Efficacy And Safety Of Adalimumab Biosimilar (Exemptia) In Moderate-To-Severe Steroid-Refractory Ulcerative Colitis Patients: Real-Life Outcomes In Resource-Constrained Setting At 24-Weeks Follow-Up.

Background: Adalimumab (ADA) is approved for the management of lcerative colitis (UC) not responding to conventional therapy. Use of biologics in resource-constrained settings is very challenging. Currently, real-life data on the safety and efficacy of ADA biosimilar (Exemptia) in steroid-refractory UC patients are limited.

Aim and objectives: To assess the efficacy and safety of ADA biosimilar (Exemptia) to treat steroid-refractory difficult-to-treat UC patients in a resource-constrained Indian setting at 24-weeks follow-up.

Materials and methods: This was a retrospective single-center study to evaluate the efficacy and safety of ADA biosimilar (Exemptia) in steroid-refractory UC patients. All the eligible patients who received induction dose of 160 mg at week 0, 80 mg at week 2 and 40 mg at week 4 and 40 mg every 4 weeks as maintenance regimen from 01 September 2017 to 31 Jan 2019 were retrospectively included in this single-center analysis. Those patients who had shown sub-optimal response at 12 weeks received 40 mg every 2 weeks as maintenance therapy. Outcomes in terms of clinical remission, clinical response and mucosal healing were evaluated in the short term at 12 weeks and 24 weeks.

Results: Twenty-five patients were retrospectively included between the time period of 1 September 2017 to 31 July 2018 with a mean age of 35 years. ADA biosimilar was effective in inducing clinical remission in 16% patients at 12 and 24 weeks, clinical response was seen in 48% at week 12 and 44% at week 24. The mean baseline total Mayo score (TMS) for all patients was 10.16 which decreased to a mean score of 5.72 at 12 weeks and 5.52 at 24 weeks with therapy with the decrease of the score being statistically significant both at 12 and 24 weeks (p<0.05). Two patients (8%) developed pulmonary tuberculosis (TB). ADA biosimilar frequency was accelerated to once in 2 weeks in 14 (56%) patients who did not show an optimal response at 12 weeks. Of these 14 patients, 5 were responders and 9 were non-responders at 12 weeks. At 24 weeks, 6 patients showed clinical response and 7 were non-responders, while one patient had developed TB.

Conclusion: ADA biosimilar (Exemptia) therapy is a safe and cost-effective alternative to original biologics in difficult-to-treat UC patients in resource-constrained Indian setting with comparable efficacy. Maintenance therapy at four weekly intervals can be considered in those patients who have shown an early clinical response at 12 weeks to minimize costs, but more studies are needed to confirm the same.