Dapsone

Leprosy is an infectious disease that has been a long-term focus of global public health efforts. As a core variety of sulfone bacteriostatic agents, dapsone exerts bacteriostatic activity by competitively inhibiting dihydropteroate synthase and blocking the folic acid synthesis pathway of Mycobacterium leprae. It is the basic medication in the WHO-recommended combined chemotherapy regimen for leprosy, and can also be used for the treatment of immune skin diseases such as dermatitis herpetiformis and pustular psoriasis. Its applicable population covers leprosy confirmed patients of all age groups and some patients with refractory skin diseases. Due to its definite efficacy and controllable cost, it is still the basic medication in the leprosy prevention and control system to date.

The global dapsone market size has been stable at around USD 120 million for many years. Driven by the progress of the leprosy elimination program, its growth rate has maintained at 2%-3% in recent years, and the market demand is concentrated in the public health procurement sector. The domestic market is a typical small-variety rigid demand track. At present, only 3 enterprises hold API production approvals, the supply is highly concentrated, and there is no centralized procurement coverage yet. The stability of product supply is the core consideration indicator for downstream preparation enterprises.

The original developer of dapsone is Jacobus Pharmaceutical, with the original brand name Dapsone, and the core compound patent has expired globally. At present, the main dosage form of the original marketed product is tablet, with specifications including 25mg and 100mg, which has been included in the FDA Reference Listed Drug Catalog. In China, there are currently 6 A-status registration numbers for dapsone APIs, and the domestically approved preparation varieties are mainly oral tablets, all of which are generic drugs. (Data as of October 2025, please refer to the official CDE website for the latest information)

CATO can provide a full set of dapsone impurity reference standards, covering all impurity types in the production process and degradation pathways. Most products are in stock, and in-stock products ordered before 16:00 will be shipped on the same day. Meanwhile, they meet the compliance requirements of multiple regulations such as the Chinese Pharmacopoeia and FDA, and can fully support the quality research, registration and declaration, and routine release testing needs of API and preparation enterprises.