US Patent 9408823 Benzonatate modified release solid tablets and capsules

A 12-hour anti-tussive modified release solid tablet or capsule is described which comprises a benzonatate adsorbate in a matrix with a sufficient amount of one or more pharmaceutically acceptable modified release pH-independent, substances to provide a 12-hour modified release profile to the benzonatate, wherein there is substantially no benzonatate release from the tablet or capsule 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.