Claims for Patent: 5,190,765

Summary for Patent: 5,190,765

Title:	Therapy delayed
Abstract:	A dosage form is disclosed comprising means for delaying the delivery of drug from the dosage form following the administration of the dosage form to a patient in need of drug therapy.
Inventor(s):	Jao; Frank (San Jose, CA), Wong; Patrick S. L. (Palo Alto, CA), Huynh; Hoa T. (Fremont, CA), McChesney; Kathy (Cupertino, CA), Wat; Pamela K. (Santa Clara, CA)
Assignee:	ALZA Corporation (Palo Alto, CA)
Application Number:	07/799,451
Patent Claims:	1. A dosage form for the delayed-delivery of a drug to a fluid environment of use, wherein the dosage form comprises: (a) drug composition comprising a dose of 0.05 ng to 1.5 g of a calcium channel blocker drug, and a polymer comprising a molecular weight up to 1,000,000 and a rate of hydration in the presence of fluid that enters the dosage form to change from a non-dispensable phase to a dispensable phase; (b) a push composition that imbibes fluid and expands, whereby the push composition pushes the calcium channel blocker drug composition from the dosage form; (c) a wall that surrounds the drug and push compositions, said wall comprising a semipermeable cellulose polymer composition permeable to the passage of fluid present in the environment of use, and 15 wt % to 85 wt % of a different cellulose polymer comprising a 8,500 to 4,000,000 molecular weight for slowing the rate of fluid passage through the semipermeable cellulose polymer composition of the wall; (d) at least one exit means in the wall for delivering the drug from the dosage form; and wherein the dosage form is characterized by: (e) a subcoat for the delayed-delivery of drug, which subcoat comprises a hydroxyalkylcellulose polymer possessing a 8,500 to 4,000,000 molecular weight that surrounds the drug and push composition and is positioned between the inside surface of the wall and the drug and push composition; and characterized further by: (f) a delayed-delivery of 30 minutes to 7 hours is provided by (1) the polymer in the drug composition, (2) the polymer in the wall composition and (3) the polymer in the subcoat operating in conjunction, whereby through the combined operations of (1), (2) and (3) a delayed-delivery of the calcium channel blocker drug is provided by the dosage form. 2. The dosage form for the delayed-delivery of the drug according to claim 1, wherein the subcoat hydroxyalkylcellulose is hydroxyethylcellulose and the calcium channel blocker drug is verapamil. 3. The dosage form for the delayed-delivery of the drug according to claim 1, wherein the drug is a member selected from the group consisting of a calcium channel blocker and its pharmaceutically acceptable derivatives. 4. The dosage form for the delayed-delivery of the drug according to claim 1, wherein the drug is a member selected from the group consisting of nifedipine, nilvadipine, flunarizine, nimodipine, diltiazem, nicardipine, nitredipine, nisoldipine, felodipine, amlodipine, cinnarizine, and fendiline. 5. The dosage form for the delayed-delivery of the drug according to claim 1, wherein the calcium channel blocker drug is replaced by a member selected from the group consisting of angiotensin converting enzyme inhibitor, ramipril, fosinopril, altiopril, benazepril, libenzapril, alacepril, cilazapril, cilazaprilat, perindopril, zofenopril, enalapril, lisinopril, imidapril, spirapril, rentiapril, captopril, delapril, olindapril, indolapril, and quinapril. 6. The dosage form for the delayed-delivery of the drug according to claim 1, wherein an external, instant dose of drug is in contact with the wall.