Vertex Reports Positive Interim Phase 3 Data for Povetacicept
Vertex Pharmaceuticals says an interim analysis of its Phase 3 RAINIER trial showed its experimental therapy povetacicept significantly reduced proteinuria and improved other disease markers in adults with IgA nephropathy, positioning the drug candidate for a potential U.S. accelerated approval filing this month. At 36 weeks, patients treated with povetacicept achieved a 52% reduction from baseline in proteinuria, measured by the 24-hour urine protein-to-creatinine ratio (UPCR), compared with a 4.3% reduction in the placebo group, the company says. This translated into a placebo-adjusted reduction of 49.8%, a statistically significant result that met the trial’s primary endpoint.
The study also met both secondary endpoints, according to the company. Treatment with povetacicept reduced serum galactose-deficient IgA1 (Gd-IgA1) — a biomarker associated with disease activity — by 77.4% from baseline, compared with a 9.1% increase in the placebo group. The placebo-adjusted reduction was 79.3%.
Among patients who had blood in their urine at baseline, 85.1% of those receiving povetacicept experienced hematuria resolution compared with 23.4% of patients receiving placebo, the company adds.
Povetacicept was generally safe and well tolerated, according to the company. Most adverse events were mild to moderate, and no deaths or drug-related serious adverse events were reported in the trial. Serious adverse events occurred in 3.0% of patients treated with povetacicept compared with 4.3% in the placebo arm.
Vertex says it has already begun submitting portions of a BLA to FDA, and it plans to complete the submission by the end of the month, seeking accelerated approval for the drug. The company intends to use a priority review voucher that could shorten the FDA review timeline from 10 months to six months.
If approved, the therapy would be delivered through a low-volume auto-injector designed for once-monthly at-home administration.