Topiroxostat is a drug for the treatment of gout and hyperuricemia. It was approved for use in Japan in June 2013. Topiroxostat is a xanthine oxidase inhibitor which reduces serum urate levels. Chemically it is a non-purine selective inhibitor of xanthine oxidase developed for oral administration; the active pharmaceutical ingredient is manufactured as a crystalline solid for formulation into immediate release film coated tablets. In clinical development and postmarketing literature Topiroxostat has shown dose dependent serum urate lowering and is dosed orally under physician supervision; pharmacokinetic summaries report rapid absorption following oral dosing, hepatic metabolism to inactive or less active metabolites, and renal and biliary excretion of metabolites. For formulation and development considerations the API is typically controlled for assay, polymorphic form, bulk density, particle size distribution, residual solvents and water content to ensure consistent tableting and bioavailability.
Parent: Topiroxostat
Typical commercial quality control of Topiroxostat API monitors process related and degradation impurities including unreacted starting materials, positional isomers, simple oxidative metabolites such as N-oxide and hydroxylated products, dealkylated species and ring-opened or hydrolytic degradants. A common manufacturer specification set used in regulatory dossiers and supplier certificates of analysis is assay 98.0 to 102.0 percent by validated HPLC, individual unspecified impurities not greater than 0.10 percent w by w, any single identified related compound controlled to 0.20 percent w by w or lower, and total impurities limited to 0.50 percent w by w. Additional controls include residual solvents in accordance with ICH Q3C, elemental impurities in accordance with ICH Q3D, water content limits appropriate to the crystalline form, and limits for genotoxic impurities addressed per ICH M7 risk assessment. Specific impurity identities and structural assignments are established by suppliers through forced degradation and route of synthesis studies and are listed in the supplier impurity profile supplied with technical batches.
Topiroxostat is indicated for the reduction of elevated serum urate levels in patients with hyperuricemia and for the management of gout by inhibiting xanthine oxidase and thereby lowering uric acid production. Use and dosing require prescription and monitoring by a physician.
Topiroxostat is not approved by the United States Food and Drug Administration. It received regulatory approval in Japan in June 2013. Approval status in other regions varies and should be checked with local regulatory authorities.
Topiroxostat is marketed as prescription oral tablets, generally as immediate release film coated tablets. Marketed strengths vary by country and product, with suppliers commonly providing multiple strengths to allow physician titration; consult local prescribing information or the product label for available strengths in a given market.
Pricing for a Topiroxostat 40 mg tablet varies by country, distribution channel, brand, reimbursement and local pharmacy. Current retail or wholesale prices are not provided here. For up to date pricing contact local pharmacies, wholesalers or the manufacturer or consult national drug price lists and reimbursement databases.
