The present document describes a dosage form for delivery of an active ingredient comprising: a first carboxylated polymer having carboxyl groups, having a degree of substitution of at least 0.2, a molecular weight of at least 200 kDa, and at least 30% of said carboxyl groups being complexed with a divalent cation； alone or in a co-complex with at least one of a) a control release polymer chosen from an insoluble polymer or a polymer having a reduced water solubility at 30° C., and a soluble polymer； and b) a second carboxylated polymer having carboxyl groups complexed with a divalent cation. The document also describes processes of making a carboxylated polymer having carboxyl groups, having a degree of substitution of at least 0.2, a molecular weight of at least 200 kDa, and at least 30% of said carboxyl groups being complexed with a divalent cation, and an inclusion complex, a co-complex, or both comprising the same.
