Definium Therapeutics stock climbed 26% on Monday after the company revealed positive topline data from its Phase 3 Emerge trial testing DT120 Orally Disintegrating Tablet (ODT) in major depressive disorder (MDD).
The randomized study met its primary endpoint and achieved all prespecified key secondary efficacy endpoints. For the primary measure - change from baseline on the Montgomery-Åsberg Depression Rating Scale (MADRS) at Week 6 - DT120 ODT demonstrated an 8.1-point placebo-adjusted improvement, with a p-value reported as less than 0.0001. For a secondary efficacy milestone at Week 12, the treatment produced a 7.3-point MADRS placebo-adjusted change from baseline, also with a p-value of less than 0.0001.
Emerge enrolled 149 adults aged 18 to 74 across 20 clinical sites, including participants with a DSM-5-confirmed diagnosis of MDD. Patients randomized to DT120 ODT 100 micrograms registered a Least Squares mean change from baseline in MADRS total score of -13.3 at Week 6, compared with a -5.2 mean change among those receiving placebo.
The trial’s safety assessments showed DT120 ODT was generally well tolerated. The company reported that 99% of treatment-emergent adverse events were mild to moderate in severity. There were no serious adverse events reported, and no suicidality signal was observed. Discontinuation rates were described as low and comparable between the active and placebo groups.
Operational measures from dosing sessions were also provided: on the day of dosing, 100% of participants met the end-of-session checklist criteria by hour 8, and the average time to meet those criteria was 5.8 hours.
Additional efficacy outcomes included a 35% response rate and a 24% remission rate at Week 6 among patients treated with DT120 ODT. By comparison, placebo-treated patients had a 7% response rate and a 3% remission rate at the same time point.
The Emerge trial is one of two pivotal Phase 3 studies Definium is conducting in MDD. The company noted a second pivotal study, named Ascend, is underway; Ascend includes a low-dose arm and is structured in two parts. In that study participants are randomized in a 2:1:2 ratio to receive DT120 ODT 100 micrograms, DT120 ODT 50 micrograms, or placebo.
Context and market reaction
The announcement of statistically robust placebo-adjusted MADRS improvements at Weeks 6 and 12 was followed by a notable move in the company’s shares. The response in equity markets followed the topline release rather than any additional operational or financial disclosures.
Methodology notes
All efficacy and safety outcomes described above were reported by the company as top-line results from the Emerge Phase 3 study. The sample size for the trial was 149 participants across 20 sites, and the active dose in the reported cohort was 100 micrograms of DT120 ODT.