Benzinga | Apr 12, 2021 11:46AM EDT

Sage-Biogen Essential Tremor Candidate Hits Primary Endpoint Goal, But 38% Of People Drop Out

* Sage Therapeutics Inc (NASDAQ: SAGE) and Biogen Inc (NASDAQ: BIIB) have scored their first but narrow win after signing their $3.1 billion deal last year in November.

* SAGE-324, the second major molecule in the pact, cleared a Phase 2 trial for essential tremor (ET), a progressive disorder that causes involuntary muscle movement.

* After 29 days, patients in the SAGE-324 cohort had experienced a 36% reduction in upper limb tremor amplitude, compared to a 21% reduction in the placebo group.

* The difference caused the trial to hit its primary endpoint with a p-value of 0.049. In patients with severe symptoms at baseline, upper limb tremor amplitude fell 41%.

* And the results come with 38% of the patients dropping out from the trial, and most patients reduced their dose because they had difficulty tolerating the drug.

* A statistically significant correlation between upper limb tremor scores and activities of daily living (ADL) results at all time points.

* The trial was not fully powered to examine ADL, a key measure for ET patients, but SAGE-324 numerically beat placebo.

* Safety and tolerability was an issue for some patients, however. The company started patients on 60-mg doses with the option to down-titrate to 45 mg or 30 mg in the event of tolerability issues at the higher dose.

* 62% of participants down-titrated. 38% of patients discontinued dosing altogether.

* Sleepiness or drowsiness was the most common treatment-emergent adverse event, affecting 68% of patients on SAGE-324.

* Price Action: SAGE shares are down 2.77% at $74.49, while BIIB shares dipped 1.28% at $264.74 in the market trading session on the last check Monday.