Mbx Biosciences provided an update on its obesity portfolio that included preliminary blinded Phase 1 data for MBX 4291, a GLP-1/GIP co-agonist prodrug.
According to the company, data from the first multiple ascending dose Part B cohort (n=8, including two placebo) showed mean weight loss of 7 percent (range 0 to 16 percent) at eight weeks and generally favorable tolerability with one subject experiencing mild diarrhea and no reported nausea or vomiting in the cohort.
Pharmacokinetic findings from single ascending dose cohorts showed a time to maximum concentration of approximately 13 to 14 days, and MAD Part B exhibited an estimated T1/2_Cmax of about 26 days, which the company says supports potential once-monthly dosing.
The 12-week MAD Part C readout is on track for the fourth quarter of 2026. Mbx Biosciences also nominated MBX 5765 as an amycretin prodrug development candidate with IND-enabling studies expected to begin in Q2 2026 and expects to nominate a GLP-1/GIP/glucagon prodrug candidate in Q3 2026.
The company reported proof of concept for once-weekly imapextide in post-bariatric hypoglycemia with reported increases in glucose nadir and decreases in insulin peak across doses. An Obesity Day webcast was hosted on 11 May 2026.
