Supernus Pharmaceuticals may have had a potential path forward for its depression drug candidate cut off after the asset missed its primary endpoint in a phase 2b trial. SPN-820 failed to improve the symptoms of patients with treatment-resistant depression (TRD) after four weeks, the company announced Feb. 18.
“We are disappointed that the trial did not meet its primary endpoint in this patient population,” Jack Khattar, president and CEO of Supernus, said in a release. “We will continue to analyze these data and discuss the future of the program with our development partner, Navitor Pharmaceuticals.”
The phase 2b randomized, placebo-controlled study enrolled around 250 adult patients, Supernus said in the release. Patients received either two or four 400-mg doses orally every day.
Patients given SPN-820, however, showed no improvement in their Montgomery-Åsberg Depression Rating Scale scores, a measure of symptom severity, compared to patients given placebo, according to the release.
The safety profile was similar to prior trials, Supernus said, with few adverse events.
In October, Supernus debuted data from a small trial in 40 patients with major depressive disorder (MDD), showing that SPN-820 improved their symptoms at a level the biotech called “clinically meaningful.” At the time, Supernus said it would decide which indication to pursue further—MDD, TRD or both—after the phase 2b data in TRD were available.
Maryland-based Supernus first licensed the mTORC1 activator SPN-820, also known as NV-5138, from Navitor Pharmaceuticals in 2020 for a $10 million fee and a $15 million investment. Total payments from the deal could top $400 million if certain milestones are hit, according to a filing with the Securities and Exchange Commission.
Shares in Supernus dropped by 20% in afterhours trading Tuesday night on the news.