Vertex Pharmaceuticals Inc has initiated a 3-month Phase II clinical trial of VX-702, an orally administered small molecule inhibitor of p38 mitogen-activated protein (MAP) kinase, for the treatment of rheumatoid arthritis (RA). Approximately 300 patients with moderate-to-severe RA are scheduled to be enrolled in over 40 centers across Europe. p38 MAP kinase regulates the production of proinflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6), which are known to play roles in chronic inflammatory diseases such as RA, as well as in the acute inflammation characteristic of acute coronary syndrome. The double-blind, randomized, placebo-controlled study will assess two doses of VX-702, administered once-daily without concomitant methotrexate, for 12 weeks. Vertex expects patient enrollment to be completed by the end of 2005.

A Phase I clinical evaluation demonstrated that VX-702 was well-tolerated and has a favorable pharmacokinetic and pharmacodynamic profile. Assessment of laboratory data from a Phase IIa trial of VX-702 in patients with acute coronary syndrome undergoing percutaneous coronary intervention demonstrated a potent and sustained anti-inflammatory effect, as measured by the reduction of serum levels of the biomarker for inflammation, C-reactive protein.

Vertex holds clinical development and commercial rights for VX-702 in the US and Europe, while its strategic partner for the p38 MAP kinase program, Kissei Pharmaceutical Co, Ltd, will financially support the Phase II study.