AVANIR Pharmaceuticals, Inc. (NASDAQ: AVNR) today announced detailed results from the confirmatory double-blind Phase III STAR trial evaluating two doses of the investigational drug Zenvia™ (dextromethorphan/quinidine) compared to placebo in the treatment of pseudobulbar affect (PBA) in patients with underlying multiple sclerosis (MS) or amyotrophic lateral sclerosis (ALS). Over the course of the 12-week study, Zenvia 30/10 mg and 20/10 mg met the primary efficacy endpoint by reducing PBA episode rates by an incremental 47.2% and 47.8% respectively, beyond placebo (p<0.0001). These results were presented today during a late-breaker poster session at the 134th Annual Meeting of the American Neurological Association in Baltimore, MD (Poster Number: WIP-24).
EFFICACY HIGHLIGHTS
- Both the Zenvia 30/10 mg and 20/10 mg groups met the primary efficacy endpoint by demonstrating a significant reduction in daily PBA episode rates relative to the placebo group
- The proportion of patients with complete remission of PBA episodes was significantly greater in both Zenvia treatment groups versus placebo
- The percent of days that were episode-free was significantly higher in the Zenvia groups versus placebo
- Zenvia 30/10 mg demonstrated statistical superiority in time to onset of clinically meaningful effect
- Both Zenvia groups demonstrated a greater proportion of patients versus placebo that achieved response thresholds of 50%, 75% and 90% improvement
- Mean reduction from baseline in CNS-LS score was significantly greater for both Zenvia treatment groups than in the placebo group
- Zenvia 30/10 mg demonstrated significantly greater mean improvement in SF-36 Mental Health Summary scores compared to placebo
- Zenvia 30/10 mg demonstrated significantly greater mean improvement in Beck Depression Inventory scores compared to placebo
In an additional analysis of the primary endpoint pre-specified in the protocol, the percentage of patients that achieved and maintained complete episode remission during the last 14 days of the study was 76% in the Zenvia 30/10 mg group, 80% in the 20/10 mg group and 61% in the placebo group>
p<0.0001 for overall treatment effect throughout the entire study. aITT = intent-to-treat population, refers to all patients randomized.
A 30% decrease from baseline in number of PBA episodes was considered to indicate the onset of a clinically meaningful effect. At day 15, the earliest time point assessed, 72% of patients in the Zenvia 30/10 mg group had experienced an onset of meaningful effect compared to 59% in the placebo group (p<0.0358). The difference between the Zenvia 20/10 mg and placebo groups showed a trend for a higher proportion in the 20/10 mg group.
“Frequent, unrelenting and unpredictable emotional outbursts may occur in progressive neurological conditions, such as ALS, MS, and dementia, or strokes and traumatic brain injuries. The results of the STAR trial indicate that the new low dose formulations of Zenvia can dramatically reduce the debilitating episodes of PBA and may one day help improve the lives of these patients,” said Benjamin Rix Brooks, MD, Director of Carolinas Neuromuscular/ALS-MDA Center and Steering Committee Member for the STAR trial.
“We were thrilled with the Zenvia clinical profile that emerged in the STAR trial,” said Randall Kaye, MD, AVANIR’s Chief Medical Officer. “The data demonstrated a profound treatment effect across multiple efficacy measures in PBA combined with an improved safety and tolerability profile relative to the previous formulation. With the STAR trial data in hand, our team is now working to expeditiously assemble and submit our full response to the FDA approvable letter with the objective of securing approval in the second half of 2010.”