MBX Biosciences shares one-year data for weekly hypoparathyroidism candidate
MBX Biosciences (NASDAQ:MBX) announced detailed results from its 12-week Avail Phase 2 clinical trial and new one-year data from an ongoing open-label extension study evaluating its investigational endocrine therapy, canvuparatide.
The updates, presented at the ENDO 2026 annual meeting, indicate that the once-weekly parathyroid hormone (PTH) peptide prodrug provided sustained metabolic regulation and reduced supplement dependence in adults with chronic hypoparathyroidism.
In the double-blind, placebo-controlled Phase 2 portion of the trial, canvuparatide achieved a 63% responder rate at 12 weeks, compared to 31% for the placebo cohort.
The primary composite endpoint required participants to maintain normal, albumin-adjusted serum calcium levels while eliminating active vitamin D and reducing daily oral calcium supplements to 600 milligrams or less.
Longitudinal tracking from the open-label extension demonstrated durable efficacy, with a 57% responder rate recorded at the one-year milestone alongside a 90% patient retention rate.
Secondary clinical metrics over the 52-week interval indicated broader systemic stabilization.
Treatment with canvuparatide led to sustained blood calcium control, decreased urinary calcium excretion, and improvements in kidney function, as measured by an increased estimated glomerular filtration rate (eGFR).
Bone biopsy and biomarker evaluations also revealed physiologic bone remodeling patterns, contrasting with the accelerated bone turnover or adynamic bone states often associated with alternative therapeutic approaches.
The safety assessment over the one-year exposure window revealed a well-tolerated profile, with the majority of reported adverse events classified as mild or moderate in severity and no treatment-related serious adverse events documented.
Backed by the completed dataset and a prior End-of-Phase 2 regulatory alignment with the FDA, management confirmed that the company remains on track to initiate a pivotal Phase 3 confirmatory trial of canvuparatide in the third quarter of 2026.
