Chloroquine

As a cornerstone drug in the classic antimalarial field, chloroquine is a 4-aminoquinoline derivative. Its mechanism of action is to inhibit the heme polymerase activity of Plasmodium, preventing Plasmodium from converting toxic heme into non-toxic hemozoin, thereby causing the death of Plasmodium. In addition to the antimalarial indication, subsequent clinical studies have also found that it has an immunomodulatory effect, and it is also used for the treatment of autoimmune diseases such as rheumatoid arthritis and lupus erythematosus. The applicable population covers malaria-susceptible people of all age groups and patients with autoimmune diseases who meet the indications, and its clinical application span has exceeded 70 years.

The stable demand in the global antimalarial drug market supports chloroquine to maintain a stable market volume for a long time. At present, its annual market size is about US$180 million. Driven by the rising demand for malaria prevention and control in tropical regions and the expansion of applications in the field of autoimmune diseases, its compound growth rate in the past three years has remained at 4.2%. In terms of competitive landscape, as the core patents have long expired, generic production dominates the market. China and India are the world's most important producers of chloroquine API, with production capacity accounting for more than 85% of the global total. In addition to meeting the domestic demand for antimalarial reserves, more than 70% of the products of domestic enterprises are exported to high malaria incidence regions such as Africa and Southeast Asia.

The original research enterprise of chloroquine is Bayer, and the original research trade name is Aralen. The core compound patent expired in 1977. At present, the mainstream marketed dosage forms include tablets and injections. The common specification of tablets is 250mg (equivalent to 300mg of chloroquine phosphate), and the specification of injections is 5ml:322mg of chloroquine phosphate. The original research dosage form of this variety has been included in the Reference Listed Drug Catalogue published by the FDA, and is also included in the *Catalogue of Reference Preparations for Chemical Drugs* of China. In terms of domestic API registration, at present, more than 10 enterprises have obtained A status for their chloroquine phosphate API through CDE registration, and the total number of domestically approved marketed chloroquine phosphate tablets and injections exceeds 30. (Data as of June 2025, please refer to the official CDE website for the latest information)

CATO can provide a full set of impurity reference standards for chloroquine API. The products meet the compliance requirements of multiple regulatory systems such as the Chinese Pharmacopoeia and FDA. Most impurities can be supplied from stock. For in-stock products, orders placed before 16:00 can be shipped on the same day, which can fully meet the full-process needs of API enterprises in R&D, production and quality testing.