Introduction Current medical options for patients with refractory steroid-dependent, chronic-active ulcerative colitis (UC) are limited. Immunosuppressants (IS) and biologics carry risks of severe side effects and patients may not respond. The efficacy of of Granulocyte, Monocyte/Macrophage adsorptive (GMA) apheresis with Adacolumn® is supported by an increasing number of randomised controlled trials. The present study intended to generate further data to document efficacy and identify subpopulations of refractory UC that may benefit from GMA apheresis.

Methods This was an uncontrolled, open-label, multicenter trial conducted in the UK, France and Germany. Consecutive eligible patients (age >18 <75 years) with steroid-dependent active UC, a Rachmilewitz (CAI) index ≥6, an Endoscopic Activity Index (EAI) ≥4, and insufficient response or intolerance to IS and/or biologicals were included. Patients received at least 5 weekly GMA aphereses. Evaluation visits were planned at Week 12, 24 and 48. The primary endpoint was the remission rate (CAI ≤4) at Week 12 in the Intention-to-treat (ITT) population.

Results We report interim results from the 12 Week visit. The ITT population comprised 84 enrolled and treated patients at cutoff date. At Week 12, 33 (39.3%) subjects had achieved remission. For 30 patients with prior failure of IS and/or biologicals, the remission rate was 30%. Secondary efficacy parameters were clinical response with reduction in CAI of ≥3 (47 or 55.9%), steroid-free remission (23%) and steroid-free response (36%). In remitters, EAI dropped from 8.2 to 4.4; in responders from 8.6 to 5.3. Quality of Life improved in parallel. Most subjects had Adverse Events (AEs) of mild or moderate intensity. Six (7.1%) of 85 subjects in the Safety Population experienced serious (SAEs), all in the treatment-emergent period; however none was considered related to study treatment. No new safety signals were seen.

Conclusion This study describes a larger cohort of steroid-dependent moderate-severe active UC patients intolerant or refractory to IS and/or biologicals treated with GMA apheresis. Apheresis was safe and showed benefit in over half of these patients and remission in 39.3% at week 12. Leukocyte aphaeresis (Adacolumn) for IBD has been reviewed by NICE as suitable for carefully selected patients with IBD, and these results help define this sub-group. Further controlled studies are needed.

Disclosure of Interest None Declared.