Developing Novel drugs with Clinical Differentiation
Rezubio is a clinical-stage biotechnology company founded by scientists with decades of combined experience in small molecule and peptide drug discovery and development. Our leadership team brings deep expertise across medicinal chemistry, disease biology and pharmacology, CMC, and clinical development, with track records from global pharmaceutical organizations including Merck Sharp & Dohme, Novartis, and Roche.
Rezubio leverages its proprietary MADD platform to create gut-specific therapeutics against targets with proof-of-concept—such as GPCRs, transporters, and ion channels. By restricting drug action to the gut and minimizing systemic exposure, our platform can revive some targets that previously failed in clinical trials because of adverse effect caused by drugs in the systemic exposure. This approach opens new opportunities to develop safer, more effective medicines for metabolic, cardiometabolic, immune and inflammatory diseases.
GPR40 complex structure with full agonist AP8 (PDB: 5TZY)
Improved safety window
The kinetophore anchors the MADD molecule to the outer leaflet of the cell-membrane lipid bilayer in a specific orientation, and the molecule does not penetrate the membrane. MADD molecule consistently shows extremely low oral bioavailability (0.1–0.3%) and minimal systemic exposure—reducing risks of adverse effects.
Enhanced intrinsic potency
The membrane-anchoring feature enriches the molecule at the site of the target protein, resulting in higher local concentration and greater potency compared with the pharmacophore alone.
Optimized PK profile
The kinetophore stabilizes the molecule by keeping it non-penetrant, preventing intracellular enzymes from accessing and metabolizing it. As a result, our MADD molecules consistently show very low oral bioavailability, low clearance, and high gut distribution across multiple preclinical species.
Sustained effect for long-lasting efficacy
The MADD molecules have high affinity to cell membrane and long residence time in target tissue, allowing once-daily or even less frequent dosing.