DT120, Definium Therapeutics’ oral LSD formulation, cleared all endpoints in Phase 3 Emerge for major depressive disorder. A single 100-microgram dose posted an 8.1-point placebo-adjusted improvement on the Montgomery-Åsberg Depression Rating Scale at week six. The stock jumped more than 50% when markets opened Monday.
The Emerge study enrolled 149 adults. The effect didn’t stop at week six: DT120 held a 7.3-point placebo-adjusted MADRS reduction at week 12, with no new safety signals detected. Response rates hit 35% for DT120 versus 7% for placebo; remission came in at 24% versus 3%.
CEO Rob Barrow called DT120 a “potential best-in-class treatment for mental health disorders.” The company, formerly MindMed, renamed itself Definium in January and is advancing toward FDA submission. Definium also has an MDMA formulation in autism spectrum disorder in clinical trials. A second Phase 3 study assessing DT120 in generalized anxiety disorder is still running.
Durability is the real differentiator. Spravato, J&J’s approved ketamine nasal spray for MDD, requires supervised clinic visits twice weekly. DT120’s week-12 hold after a single dose points toward far less frequent dosing — that’s an access story, not just a clinical one. Trump’s April 18 executive order also changes the calculus: it directs FDA to issue priority vouchers to psychedelic therapies with Breakthrough Therapy designation, and DT120 holds that status for its GAD program.
Definium hasn’t filed yet. No PDUFA date exists.
Sarah Chen