Vertex Phase II suzetrigine study disappoints

US biopharma Vertex Pharmaceuticals (Nasdaq: VRTX) today announced results from its Phase II study of suzetrigine, an investigational, oral, highly selective NaV1.8 pain signal inhibitor in people with painful lumbosacral radiculopathy (LSR), also known as sciatica.

The study met its primary endpoint with statistically-significant and clinically-meaningful reduction in pain on the numeric pain rating scale (NPRS), but failed to show a significant difference from the placebo, casting doubt on the drug's efficacy. This caused Vertex’ shares to fall more than 10% to $400.99 in pre-market activity.

The study’s primary endpoint was a within-group change from baseline in the weekly average of daily leg pain intensity on the NPRS at Week 12. This 11-point scale ranges from 0 (no pain) to 10 (worst pain imaginable).