Officials with the FDA today approved luspatercept-aamt (Reblozyl, Celgene) for the treatment of anemia in adult patients with beta thalassemia who require regular red blood cell (RBC) transfusions, according to a press release.

With this approval, luspatercept-aamt is the first FDA-approved erythroid maturation agent for anemia in beta thalassemia. Luspatercept-aamt is not indicated for use as a substitute for RBC transfusions in patients who require immediate correction of anemia.

Beta thalassemia, a rare and inherited blood disorder caused by a genetic defect in hemoglobin, is associated with ineffective erythropoiesis, which can lead to severe anemia, according to Celgene. Treatment options typically consistent of RBC transfusions, which have the potential to contribute to iron overload and cause serious complications, such as organ damage.

The approval is based on data from the phase 3 BELIEVE clinical trial, which evaluated the safety and efficacy of luspatercept-aamt for the treatment of anemia in adults with beta thalassemia who require regular RBC transfusions. A total of 336 patients received either luspatercept-aamt plus best supportive care (BSC) or a placebo plus BSC

Based on the results, the study achieved a clinically meaningful and statistically significant improvement in the primary endpoint. Among patients who were treated with luspatercept-aamt, 21.4% achieved a ≥33 reduction from baseline in RBC transfusion burden (with a reduction of at least 2 units) during weeks 13 to 24 after randomization, compared with 4.5% in the placebo arm (risk difference [95% CI]: 17.0 [10.4, 23.6], P<0.0001).

Key secondary points were also met, according to the findings. This included a transfusion burden reduction of at least 33% during weeks 37 to 48, which was achieved in 19.6% of patients in the luspatercept-aamt arm and 3.6% in the placebo arm (risk difference [95% CI]: 9.4 [5,13.7], P=0.0017), respectively.

Other efficacy endpoints included:
  • Transfusion burden reduction of ≥50% (with a decrease of at least 2 units) during weeks 13 to 24 and weeks 37 to 48.
  • A ≥50% reduction in transfusion burden in 7.6% of patients receiving luspatercept-aamt versus 1.8% of patients in the placebo arm at weeks 13 to 24 (risk difference [95% CI]: 5.8 [1.6, 10.1, P=0.0303), and 10.3% of patients versus 0.9% of patients at weeks 37 to 48 (risk difference [95% CI]: 9.4 [5, 13.7], P=0.0017), respectively.
Thromboembolic events were experienced in 3.6% of luspatercept-aamt-treated patients and hypertension was reported in 10.7% of patients across the clinical development program. The most common adverse reactions were headache, bone pain, arthralgia, fatigue, cough, abdominal pain, diarrhea, and dizziness.

Permanent discontinuation due to an adverse reaction occurred in 5.4% of patients, with the most frequent including arthralgia, back pain, bone pain, and headache.

“Today’s approval is an important milestone and underscores our continued commitment to patients with hematology disorders,” Nadim Ahmed, president of global hematology and oncology for Celgene, said in a statement. “There are very limited options for patients living with anemia due to beta thalassemia who are dependent on long term red blood cell transfusions. We are pleased to make Reblozyl available as a new therapy for these patients to help address their anemia, a significant clinical complication of beta thalassemia.”

Luspatercept-aamt is expected to be available 1 week following the FDA approval, according to Celgene.

Reference

FDA Approves Reblozyl (luspatercept-aamt) for the Treatment of Anemia in Adults With Beta Thalassemia Who Require Regular Red Blood Cell Transfusions [news release]. Celgene. https://ir.celgene.com/press-releases/press-release-details/2019/FDA-Approves-REBLOZYL-luspatercept-aamt-for-the-Treatment-of-Anemia-in-Adults-With-Beta-Thalassemia-Who-Require-Regular-Red-Blood-Cell-Transfusions/default.aspx. Accessed November 8, 2019.