MBX Biosciences Phase 1 Data Shows 7% Weight Loss, Monthly Dosing Potential
MBX Biosciences reported preliminary Phase 1 MAD Part B data for MBX 4291 showing mean 7% weight loss at week 8 with minimal GI events in an eight-participant cohort, supporting once-monthly dosing potential. It also nominated MBX 5765 as a once-monthly GLP-1/GIP/glucagon/DACRA candidate and cut imapextide Phase 2b funding.
1. Preliminary Phase 1 Data for MBX 4291
Preliminary blinded results from the first MAD Part B cohort (n=8, including 2 placebo) showed mean 7% weight loss (range 0–16%) at eight weeks with only one gastrointestinal event, indicating good tolerability for the dual GLP-1/GIP prodrug.
2. Once-Monthly Dosing Potential
Pharmacokinetic profiling demonstrated gradual accumulation and delayed Tmax supporting a self-titrating weekly induction regimen and potential for true once-monthly administration in the upcoming 12-week MAD Part C trial, with data on track for Q4 2026.
3. Pipeline Prioritization and New Candidate Nomination
MBX Biosciences nominated MBX 5765, a GLP-1/GIP/glucagon/DACRA agonist designed for once-monthly dosing with superior efficacy and tolerability, and reallocated resources by discontinuing further investment in the imapextide Phase 2b trial for post-bariatric hypoglycemia.