On Tuesday, Supernus Pharmaceuticals, Inc. (NASDAQ:SUPN) revealed the topline data from the Phase 2b study of SPN-820 in adults with treatment-resistant depression (TRD).

The study did not demonstrate a statistically significant improvement on the primary endpoint of change from baseline in the Montgomery-Åsberg Depression Rating Scale (MADRS) total score to Week 4, a widely used clinician‐rated measure of depressive severity.

Also Read: ADHD Drug Maker Supernus Pharmaceuticals Downgraded On Slower Prescription Growth For Its Top-Selling Drug

There was no treatment difference between SPN-820 and placebo in the change from baseline to Week 4 for the secondary endpoints.

The safety profile of SPN-820 was consistent with previous clinical trials, showing few adverse events.

“We are disappointed that the trial did not meet its primary endpoint in this patient population,” said Jack Khattar, President and CEO of Supernus. “We will continue to analyze these data and discuss the future of the program with our development partner, Navitor Pharmaceuticals.”

In October, Supernus Pharmaceuticals revealed data from its exploratory open-label Phase 2a clinical study of SPN-820 in adults with major depressive disorder.

Phase 2a study demonstrated a rapid and substantial decrease in depressive symptoms. SPN-820 was well-tolerated with few adverse events.

Earlier this month, the FDA approved Supernus Pharmaceuticals’ ONAPGO (apomorphine hydrochloride) injection, formerly known as SPN-830, as the first and only subcutaneous apomorphine infusion device for motor fluctuations in adults with advanced Parkinson’s disease.

Supernus will make ONAPGO available in the second quarter of 2025.

Price Action: SUPN stock is down 14.10% at $34.20 at the last check on Wednesday.

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This article Supernus Pharmaceuticals Stock Falls On Disappointing Data From Treatment-Resistant Depression Trial originally appeared on Benzinga.com

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