The designation was supported by the significant unmet medical need in MDD and results from the Company's Phase 3 Emerge study, in which a single 100 µg dose of DT120 ODT demonstrated a statistically significant 8.1-point placebo-adjusted improvement in Montgomery-Åsberg Depression Rating Scale (MADRS) total score at Week 6 (p<0.0001), with durable efficacy through Week 12.

This milestone marks the second Breakthrough Therapy designation from the FDA for the DT120 development program, following its initial designation for the potential treatment of GAD. The FDA’s Breakthrough Therapy designation is a process designed to expedite the development and review of innovative medicines intended to treat serious conditions where preliminary clinical evidence indicates that the therapy may demonstrate substantial improvement over available therapy on one or more clinically significant endpoints.

"Securing our second Breakthrough Therapy designation, closely following the unprecedented results from our Phase 3 Emerge study, underscores the potential of DT120 to meaningfully transform the treatment landscape for people living with serious mental health disorders," said Rob Barrow, Chief Executive Officer of Definium Therapeutics. "This recognition of DT120’s promise, first in GAD and now in MDD, reinforces the urgency to advance and deliver rapid, durable benefit across multiple indications. Our focus remains on developing innovative therapies that have the potential to expand treatment options and improve outcomes for the millions of people who continue to seek meaningful relief."

MDD is characterized by at least five depressive symptoms, lasting two weeks or longer, which may include feelings of worthlessness, fatigue, impaired social functioning, and recurrent thoughts of death.1 With more than 21 million U.S. adults experiencing a major depressive episode each year, MDD is the second-most common mental health disorder in the U.S. and a leading cause of disability worldwide.2,3,4 Despite the availability of first-line treatments, fewer than one-third of patients reach remission, underscoring the critical unmet need for more effective treatment options.5