Clemastine

Allergic reaction is one of the most common immune diseases in clinical practice. Antihistamines are the core treatment option for relieving allergic symptoms. Second-generation antihistamines have become the current mainstream clinical medication due to their milder adverse reaction of drowsiness. Clemastine is a second-generation H1 antihistamine. It can competitively block histamine H1 receptors, inhibit histamine-mediated pathological reactions such as capillary dilation, increased permeability and smooth muscle spasm, and also has certain anticholinergic and sedative effects. Clinically, it is mainly used for the treatment of allergic rhinitis, urticaria, eczema and other allergic skin diseases, and can also be used to relieve allergy-related symptoms of bronchial asthma. It is applicable to adults and children over 6 years old, and is a classic and commonly used drug in the field of allergy.

At present, the global market size of antihistamines has exceeded 8 billion US dollars, of which second-generation antihistamines account for more than 75%. Clemastine occupies a stable share in the over-the-counter antiallergic drug market due to its mature clinical application and good safety. The domestic market size of clemastine preparations is about 230 million yuan, and the compound growth rate in the past three years has remained at 4.1%. At present, the domestic market is dominated by generic drugs, with the original research products accounting for less than 10% of the market. More than 15 enterprises have obtained the approval documents for clemastine preparations, and multiple domestic enterprises have achieved commercial production on the API supply side. The overall market competition is relatively sufficient, and the price system is stable.

The original research enterprise of clemastine is Novartis Pharma, and the original trade name is Tavist. Its core compound patent in the US market expired in 1997, and the compound patent in China has expired. The main dosage forms of the original research product include clemastine fumarate tablets with a specification of 1.34mg (equivalent to 1mg clemastine) and oral solution with a specification of 0.1mg/ml. The original research tablets have been included in the FDA Reference Listed Drug Catalog, and are also included in the China Listed Drug Catalog. Up to now, there are 7 registration entries of clemastine fumarate API on the API registration platform of China CDE, among which 5 are in status "A" (can be used in listed drugs). Multiple preparation varieties such as clemastine fumarate tablets and clemastine fumarate oral solution have been approved for marketing in China. (Data as of June 2025, please refer to the official CDE website for the latest information)

CATO provides a full set of impurity reference standards for clemastine API, which can fully meet the impurity research requirements of different production processes. All products comply with the compliance requirements of multiple regulations such as Chinese Pharmacopoeia and FDA. Most products are in stock. For in-stock products, orders placed before 16:00 can be shipped on the same day, which can fully meet the timeliness requirements of pharmaceutical enterprises in R&D and quality control links.