Q4 2025 Recap: Hematology News and Updates

After a relatively quiet year, the last quarter of 2025 brought a landslide of major updates to the hematology sphere. Between key approvals from the US Food and Drug Administration (FDA), such as mitapivat and narsoplimab, and the results of major trials like SUMMIT and VAYHIT3, the specialty has grown substantially during the last 3 months.

The editorial team at HCPLive has collected 9 of the most impactful hematology headlines from Q4 of 2025 – check them out below:

FDA News

FDA Approves Mitapivat for Transfusion-Dependent and Non-Transfusion-Dependent Alpha- and Beta-Thalassemia

Mitapivat, a small-molecule oral PKR activator developed by Agios, received approval from the FDA on December 24, 2025, for the treatment of anemia in adults with transfusion-dependent or transfusion-independent alpha- or beta-thalassemia. The decision was based on positive results from the phase 3 ENERGIZE and ENERGIZE-T trials, during which more patients treated with mitapivat achieved a transfusion reduction response and had a hemoglobin response compared to those receiving placebo.

FDA Approves Narsoplimab (Yartemlea) As First TA-TMA Therapy

Narsoplimab-wuug was approved for hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA) on December 24, 2025, as announced by parent company Omeros Corporation. This decision makes narsoplimab the first and only approved lectin pathway inhibitor approved by the FDA. The decision was based on positive data from a single-arm, open-label study in adults with TA-TMA, which was supported by data from an expanded access program enrolling 221 adult and pediatric patients.

FDA Approves Fibrinogen, Human-chmt (Fesilty) for Congenital Fibrinogen Deficiency

Fibrinogen, human-chmt was approved on December 19, 2025, for the treatment of acute bleeding episodes in pediatric and adult patients with congenital fibrinogen deficiency (CFD), including hypo- or afibrinogenemia. The FDA’s decision comes in response to a phase I/III study, during which the only adverse events that occurred in >2% of patients receiving fibrinogen, human-chmt were pain in extremity, back pain, pyrexia, thrombosis, fibrin D dimer increase, headache, hypersensitivity reactions, and vomiting.

FDA Approves Etuvetidigene Autotemcel (Waskyra) For Wiskott-Aldrich Syndrome

Etuvetidigene autotemcel became the first FDA-approved gene therapy for Wiskott-Aldrich syndrome on December 9, 2025. The drug uses the patient’s hematopoietic stem cells, which have been genetically modified to include functional copies of the WAS gene. These cells are then infused intravenously to restore blood cell production, as well as functional WAS protein expression in affected cells.

FDA Approves Omidubicel-onlv (Omisirge) As First Cellular Severe Aplastic Anemia Therapy

On December 8, 2025, the FDA approved omidubicel-onlv to treat severe aplastic anemia (SAA), establishing it as the first hematopoietic stem cell transplant therapy for this disease. Omidubicel-onlv involves donated cord blood stem cells chemically enhanced with nicotinamide and given to a patient to restore their blood and immune system. This circumvents issues such as delayed hematopoietic recovery and increased infections presented by umbilical cord blood cells, as well as providing additional graft options for patients with SAA.

Trial Updates

BASIS: Marstacimab Confirms Efficacy and Safety for Hemophilia A and B

The BASIS trial was an open-label, 1-way crossover, multicenter phase 3 trial investigating marstacimab for a primary efficacy endpoint of annualized bleeding rates versus previous therapy during a prior phase 1b/2 study. Patients ultimately saw a mean bleeding rate reduction from 39.86 to 3.2, while those receiving routine prophylaxis saw a reduction from 7.9 to 5.09.

SUMMIT: Bezuclastinib Outperforms Placebo in Nonadvanced Systemic Mastocytosis

During the phase 2 SUMMIT trial, patients were randomly assigned in a 2:1 ratio to receive bezuclastinib or placebo, on top of supportive care medication. Patients assigned to bezuclastinib displayed substantially greater symptom improvement compared to placebo, with a reduction in serum tryptase of ≥50% achieved by 87.4% of bezuclastinib patients versus 0% on placebo. Parent company Cogent Biosciences also announced plans to present data from a 48-week follow-up period at an upcoming scientific meeting in the first quarter of 2026.

Ianalumab Improves Stable Response, Reduces Fatigue in ITP, With Hanny Al-Samkari, MD

Presented at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition by Hanny Al-Samkari, MD, the Peggy S. Blitz Endowed Chair in hematology and oncology at the Massachusetts General Hospital and associate professor of medicine at Harvard Medical School, the VAYHIT2 trial demonstrated ianalumab’s efficacy in prolonging time to treatment failure, improving stable response at 6 months, reducing fatigue, delaying need for subsequent therapy, and facilitating tapering off eltrombopag in patients with primary immune thrombocytopenia.

HOPE-B: 5-Year Etranacogene Dezaparvovec Maintains Durable Efficacy and Safety in Hemophilia B, With Steven Pipe, MD

The HOPE-B trial, presented at ASH 2025 by Steven Pipe, MD, a professor of pediatrics and pathology at the University of Michigan, showed that a single dose of etranacogene dezaparvovec maintains durable and endogenous factor IX Padua expression, producing sustained reductions in bleeding rates among patients with severe or moderately severe hemophilia B. During the trial, patients receiving etranacogene dezaparvovec exhibited a substantial reduction in bleed rates for all bleeds during the first 60 months post-therapy.