Pharmacokinetics of CTLA4Ig fusion protein in healthy volunteers and patients with rheumatoid arthritis.

Aim: To evaluate single-dose and multiple-dose pharmacokinetics of cytotoxic T-lymphocyte-associated antigen 4 fusion protein (CTLA4Ig) in healthy volunteers and patients with rheumatoid arthritis (RA).

Methods: The clinical trials included two phase I open studies: study 1 was an open-label dose-escalation study in 27 healthy volunteers and study 2 was a single-group, open-label study in patients with rheumatoid arthritis. In study 2, 9 patients were arranged to receive 10 mg/kg of CTLA4Ig at 0, 2, 4, 8, 12, and 16 weeks.