Pull to refresh
Logo
Daily Brief
Following Why Sign Up
LSD-based pill clears late-stage anxiety trial

LSD-based pill clears late-stage anxiety trial

New Capabilities

Definium's single-dose lysergide tablet cut anxiety scores in its first Phase 3 study, with a second readout due in weeks

August 12th, 2026: Voyage anxiety trial succeeds

Overview

Updated Aug 15

A single dose of LSD, taken as a tablet that dissolves under the tongue, cut anxiety scores for people with generalized anxiety disorder and held that benefit for 12 weeks. On August 12, 2026, Definium Therapeutics said its drug, DT120, beat placebo in its first large late-stage trial. The effect showed up by day two.

No approved anxiety drug works like this. Standard treatments are pills taken daily for weeks. DT120 is one supervised dose in a clinic. If a second trial due in September confirms the result, Definium could file for what would be the first approval of an LSD-based medicine.

Why it matters

Roughly 6% of U.S. adults have generalized anxiety disorder, and many get little help from daily pills. A single dose that works in days would change that.

Questions about this story

Free account needed to ask — your question is kept and asked for you right after sign-up. Answers are public.

No questions yet — be the first to ask.

Key Indicators

5.4 points
Anxiety score gap vs. placebo
Placebo-adjusted drop on the Hamilton Anxiety Rating Scale at week 12 (p<0.0001).
43% vs 16%
Response rate
Share of patients with at least a 50% anxiety reduction, DT120 vs. placebo.
214
Trial participants
Adults aged 18 to 74 randomized across 35 U.S. sites in the Voyage study.
0.81
Effect size (Cohen's d)
A large effect by clinical-trial standards; Jefferies called it among the strongest seen in anxiety.

Voices

Curated perspectives — historical figures and your fellow readers.

Ever wondered what historical figures would say about today's headlines?

Sign up to generate historical perspectives on this story.

Log in Sign Up

People Involved

Robert Barrow
Robert Barrow
Chief Executive Officer, Definium Therapeutics
Leading two Phase 3 anxiety trials and a depression program

Organizations Involved

Definium Therapeutics
Definium Therapeutics
Biotechnology company
Developer of DT120, the LSD-based tablet

A New York-based drug developer, formerly MindMed, betting its future on an LSD tablet for anxiety and depression.
U.S. Food and Drug Administration
U.S. Food and Drug Administration
Federal regulatory agency
Regulator deciding whether LSD becomes an approved medicine

The agency that reviews and approves drugs for the U.S. market.

Timeline

December 2023 August 2026

7 events Latest: August 12th, 2026 · 1 month ago
Tap a bar to jump to that date

  1. Voyage anxiety trial succeeds

    Latest Clinical Trial

    DT120 beat placebo on the Hamilton Anxiety scale by 5.4 points at week 12, with effects from day two. It met every main and secondary goal.

  2. FDA finalizes psychedelic trial rules

    Regulatory

    New guidance spelled out how companies should design psychedelic studies, including how to handle patients guessing which treatment they got.

  3. DT120 wins Phase 3 trial in depression

    Clinical Trial

    The Emerge study showed a single dose cut depression scores sharply within a week and held for weeks. It was the first Phase 3 win for the drug.

  4. MindMed becomes Definium Therapeutics

    Corporate

    The company rebranded and began trading as DFTX. MM120 became DT120. The move signaled a pivot to late-stage psychiatry.

  5. FDA rejects MDMA therapy for PTSD

    Regulatory

    The agency turned down Lykos Therapeutics's MDMA-assisted therapy and asked for another trial. Unblinding worries loomed over the whole field.

  6. FDA grants Breakthrough Therapy designation

    Regulatory

    The FDA flagged the LSD program as promising enough for anxiety to warrant a faster review. Durability data showed the benefit held for 12 weeks.

  7. MindMed's mid-stage anxiety trial hits its mark

    Clinical Trial

    A single dose of MM120 cut anxiety scores far more than placebo at week four, with no required therapy. The result put an LSD drug on a serious path.

Scenarios

1

Second anxiety trial confirms the win

Likely Resolves by End of 2026

Discussed by: Definium Therapeutics guidance; Jefferies analysts

Definium's second pivotal anxiety study, Panorama, reads out in September 2026. It adds a low 50-microgram dose arm to test whether patients were simply guessing they got the real drug. If Panorama hits its main anxiety endpoint with statistical significance, Definium has the two positive Phase 3 trials it needs to build an approval filing.

2

FDA approves the first LSD-based medicine

Possible Resolves by End of 2028

Discussed by: BioPharma Dive; Psychiatric Times

With Breakthrough Therapy status and two positive trials, Definium would submit a New Drug Application for anxiety. The FDA would weigh efficacy against LSD's known risks and the unblinding question that sank the MDMA bid. An approval would be the first ever for a lysergide drug and would set the template for how supervised, single-dose psychedelics reach pharmacies.

3

FDA balks over the unblinding problem

Uncertain Resolves by End of 2028

Discussed by: Science; The Conversation drug researchers

Patients on LSD feel it, so both they and their doctors can often tell who got the drug. That bias helped doom the MDMA application in 2024. The FDA could issue a complete response letter for DT120, asking for more data or another trial, even after positive results. The added 50-microgram arm in Panorama is Definium's attempt to head this off.

4

A larger drugmaker buys Definium

Possible Resolves by End of 2027

Discussed by: BioSpace; industry deal analysts

Two Phase 3 wins in a summer make Definium an obvious target. Big pharmaceutical companies short on new psychiatry drugs could move to acquire it before an approval decision, paying a premium for a first-in-class asset. A deal would fold DT120 into a larger sales and regulatory machine and reshape who controls the launch.

Historical Context

3 moments from history that rhyme with this story — and how they unfolded.

March 2019

Esketamine (Spravato) approval (2019)

The FDA approved Johnson & Johnson's esketamine, a chemical cousin of the party drug ketamine, as a nasal spray for treatment-resistant depression. Patients take it in a certified clinic and stay under watch for two hours because of dissociation and sedation.

Then

It became the first genuinely new mechanism approved for depression in decades, sold under strict in-clinic monitoring rules.

Now

It proved a mind-altering drug could win approval if given under supervision, creating the clinic-based model Definium now follows.

Why this matters now

DT120 uses the same playbook: a powerful psychoactive drug, one supervised dose, monitoring for hours. Esketamine showed regulators can say yes to this format.

August 2024

Lykos MDMA rejection (2024)

The FDA rejected Lykos Therapeutics's MDMA-assisted therapy for post-traumatic stress disorder and asked for another trial. An advisory panel had voted that the trials failed to prove the benefits outweighed the risks. Functional unblinding, patients knowing they got the drug, was a central worry.

Then

The first psychedelic therapy bid collapsed, and three related studies were retracted over conduct problems.

Now

It set a higher bar for the field and made unblinding the question every developer now has to answer.

Why this matters now

It is the cautionary tale Definium is designing around. The extra low-dose arm in Panorama exists to answer the exact objection that sank Lykos.

June 2025

Compass psilocybin Phase 3 (2025)

Compass Pathways reported that its synthetic psilocybin met the main goal of a Phase 3 depression trial. Investors were unconvinced by the size and durability of the effect, and the stock fell by nearly half.

Then

A technical trial success still triggered a sharp sell-off as the market questioned real-world impact.

Now

It showed that meeting an endpoint is not enough; the strength and staying power of the effect decide how a readout lands.

Why this matters now

Definium's larger effect size and day-two onset are exactly the features that Compass was seen to lack, which is why the Voyage numbers drew a different reaction.

Sources

(14)
+8
Business Wire STAT News Psychiatric Times BioSpace BioPharma Dive Fierce Biotech Definium Therapeutics (Investor Relations) JAMA Nature Tech Times ClinicalTrials.gov Business Wire Business Wire Definium Therapeutics (Investor Relations)