Background Cellular adhesion molecules play an important role in the pathogenesis of ulcerative colitis, making selective blockade of these molecules a promising therapeutic strategy. Vedolizumab, a recombinant humanized IgG1 monoclonal antibody, inhibits adhesion and migration of leukocytes into the gastrointestinal tract by binding the alpha4beta7 integrin. Animal studies have suggested that vedolizumab may be a useful therapy for ulcerative colitis. This updated systematic review summarizes the current evidence on the use of vedolizumab for induction and maintenance of remission in ulcerative colitis. Objectives The primary objectives were to determine the efficacy and safety of vedolizumab used for induction and maintenance of remission in ulcerative colitis. Search methods A computer-assisted search for relevant studies (inception to 15 June 2014) was performed using PubMed, MEDLINE, EMBASE and CENTRAL. References from published articles and conference proceedings were searched to identify additional citations. Selection criteria Randomized controlled trials comparing vedolizumab to placebo or a control therapy for induction or maintenance of remission in ulcerative colitis were included. Data collection and analysis Two authors independently extracted data and assessed the risk of bias for each trial. The primary outcomes were failure to induce clinical remission and relapse. Secondary outcomes included failure to induce a clinical response, failure to induce endoscopic remission, failure to induce an endoscopic response, quality of life, adverse events, serious adverse events and withdrawal due to adverse events. We calculated the relative risk (RR) and 95% confidence intervals (CI) for each outcome. Data were analyzed on an intention-to-treat basis. The overall quality of the evidence supporting the outcomes was evaluated using the GRADE criteria. Main results Four studies (606 patients) were included. All of the studies were rated as having a low risk of bias. Pooled analyses revealed that vedolizumab was significantly superior to placebo for induction of remission, clinical response, and endoscopic remission and prevention of relapse. After 4 to 6 weeks of therapy 77% (293/382) of vedolizumab patients failed to enter clinical remission compared to 92% (205/224) of placebo patients (RR 0.86, 95% CI 0.80 to 0.91; 4 studies 606 patients). After 6 weeks of therapy 48% of vedolizumab patients failed to have a clinical response compared to 72% of placebo patients (RR 0.68, 95% CI 0.59 to 0.78; 3 studies 601 patients). After 4 to 6 weeks of therapy 68% of vedolizumab patients failed to enter endoscopic remission compared to 81% of placebo patients (RR 0.82, 95% CI 0.75 to 0.91; 3 studies, b583 patients). After 52 weeks of therapy, 54% of vedolizumab patients had a clinical relapse compared to 84% of placebo patients (RR 0.67, 95% CI 0.59 to 0.77; 1 study, 373 patients). One small study (28 patients) found no statistically significant difference in endoscopic response (RR 1.00, 95% CI 0.62 to 1.61). GRADE analyses indicated that the overall quality of the evidence for the primary outcomes was high for induction of remission and moderate for relapse (due to sparse data 246 events). There was no statistically significant difference between vedolizumab and placebo in terms of the risk of any adverse event (RR 0.99, 95% CI 0.93 to 1.07), or serious adverse events (RR 1.01, 95% CI 0.72 to 1.42). There was a statistically significant difference in withdrawals due to adverse events. Six per cent of vedolizumab patients withdrew due to an adverse event compared to 11% of placebo patients (RR 0.55, 95% CI 0.35 to 0.87; 2 studies, 941 patients). Adverse events commonly reported across the studies included: worsening ulcerative colitis, headache, nasopharyngitis, upper respiratory tract infection, nausea, and abdominal pain. Authors' conclusions Moderate to high quality data from four studies shows that vedolizumab is superior to placebo for induction of clinical remission and response and endoscopic remission in patients with moderate to severely active ulcerative colitis and prevention of relapse in patients with quiescent ulcerative colitis. Moderate quality data from one study suggests that vedolizumab is superior to placebo for prevention of relapse in patients with quiescent ulcerative colitis. Adverse events appear to be similar to placebo. Future trials are needed to define the optimal dose, frequency of administration and long-term efficacy and safety of vedolizumab used for induction and maintenance therapy of ulcerative colitis. Vedolizumab should be compared to other currently approved therapies for ulcerative colitis in these trials.
