Modified-release metronidazole compositions and methods for making and

Abstract

Pharmaceutical compositions having a modified release profile for once daily dosing of metronidazole, methods for making the pharmaceutical compositions, and methods for treating a microbial infection with once daily dosing of the pharmaceutical compositions of the invention are provided. The compositions given once daily exhibit substantial bioequivalence to immediate release metronidazole given three times per day. The compositions of the invention comprise: (a) a first portion of metronidazole which is about 59 wt % to about 79 wt % metronidazole; (b) about 1.5 wt % to about 3.0 wt % of an aqueous insoluble poly(meth)acrylic acid ester copolymer which is aqueous permeable, aqueous expandable and pH-independent; (c) about 0.1 wt % to about 2.0 wt % detackifier; (d) 0 to about 23 wt % of a first aqueous soluble pharmaceutical diluent; (e) 0 to about 23 wt % of a second aqueous soluble diluent which is suitable for forming a pharmaceutical tablet when compressed with the granules of (a), the second aqueous soluble diluent being the same as or different from the first aqueous soluble diluent; (f) 0 to about 20 wt % of a second portion of metronidazole; (g) 0 to about 0.2 wt % glidant; and (h) 0 to about 2 wt % lubricant; wherein the composition comprises metronidazole containing granules comprising (a), (b), (c) and (d), wherein the sum of the weight percentages of metronidazole provided by (a) and (f) is between about 72 wt % and about 79 wt %, and wherein the sum of the weight percentages of the aqueous soluble diluent provided by (d) and (e) is between about 16 wt % and about 23 wt %.