Bristol Myers Squibb's Reblozyl Fails to Meet Main Goal in Late-Stage Trial for Myelofibrosis Treatment.

Bristol Myers Squibb announced that its anemia therapy, Reblozyl, developed with Merck, failed to meet the main goal in a Phase 3 trial for certain adults with myelofibrosis, a rare blood cancer. The trial was testing Reblozyl for treating anemia associated with this condition. Bristol Myers Squibb will review the full data and provide further information.

Bristol Myers Squibb (BMY) has announced that its anemia therapy, Reblozyl (luspatercept-aamt), developed in collaboration with Merck, failed to meet the primary endpoint in a Phase 3 trial for treating anemia associated with myelofibrosis, a rare blood cancer [1]. The trial, known as INDEPENDENCE, aimed to evaluate the efficacy and safety of Reblozyl in combination with Janus kinase inhibitor (JAKi) therapy in adult patients with myelofibrosis-associated anemia requiring red blood cell (RBC) transfusions.

The primary endpoint, RBC transfusion independence during any consecutive 12-week period starting within the first 24 weeks of treatment, was not met (p=0.0674). However, the study did show numerical and clinically meaningful improvements in RBC transfusion independence favoring Reblozyl, aligning with previous results from the Phase 2 trial [2]. Several secondary measures also demonstrated a clinically meaningful benefit, including a higher number of patients achieving at least a 50% reduction in RBC transfusion burden and a higher number of patients achieving a hemoglobin (Hb) level increase by at least 1 g/dL while remaining transfusion independent for at least 12 consecutive weeks.

Despite the failure to meet the primary endpoint, the company remains optimistic about the clinically meaningful results and will engage with the FDA and EMA to discuss the submission of marketing applications. "It is promising to see that Reblozyl led to clinically relevant improvement of anemia for patients with myelofibrosis," said Anne Kerber, Senior Vice President, Head of Development, Hematology, Oncology, and Cell Therapy for Bristol Myers Squibb. "We remain confident in the ability of Reblozyl to improve outcomes for patients with myelofibrosis-associated anemia and believe the totality of these results, including meaningful improvements in transfusion burden and hemoglobin levels, support the potential to address an unmet need in patients who have few treatment options."

Myelofibrosis (MF) is a rare type of blood cancer characterized by the buildup of scar tissue in the bone marrow, leading to anemia and other complications. Reblozyl is a first-in-class therapeutic option that promotes late-stage red blood cell maturation. It is currently indicated for the treatment of anemia in adult patients with beta thalassemia who require regular RBC transfusions and in certain adult patients with myelodysplastic syndromes (MDS) who may require RBC transfusions [3].

The trial results underscore the need for further research and development in the treatment of myelofibrosis-associated anemia. The company's next steps will involve reviewing the full data and providing further information. Investors and financial professionals should closely monitor the company's progress and any potential regulatory decisions.

References:
[1] Bristol Myers Squibb. (2025). Bristol Myers Squibb Announces Topline Results from Phase 3 INDEPENDENCE Trial for Reblozyl® (luspatercept-aamt) in Adult Patients with Myelofibrosis-Associated Anemia. Retrieved from https://news.bms.com/news/details/2025/Bristol-Myers-Squibb-Announces-Topline-Results-from-Phase-3-INDEPENDENCE-Trial-for-Reblozyl-luspatercept-aamt-in-Adult-Patients-with-Myelofibrosis-Associated-Anemia/default.aspx
[2] ClinicalTrials.gov. (2021). NCT03194542: Phase 2 Trial of Reblozyl in Patients with Myelodysplastic Syndromes. Retrieved from https://clinicaltrials.gov/ct2/show/NCT03194542
[3] Bristol Myers Squibb. (2021). Reblozyl (luspatercept-aamt). Retrieved from https://www.bms.com/products/reblobyl