Patent ID: 9056054
Filing Date: 2015-06-16
Classification: A61K

Abstract:
1. A compressed microtablet that is coated with a membrane, the membrane comprising about 16 weight percent to about 80 weight percent, by weight of the membrane, of a water-retardant polymer that is a copolymer of methylmethacrylate and ethylacrylate; and about 5 weight percent to about 50 weight percent, by weight of the membrane, of an additive that is calcium stearate, magnesium stearate, zinc stearate, stearic acid, glyceryl monostearate, hydrogenated vegetable oil, talc, or a combination thereof; wherein said microtablet has a major dimension that is about 0.5 to about 3.0 mm and comprises about 10 to about 30 weight percent, by weight of the microtablet, of at least one opioid antagonist that is dispersed substantially throughout said microtablet, wherein the water retardant polymer is a non-ionic poly(ethylacrylate-co-methacrylate) polymer in which the molar ratio of the ethyl acrylate to methyl methacrylate is about 2:1; wherein the weight gain of the microtablet after the application of the membrane is from about 105 to about 500 weight percent increase; and said compressed microtablet releases no more than about 0.5 weight percent of said opioid antagonist within 36 hours when measured using the USP Apparatus I (Basket) Method at 100 rpm at 37° C. in simulated gastric fluid for one hour followed by simulated intestinal fluid thereafter.