06:01 PM EDT, 10/17/2024 (MT Newswires) -- Supernus Pharmaceuticals ( SUPN ) said late Thursday the phase 2a open-label study of SPN-820 in adults with major depressive disorder yielded "promising" data.

The company said the study evaluated the safety and tolerability of a 2400 mg dose of the investigational drug given once every three days as an adjunctive treatment to the current baseline antidepressant therapy.

The company said the data showed "clinically meaningful improvement" based on scores from Hamilton and Montgomery Asberg depression rating scales and an 80% drop in "suicidal ideation."

SPN-820, a first-in-class intracellular modulator of the mechanistic target of rapamycin complex 1 for depression treatment, was also found to be "well-tolerated with few adverse events and had acceptable tolerability with a discontinuation rate of 2.5% due to [adverse events]," it said.

Supernus said enrollment in the phase 2b randomized double-blind placebo-controlled study of SPN-820 in adults with treatment-resistant depression is set to be completed in November, with topline results expected in the first half of 2025.