FDA approves long-acting hemophilia B therapy

The US Food and Drug Administration (FDA) has approved Idelvion (Coagulation Factor IX [Recombinant], Albumin Fusion Protein) for the treatment of hemophilia B.

The product—a fusion protein linking recombinant coagulation factor IX with recombinant albumin—is intended for use in children and adults for routine prophylaxis to prevent or reduce the frequency of bleeding episodes, for on-demand control and prevention of bleeding episodes, and for the perioperative management of bleeding.

Appropriate patients age 12 and older can go up to 14 days between Idelvion infusions. This dosing interval has been achieved while maintaining high levels of factor IX activity—above 5% over 14 days at 75 IU/kg.

Idelvion is the first FDA-approved recombinant factor IX therapy that can extend the dosing interval up to 14 days.

Idelvion is expected to be available in the US later this month. The product is being developed by CSL Behring. For more details on the drug, see the full prescribing information.

Phase 3 trial

The FDA approved Idelvion based on results of the PROLONG-9FP clinical development program. PROLONG-9FP includes phase 1, 2, and 3 studies evaluating the safety and efficacy of Idelvion in adults and children (ages 1 to 61) with hemophilia B.

Data from the phase 3 study were recently published in Blood. This study included 63 previously treated male patients with severe hemophilia B. They had a mean age of 33 (range, 12 to 61).

The patients were divided into 2 groups. Group 1 (n=40) received routine prophylaxis with Idelvion once every 7 days for 26 weeks, followed by a 7-, 10- or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively.

Group 2 received on-demand treatment with Idelvion for bleeding episodes for 26 weeks (n=23) and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks (n=19).

The median annualized bleeding rate (ABR) was 2.0 in the prophylaxis arm (group 1) and 23.5 in the on-demand treatment arm (group 2). The median spontaneous ABRs were 0.0 and 17.0, respectively.

For patients in group 2, there was a significant reduction in median ABRs when patients switched from on-demand treatment to prophylaxis—19.22 and 1.58, respectively (P<0.0001). And there was a significant reduction in median spontaneous ABRs—15.43 and 0.00, respectively (P<0.0001).

Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection of Idelvion.

None of the patients developed inhibitors or experienced thromboembolic events, anaphylaxis, or life-threatening adverse events (AEs).

There were 347 treatment-emergent AEs reported in 54 (85.7%) patients. The most common were nasopharyngitis (25.4%), headache (23.8%), arthralgia (4.3%), and influenza (11.1%).

Eleven mild/moderate AEs in 5 patients (7.9%) were considered possibly related to Idelvion. Two patients discontinued treatment due to AEs—1 with hypersensitivity and 1 with headache.

The US Food and Drug Administration (FDA) has approved Idelvion (Coagulation Factor IX [Recombinant], Albumin Fusion Protein) for the treatment of hemophilia B.

The product—a fusion protein linking recombinant coagulation factor IX with recombinant albumin—is intended for use in children and adults for routine prophylaxis to prevent or reduce the frequency of bleeding episodes, for on-demand control and prevention of bleeding episodes, and for the perioperative management of bleeding.

Appropriate patients age 12 and older can go up to 14 days between Idelvion infusions. This dosing interval has been achieved while maintaining high levels of factor IX activity—above 5% over 14 days at 75 IU/kg.

Idelvion is the first FDA-approved recombinant factor IX therapy that can extend the dosing interval up to 14 days.

Idelvion is expected to be available in the US later this month. The product is being developed by CSL Behring. For more details on the drug, see the full prescribing information.

Phase 3 trial

The FDA approved Idelvion based on results of the PROLONG-9FP clinical development program. PROLONG-9FP includes phase 1, 2, and 3 studies evaluating the safety and efficacy of Idelvion in adults and children (ages 1 to 61) with hemophilia B.

Data from the phase 3 study were recently published in Blood. This study included 63 previously treated male patients with severe hemophilia B. They had a mean age of 33 (range, 12 to 61).

The patients were divided into 2 groups. Group 1 (n=40) received routine prophylaxis with Idelvion once every 7 days for 26 weeks, followed by a 7-, 10- or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively.

Group 2 received on-demand treatment with Idelvion for bleeding episodes for 26 weeks (n=23) and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks (n=19).

The median annualized bleeding rate (ABR) was 2.0 in the prophylaxis arm (group 1) and 23.5 in the on-demand treatment arm (group 2). The median spontaneous ABRs were 0.0 and 17.0, respectively.

For patients in group 2, there was a significant reduction in median ABRs when patients switched from on-demand treatment to prophylaxis—19.22 and 1.58, respectively (P<0.0001). And there was a significant reduction in median spontaneous ABRs—15.43 and 0.00, respectively (P<0.0001).

Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection of Idelvion.

None of the patients developed inhibitors or experienced thromboembolic events, anaphylaxis, or life-threatening adverse events (AEs).

There were 347 treatment-emergent AEs reported in 54 (85.7%) patients. The most common were nasopharyngitis (25.4%), headache (23.8%), arthralgia (4.3%), and influenza (11.1%).

Eleven mild/moderate AEs in 5 patients (7.9%) were considered possibly related to Idelvion. Two patients discontinued treatment due to AEs—1 with hypersensitivity and 1 with headache.

The US Food and Drug Administration (FDA) has approved Idelvion (Coagulation Factor IX [Recombinant], Albumin Fusion Protein) for the treatment of hemophilia B.

The product—a fusion protein linking recombinant coagulation factor IX with recombinant albumin—is intended for use in children and adults for routine prophylaxis to prevent or reduce the frequency of bleeding episodes, for on-demand control and prevention of bleeding episodes, and for the perioperative management of bleeding.

Appropriate patients age 12 and older can go up to 14 days between Idelvion infusions. This dosing interval has been achieved while maintaining high levels of factor IX activity—above 5% over 14 days at 75 IU/kg.

Idelvion is the first FDA-approved recombinant factor IX therapy that can extend the dosing interval up to 14 days.

Idelvion is expected to be available in the US later this month. The product is being developed by CSL Behring. For more details on the drug, see the full prescribing information.

Phase 3 trial

The FDA approved Idelvion based on results of the PROLONG-9FP clinical development program. PROLONG-9FP includes phase 1, 2, and 3 studies evaluating the safety and efficacy of Idelvion in adults and children (ages 1 to 61) with hemophilia B.

Data from the phase 3 study were recently published in Blood. This study included 63 previously treated male patients with severe hemophilia B. They had a mean age of 33 (range, 12 to 61).

The patients were divided into 2 groups. Group 1 (n=40) received routine prophylaxis with Idelvion once every 7 days for 26 weeks, followed by a 7-, 10- or 14-day prophylaxis regimen for a mean of 50, 38, or 51 weeks, respectively.

Group 2 received on-demand treatment with Idelvion for bleeding episodes for 26 weeks (n=23) and then switched to a 7-day prophylaxis regimen for a mean of 45 weeks (n=19).

The median annualized bleeding rate (ABR) was 2.0 in the prophylaxis arm (group 1) and 23.5 in the on-demand treatment arm (group 2). The median spontaneous ABRs were 0.0 and 17.0, respectively.

For patients in group 2, there was a significant reduction in median ABRs when patients switched from on-demand treatment to prophylaxis—19.22 and 1.58, respectively (P<0.0001). And there was a significant reduction in median spontaneous ABRs—15.43 and 0.00, respectively (P<0.0001).

Overall, 98.6% of bleeding episodes were treated successfully, including 93.6% that were treated with a single injection of Idelvion.

None of the patients developed inhibitors or experienced thromboembolic events, anaphylaxis, or life-threatening adverse events (AEs).

There were 347 treatment-emergent AEs reported in 54 (85.7%) patients. The most common were nasopharyngitis (25.4%), headache (23.8%), arthralgia (4.3%), and influenza (11.1%).

Eleven mild/moderate AEs in 5 patients (7.9%) were considered possibly related to Idelvion. Two patients discontinued treatment due to AEs—1 with hypersensitivity and 1 with headache.