US-based Biota Pharmaceuticals has reported top-line data from a Phase II clinical trial comparing the safety and efficacy of a 40mg and 80mg dose of laninamivir octanoate (LANI) with placebo.
639 patients across 12 countries in the northern and southern hemispheres were enrolled in the randomised, double-blind, placebo-controlled, parallel-arm Phase II trial, referred to as IGLOO.
Of the 639 patients, 248 had PCR-confirmed influenza A or B virus and were included in the intent-to-treat efficacy analyses.
Approximately 75% and 19% of the influenza-confirmed patients were infected with influenza A H1N1 2009 and H3N2, respectively, while 6% were infected with influenza B.
Measured by the Flu-iiQ patient-recorded outcome questionnaire, neither the 40mg or 80mg group achieved significant reduction of median time to alleviation of symptoms compared to the placebo, which was the primary endpoint of the trial.
The median time to alleviation of influenza symptoms was 102.3 hours for the 40mg group and 103.2 hours for the 80mg group, as compared with 104.1 hours for the placebo group.
Patients in both the 40mg and 80mg group showed a statistically significant reduction in viral shedding on day three of the trial compared to the placebo, as quantified by qRT-PCR.
In addition, a statistically significant proportion of patients in both the 40mg and 80mg groups were culture negative on day three of the trial as compared with placebo.
The company said that influenza-infected patients in the 40mg group also showed a statistically significant reduction in the incidence of secondary bacterial infections as compared with placebo.
Biota Pharmaceuticals president and CEO Russell Plumb said: "It is disappointing that the rapid and significant onset of antiviral activity against the influenza virus that the two treatment arms demonstrated with LANI did not translate into a meaningful reduction in the time to alleviate patient-reported influenza symptoms.
"We expect to complete a full analysis of additional clinical, safety and pharmacokinetic data forthcoming from this trial over the next several months; however, at this time we do not have any plans to independently advance the development of LANI for the treatment of influenza and intend to evaluate next steps for the LANI programme outside of Japan with our partner, Daiichi Sankyo."
Biota intends to provide a detailed update on the full efficacy and safety results of the Phase II IGLOO trial, the status of the LANI programme and its corporate strategy during its fourth quarter and fiscal year-end earnings call in early September.
LANI is a second-generation octanoyl ester prodrug of laninamivir that has showed in vitro neuraminidase-inhibitory activity against influenza A and B viruses, including subtypes N1 to N9, swine origin H1N1 strains and oseltamivir-resistant viruses.