REC-994 is being developed by Recursion Pharmaceuticals specifically for treating symptomatic cerebral cavernous malformations.
The Phase I trial of REC-994, using healthy volunteers, was completed in late 2020. The Phase II Sycamore trial testing the safety and tolerability of the medicine in patients with CCM enrolled its first patient in March 2022. It completed the enrollment of 60 patients ahead of schedule in June 2023. Patients were randomized into three groups: a high-dose group (400 mg/day), a low-dose group (200 mg/day), and a placebo group. This was a double-blinded trial, meaning neither the participants nor the study staff knew which group had been assigned.
Phase 2A sycamore trial Results
In February, 2025, Recursion presented detailed results of the Sycamore Trial at the International Stroke Conference. From the news coverage:
According to the results of the 62-person Phase II study, 50% of patients with cerebral lesions on the highest dose of REC-994 (400 mg) showed reduction in total lesion volume compared to 28% of patients on the placebo after 12 months of treatment. Patients on the lower dose of REC-994 (200 mg) had similar changes in lesion volume compared to placebo. Similar trends were seen in patients with brainstem lesions, a population with high unmet need as cavernomas located in the brainstem are not amenable to surgical intervention.
Additionally, the modified Rankin Scale, which is widely recognized and approved by the U.S. Food and Drug Administration (FDA) to assess functional outcomes in acute stroke trials, indicated positive trends in patients on the 400 mg arm.
This is promising data that allows Recursion to move the REC-994 program forward. Many of the patients in the trial continue to be enrolled in the study as part of a long term extension study.
what happens now
The next steps will be guided by discussions with the FDA and the data from the ongoing long-term extension study. We can expect more information later in 2025.
More background
Chris Gibson, Recursion CEO, presents the results of the REC-994 Phase 2 Sycamore Trial during a March 2025 webinar.
Chris Gibson gave the keynote speech at our July 2023 Scientific Meeting and Family Conference. In this presentation, he offers detailed information about the history of REC-994 development and Recursion’s work.
Join one of our patients as he begins participating in the clinical trial.
READ MORE
In this blog post, Recursion’s CEO Chris Gibson shares the origin story of REC-994 beginning in graduate school at the University of Utah.
Updated 03.12.2025
