Xenoport, Inc. (XNPT) Monday reported negative results from a Phase 2b clinical trial of arbaclofen placarbil, also known as AP, as adjunctive therapy in patients with gastroesophageal reflux disease or GERD who do not experience complete relief of GERD symptoms while being treated with proton pump inhibitors or PPI.
XenoPort is currently developing AP as a potential treatment for patients with spasticity. AP is a patented new chemical entity that is a Transported Prodrug of R-baclofen designed to engage natural nutrient transport mechanisms found on intestinal cell membranes, thereby gaining efficient entrance into the bloodstream.
The primary efficacy endpoint was percent change from baseline in heartburn events per week with the primary analysis evaluating percent change from baseline in heartburn events at week six. Percent change in weekly heartburn events was analyzed using a repeated measures ANCOVA model.
At week six, subjects in the placebo group showed a mean percent reduction in heartburn events of 68%. Although there were trends for improvement over placebo in the AP dose groups, none of the comparisons to placebo reached statistical significance, noted Xenoport.
In the pre-market hours, XNPT shares are currently down by 9.30%, trading at $6.05.
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