Definium Therapeutics said its LSD-based treatment DT120 significantly improved major depression symptoms in its first Phase 3 trial. Six weeks after a single dose, the company reported a 13.3-point reduction on the MADRS depression scale versus a 5.2-point reduction with placebo. The effect partially waned by 12 weeks but remained largely maintained, with an 11.0-point reduction from baseline compared with 3.6 points in the placebo group. Definium’s update pushes DT120 closer to a potential regulatory pathway, depending on full trial disclosure and subsequent studies. The company positioned its results as exceeding analyst expectations, framing the data as a step toward broader validation of psychedelic-assisted approaches in psychiatry clinical development.