Pharmacokinetics of teceleukin (recombinant human interleukin-2) after intravenous or subcutaneous administration to patients with cancer.

Single doses of teceleukin ranging from 0.1 to 30 x 10(6) units were administered to cancer patients as intravenous infusions or subcutaneous injections. Serum samples were analyzed using a bioassay. In general, teceleukin was rapidly eliminated after intravenous administration, with half-lives ranging from 0.24 to 3.3 h. Teceleukin disappeared from serum more slowly following subcutaneous administration, with half-lives of 2.7 to 12.2 h. This finding may be a result of slow absorption from the subcutaneous injection site. Serum concentrations of teceleukin increased in an apparently dose-proportional manner following intravenous administration. When administered subcutaneously, serum concentrations increased with increasing dose but in a manner that was less than dose-proportional, possibly due to dose-dependent bioavailability for subcutaneously administered teceleukin.