Vedolizumab Is Safe So Far

Natalizumab was the first drug available for treatment of Crohn disease that specifically blocked leukocyte migration and was associated with the rare but devastating occurrence of progressive multifocal leukoencephalopathy. Vedolizumab also blocks leukocyte migration but is specific for the gut.

Researchers analyzed safety data from six industry-funded clinical trials of vedolizumab involving 2830 patients with ulcerative colitis or Crohn disease contributing 4800 person-years of observation on vedolizumab exposure. Results were as follows:

• Risk for adverse events or serious adverse events was not elevated compared with placebo.

• The incidence rates of sepsis and opportunistic infections including tuberculosis and listeria were all ≤0.3%.

• There were four reports of tuberculosis, all pulmonary, and one listeria meningitis infection in a patient who was also on steroids and azathioprine.

• Risk factors for serious infection included prior anti–tumor-necrosis-factor failure and narcotic use in patients with ulcerative colitis and younger age, steroid use, and narcotics in patients with Crohn disease.

• No progressive multifocal leukoencephalopathy occurred, and six or seven cases would be expected if the risk were similar to that associated with natalizumab use (P<0.0012).

• Anti-vedolizumab antibodies occurred in 4% of patients, and concomitant use of azathioprine seemed to reduce the risk for their development.

• Infusion-related reactions occurred in ≤5%, rarely caused discontinuation of the drug, and were considered serious in only three cases.

• Cancer risks were not elevated compared with previously reported risks in patients with inflammatory bowel disease.

• The rate of abnormal liver enzymes was low and similar to that in placebo recipients, and no abnormalities led to discontinuation of study drug.