Beam Therapeutics’ Base Editing Gene Therapy Resolves Anemia in SCD Patients

CAMBRIDGE, Mass., Dec. 06, 2025 (GLOBE NEWSWIRE) –Beam Therapeutics Inc. today announced highly encouraging, updated safety and efficacy data from its BEACON Phase 1/2 clinical trial of ristoglogene autogetemcel (risto-cel, formerly BEAM-101), an investigational genetically modified ex vivo base editing cell therapy for severe sickle cell disease (SCD). The results, presented at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition, demonstrate durable disease correction and resolution of anemia.

Data from 31 adult and adolescent SCD patients treated with risto-cel showed robust clinical benefits:

• High and Durable HbF: Patients achieved a mean Hemoglobin F (HbF) induction of over 60%, which was maintained for up to 20 months of follow-up.
• HbS Reduction: Pathologic Hemoglobin S (HbS) levels were consistently reduced to below 40%.
• Anemia Resolution: All treated patients experienced resolution of anemia after the elimination of transfused blood.

John Evans, chief executive officer of Beam Therapeutics, highlighted the efficiency of the base editing approach: “The strength of these updated data from the BEACON trial reinforce the potential of risto-cel to deliver durable clinical benefit through efficient, more precise editing… We’re on track to efficiently dose the remaining patients enrolled in the study and advance toward a regulatory filing.”

Efficient Treatment Process and Favorable Engraftment

The updated data, which included a cut-off date of August 6, 2025 (with follow-up ranging from 0.3 to 20.4 months), detailed a streamlined treatment process. Patients required a median of only one cell collection cycle, and bone marrow reconstitution was rapid:

• Neutrophil Engraftment: Median time was 17.5 days.
• Platelet Engraftment: Median time was 19 days.

Furthermore, no patient experienced any investigator-reported severe vaso-occlusive crises (VOCs) post-engraftment.

Safety Consistent with Transplant Protocol

The safety profile of risto-cel was reported as consistent with busulfan conditioning, autologous hematopoietic stem cell transplantation (HSCT), and the underlying SCD. The most common adverse events were expected outcomes of busulfan conditioning, such as stomatitis and febrile neutropenia. The company also reported that one patient died four months post-infusion due to respiratory failure deemed likely related to the busulfan conditioning.

The base editing mechanism in risto-cel is designed to inhibit the transcriptional repressor BCL11A from binding, leading to increased production of non-sickling fetal hemoglobin (HbF) and mimicking the protective effects of naturally occurring variants seen in hereditary persistence of fetal hemoglobin.