Definium's LSD-Derived DT120 ODT Delivers Third Straight Phase 3 Clinical Win in Generalized Anxiety Disorder

Definium's LSD-Derived DT120 ODT Delivers Third Straight Phase 3 Clinical Win in Generalized Anxiety Disorder

On September 14, 2026, Definium Therapeutics announced positive topline results from its Phase 3 Panorama study evaluating its proprietary, pharmaceutically optimized formulation of lysergide (LSD), known as DT120 ODT (Orally Disintegrating Tablet), in adults with generalized anxiety disorder (GAD). This marks Definium's third successful late-stage trial for DT120 in just 12 weeks, following a Phase 3 win in major depressive disorder (MDD) in June and the Phase 3 Voyage GAD trial in August.

The positive readout establishes Definium's leading position in the psychedelic drug development landscape and sets the stage for a New Drug Application (NDA) filing in 2027.

Efficacy Data and Functional Unblinding Mitigation

The Panorama trial enrolled 245 patients randomized to receive a single dose of 100 µg DT120 ODT, a 50 µg low-dose control arm, or a matching placebo. The 50 µg arm was specifically designed to still induce mild psychoactive effects without therapeutic benefit to address the critical issue of "functional unblinding" in psychedelic trials:

"The Panorama trial did compare Definium’s DT120 ODT to placebo, the study also pitted the 100 μg dose against a 50 μg dose, which is meant to still be psychoactive but not produce any therapeutic benefit.¹"

The trial demonstrated robust, statistically significant efficacy for the therapeutic dose:

• 100 µg Efficacy: Reduced Hamilton Anxiety Rating Scale (HAM-A) scores by 9.8 points at week 12 compared to 4.7 points for the placebo group, representing a highly significant 5.1-point placebo-adjusted difference.
• 50 µg Dose Separation: The 50 µg control arm scored a 3.6-point placebo-adjusted reduction, which was clearly surpassed by the 100 µg dose.

Definium CEO Robert Barrow emphasized that the separation between the therapeutic and low doses successfully validates the drug's true pharmacological effect:

"We don't have any question that there's a robust and real drug effect that we're seeing at 100 μg that isn't present to the same magnitude or durability at a lower dose."

Clinical Delivery and Next Steps

DT120 ODT utilizes Catalent's Zydis ODT fast-dissolve technology to improve bioavailability and reduce gastrointestinal side effects. In clinical settings, the treatment is administered in a single, eight-hour session under the supervision of a trained chaperone. Scott Aaronson, M.D., chief science officer at Sheppard Pratt’s Institute for Advanced Diagnostics and Therapeutics and a trial investigator, highlighted the profound clinical significance of a single-dose treatment for chronic anxiety:

"What stands out about DT120 ODT is that a single dose has the potential to hold a response for months without the patient managing a pill every day."

Definium has scheduled a meeting with the FDA for the fourth quarter of 2026 to map out its regulatory filing strategy. The company also plans to present four-year durability data from its Phase I/II study by the end of Q3 2026, launch a pivotal trial in PTSD in 2027, and continue its ongoing Phase 3 depression trials.