Beam Therapeutics: base editing therapy risto-cel meets primary goal in pivotal sickle cell trial
Beam reported that risto-cel, a base-editing therapy for sickle cell disease, met its primary endpoint in a pivotal trial of 31 patients. The company plans an FDA application by year-end.
Beam Therapeutics said on Tuesday that its base-editing treatment ristoglogene autogetemcel (risto-cel) succeeded in a pivotal trial in people with sickle cell disease, according to biopharmadive.com biopharmadive.com
biopharmadive.combiopharmadive.comOpen source ↗. The data came from 31 patients who had completed treatment and 12 months of follow-up as of Oct. 20.
Without releasing specific figures, Beam said risto-cel achieved its primary goal, "freedom from severe VOCs" (vaso-occlusive crises). Secondary objectives, such as a reduction in VOC-related hospital stays, were also met. The company plans to submit an approval application to the US Food and Drug Administration as soon as the end of the year. This is the first positive late-stage readout for base editing.
How base editing works
Base editing is a newer form of gene editing that changes individual nucleotides in a DNA sequence. Unlike older CRISPR approaches, it does not cut through DNA.
Risto-cel and Casgevy, which is made with CRISPR technology, are both produced by extracting and re-engineering a patient's own cells to switch on production of fetal hemoglobin. The modified cells are transplanted back, travel to the bone marrow and begin producing normal blood cells. This is intended to stop the formation of sickle-shaped cells and the painful crises they cause biopharmadive.com
biopharmadive.combiopharmadive.comOpen source ↗.
Market context
If approved, risto-cel would be the third genetic therapy for sickle cell, after Lyfgenia (Genetix Biotherapeutics, formerly Bluebird Bio) and Casgevy (Vertex Pharmaceuticals with CRISPR Therapeutics). It would also compete with hydroxyurea, l-glutamine, blood transfusions and stem cell transplants.
Both approved gene therapies saw slow early uptake. Genetix sold itself after difficulties marketing Lyfgenia and other gene therapies, and only five people received Casgevy in the second half of 2024. Vertex has since reported 64 treated patients in 2025 with $116 million in Casgevy revenue, and $219 million in sales through the first nine months of 2026.
In September, Beam's management told RBC Capital Markets analysts that uptake had been limited by supply constraints rather than slow demand or reimbursement issues. The RBC analysts wrote that risto-cel has a shorter manufacturing process and requires fewer cycles of treatment to mobilize the edited cells biopharmadive.com
biopharmadive.combiopharmadive.comOpen source ↗. CEO John Evans called the data a "defining milestone" for risto-cel and for Beam's base editing technology. Beam's shares fell as much as 10% in Tuesday morning trading.
