Trimethoprim

For the clinical treatment of bacterial infectious diseases, the application of synergists is an important means to improve antibacterial efficacy and reduce the risk of drug resistance. Trimethoprim is an antibacterial synergist belonging to the dihydrofolate reductase inhibitor class. It reversibly inhibits the activity of bacterial dihydrofolate reductase, blocks the synthesis of tetrahydrofolic acid, and interferes with the production process of bacterial nucleic acids and proteins. When used alone, it has certain bacteriostatic activity against common pathogenic bacteria such as Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae. When combined with sulfonamides, it can exert a dual blocking effect on bacterial folate metabolism, and the antibacterial activity can be enhanced by several times to dozens of times. Clinically, it is mainly used for the treatment of urinary tract infections, respiratory tract infections, intestinal infections, and acute otitis media in children caused by susceptible bacteria, and can also be used as a component of combination therapy for drug-resistant malaria, with the applicable population covering adult and pediatric patients with infections.

As a classic antibacterial synergist that has been in clinical application for more than 50 years, the global market size of trimethoprim is stable at around USD 320 million, with a compound annual growth rate maintained at 2.1%, and the overall market demand is relatively rigid. The global supply of trimethoprim API is dominated by Chinese enterprises, with domestic production capacity accounting for more than 85% of the total global production capacity. At present, nearly 20 enterprises have obtained the production approval documents for trimethoprim API, the industry competition is sufficient, and the price system has remained stable for a long time. After the implementation of the volume-based procurement policy, the clinical dosage of downstream compound sulfamethoxazole preparations has increased steadily, further driving the growth of demand for upstream APIs.

The original research enterprise of trimethoprim is Roche, with the original brand name Proloprim. The compound patent in the US market expired in 1979, and all core preparation patents expired before 1990. Currently, the main approved dosage forms include tablets and injections. The common oral dosage form specifications are 100 mg and 200 mg, and the injection specification is 2 ml:0.1 g. The original research preparation has been included in the FDA Reference Listed Drug Directory, and the original research product has not been imported into China. At present, the domestically marketed preparations such as compound sulfamethoxazole tablets and trimethoprim tablets all use domestic generic drugs as reference preparations. As of now, there are 11 trimethoprim API registration numbers on the CDE API registration platform, 8 of which have obtained the A status and can be legally supplied to domestic preparation manufacturers. (Data as of June 2025, please refer to the official CDE website for the latest information)

CATO provides a full set of trimethoprim impurity reference standards. Most of the products are in stock. For in-stock products, orders placed before 16:00 will be shipped on the same day. The products meet the compliance requirements of multiple regulations including the Chinese Pharmacopoeia and FDA, and can fully meet the multi-scenario needs of API enterprises such as quality research, impurity control, and registration and declaration.