Details for Patent: 4,925,860

Summary for Patent: 4,925,860

Title:	Stable pharmaceutical composition of 3-(hydroxymethyl)-5,5-diphenylhydantoin disodium phosphate ester
Abstract:	Described is a stable pharmaceutical composition of 3-(hydroxymethyl-5,5-diphenylhydantoin disodium phosphate ester, the prodrug of 5,5-diphenylhydantoin (phenytoin) a commonly used drug for the treatment and management of epilepsy and other types of convulsive states. It has been found that degradation of the prodrug to phenytoin can be controlled by controlling the pH of the composition. Controlling the pH to between 8.3 to 9.4 results in the production of diphenylglycinamide as the primary degradant and minimization of degradation to phenytoin. If the pH is maintained at a lower or higher value, then the degradation pattern changes, with earlier than expected product failure.
Inventor(s):	Herbranson; Dale E. (Lindenhurst, IL), Speicher; Earl R. (Buffalo Grove, IL), Rosenberg; Leonard S. (Flemington, NJ)
Assignee:	E. I. Du Pont de Nemours and Company (Wilmington, DE)
Application Number:	07/356,948
Patent Claim Types: see list of patent claims	Use; Composition; Formulation; Compound;

Drugs Protected by US Patent 4,925,860

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

International Family Members for US Patent 4,925,860

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	135907
Australia	5670490
Australia	632130
Canada	2067122