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Complete Response Letter (CRL)

Regulatory

The FDA's formal rejection letter for a drug application, explaining what would need to change for approval.

Example: Lykos (now Resilient Pharmaceuticals) received one for its MDMA-PTSD therapy in August 2024, and has since quietly resubmitted without running a new Phase 3 trial — see where that stands.

What is a Complete Response Letter?

The FDA's formal rejection letter for a drug application, explaining what would need to change for approval.

Has any psychedelic therapy received a CRL?

Yes — Lykos (now Resilient Pharmaceuticals) received one for its MDMA-PTSD therapy in August 2024, and has since quietly resubmitted without running a new Phase 3 trial. See where that stands and the Rysanso entry.

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Psychedelics in Uniform: What the Military Did to Soldiers, and What the VA Is Now Asking of Veterans

The Army spent decades dosing enlisted men with psychedelics they weren't told they were taking. Eighty years later, the VA and Pentagon are running versions of the same experiment again — with consent forms, IRBs, and an executive order behind them.

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