Compass Pathways reports second positive Phase 3 trial readout for COMP360 psilocybin in treatment resistant depression

On February 17, Compass Pathways released topline data from its second Phase 3 trial, COMP006. The trial enrolled 581 participants and administered two doses of COMP360 25 mg, 10 mg, or 1 mg, three weeks apart.

At Week 6, the study’s primary endpoint, the 25 mg group showed a statistically significant reduction in MADRS scores compared to 1 mg, with a mean difference of -3.8 points. 39 percent of participants in the 25 mg arm achieved a clinically meaningful reduction in MADRS of at least 25 percent.

Compass also released 26 week data from its earlier COMP005 trial, in which 258 participants received either a single dose of COMP360 25 mg or placebo. 25 percent of participants in the 25 mg arm reached a clinically meaningful reduction in MADRS at Week 6 after a single dose.

The magnitude of the MADRS difference in COMP006 is similar to that reported in COMP005, where a -3.6 point difference versus placebo was observed, and some analysts have described this effect size as modest. Compass has stated that the absolute change from baseline in the 25 mg arm of COMP006 was larger than in COMP005 given the different comparators, placebo in COMP005 and COMP360 1 mg in COMP006, though detailed curves have not yet been released.

The independent Data Safety Monitoring Board reported no new or unexpected safety findings. Most treatment emergent adverse events were mild or moderate and resolved within 24 hours, with headache being the most frequently reported event.

The company has requested a meeting with the FDA and now targets Q4 2026 for completion of its application, suggesting a possible 2027 launch timeline.

Read the full press release here.