Relmada Therapeutics has dosed the first patient in the Phase III Relight (study 304) trial evaluating oral antidepressant REL-1017 as an adjunctive major depressive disorder (MDD) treatment.

The placebo-controlled, double-blind, randomised study intends to enrol nearly 300 patients who did not respond to ongoing antidepressant therapies.

It will assess the safety and efficacy of REL-1017, a NMDA receptor (NMDAR) channel blocker targeting hyperactive channels while maintaining physiological glutamatergic neurotransmission.

Change in the Montgomery-Asberg Depression Rating Scale (MADRS) total score from baseline to day 28 for REL-1017 compared to placebo is the primary endpoint.

Relmada chief medical officer Cedric O'Gorman said: “The dosing of the first patient in this important study represents a significant milestone in the ongoing late-stage development programme of REL-1017 for the adjunctive treatment of MDD.

“Relight has been designed to better control placebo response by reducing the time spent by patients at sites and to prioritise the quality of subject enrolment and overall data.

“We are confident that the optimised study protocol will enhance the potential for success in the Relight trial.”

Relight trial is a part of Relmada’s Phase III development programme which also includes the ongoing Reliance II (study 302) trial. Enrolment in this study is anticipated to be completed in the first half of next year.

In addition, results from the long-term, open-label Reliance-OLS (study 310) of REL-1017 are expected in the current quarter.