Biogen Reports Positive Results for Non-Opioid Oral Pain Drug

On September 16th, Biogen announced that its non-opioid investigational oral pain drug Vixotrigine (BIIB074) demonstrated positive topline results in the Phase 2 CONVEY study in small fiber neuropathy (SFN).

SFN is a kind of peripheral neuropathy characterized by degeneration of small-diameter sensory fibers, including those responsible for pain. It can be spontaneous with no specific reason or triggered by specific illnesses or infections. However, diabetes and impaired glucose tolerance are the most common causes of SFN. Currently, there is no existing medication or therapy to ameliorate or cure the symptoms.

Vixotrigine is a use-dependent voltage-gated sodium channel blocker. As sodium channels play a crucial role in conducting nerve impulses, including in pain-sensitive neurons that respond to tissue damage, Vixotrigine potentially addresses the unmet medical need of individuals suffering from chronic painful neuropathy.

CONVEY Study Results

The efficacy and safety of Vixotrigine were evaluated by a Phase 2, placebo-controlled, randomized withdrawal study CONVEY involving 265 participants with spontaneously caused or diabetes-related SFN. After a four-week open-label run-in period, 123 enrollees who responded to Vixotrigine were randomized to receive either 200 mg or 350 mg of Vixotrigine or placebo twice a day for 12 continuous weeks.

The primary endpoint was to show a statistically significant reduction in the mean average daily pain (ADP) score versus placebo at week 12, while the secondary endpoint was to evaluate the effect on the worst pain, neuropathic pain quality, sleep interference due to pain, patient global impression, use to rescue medication, and SFN symptoms in participants treated with Vixotrigine.

Vixotrigine at 200 mg twice a day showed a statistically significant reduction in the mean ADP and the mean worst daily pain score at week 12; however, the reduction for the spontaneously caused SFN subgroup was not as evident. Less effective than 200 mg twice daily, Vixotrigine administered at 300 mg twice daily did not meet the primary endpoint or some secondary endpoints.

Still, some patients reported feeling “very much improved” or “much improved” when compared to baseline, using the Patient Global Impression of Change (PGIC) questionnaire. Both doses of Vixotrigine were well tolerated and the safety profile aligned with the previous studies.

It is unexpected that the lower dose is, in fact, more effective, and its explanation may be revealed in the upcoming trials. Hopefully, the development team can make some adjustments to Vixotrigine and support SFN patients in the near future.

Author

Judy Ya-Hsuan Lin

Success is the ability to go from one failure to another with no loss of enthusiasm.