Pharmaprojects R&D Pipeline News Feed
Influenza drug misses crucial primary endpoint in Phase II trial
26 Sep 2007
BioCryst Pharmaceuticals has announced preliminary Phase II findings for its influenza drug peramivir, which has failed to meet the primary endpoint of significant alleviation of influenza symptoms compared to placebo. Peramivir inhibits viral neuraminidases A and B, essential for viral transmission within the host, and is being developed for the treatment of acute seasonal and life-threatening influenza.
This study was designed to test whether high-dose acute intramuscular administration could reduce the duration of seasonal influenza symptoms. Patients were given placebo or single-dose peramivir within 48 hours of symptom onset. The results showed a non-significant trend for improvement in symptoms on peramivir compared to placebo.
Based on a preliminary review, Biocryst believes that the shorter injection needles used in this trial compared to previous trials may have affected the amount of peramivir received. BioCryst in fact estimates that only 1/3 of patients may have had an adequate dose, and a post hoc analysis found that there was a larger effect on the time to alleviation of symptoms in this subset.
The President and CEO of BioCryst, Jon P Stonehouse, responded to these results by stating that "the goal of this Phase II study was to explore the efficacy of peramivir and establish its safety profile. In subjects that we believe received the intended dosing of peramivir, we saw patients achieve symptom relief up to 2.6 days faster than placebo, a result that exceeded our expectations. In addition, peramivir demonstrated a safety profile similar to placebo".
BioCryst is currently conducting a Phase II trial with an intravenous formulation of peramivir in hospitalized acute influenza patients, and intends to progress the intramuscular formulation to Phase III trials, having modified the administration method, to further assess efficacy.
