibrutinib intolerant.

At this year’s ASH meeting, Dr Awan presented data on the 33 CLL patients who were ibrutinib intolerant. The patients’ median age was 64 (range, 50-82), 61% were male, 97% had an ECOG performance status of 0-1, 52% had Rai stage III-IV, and 31% had bulky disease.

The median number of prior therapies was 4 (range, 2-13), and 91% of patients had ibrutinib as their last therapy. The median duration of prior ibrutinib treatment was 11.5 months (range, 1-62), and the median time from ending ibrutinib to starting acalabrutinib was 47 days (range, 3-331 days).

Treatment and safety

Patients received acalabrutinib at 100 mg twice daily (n=30) or 200 mg daily (n=3) until disease progression or discontinuation for another reason. The patients’ median time on therapy was 12.2 months (range, 0.2-23.6 months).

Nine patients discontinued treatment—3 due to disease progression, 3 due to AEs, 2 due to an increase in BTK C481S mutation frequency in the peripheral blood and central nervous system involvement, and 1 due to physician decision (because the patient had concurrent hemophilia).

The 3 AEs that led to treatment discontinuation were fatal hemorrhagic stroke, fatal fungal infection, and metastatic endometrial cancer. All 3 events were considered unrelated to acalabrutinib.

Serious AEs occurred in 11 patients (33%). A serious AE that occurred in more than 1 patient was pneumonia (n=2).

The most common AEs were diarrhea (52%, grade 1-2), headache (39%, grade 1-2), cough (24%, grade 1-2), increased weight (24%, grade 1-2), nausea (21%, grade 1-2), contusion (18%, grade 1-2), ecchymosis (18%, grade 1-2), fatigue (18%, grade 1-2), hypertension (18% overall, 6% ≥ grade 3), pyrexia (18% overall, 3% ≥ grade 3), vomiting (18%, grade 1-2), myalgia (15% overall, 3% ≥ grade 3), rash (15%, grade 1-2), stomatitis (15%, grade 1-2), upper respiratory tract infection (15%, grade 1-2), and urinary tract infection (15%, grade 1-2).

AE recurrence

Twelve patients (36%) had a recurrence of ibrutinib-related AEs—a total of 16 events. Fourteen of these events either decreased in severity or were unchanged with acalabrutinib treatment.

The events without a change in severity were atrial fibrillation (n=1), fatigue (n=1), muscle spasms (n=1), myalgia (n=1), peripheral edema (n=1), panniculitis (n=1), and rash (n=1).

The events that decreased in severity were diarrhea (n=2), arthralgia (n=1), ecchymosis (n=1), fatigue (n=1), panniculitis (n=1), and rash (n=1).

The events that increased in severity were contusion (n=1, grade 1 to 2) and fatigue (n=1, grade 1 to 2).

None of the patients discontinued acalabrutinib due to AE recurrence.

Efficacy

Twenty-nine patients were evaluable for efficacy.

The overall response rate was 79% (n=23). One patient had a complete response (3%), 15 had a partial response (52%), and 7 had a partial response with lymphocytosis (24%). Six patients had stable disease (21%).

The median time to response was 1.9 months. Eighty-one percent of responding patients have a response duration of 12 months or longer.

The median progression-free survival has not been reached.

The research is sponsored by Acerta Pharma.

*Information presented at the meeting differs from the abstract.