New 6-Month Data From Second Phase 3 Trial Confirms Rapid Effect of COMP360 for TRD

Compass Pathways announced today the Part B 26-week results from its second ongoing phase 3 COMP006 trial of COMP360—a synthetic, proprietary formulation of psilocybin—for treatment-resistant depression (TRD).¹ These 26-week results confirm COMP360’s rapid onset and durable profile in nearly 600 patients and build on previously reported results from the first phase 3 trial, COMP005,² which demonstrated rapid onset and durable response to at least 6 months, with a generally well-tolerated and safe profile in individuals living with TRD.

Results

In COMP006, participants had current depressive episodes lasting on average longer than 3 years and an average of more than 6 lifetime depressive episodes. In this severe population, investigators found that 39% of participants in the 25 mg arm achieved a clinically meaningful reduction in MADRS (≥ 25%) by week 6, following 2 fixed doses of COMP360, and maintained durable response at least through week 26. This compares favorably to the 25% in the first study, COMP005, following just a single dose. Ultimately, these findings support the value of a second dose in enhancing clinical benefit for some patients.

NDA Submission

A rolling New Drug Application (NDA) submission and initial review with the US Food and Drug Administration (FDA) is currently underway. Final submission is on track for completion in Q4 of 2026.

“The COMP006 data further strengthens our robust clinical package for COMP360 and represents an important step toward completing our NDA submission,” said Kabir Nath, the chief executive officer of Compass Pathways. “COMP360 has demonstrated consistent results, with rapid onset and durable benefit for people living with chronic, treatment-resistant depression. We are convinced this profile will lead to a profound shift in mental health care—moving beyond daily or frequent administration towards an option potentially involving just a few treatments in a year that could be life changing for patients.”

Combined Data

Alongside results of COMP005, the COMP006 26-week data confirm a consistent, differentiated profile for COMP360, with rapid onset and durable benefit observed across 2 large, well-controlled phase 3 studies in TRD. COMP006 Part A successfully met its primary endpoint at week 6, showing that COMP360 had a rapid onset of effect, with consistent separation between the 25 mg and the 1 mg arm maintained through the randomized, blinded Part B period to week 26. Retreatment in Part B further enhanced benefit: nearly 30% of participants who achieved a clinically meaningful response at week 6 later went into remission following retreatment in Part B.

“We are grateful to the hundreds of participants across our phase 3 program along with the sites, providers, and caregivers who have made it possible for us to generate data supporting the safety and efficacy of COMP360. The participants in our phase 3 program reflect the clinical reality of TRD: people with a chronic, treatment-resistant condition who had already been failed by multiple antidepressant regimens and, in many cases, were in their current depressive episode for nearly four years,” said Guy Goodwin, MD, the chief medical officer of Compass Pathways. “COMP360 has demonstrated rapid, durable and reproducible clinical effects through at least 6 months—with a consistent safety profile—across 2 large, well-controlled phase 3 studies in TRD. Against a high level of chronicity and treatment resistance, this achievement at scale is remarkable in one of psychiatry’s most underserved patient populations. For a condition that places profound burden on patients, families, and the health care system, COMP360 has the potential to establish a new standard of care and fundamentally change what patients and clinicians can expect from treatment.”

Safety and Tolerability

As to safety and tolerability, COMP360 continues to demonstrate a generally well-tolerated and safe profile, with the vast majority of treatment-emergent adverse events (TEAEs) being transient and predominantly occurring on day of dosing. The most common adverse events were nausea, headache, anxiety, and visual hallucination. Serious adverse events were similar across arms (6.3% in the 1 mg arm and 5.7% in the 25 mg arm) over 26 weeks, but low overall across the trial.

“The latest results from Compass’ COMP006 Part B mark an important step towards bringing a novel class of therapeutics to the many patients in need,” said Tobias Marton, MD, PhD, the chief medical officer of Mindful Health Solutions. “The patients enrolled in Compass’ trial had a high degree of treatment resistance reflected by a current episode length of more than 3 years on average and a history of over 6 lifetime episodes. With 39% of patients achieving a clinically meaningful response after 2 doses of psilocybin—an effect maintained for an average of 6 months—and almost 30% of those responders going into remission in the treatment interval, these results are exciting. For us, this represents a significant advancement for psychiatry that will strengthen our ability to reduce the suffering and improve the lives of some of our sickest patients.”

Future Directions

Compass anticipates the launch of COMP360 in the first half of 2027 subject to FDA approval and following Drug Enforcement Administration rescheduling.

“As we advance launch preparations for TRD, we continue to have active interactions with the FDA with our rolling NDA submission underway and on track for final submission in Q4, and launch anticipated in the first half of 2027. We are excited by the data we have generated for COMP360 and thrilled for the millions of patients with TRD who could potentially benefit from our achievements,” concluded Nath.

References

1. Compass Pathways announces six-month data from second phase 3 trial confirming rapid and durable profile. News release. July 7, 2026. Accessed July 7, 2026. https://ir.compasspathways.com/News--Events-/news/news-details/2026/Compass-Pathways-Announces-Six-Month-Data-from-Second-Phase-3-Trial-Confirming-Rapid-and-Durable-Profile/default.aspx

2. Compass Pathways successfully achieves primary endpoint in first phase 3 trial evaluating COMP360 psilocybin for treatment-resistant depression. News release. June 23, 2025. Accessed July 7, 2026. https://ir.compasspathways.com/News--Events-/news/news-details/2025/Compass-Pathways-Successfully-Achieves-Primary-Endpoint-in-First-Phase-3-Trial-Evaluating-COMP360-Psilocybin-for-Treatment-Resistant-Depression/default.aspx