The disclosure relates generally to polyglutamated antifolates, formulations containing liposomes filled with the polyglutamated antifolates, methods of making the polyglutamated antifolates and liposome containing formulations, and methods of using the polyglutamated antifolates and liposome containing formulations to treat hyerproliferative disorders (e.g., cancer) and disorders of the immune system (e.g., an autoimmune disease such as rheumatoid arthritis).