Compass Pathways plc (NASDAQ:CMPS) on Wednesday shared topline 52-week Part C results from its Phase 3 COMP005 study evaluating COMP360, a proprietary synthetic formulation of psilocybin, for treatment-resistant depression.
Following the announcement, the stock jumped over 11%.
The updated data reinforces the therapy’s differentiated clinical profile, showcasing durable, long-lasting mental health benefits for trial participants.
Long-Term Efficacy And Trial Structure
The trial enrolled 258 participants. In Part A, participants received either a 25 mg dose or placebo through Week 6, while Part B evaluated a second dose of the initial assignment through Week 26.
Approximately 70% of participants continued into the open-label Part C stage spanning Weeks 26 to 52.
Among participants initially randomized to the 25 mg arm, approximately 80% received an open-label dose during Part C, representing their second or third total dose.
This group achieved an average 13-point MADRS score reduction from baseline at Week 52, demonstrating that supplemental dosing can deepen responses and extend efficacy out to one year.
Rapid Onset and Safety Results
Additionally, roughly 90% of placebo participants entered Part C and received their first 25 mg COMP360 dose.
This cohort registered an average 10-point MADRS score drop from baseline by the end of Part C, affirming rapid onset and durability from a single administration.
Across all Part C participants receiving a 25 mg dose, researchers recorded 40% to 45% response rates and approximately 30% remission rates across all time points in the six weeks following dosing.
Safety findings in Part C remained consistent with earlier trial phases, showing a generally well-tolerated profile with no new safety signals.
FDA Filing Underway
Compass said its rolling New Drug Application submission and review are underway. The company expects to complete the filing in the fourth quarter.
Subject to Food and Drug Administration approval, Compass continues to target a commercial launch in the first half of 2027.
COMP360 is a proprietary synthetic formulation of psilocybin and has FDA Breakthrough Therapy designation for treatment-resistant depression.
Compass Pathways Price Action
CMPS Stock Price Activity: Compass Pathways shares were up 11.32% at $15.63 at the time of publication on Wednesday, according to Benzinga Pro data.
Image via Shutterstock
