Integrin Blocker Approved for Inflammatory Bowel Disease

The Food and Drug Administration has approved vedolizumab (Entyvio) for the treatment of Crohn's disease and ulcerative colitis in patients who have not responded to corticosteroids, immunomodulators, or tumor necrosis factor blocker medications.

The approval is based on five placebo-controlled trials involving about 2,400 patients. Common side effects include joint pain, headache, nausea, and fever. More serious adverse events include infections, hypersensitivity and infusion-related reactions; and hepatotoxicity.

The medication is an integrin receptor blocker that inhibits influx of inflammatory cells into the gastrointestinal tract by disabling one specific signaling molecule, without inducing the systemic immunosuppression that characterizes as natalizumab (Tysabri), which has also been approved for Crohn's disease as well as multiple sclerosis.

No cases of progressive multifocal leukoencephalopathy (PML), which have affected a few patients on natalizumab, have arisen in clinical trials of vedolizumab. However, the FDA will remain vigilant for PML in postmarketing studies of vedolizumab and expedited adverse event reporting.