Psychedelic Treatment of Generalized Anxiety Disorder (GAD)

2026 is an exciting year for those who have been following the research into using psychedelics for the treatment of psychiatric disorders. I recently added a full page on psychedelics here which gives a broad overview of three drugs that are most likely to be brought into clinical practice in the coming years: LSD, psilocybin, and MDMA.

As progress unfolds, I hope to add shorter, more in-depth blog posts on these topics.

In that vein, for this post I want to focus on Definium Therapeutics’ proprietary LSD formulation, known as DT120 ODT (orally disintegrating tablet). This company has many research arms moving forward at once, with two of the most promising ones being for the treatment of Major Depressive Disorder (MDD) and Generalized Anxiety Disorder (GAD).

In mid-August 2026, Definium announced positive topline results for its Voyage trial, which is a randomized, double-blind, placebo-controlled study looking at the efficacy of DT120 ODT for GAD. The standardized dose was 100µg.

The announcement can be read in full here.

Some highlights that I take away from this as an outpatient psychiatrist:

• Direct medication effect

  • This study has never utilized a psychotherapy protocol, so what we are seeing is direct medication effect. While their protocol includes an observer who may offer guidance or support as needed throughout the treatment, there is no required psychotherapeutic intervention.

  • In terms of scalability into clinical practice, this is great news.

• Rapid onset

  • The positive effects were rapid, often seen as early as Day 2, with sustained effect throughout the study, which was up through Week 12.

  • Compare this to the standard 4-8 weeks that standard SSRIs take to achieve similar results. Many patients stop the medication too soon for this reason.

• Dose finding rigor in Phase 3

  • Definium is pursuing a second Phase 3 study, which they call Panorama, that will not only look at 100µg vs. placebo, but will also include a third dosing arm at 50µg.

  • I like this because the company is not only banking on replicating their data, but they are also planning to show that the separation from placebo is real, and that there is indeed a dosage threshold that needs to be met.

• Favorable safety profile

  • Any adverse effects were mild and transient.

  • A worry that I and many other psychiatrists have had about these compounds is that they may precipitate mania or psychosis. At least in these controlled trials where the highest-risk patients were excluded, that has not proven to be the case.

The last medication FDA-approved for GAD was Cymbalta (duloxetine) way back in 2004. As it has been over two decades since this condition has received any new pharmaceutical treatments, the results of this Voyage trial are welcome news.

Let’s wait and see what their Panorama trial shows next.

Conflicts of interest and financial disclosures at time of publication: None.