Biogen has announced positive top-line data from the Phase II CONVEY clinical trial of its non-opioid oral pain drug candidate, vixotrigine (BIIB074), to treat small fiber neuropathy (SFN).
A peripherally and centrally acting agent, vixotrigine blocks voltage-dependent and use-dependent voltage-gated sodium channels, which are vital for the conduction of nerve impulses.
The placebo-controlled, double-blind, randomised withdrawal Phase II trial assessed the drug candidate’s efficacy and safety to treat pain in 265 patients with idiopathic or diabetes mellitus-related SFN.
A four-week open-label run-in period was followed by randomisation of 123 responders to vixotrigine to be given either 200mg or 350mg dose of the drug or placebo twice-daily for 12 weeks in the double-blind part.
Data showed that 200mg twice-daily dose of vixotrigine led to a statistically significant decrease in the mean average daily pain (ADP) score compared to placebo at week 12, meeting the primary endpoint.
A subgroup analysis found treatment effect in subjects with diabetes mellitus but not in the smaller subgroup of those with idiopathic SFN.
The 200mg dose also offered statistically significant improvement as against placebo on the mean worst daily pain score at week 12, Biogen said.
In addition, the dose had a numeric benefit over placebo on other secondary endpoints, such as the proportion of subjects with a two-point or greater improvement in the ADP score and those with ≥30% decrease in ADP at week 12, but did not achieve statistical significance.
The 350mg twice daily dose did not attain the primary endpoint of mean change in ADP at week 12.
But 350mg vixotrigine led to a statistically significant rise in the proportion of subjects who were ‘very much improved’ or ‘much improved’ compared to baseline.
Both drug doses were generally well tolerated and the safety profile was similar to that observed in prior studies, without any evidence of abuse potential.
Biogen senior vice-president and therapeutics development head Katherine Dawson said: “We are encouraged by the overall results of the CONVEY study, especially given the significant unmet medical need for additional agents to treat chronic painful neuropathy.”
Earlier this year, Biogen and its partner Eisai unveiled the design of a real-world observational Phase IV study, named ICARE AD-US, of Aduhelm (aducanumab-avwa) in Alzheimer’s disease.