Salts of 3-O-(3',3'-dimethylsuccinyl)Betulinic acid (DSB) are disclosed. Particularly, the preparation, pharmaceutical evaluation, and in vivo bioavailability evaluation of N-methyl-D-glucamine and alkali metal salt forms of DSB are disclosed. Pharmaceutical compositions including these salt forms are used in methods of treating HIV and related diseases. Methods of making the salts of DSB and the pharmaceutical compositions are also provided.