Pharmaceutical compositions of IL-2

A delivery system, comprising a device for subcutaneous injection, wherein the device is filled with an aqueous liquid pharmaceutical composition wherein the aqueous liquid pharmaceutical composition has a pH from 7.0 to 8.0 and comprises:

• (i) a non-lyophilized interleukin-2 (IL-2) having a specific activity of 8 to 18 MIU/mg of protein, which is present at a concentration of 0.1 to 20 million IU/mL (MIU/mL), (ii) a buffering agent at a concentration from 1 mM to 100 mM, and (iii) an anionic surfactant at a concentration from 0.01 to 5 mg/mL;
• wherein the buffering agent is selected from the group consisting of phosphoric acid, Tris(hydroxymethyl) aminomethane hydrochloride (TRIS-HCl), TRIS-glycine, citrate, borate, citrate phosphate, bicarbonate, glutaric acid, succinic acid, salts thereof, and a combination thereof;
• and
• wherein the anionic surfactant is selected from the group consisting of C8-C20 alkylsulfate salts, lauroyl sarcosinate salts, cholate salts, deoxycholate salts, and a combination thereof.