Compass Delays Pivotal Trial Readouts for Psilocybin in Depression, Lays Off 30% of Staff

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In another delay for the psychedelic treatment space, Compass Pathways announced adjusted timelines for two Phase III trials of its psilocybin to address treatment-resistant depression.

Compass Pathways will delay pivotal Phase III readouts for its psilocybin-based therapy for treatment-resistant depression, resulting in a layoff of around 30% of its workforce, the psychedelic drug developer announced Thursday.

Compass, which revealed the delays in its third quarter business update, had expected data from a first Phase III trial, COMP005, this quarter, according to Fierce Biotech. The company has now shifted that timeline to the second quarter of 2025. Compass had also anticipated data from a second Phase III trial, COMP006, around the middle of 2025, Fierce reported. This readout has now been pushed back to the second half of 2026.

The decision regarding COMP006, a two-dose study, is in response to “the increased regulatory scrutiny on functional unblinding,” according to the company’s press release. In August 2024, the FDA rejected Lykos Therapeutics’ MDMA-assisted post-traumatic stress disorder therapy after an advisory committee voted 10-1 against its approval. Among the top concerns cited by the FDA’s Psychopharmacologic Drugs Advisory Committee was functional unblinding, as they believed participants could tell whether or not they’d been given the drug.

To “protect against the risk of unblinding,” Compass said in its earnings report that it decided to shift the data release for COMP006 until after the 26-week time point when the blinded portion of the trial will be complete for all patients. On an earnings call Thursday, Compass CEO Kabir Nath said “it will be difficult for the overwhelmingly psychedelic-naive participants to determine which dose they received,” according to Fierce.

Nath noted other complexities as contributing to the decision to delay the readouts, including that the use of multiple doses in the Phase III trial “significantly increases the logistical complexity for sites to schedule patients and therapists as well as for patients themselves.”

As a result of the delays, Compass will part ways with approximately 30% of its workforce, including some management positions.

“Ensuring the success of our lead COMP360 program is our absolute priority,” Nath said in a statement. “The shift in the phase 3 pivotal program timeline has forced us to look carefully at our operations and ensure that every resource is focused on this goal.”

Compass had 32 employees at the end of December 2023, 19 of whom were primarily involved in research and development and clinical activities, according to an SEC filing.

COMP360 has shown promise in earlier clinical studies. Results from the company’s Phase IIb trial, published in the New England Journal of Medicine in November 2022, showed “a highly statistically significant reduction in depressive symptoms after three weeks” following treatment with a single dose of COMP360 in combination with psychological support, with the response lasting up to 12 weeks, according to Compass.

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