Topiramate

As a classic anti-epileptic drug commonly used in clinical practice, topiramate is a new type of sulfamate anticonvulsant. It exerts its pharmacological effects through multiple mechanisms of action, including blocking voltage-dependent sodium channels, enhancing the activity of γ-aminobutyric acid A receptors, and antagonizing the glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. In addition to being used for the treatment of partial-onset seizures and generalized tonic-clonic seizures in adults and children over 2 years old, it has also been approved for the prophylactic treatment of migraine. It has also shown potential clinical value in the fields of bipolar disorder, neuropathic pain, etc., and is a commonly used basic drug in the field of central nervous system disease treatment.

At present, the global topiramate market size is stable at around USD 1.2 billion, of which generic drugs account for more than 90%. The annual sales in the Chinese market are approximately RMB 1.8 billion, with a compound annual growth rate maintained at 3.7%. The domestic market competition pattern is relatively concentrated, with local generic manufacturers accounting for more than 70% of the market share. As the seventh batch of national centralized drug procurement included topiramate oral regular-release dosage forms in the scope of centralized procurement, the average price reduction of winning products reached 73%, clinical accessibility has been greatly improved, and the demand for upstream API has shown a steady upward trend.

The original research enterprise of topiramate is Johnson & Johnson of the United States, with the original brand name "Topamax". Its core compound patent expired globally in 2009. The original research dosage forms include 25mg, 50mg, 100mg tablets and 15mg, 25mg capsules, which have been included in the *Catalogue of Chemical Reference Preparations* of China and also listed in the FDA Reference Preparations Catalogue. According to the domestic API registration platform, nearly 30 enterprises have had their topiramate API passed the registration review of CDE (status A) up to now. The domestically approved topiramate preparations cover tablets, capsules and other dosage forms for routine clinical use. (Data as of October 2024, please refer to the official CDE website for the latest information.)

In response to the quality control requirements for the upstream and downstream R&D and production of topiramate, CATO provides a full set of impurity reference standards for this API, which can fully cover research scenarios such as synthesis process impurities and degradation impurities. Most of the products are in stock, and in-stock products ordered before 16:00 will be shipped on the same day. All reference standards comply with the regulatory requirements of the Chinese Pharmacopoeia, FDA and other regulations, and can effectively support enterprises to complete the whole process of API registration and declaration, quality stability research and other work.