Avanir Pharmaceuticals (AVNR) added $400 million to its valuation on Monday morning with positive results from a phase 2 trial evaluating the safety and efficacy of AVP-923 in Alzheimer’s disease patients with agitation, adding some $500 million to the company’s valuation. Alzheimers is the Bermuda Triangle of drug targets: nothing works, which is why Wall St. is getting on board with AVNR – the stock was up 55% in late morning trading.
AVP-293 is a combination of dextromethorphan hydrobromide, an antitussive in many over-the-counter cough syrups, and quinidine sulfate, an antiarrhythmic agent. Avanir already has the combination approved for pseudobulbar affect as NUEDEXTA at 20mg and 10mg, respectively. The phase 2 study of AVP-923 tested a 30mg/10mg combination.
The trial met its primary endpoint, a significant difference on the agitation/aggression domain score of the neuropsychiatric inventory (NPI) when compared to placebo (p=0.00008). According to the company, improvements were seen in a number of secondary endpoints: NPI total score (p=0.014)l; clinical global impression of change-agitation (p=0.0003); patient global impression of change (p=0.001); and measures of caregiver burden (p≤0.05). The drug was well-tolerated. 10% of patients experienced falls, diarrhea, or urinary tract infections.
In order to reduce placebo response, Avanir used a relatively uncommon Sequential Parallel Comparison Design (SPCD) for the double-blind and controlled 10-week phase 2. Patients were initially randomized 3:4 to receive AVP-923 (dose escalated from 20mg dextromethorphan/10mg quinidine to 30mg/10mg) or placebo. Ha;fway through the study, at the end of week 5, patients who initially received placebo were stratified according to their response to treatment and re-randomized 1:1 to receive either AVP-923 or placebo for the remainder of the study (5 weeks). Patients who initially received AVP-923 continued to receive AVP-923 DM 30mg/ Q 10mg for the remainder of the study.
