Benzonatate modified release solid tablets and capsules

A 12-hour anti-tussive modified release solid oral tablet comprising:

• a core and a reverse enteric coating over said core,
• wherein said core comprises benzonatate in a matrix, wherein said matrix is a homogenous solid dispersion comprising (a) an adsorbate comprising benzonatate and a silica, wherein the weight percentage of benzonatate in the adsorbate is about to 50% by weight benzonatate to about 75% by weight benzonatate, based on the weight of the adsorbate, (b) about 4% to about 20% of a hydrophilic or hydrophilic matrix forming material, by weight based on the weight of the core, and wherein the ratio of benzonatate adsorbate to polymer is about 8:1 to about 1:1;
• and about 5% to about 20% by weight of a reverse enteric coating wherein the coating weight percentage is based on the total coated tablet prior to any optional seal coat, wherein there is substantially no benzonatate release from the tablet in the buccal cavity or esophagus and no more than about 25% release of the benzonatate within 1 hour as determined in an in vitro dissolution assay.

A 12-hour anti-tussive modified release solid oral tablet or capsule composition comprising benzonatate in a matrix, wherein said matrix is a homogenous solid dispersion comprising (a) an adsorbate comprising benzonatate and a nonmetallic based silica and (b) about 4% w/w to about 20% w/w glyceryl behenate, wherein there is substantially no benzonatate release from the composition in the buccal cavity and no more than about 25% release of the benzonatate within 1 hour as determined in an in vitro dissolution assay.

A 12-hour benzonatate modified release solid tablet comprising a homogenous dispersion comprising a benzonatate silicate adsorbate and at least one pharmaceutically acceptable modified release pH-independent, high melt temperature, matrix-forming water-insoluble wax or waxy substance in an amount effective to provide a 12-hour modified release profile to the benzonatate, wherein said solid tablet further comprises a reverse enteric coating over said benzonatate-silicate adsorbate-matrix, wherein there is substantially no benzonatate release from the composition in the buccal cavity and no more than about 25% release of the benzonatate within 1 hour as determined in an in vitro dissolution assay.