Supernus Pharmaceuticals’ Stock Plummets as Phase 2b Depression Drug Trial Fails to Meet Primary Endpoint

Supernus Pharmaceuticals' stock dropped over 20% in premarket trading on Wednesday, February 19, 20256.

The company's Phase 2b study of SPN-820 in adults with treatment-resistant depression (TRD) failed to meet its primary endpoint10.

The study did not show a statistically significant improvement in the Montgomery-Åsberg Depression Rating Scale (MADRS) total score compared to placebo at Week 410.

SPN-820 is a novel, first-in-class intracellular modulator of mTORC1 being developed for depression treatment2.

This outcome contrasts with promising results from an earlier Phase 2a open-label study of SPN-820 in adults with major depressive disorder, which showed rapid and substantial decreases in depressive symptoms25.

The safety profile of SPN-820 remained consistent with previous clinical trials, showing few adverse events10.

Supernus Pharmaceuticals' CEO, Jack Khattar, expressed disappointment with the trial results and stated that the company will continue to analyze the data and discuss the future of the program with their development partner, Navitor Pharmaceuticals10.

This setback comes shortly after a positive development for Supernus, as the FDA recently approved their Parkinson's disease treatment ONAPGO (apomorphine hydrochloride) injection10.

Sources:

2. https://ir.supernus.com/news-releases/news-release-details/supernus-announces-promising-data-open-label-phase-2a-study-spn

5. https://www.fiercebiotech.com/biotech/supernus-links-depression-drug-fast-responses-small-trial

6. https://uk.marketscreener.com/quote/stock/SUPERNUS-PHARMACEUTICALS--10523839/news/Supernus-Pharma-Sinks-Premarket-After-Treatment-Resistant-Depression-Study-Misses-Primary-Endpoint-49098340/

10. https://in.benzinga.com/general/biotech/25/02/43815436/supernus-pharmaceuticals-stock-falls-on-disappointing-data-from-treatment-resistant-depression-trial