PHILADELPHIA -- A novel oral drug that interferes with the cascade of molecular events involved in inflammatory responses appears to relieve symptoms in rheumatoid arthritis patients, researchers said here.
The compound, which Pfizer calls CP-690,550, showed effectiveness against placebo in a wide variety of dosages in a Phase 2 study.
In an ongoing Phase III study of the JAK-1-2-3 inhibitor, investigators are using doses of 5 mg twice a day and 10 mg twice a day.
CP-690,550 has been shown to inhibit JAK-3 and JAK-1, with functional selectivity over JAK-2. By inhibiting these enzymes, signaling of multiple cytokines that are involved in a broad spectrum of inflammatory and autoimmune diseases is disrupted.
"This molecule is truly unique," said Joel Kremer, MD, of the Albany Medical College, director of research at The Center for Rheumatology in Albany, N.Y.
Kremer presented the study at the annual meeting of the American College of Rheumatology.
"JAK-inhibition with CP-690,550 is unique in that it has the efficacy of the biologic agents and is an oral drug," he said. Anti-tumor necrosis factor drugs such as adalimumab (Humira) are injected.
Kremer and colleagues enrolled 507 patients with active rheumatoid arthritis in a double-blind, placebo-controlled study. The patients, all of whom were unable to control their disease on methotrexate alone, received either a placebo or one of six dosages of CP-690,550 in a six month study.
The primary endpoint of the study was ACR20 -- an American College of Rheumatology definition indicating a 20% improvement in symptoms -- at week 12. That endpoint was achieved at all doses greater than one milligram.
Kremer also reported on the sustained improvement seen among these patients in the second 12 weeks.
"A dose response for ACR20, ACR50, and ACR70 was observed across the CP-690,550 treatment groups," Kremer said.
http://www.medpagetoday.com/MeetingCoverage/ACR/16506Lynn49.....Thank you for all the current information you provide us. You are such an asset to this board! SharonWow - this sounds promising. Maybe I should look into buying some Pfizer stock in case it's the next blockbuster.