Trial of CRP Inhibitor for RA Halted

Isis Pharmaceutical has announced that it is halting a trial of its experimental rheumatoid arthritis (RA) drug ISIS-CRP, due to lack of significant efficacy compared to placebo in Phase II trials. The drug targets C-reactive protein (CRP), which is associated with inflammation.

The Phase IIrandomized, placebo-controlled, trial involved 51 RA patients with chronically elevated CRP, who received 100 mg, 200 mg or 400 mg doses of the experimental drug or placebo for 12 weeks. ISIS-CRP produced dose-dependent reductions in CRP early in treatment as well as improvents in as ACR20 and ACR50 scores measuring RA activity.

However, the responses were not significantly better than those in the placebo group.

The drug continues to be tested as a treatment for atrial fibrillation.