The presently disclosed and claimed inventive concept(s) relates to a polymer for enhancing drug performance and improving processability. Specifically, the polymer comprises hydroxypropyl methyl cellulose acetate succinate (HPMC-AS). On the HPMC-AS, the percentage of total succinoyl degree of substitution is less than 12% at C6-OH position and greater than 53% at C3-OH, and the percentage of total acetyl degree of substitution is greater than 32% at C6-OH position.