Randomised clinical trial: certolizumab pegol for fistulas in Crohn's disease - subgroup results from a placebo-controlled study

P>Background Treatment options for fistulizing Crohn's disease (CD) are limited. Aim To examine whether fistula closure is maintained at week 26 following treatment with certolizumab pegol. Methods Patients with draining fistulas at baseline from PRECiSE 2 (n = 108) received open-label induction with certolizumab pegol 400 mg at weeks 0 (baseline), 2 and 4. Response was defined as >= 100-point decrease from baseline in the Crohn's Disease Activity Index. Nonresponders (50/108) were excluded. At week 6, responders with draining fistulas (N = 58) were randomised to certolizumab pegol 400 mg (n = 28) or placebo (n = 30) every 4 weeks across weeks 8-24. Fistula closure was evaluated throughout the study, with a final assessment at week 26. Results The majority of patients (55/58) had perianal fistula. At week 26, 36% of patients in the certolizumab pegol group had 100% fistula closure compared with 17% of patients receiving placebo (P = 0.038). Protocol-defined fistula closure (>= 50% closure at two consecutive post-baseline visits >= 3 weeks apart) was not statistically significant (P = 0.069) with 54% and 43% of patients treated with certolizumab pegol and placebo achieving this end point, respectively. Conclusion Continuous treatment with certolizumab pegol improves the likelihood of sustained perianal fistula closure compared with placebo.