Microbeads of diltiazem, a process for their manufacture and a substained-release pharmaceutical composition containing them
US5344657A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 1993 |
| Grant date | Sep 6, 1994 |
| Priority date | — |
| Expiry date | Apr 5, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/5078
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The microbeads are composed of a core containing the active ingredient and a microporous membrane, insoluble in aqueous medium, consisting of a film-forming polymer, a plasticizer and a filling material. The membrane has a thickness such that diltiazem is released in vitro at an approximately constant rate for at least 6 hours after a latent period of less than one hour. The active ingredient can be intimately mixed with the core or included in a polyvinyl pyrrolidone layer coating an inert grain. The sustained-release microbeads are formed by application to the core of a dispersion of the constituents of the membrane in a solvent and evaporation of the solvent. The pharmaceutical compositions consist of capsules containing the microbeads. They are administered orally one or twice per day, depending on the dose, for the treatment of angina or hypertension.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.