Abstract: Disclosed herein are pharmaceutical compositions comprising carboxyalkylcellulose esters for delivery of pharmaceutically active substances having low solubility in a medium such as water, an acidic aqueous buffer, a neutral aqueous buffer, or a basic aqueous buffer. Also disclosed are methods for making pharmaceutical compositions and methods of administering the compositions.

Abstract: Disclosed herein are pharmaceutical compositions comprising carboxyalkylcellulose esters for sustained delivery of pharmaceutically active substances. The composition comprises: at least one pharmaceutically active agent, and at least one carboxyalkyl cellulose ester comprising an anhydroglucose repeat unit having the structure: wherein: R1-R6 are each independently selected from —OH, —OC(O)(alkyl), and —O(CH2)xC(O)OH, and pharmaceutically acceptable salts thereof, wherein x ranges from 1-3, a degree of substitution per anhydroglucose of —OH ranges from 0.1 to 0.7, a degree of substitution per anhydroglucose of —C(O)(alkyl) ranges from 0.1 to 2.7, and a degree of substitution per anhydroglucose of —O(CH2)xC(O)OH ranges from 0.2 to 0.75, and wherein in pharmaceutically acceptable media, the composition exhibits sustained release of the at least one pharmaceutically active agent.