We are a clinical-stage biopharmaceutical company developing novel precision peptide therapies to treat endocrine and metabolic diseases. (Incorporated in Delaware)

Our leading drug candidate, MBX 2109, is a parathyroid hormone peptide designed as a potential long-acting hormone replacement therapy for chronic hypoparathyroidism. 

Our company was founded by global leaders with a transformative approach to peptide drug design and development. Leveraging this expertise, we designed our proprietary Precision Endocrine Peptide^™, or PEP^TM, platform to overcome the key limitations of unmodified and modified peptide therapies and to improve clinical outcomes and simplify disease management for patients. Our PEPs are selectively engineered to have optimized pharmaceutical properties, including extended time-action profiles and consistent drug concentrations with low peak-to-trough concentration ratios, consistent exposure to target tissues, and less frequent dosing. We are advancing a pipeline of novel candidates for endocrine and metabolic disorders with clinically validated targets, established endpoints for regulatory approval, significant unmet medical needs and large potential market opportunities.

Our product candidates and programs include:

-MBX 2109: Our lead product candidate, MBX 2109, is a parathyroid hormone peptide prodrug that is designed as a potential long-acting hormone replacement therapy for the treatment of chronic hypoparathyroidism, or HP. Leveraging our proprietary PEP platform, we designed MBX 2109 to treat the underlying pathophysiology of HP by providing a continuous, infusion-like exposure to parathyroid hormone, or PTH, with convenient once-weekly administration. In a Phase 1 clinical trial, MBX 2109 demonstrated a low ratio between the highest concentration of active drug observed after a dose and the concentration of active drug observed immediately prior to the next dose, or peak-to-trough ratio, which is consistent with a continuous, infusion-like profile, and an extended half-life, potentially enabling the first once-weekly PTH dosing regimen for patients with HP. MBX 2109 was generally well-tolerated with no drug-related severe or serious adverse effects. We are currently evaluating MBX 2109 in a Phase 2 clinical trial in patients with HP and dosed our first patient in this trial in August 2024. We anticipate reporting topline data in the third quarter of 2025.

–MBX 1416: We are advancing MBX 1416, which is designed to be a long-acting glucagon-like peptide-1, or GLP-1, receptor antagonist, as a potential therapy for post-bariatric hypoglycemia, or PBH, a chronic complication of bariatric surgery. MBX 1416 is designed as a convenient once-weekly therapy to reduce insulin secretion and increase blood glucose to reduce the frequency and severity of hypoglycemic events. In our ongoing Phase 1 clinical trial, preliminary data regarding the way the compound is absorbed, distributed, metabolized and excreted, or pharmacokinetics, from the single ascending dose portion demonstrated that weekly subcutaneous injections resulted in dose-proportional increases in MBX 1416 exposure and a half-life supporting a once-weekly dosing regimen. We anticipate additional single ascending dose and multiple ascending dose data from our ongoing Phase 1 clinical trial in the fourth quarter of 2024.

–Obesity portfolio: Our lead obesity product candidate, MBX 4291, is designed to be a long-acting and highly potent GLP-1 and glucose-dependent insulinotropic polypeptide, or GIP, receptor co-agonist prodrug with the goal of reducing dosing frequency and improving efficacy and tolerability relative to existing standards of care.

Note: Net loss and revenue are for the 12 months that ended June 30, 2024.

(Note: MBX Biosciences upsized its IPO at pricing to 10.2 million shares – up from 8.5 million shares in the prospectus – and priced the IPO at $16.00 – the top of its $14.00-to-$16.00 range – to raise $163.2 million on Thursday night, Sept. 12, 2024.)

(Note: MBX Biosciences filed an S-1/A on Sept. 9, 2024, and disclosed the terms for its IPO: The company is offering 8.5 million shares at a price range of $14.00 to $16.00 to raise $127.5 million, if priced at the $15.00 mid-point. Background: MBX Biosciences filed its S-1 for its IPO on Aug. 23, 2024, without disclosing the terms. The IPO’s proceeds are estimated at $100.0 million. Background: MBX Biosciences submitted confidential IPO documents to the SEC on March 22, 2024.)