Polymyxin/Colistin

In response to the clinical treatment dilemma of multidrug-resistant Gram-negative bacterial infections, polymyxin, as a classic representative of polypeptide antibiotics, exerts its bactericidal effect by acting on the phospholipid structure of the bacterial cell membrane, increasing the permeability of the cell membrane, and promoting the leakage of important intracellular substances. It is currently the last-line defense drug for refractory infections caused by carbapenem-resistant Enterobacteriaceae (CRE), Pseudomonas aeruginosa and so on. It is mainly indicated for patients with severe infections such as hospital-acquired pneumonia, complicated urinary tract infection, and septicemia that do not respond to other drug treatments, and has irreplaceable clinical value in the treatment system for drug-resistant bacterial infections.

At present, the global polymyxin market size maintains a steady growth trend. In 2023, the overall market size was approximately RMB 1.28 billion, with a compound annual growth rate of around 6%. Driven by the rising global bacterial resistance rate and expanding clinical drug demand, the market has sufficient growth momentum. In the competitive landscape, generic drugs dominate, and domestic enterprises are the main suppliers of polymyxin API in the world. The domestic market has completed multiple rounds of provincial centralized procurement, the winning bid prices have stabilized, and clinical accessibility has been significantly improved.

Polymyxin was originally developed by the Pharmacological Institute of the University of Copenhagen in Denmark, and was subsequently commercialized by multiple pharmaceutical companies. The mainstream original research brand name is "Colimycin", and its core compound patent has expired worldwide. At present, commonly used clinical dosage forms include polymyxin B sulfate for injection and colistin sulfate for injection, with a conventional specification of 500,000 units per vial. Both preparations have been included in the *Catalogue of Chemical Reference Preparations* of China, and are also listed in the FDA Reference Preparation Catalogue. In China, polymyxin APIs from more than 15 enterprises have obtained A status after CDE registration, and polymyxin for injection preparations from more than 10 enterprises have been approved for marketing. (Data as of July 2025, please refer to the official CDE website for the latest information)

CATO can provide a full set of impurity reference standards for polymyxin. Most products are available from stock, and in-stock products ordered before 16:00 can be shipped on the same day. All reference standards meet the compliance requirements of multiple regulatory systems such as Chinese Pharmacopoeia and FDA, and can fully meet the reference standard use needs of the whole process including API R&D, quality control, registration and declaration.