Another potential Alzheimer’s medication hit a roadblock during the development process. Biotech firm Axovant Sciences reported its experimental treatment targeting Alzheimer’s disease missed its main goals in a late-stage study.

Axovant’s therapy, intepirdine, did not produce improvements in cognition or in measures of activities of daily living for patients with mild to moderate Alzheimer’s disease who were receiving background therapy with another Alzheimer’s drug called donepezil.

Investigators performed a global, randomized, double-blind, placebo-controlled phase III study labeled MINDSET aimed at evaluating the efficacy, safety, and tolerability of intepirdine against placebo on 1,315 patients ages 50 to 85 over the course of 24 weeks.

The goal was to test the effects of the combination therapy based on scores derived from the Alzheimer’s disease Assessment Scale-Cognitive Subscale as well as the Alzheimer’s disease Cooperative Study-Activities of Daily Living Scale.

Overall, the researchers concluded there were no statistically significant changes from the baseline in cognition and essentially no difference between the intepirdine and placebo arms when it came to changes from the baseline in activities of daily living.

"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,” said Axovant CEO Dr. David Hung, M.D., in a statement. “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."

Intepirdine was developed as an oral, once-daily investigational drug to target the 5HT6 receptor, which is a neurotransmitter that is believed to play a crucial role in alertness, memory, thought, and judgement. These are key factors of cognition and function that get impaired in patients with dementia.

The drug when given at higher doses can also block the 5HT2A receptor, which scientists believe plays a critical role in psychosis, REM sleep behavior disorder, and motor function seen in patients with dementia with Lewy Bodies.

Combining intepirdine and donepezil seemed to slow the loss of cognition and ability to perform daily tasks more effectively than donepezil in earlier trials, according to Business Insider.

This data emphasizes how difficult it’s been to launch a new drug for Alzheimer’s as well. There are currently only four approved drugs that treat the symptoms of the disease with the last approval occurring in 2003, and 99 percent of Alzheimer’s drug have failed clinical trials in the past decade.

Another trial is still underway geared towards testing intepirdine efficacy on patients with Lewy Bodies dementia with results expected to be reported by the end of 2017.

"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,” said Hung.