Patent · US Expired

Devices for the controlled release of active substances, as well as process for the preparation thereof

US4708874A · kind A · utility

106Cited by
15References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 10, 1986
Grant dateNov 24, 1987
Priority date
Expiry dateMar 10, 2006

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61K9/2077
  • WIPO fieldPharmaceuticals
  • WIPO sectorChemistry

Abstract

The invention relates to a device for the controlled release of one or more active ingredients to a liquid, particularly a controlled release pharmaceutical tablet obtained by compressing a mixture of two granulates in a weight ratio of 30:70 to 70:30, said granulates having particle sizes of 0.4-2.0 mm. One of the granulates, the restraining phase granulate, comprises one or more active ingredients dispersed in a matrix of an insoluble substance, and the other granulate, the housing phase granulate, comprises a soluble material and a penetration rate limiting material, one material optionally having both functions. In the compressed device, the granulates form two distinct phases, each of which is continuous. The housing phase fills large continuous pores in the restraining phase. A zero-order release rate can be obtained with the devices.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.