MBX Biosciences Canvuparatide Hits 63% Responder Rate in Phase 2 Avail, Sustains Through One-Year Open-Label Extension, Phase 3 Set for Q3 2026
MBX Biosciences (Nasdaq: MBX) on June 12 reported full 12-week Phase 2 Avail data and one-year open-label extension results for once-weekly canvuparatide, a precision PTH peptide for chronic hypoparathyroidism. The trial hit its primary endpoint with a 63% responder rate versus 31% on placebo at 12 weeks; the OLE delivered a 79% responder rate at six months and 57% at one year. Patients showed normalized serum calcium, reduced urine calcium excretion, restored bone metabolism, and improved eGFR; 90% of OLE patients remained on study at one year with no new safety signals. A registrational Phase 3 in chronic hypoparathyroidism starts Q3 2026.