Extended release pharmaceutical compositions comprising mycophenolate sodium as the active agent, wherein the said composition exhibits a characteristic release profile when subjected to in-vitro dissolution study, and wherein said mycophenolate sodium is released in a sustained manner in-vivo for a prolonged duration in such quantities that substantially alleviates or at least reduces the chances of causing any associated gastrointestinal side effect(s) without compromising the bioavailability of the said active agent are provided. The present invention also provides process of preparing dosage form compositions and prophylactic and/or therapeutic methods of using such dosage form. The compositions of the present invention are useful for the management such as prophylaxis, amelioration and/or treatment of immunosuppressant indicated disease(s)/disorder(s) especially for the treatment or prevention of organ, tissue or cellular allograft or xenograft rejection, e.g. after transplant, or the management of immune-mediated diseases (autoimmune diseases).
