On February 8, 2023, the US Food and Drug Administration (FDA) informed Blueprint Medicines Corporation that the Phase 1/2 VELA trial of BLU-222 had been placed on partial clinical hold due to the presence of visual adverse events (AEs) in a small number of patients. According to the study, the drug is being administered to the patients who are currently enrolled in the trial.
Currently, the Phase 1 dose escalation portion of the VELA trial is evaluating BLU-222. To date, patients have been treated with BLU-222 at doses ranging from 50 mg BID to 800 mg BID, with no discontinuations due to adverse events and evidence of clinical benefit.
The transient, reversible episodes of light sensitivity and blurred vision that were reported as visual AEs. Except for one Grade 3 event involving light sensitivity and blurred vision in a patient treated with 600 mg BID, all events were Grade 1. With dose interruption or reduction, all events subsided. Patients who have undergone thorough ophthalmologic examinations have not presented with any abnormal findings that are indicative of treatment, such as uveitis.
According to Becker Hewes, Chief Medical Officer at Blueprint Medicines, the company prioritizes patient safety and is collaborating closely with the FDA to investigate the reported visual events and change the VELA trial protocol to provide special guidance to investigators to monitor and manage the adverse events when they do occur.
Based on the activity and safety data they have uncovered thus far in the dose escalation study, Becker Hewes added that they are confident in BLU-222’s benefit-risk profile. They also aim to resume enrollment as quickly and responsibly as possible, recognizing the urgency of treating patients with CDK2-vulnerable cancers, many of whom have seen their disease progress after exhausting all other options.