Multiparticulate controlled porosity osmotic pump
US4886668A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1987 |
| Grant date | Dec 12, 1989 |
| Priority date | — |
| Expiry date | Sep 24, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K31/55
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The instant invention is directed to a multiparticulate osmotic pump, for the controlled release of diltiazem L-malate to an environment of use, said pump comprising: PA0 (I) a carrier medium which does not maintain its integrity in the environment of use; PA0 (II) a multiple of tiny osmotic pump elements each comprising: PA0 (A) a core comprises diltiazem L-malate and an effective buffering amount of sodium bitartrate surrounded by PA0 (B) a rate controlling water insoluble wall, having a fluid permeability of 6.96.times.10.sup.-18 to 6.96.times.10.sup.-14 cm.sup.3 sec/g and a reflection coefficient of less than 0.5, prepared from: PA1 (i) a polymer permeable to water but impermeable to solute and PA1 (ii) 0.1 to 60% by weight, based on the total weight of (i) and (ii), of at least one pH insensitive pore forming additive dispersed throughout said wall, wherein the total amount of diltiazem L-malate in all of the osmotic pump elements is a therapeutically effective amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.