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What this page does and does not contain — This page examines the clinical and regulatory landscape for psilocybin-based investigational drugs. It names clinical sponsors and trial programs only to identify their public research records and regulatory milestones. It does not: recommend or endorse any treatment, drug, or program; guide readers toward or away from any investigational therapy; facilitate trial enrollment; provide recruitment or site-location information; reproduce or endorse sponsor investor language as established efficacy; apply full-dose clinical trial findings to microdosing; or link to
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As of mid-2026, no psilocybin-based drug has been approved by the U.S. Food and Drug Administration. The most advanced program — COMP360, a synthetic psilocybin formulation developed by Compass Pathways — has reported positive top-line results from two Phase 3 trials for treatment-resistant depression [1] sponsor-press-release Compass Pathways Successfully Achieves Primary Endpoint in First Phase 3 Trial Evaluating COMP360 Psilocybin for Treatment-Resistant Depression Link → [2] sponsor-press-release Compass Pathways Successfully Achieves Primary Endpoint in Second Phase 3 Trial Evaluating COMP360 Psilocybin for Treatment-Resistant Depression Link → and is pursuing a rolling New Drug Application submission. [3] sponsor-press-release Compass Pathways Announces FDA Granted NDA Rolling Review Request and Awarded Commissioner's National Priority Voucher Link → Usona Institute is conducting a Phase 3 trial in major depressive disorder; results have not yet been publicly announced. [4] trial-registry Psilocybin for Major Depressive Disorder (MDD) (uAspire) Link → The PTSD program remains in early-phase investigation. This page maps the landscape and explains what each status marker means and does not mean.
What the clinical pipeline is
The psilocybin clinical pipeline refers to the set of regulated investigational programs testing pharmaceutical-grade psilocybin or related compounds in formal clinical trials under FDA oversight. These programs operate under Investigational New Drug applications and conduct research in defined patient populations under controlled protocols. They are distinct from state-licensed supervised psilocybin programs in Oregon and Colorado, from research exemptions, from dietary supplements, and from microdosing practices.
Understanding the pipeline requires separating four categories that are often conflated: trial phases, regulatory milestones, press release language, and peer-reviewed publications. Each describes a different type of evidence at a different stage of certainty.
| Category | What it represents | What it does not mean |
|---|---|---|
| Phase 2 results | Safety/tolerability and preliminary efficacy in a smaller controlled study | Established efficacy; FDA approval pathway confirmed |
| Phase 3 top-line data | Sponsor-reported primary endpoint result before full peer review | Peer-reviewed efficacy determination; approval decision |
| Regulatory milestone (BTD, CNPV, NDA rolling review) | An FDA process step that accelerates or structures the review | Approval; rescheduling; lawful public access |
| FDA approval | A formal determination that a specific product is safe and effective for a specific indication | Approval for all psilocybin products, all doses, or all populations |
The programs in the pipeline as of mid-2026
COMP360 (Compass Pathways) — Treatment-Resistant Depression. The most advanced program. Compass Pathways completed two randomized, double-blind, placebo-controlled Phase 3 trials — COMP005 and COMP006 — and both met their primary endpoints. [1] sponsor-press-release Compass Pathways Successfully Achieves Primary Endpoint in First Phase 3 Trial Evaluating COMP360 Psilocybin for Treatment-Resistant Depression Link → [2] sponsor-press-release Compass Pathways Successfully Achieves Primary Endpoint in Second Phase 3 Trial Evaluating COMP360 Psilocybin for Treatment-Resistant Depression Link → The FDA granted a rolling NDA review request and issued a Commissioner’s National Priority Voucher in April 2026. [3] sponsor-press-release Compass Pathways Announces FDA Granted NDA Rolling Review Request and Awarded Commissioner's National Priority Voucher Link → The rolling NDA submission was underway as of mid-2026; the submission was not yet complete and no approval decision had been issued. COMP360 also holds FDA Breakthrough Therapy designation for treatment-resistant depression [5] primary-legal Breakthrough Therapy designation Link → — a development-acceleration status, not an approval.
Usona Institute — Major Depressive Disorder. Usona, a Wisconsin-based nonprofit, received FDA Breakthrough Therapy designation for psilocybin in major depressive disorder in 2019 and launched the uAspire Phase 3 trial (NCT06308653) in 2024. [4] trial-registry Psilocybin for Major Depressive Disorder (MDD) (uAspire) Link → The trial’s primary completion date was January 2026. As of the publish date, Phase 3 top-line results had not been publicly announced.
COMP360 — PTSD. Compass Pathways received FDA acceptance of an IND application for a PTSD program and reported preliminary Phase 2 open-label data from a 22-patient study. A Phase 2b/3 trial was in design. PTSD evidence is substantially less mature than the TRD evidence base.
What “Phase 3” means — and what it does not
Phase 3 is the controlled, late-stage study phase. It uses randomized, double-blind designs with pre-specified primary endpoints in patient populations defined by specific diagnostic criteria. [6] primary-regulatory Psychedelic Drugs: Considerations for Clinical Investigations Link → A Phase 3 result, even a positive one, establishes evidence for that specific indication under those specific trial conditions: a particular dose, a particular administration protocol, a particular comparator, a particular patient definition, and a particular follow-up window.
The Phase 2b COMP001 study established the foundation for the COMP360 TRD program. [7] Clinical trial Single-dose psilocybin for a treatment-resistant episode of major depression doi:10.1056/NEJMoa2206443 Phase 2 findings informed the Phase 3 design but did not themselves constitute the pivotal evidence.
Positive Phase 3 results do not generalize to other indications, other patient populations, other dose levels, or other administration contexts — including unsupervised or microdose settings.
Why these findings do not speak to microdosing
The clinical pipeline addresses supervised full-dose clinical administrations of pharmaceutical-grade psilocybin in structured research settings, with psychological or psychosocial support, to patients with specific diagnoses. Microdosing research examines sub-perceptual repeated doses, typically in general populations without clinical supervision, for a different set of endpoints.
These are different research questions studied under different conditions. The mechanisms may overlap at a pharmacological level, but mechanism does not establish result. The clinical pipeline findings — whether positive or negative — do not establish efficacy for microdosing, and microdosing research results do not extend to supervised clinical-dose findings.
See the Legal Status cluster for the distinction between legal status and safety or efficacy. See the Access cluster for the distinction between availability and legality.
- Treatment-resistant depression (TRD)
- Depression that has not responded to at least two adequate antidepressant treatment courses. The clinical definition matters: TRD trial results apply to this patient population, not to all depression.
- Rolling NDA submission
- A process by which a sponsor submits completed sections of a New Drug Application to the FDA as they are finished, rather than waiting until all sections are complete. It accelerates review but does not guarantee approval.
- Commissioner's National Priority Voucher (CNPV)
- An FDA pilot program designation that can compress the standard review window once a complete NDA is filed. It is an accelerator, not approval.
- Phase 3 primary endpoint
- The pre-specified outcome measure that a Phase 3 trial is powered to detect. Meeting a primary endpoint means the result was statistically significant on that measure under those conditions.