Safety, tolerability, pharmacokinetics, and pharmacodynamics of single-dose antiinterleukin- 18 mAb GSK1070806 in healthy and obese subjects.

OBJECTIVE: To investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of GSK1070806, a novel IgG1 mAb that neutralizes human interleukin (IL)-18. METHODS: In this first-timein-human (FTIH) study, cohorts of healthy and obese subjects were randomly allocated to receive single doses of GSK1070806 (0.008 - 10 mg/kg) or placebo. Blood was sampled ≤ 274 days post-dosing, and safety monitored. RESULTS: GSK1070806 was generally well tolerated. The most common AEs were nasopharyngitis and headache, arising as frequently in the placebo as in the active drug groups; most AEs were mild to moderate and unrelated to dose level. There were no allergic, delayed-type hypersensitivity, or infusion-related reactions and the incidence of immunogenicity was low. GSK1070806 plasma pharmacokinetic profiles were comparable in healthy and obese subjects; there was no major deviation from dose proportionality for AUC(∞) and C(max) although a trend for dose-dependent increase in t(1/2) was observed. Serum drug-bound IL-18 levels increased post-dosing and were sustained for a long time-period following GSK1070806 administration. Ex-vivo whole blood assay demonstrated prolonged pharmacological activity of GSK1070806 as determined by its primary immunological mechanism of action, inhibition of IL-18-induced IFN-γ production. CONCLUSION: GSK1070806 warrants clinical investigation in patients.