Syk kinase inhibitors-a new class of oral drugs for the treatment of rheumatoid arthritis (RA)-produces a rapid reduction in disease activity, according to results of a phase II trial presented during the October 2008 annual meeting of the American College of [IMGCAP(1)]Rheumatology. Syk kinase, an intracellular protein that is thought to be a key player in the activation of immune cells, was randomly administered, along with a placebo, to 189 patients with active RA at doses of 50, 100, or 150 mg twice daily. The two highest doses were associated with a significantly superior response compared with placebo. Additionally, one-third of the patients on 100 mg and half of those taking 150 mg achieved remission. Adverse side effects were dose-related and included diarrhea and neutropenia (susceptibility to bacterial infection). Larger phase II studies are now in progress to determine the best dose, the long-term response rate, and patient tolerability.