Oxybutynin

Overactive bladder (OAB) is a chronic urinary system disease affecting more than 1 billion people worldwide. Symptoms such as urgent urination, frequent urination and urge urinary incontinence severely reduce the quality of life of patients, and antimuscarinic drugs are the first-line treatment option. Oxybutynin is a third-generation M receptor antagonist, which can competitively block the M3 receptor on bladder smooth muscle and reduce the overexcitability of bladder detrusor, while having both local anesthetic and muscle relaxant effects. It is applicable not only to adult patients with idiopathic overactive bladder without definite etiology, but also to children and adolescents with neurogenic bladder dysfunction. It can significantly reduce the frequency of urination and the frequency of urinary incontinence episodes, and is a classic urological drug that has been used clinically for more than 40 years.

At present, the global market size of oxybutynin is about USD 320 million. With the increase in the prevalence of OAB in the elderly population and the improvement in the diagnosis and treatment rate of neurogenic bladder in children, the compound annual growth rate in the past 3 years has remained at 4.1%. The domestic market size is about RMB 270 million, of which oral preparations account for 62%, and the proportion of new dosage forms such as transdermal patches is increasing year by year. In terms of competitive landscape, domestic generic drugs have occupied more than 80% of the market share, and the oral preparations of 13 enterprises have passed the consistency evaluation. Since 2022, the winning bid prices in centralized procurement of multiple provinces have dropped by more than 70% compared with the price of the original research drug, and the accessibility of drugs for patients has been greatly improved.

The original research enterprise of oxybutynin is Janssen Pharmaceuticals, a subsidiary of Johnson & Johnson, with the original research trade name Ditropan®. Its core compound patent in the United States expired in 1990, and the patent for oral preparation in China expired in 2003. The main dosage forms approved by the original research include 5mg conventional tablets, 10mg sustained-release tablets and 3.9mg/day transdermal patches. The conventional tablets have been included in the *Catalogue of Reference Preparations of Chemical Drugs* issued by the NMPA, and are also reference preparations designated by the FDA. Up to now, there are 11 oxybutynin API registration numbers on the API registration platform of China CDE, 7 of which are in Status A, which can supply both domestic preparation production and export markets. The oxybutynin preparations approved for marketing in China cover three dosage forms: conventional tablets, sustained-release tablets and capsules. (Data as of June 2025, please refer to the official website of CDE for the latest information)

CATO can provide a full set of oxybutynin impurity reference standards, covering all categories of process impurities, degradation impurities and isomer impurities. Most products are in stock all year round. Spot orders paid before 16:00 can be shipped on the same day. All products comply with the relevant regulatory requirements of the Chinese Pharmacopoeia, FDA and ICH, and can support the full process needs of API registration and declaration, quality research and quality control in the production process.