Water insoluble polymer based sustained release formulation
First Claim
1. A sustained release tablet comprising an effective amount of a drug to be released at a controlled rate and a homogenous mixture of three different types of polymers including a water insoluble polymer compound, a pH dependent gelling polymer, and a pH independent gelling polymer, wherein said water insoluble polymer comprises one or more of ethylcellulose and co-polymers of acrylic and methacrylic acid esters.
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Abstract
Sustained release drug formulations contain the pharmaceutical itself and a three component release rate controlling matrix composition. The three components of the matrix composition are (1) water insoluble polymer, such as ethyl cellulose, (2) pH dependent gelling polymer, such as sodium alginate, and (3) a pH independent gelling polymer, such as hydroxypropyl methylcellulose. The drug release rate can be adjusted by changing the amount of one or more of these components of the composition.
216 Citations
16 Claims
- 1. A sustained release tablet comprising an effective amount of a drug to be released at a controlled rate and a homogenous mixture of three different types of polymers including a water insoluble polymer compound, a pH dependent gelling polymer, and a pH independent gelling polymer, wherein said water insoluble polymer comprises one or more of ethylcellulose and co-polymers of acrylic and methacrylic acid esters.
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9. A method of forming a sustained release depot drug dosage form comprising introducing an effective amount of a drug in a tablet comprising and from about 6 to about 60 percent by weight of a homogenous mixture of three different types of polymers including water insoluble polymer compound, a pH independent gelling polymer, and a pH dependent gelling polymer, wherein said water insoluble polymer comprises one or more of ethylcellulose and co-polymers of acrylic and methacrylic acid esters.
Specification