MDMA-Assisted Therapy and What Happens Now That FDA Rejected It

Last reviewed: August 2026 · Psychedelic law changes quickly — verify current status before relying on this page.

Who this is for: Patients considering or researching MDMA-assisted therapy, clinicians trying to understand what is currently available, advocates, and anyone following the policy conversation around psychedelic medicine who wants an accurate account of where things stand.

The short answer

MDMA-assisted therapy for PTSD is not approved. The FDA rejected the application in August 2024, asking for an additional Phase 3 clinical trial before it would reconsider. The company that developed the therapy, now operating under a new name, is continuing negotiations with the FDA. MDMA remains Schedule I federally, with no legal prescription pathway and no state-regulated access program. For patients who wanted this treatment, there is currently no legal route to it in the United States.

The history in brief

MDMA research for PTSD was not new when the FDA rejected it. The nonprofit Multidisciplinary Association for Psychedelic Studies (MAPS) sponsored the first Investigational New Drug application for MDMA with the FDA in 2001. The work that followed — over two decades of Phase 1 and Phase 2 trials — produced enough evidence of efficacy that the FDA granted MAPS Breakthrough Therapy designation in 2017, the first such designation for a psychedelic compound. Breakthrough Therapy status is a research designation that allows the FDA to work more closely with a sponsor to accelerate clinical development. It does not approve a drug.

MAPS created a public benefit corporation — first called MAPS PBC, later renamed Lykos Therapeutics in early 2024 — to carry the development program through Phase 3 and regulatory approval. Two large Phase 3 clinical trials followed: MAPP1 and MAPP2, both randomized, double-blind, and placebo-controlled. Both met their primary endpoint of statistically significant reduction in PTSD symptoms on the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5). Lykos submitted a New Drug Application (NDA) to the FDA in December 2023.

What went wrong at the FDA

On June 4, 2024, the FDA’s Psychopharmacologic Drugs Advisory Committee held a public hearing. The committee voted 2-9 against supporting the effectiveness of MDMA-assisted therapy, and 1-10 to reject the proposition that the benefits of the treatment outweighed its risks with a proposed Risk Evaluation and Mitigation Strategy (REMS). That vote was not binding on the FDA, but the agency followed it. On August 9, 2024, the FDA issued a Complete Response Letter (CRL) to Lykos Therapeutics, declining to approve midomafetamine capsules for PTSD.

The FDA’s specific concerns, made fully public in September 2025 when the FDA released the CRL as part of a broader transparency initiative, included:

Functional unblinding. Because MDMA produces intense and distinctive psychoactive effects, participants in the trials could generally tell whether they had received the active drug or a placebo. This created the possibility that participants’ positive self-reports reflected expectation as much as treatment effect — a problem the FDA called “functional unblinding.” The committee noted this made it difficult to separate MDMA’s pharmacological effect from the psychotherapy component and from participants’ high expectations.

Durability of effect. The FDA stated that Lykos had not demonstrated that the drug’s benefit persisted beyond the 18-week end-of-study assessment, which came eight weeks after the final dosing session. The CRL required evidence of durable efficacy.

Safety reporting and data integrity. The trials lacked systematic documentation of abuse-related adverse events as required by the FDA. The CRL also cited unreported safety events at two different clinical sites. The day after the FDA’s rejection, the journal Psychopharmacology retracted three published papers on MDMA-assisted therapy, citing protocol violations amounting to unethical conduct by researchers at one of the study sites. The journal noted that the authors confirmed they were aware of the violations at the time of submission but did not disclose them.

Prior MDMA use and selection bias. High rates of prior MDMA use among trial participants, combined with high rates of prescreening failures, led the FDA to flag the possibility of selection bias — that the participants who completed the trials were not representative of the broader PTSD population that would use the treatment if approved.

The FDA asked Lykos to conduct a new Phase 3 clinical trial addressing these issues, with psychedelic-naive participants, independent blinded raters, firewalled study teams, and long-term efficacy data extending to one year. The agency also recommended an independent third-party data audit of all study records and reports, while stating it would still consider the existing data in any future resubmission.

MAPS disputed much of the FDA’s reasoning, arguing that the agency had shifted the trial design standards after the key studies were complete — a charge MAPS has characterized as the FDA “moving the goalposts.” MAPS pointed out that the Special Protocol Assessment process in 2017 approved the trial design that the FDA later criticized.

What happened to Lykos

Following the rejection, Lykos cut approximately 75% of its staff. Rick Doblin, the founder of MAPS who had driven the MDMA program for over three decades, left the Lykos board as part of the reorganization. David Hough, a former executive at Johnson & Johnson Innovative Medicine, was appointed to lead clinical development and FDA engagement for any resubmission.

In January 2025, it was reported that Antonio Gracias, a billionaire investor and close associate of Elon Musk, was attempting to acquire control of Lykos with $100 million in new investment, with Doblin’s backing. In March 2025, reporting indicated that reorganization under Gracias was underway.

By September 2025, the company was described as rebranding as Resilient Pharmaceuticals. Lykos and MAPS have both stated their intention to continue pursuing FDA approval of MDMA-assisted therapy. The timeline for any new Phase 3 trial, if initiated, would extend several years before resubmission would be possible.

What this means for patients and clinicians now

There is no legal route to MDMA-assisted therapy in the United States at this time. MDMA remains Schedule I. No state has created a regulated program for MDMA access. No clinical exception, compassionate use pathway, or expanded access program for MDMA therapy is currently operational.

Patients with PTSD interested in MDMA-assisted therapy have three options under current law: enroll in an authorized clinical trial if one is recruiting and they qualify; seek treatment at an international clinic (Mexico, Canada, and other countries have different legal frameworks); or wait for a future approval process to succeed. None of these are immediate or accessible for most people.

Clinicians cannot prescribe or administer MDMA for PTSD. A psychiatrist or therapist who facilitates MDMA sessions — regardless of the therapeutic context — is participating in the distribution or use of a Schedule I controlled substance without authorization, which is a federal crime.

What happens next in the broader field

The FDA’s rejection of MDMA was specific to Lykos’s application and the problems in that development program. It did not close the door on psychedelic-assisted therapy broadly, and other companies have drawn explicit lessons from the Lykos experience in designing their own trials.

As of mid-2025, COMPASS Pathways’ COMP360 psilocybin met its primary endpoint in its first Phase 3 trial for treatment-resistant depression — the first Phase 3 positive readout for any psychedelic compound other than esketamine. A second Phase 3 trial is expected to report results in the first half of 2026, with a potential NDA submission in late 2026 or early 2027.

MindMed received FDA Breakthrough Therapy designation for MM120, a pharmaceutically optimized form of LSD, in March 2024. Phase 3 trials in generalized anxiety disorder were underway as of early 2025.

Cybin’s CYB003, a deuterated psilocybin compound, is in Phase 3 trials for major depressive disorder with topline results expected in 2026.

These programs are proceeding. The MDMA rejection has been absorbed by the field as a data point about trial design and regulatory standards — not as evidence that psychedelic medicine will not reach FDA approval.

Common mistakes and misconceptions

“The FDA said MDMA doesn’t work.” The FDA did not conclude MDMA is ineffective. The rejection was based on concerns about trial design, data integrity, and the inability to adequately blind the studies — not a finding that the underlying therapeutic mechanism fails.

“MDMA is now banned or newly restricted.” MDMA’s Schedule I status did not change. It was Schedule I before the rejection and remains Schedule I. The rejection was an NDA decision, not a scheduling action.

“Patients can access MDMA therapy through compassionate use.” No FDA compassionate use or expanded access program for MDMA-assisted therapy is currently operational. Expanded access requires an application, FDA authorization, and an IND — none of which currently exist for MDMA for PTSD in accessible form.

“Going to a therapist who offers MDMA therapy in a state that has decriminalized it is legal.” No state has created a regulated program for MDMA. City-level decriminalization does not authorize therapeutic administration. A therapist who provides MDMA-assisted sessions is engaged in the distribution of a Schedule I substance.

When you should speak with a lawyer

You should speak with a lawyer if:

You are a clinician who has been administering or facilitating MDMA sessions and want to understand your legal exposure
You are a patient who participated in an unauthorized MDMA therapy session and want to understand what this means legally
You are a healthcare professional building a practice around psychedelic therapy and want to understand what compounds you can and cannot legally work with
You are an investor or founder in a company that has been offering MDMA-adjacent services and need to understand your risk

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This article is public legal education, not legal advice. If your situation is specific, speak with a lawyer who practices in this area.