Beam Therapeutics announced new data from its BEACON Phase 1/2 clinical trial of BEAM-101 in patients with sickle cell disease (SCD) with severe vaso-occlusive crises (VOCs). The data, presented at the 66th American Society of Hematology (ASH) Annual Meeting, highlight the potential of BEAM-101 to deliver meaningful clinical benefits to patients with severe SCD.
Consistent with previously announced data, updated results from seven patients treated with BEAM-101 demonstrated robust and durable increases in fetal hemoglobin (HbF) and reductions in sickle hemoglobin (HbS), rapid neutrophil and platelet engraftment, and normalized or improved markers of hemolysis. Notably, no VOCs were reported post-engraftment.
Matthew M. Heeney, M.D., associate chief of hematology at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center, stated, “These initial data from the BEACON trial are very encouraging and highlight the potential of BEAM-101 to deliver meaningful clinical benefits to patients with severe sickle cell disease. The data from the first seven patients demonstrate the ability for BEAM-101 to dramatically modify the hemoglobin profile to express a majority of protective fetal hemoglobin. All patients mobilized efficiently and had rapid engraftment with a low number of neutropenic days. I look forward to the continued maturation of the data to provide further insights into the long-term benefits of BEAM-101 for people living with sickle cell disease.”
Key Efficacy and Safety Findings
As of the Oct. 28, 2024, data cut-off, seven patients with severe SCD were treated with BEAM-101, with follow-up ranging from 1 to 11 months. Key highlights from the analysis include:
- Rapid and Sustained Increases in Protective Fetal Hemoglobin (HbF): All patients achieved endogenous HbF levels exceeding 60% and a reduction in sickle hemoglobin (HbS) below 40% that was durable. A pancellular distribution of HbF was observed after the elimination of transfused blood.
- Robust and Sustained Total Hemoglobin (Hb) Levels: Total hemoglobin levels increased rapidly, with resolution of anemia in patients after the elimination of transfused blood.
- Efficient Cell Collection and Rapid Engraftment: All patients achieved the minimum target cell dose in either 1 or 2 cycles of mobilization (average: 1.4). The mean time to neutrophil engraftment was 17.1 days (range: 15–21), with a low mean duration of neutropenia (6.3 days). The mean time to platelet engraftment was 19.1 days (range: 11–34).
- Normalization of Hemolysis Markers: Key markers of hemolysis, including indirect bilirubin, haptoglobin, lactate dehydrogenase, and reticulocytes, normalized or improved in all patients following BEAM-101 treatment.
- Safety Profile: The safety profile of BEAM-101 was consistent with busulfan conditioning and autologous hematopoietic stem cell transplantation (HSCT). The most common treatment-emergent adverse events (TEAEs) were consistent with busulfan conditioning, including febrile neutropenia, stomatitis, and anemia. One patient died four months after BEAM-101 infusion due to respiratory failure that was determined by the investigator to be likely related to busulfan conditioning and deemed unrelated to BEAM-101. No VOCs were reported post-engraftment.
BEAM-101 and ESCAPE Programs
John Evans, chief executive officer of Beam, emphasized the potential of Beam’s base-editing technology, stating, “We believe these early data for BEAM-101 are a testament to the potential of our base-editing technology to provide a differentiated option for sickle cell patients, having demonstrated a robust increase in fetal hemoglobin of >60%, a decrease in hemoglobin S to <40% and resolution of anemia in all patients. Additionally, the data from our ESCAPE nongenotoxic conditioning program – to be presented on Sunday – highlight our commitment to expanding access to treatment by decreasing the burden and complications patients potentially face when undergoing transplantation. We look forward to continuing to rapidly advance both programs for patients with sickle cell disease.”
About BEAM-101
BEAM-101 is an investigational genetically modified cell therapy for the treatment of severe sickle cell disease (SCD). The one-time therapy consists of autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) that have been base-edited in the promotor regions of the HBG1/2 genes and are administered via a hematopoietic stem cell transplant procedure. The BEAM-101 edit is designed to inhibit the transcriptional repressor BCL11A from binding to the promoter without disrupting BCL11A expression, leading to increased production of non-sickling and anti-sickling fetal hemoglobin (HbF) and thus mimicking the effects of naturally occurring variants seen in hereditary persistence of fetal hemoglobin. The safety and efficacy of BEAM-101 are being evaluated in the ongoing BEACON Phase 1/2 study, an open-label, single-arm, multicenter trial in adult patients with SCD with severe vaso-occlusive crises (VOCs).
