Axovant Sciences announced that the Phase 3 MINDSET clinical trial of its investigational drug intepirdine in patients with mild to moderate Alzheimer’s disease (AD) who were receiving background donepezil therapy did not meet its co-primary efficacy endpoints. At 24 weeks, patients treated with 35 mg of intepirdine did not experience improvement in cognition or in measures of activities of daily living as measured by the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) and by the Alzheimer’s Disease Cooperative Study-Activities of Daily Living scale (ADCS-ADL), respectively, compared to patients treated with placebo. In the study, intepirdine was generally well tolerated.

After 24 weeks of treatment, change from baseline in cognition was non-significantly improved in the intepirdine arm versus the placebo arm (0.36 ADAS-Cog points; p-value = 0.22). In addition, there was essentially no difference between the intepirdine and placebo arms in change from baseline in activities of daily living (0.09 ADCS-ADL points; p-value = 0.83). Of the endpoints analyzed to date, the only endpoint in which any significant improvement was seen in the intepirdine arm versus the placebo arm was in the first key secondary endpoint, the Clinician Interview-Based Impression of Change plus caregiver interview, or CIBIC+ (0.12 CIBIC+ points; p-value = 0.02). The company will work with investigators to conclude the MINDSET open-label extension study.

“While we are deeply disappointed by these trial results, we also are saddened for the millions of patients and families impacted by Alzheimer’s disease. However, we believe that the fight against Alzheimer’s and other important areas of unmet need in neurology is too important to be derailed by this setback,” says David Hung, MD, CEO of Axovant. “We are grateful to the investigators, patients and caregivers who participated in this important trial and supported us in this journey. Moreover, we remain committed to advancing our pipeline, which includes our Phase 2b HEADWAY study of intepirdine, and nelotanserin, our highly selective inverse agonist of the 5-HT2A receptor in Phase 2 development, both of which are being evaluated in patients with dementia with Lewy bodies.”

The HEADWAY trial studying intepirdine in patients with dementia with Lewy bodies (DLB) remains on track to report topline results at the end of 2017. This study investigates two doses of intepirdine, 35 mg (the dose used in the MINDSET trial) and 70 mg, a higher dose intended to engage both 5-HT6 and 5-HT2A receptors. Intepirdine has received Fast Track designation from the U.S. Food and Drug Administration for the treatment of DLB.