Compass tracks PTSD improvements as psilocybin therapy sails to midphase data drop

Compass Pathways has navigated to another successful midphase readout, linking its psilocybin therapy and psychological support to improvements in post-traumatic stress disorder (PTSD) in a small study.

London-based Compass is primarily focused on treatment-resistant depression, an indication in which it expects to have phase 3 data this year, but is also exploring the potential of its COMP360 psilocybin treatment in other settings including PTSD. Compass’ review of the literature suggests about 20% to 30% of patients reach full remission on current therapies.

To test whether COMP360, a formulation of the active ingredient in magic mushrooms, can improve outcomes, Compass enrolled 22 people with PTSD in an open-label phase 2 trial. Participants received a single dose of COMP360 and psychological support from a licensed medical professional.

At baseline, participants scored an average of 47.5 on the CAPS-5 symptom scale, indicating they had severe PTSD. Compass tracked a mean 29.9-point reduction after four weeks. The reduction was almost identical, 29.5 points, after 12 weeks. More than half of participants had a score of 20 or less, meaning they were in remission, at Week 12. Two adverse events of suicidal ideation resolved during the study.

Sertraline and paroxetine, selective serotonin reuptake inhibitors sold respectively as Zoloft and Paxil, received approval in PTSD more than 20 years ago. Lykos Therapeutics, formerly MAPS Public Benefit Corporation, has filed for approval of its MDMA-assisted therapy for PTSD earlier this year.

Lykos is seeking approval on the strength of a pair of phase 3 clinical trials that linked the therapy to 24.4 and 23.7 point reductions in CAPS-5 from baseline after 18 weeks. The Lykos studies were far larger than the Compass trial and had placebo control arms, complicating comparisons between the studies. With those caveats, Compass’ data look competitive, and the company is exploring “the optimal path forward.”

Compass contends its therapy has other advantages over MDMA, the active ingredient in the street drug also known as ecstasy or molly. Talking at a Needham investor event in April, Compass CEO Kabir Nath said “it's important to stress that [MDMA is] a very different model and modality from what we are offering,” notably because it “really requires intensive therapy” rather than just psychological support. 

Teri Loxam, chief financial officer at Compass, used the event to discuss the next steps in PTSD, explaining that the company would potentially like to do a broader, later-stage trial in the indication but hadn’t included the costs in its cash runway. Loxam said Compass, which ended March with almost $263 million, would “need to raise additional funds or change something” to finance further work in PTSD.