Biosimilar Adalimumab, Exemptia, Has Limited Efficacy in Treating Ulcerative Colitis

A retrospective, observational study, newly published in Intestinal Research, reports the first real-world experience with India’s first available biosimilar adalimumab, Exemptia (made by Zydus Cadila), in patients with ulcerative colitis (UC). The researchers found that the biosimilar offered only limited efficacy when used for induction of remission in patients with moderate to severe UC that was refractory to treatment with steroids.

In India, the use of biologic drugs has been limited by the high cost of treatment; the availability of a biosimilar adalimumab, referencing Humira, has expanded access to treatment. However, few data on the safety and efficacy of Exemptia have been available thus far, and concerns about the acquisition or reactivation of tuberculosis in patients in developing countries, like India, have persisted.

The research team sought to evaluate the treatment outcomes of patients receiving the biosimilar adalimumab for moderate to severe UC. The study, conducted between June 2015 and December 2016, included 29 patients who each received a total of 5 subcutaneous injections of Exemptia (160 mg at week 0, 80 mg at week 2, and 40 mg every other week from week 4 to week 8).

After induction with Exemptia, patients received maintenance azathioprine, and patients’ corticosteroids were tapered over a period of 2 to 3 months. Clinical response (a decrease in total Mayo score of at least 3 points or more than 30% from baseline, plus a decrease in rectal bleeding score by at least 1 point and an absolute rectal bleeding score of 0 or 1) and clinical remission (a total Mayo score of 2 points or less, with no individual score above 1 point) were determined at week 8.

At week 8, 7 patients (24.1%) showed a clinical response, and 1 patient (3.5%) had achieved clinical remission. The 8 responders were maintained on azathioprine. Among the 21 non-responding patients, 4 required colectomies, 1 patient died, and 1 patient was lost to follow-up.

Adverse events were noted in 4 patients: 2 patients had pulmonary tuberculosis, and 2 had tubercular pericardial effusion (1 of whom also had cardiac arrhythmia). Mild injection-site reactions occurred in 2 patients.

The authors conclude that Exemptia had only limited efficacy when used for induction of remission in patients with moderate to severe steroid-refractory UC. Furthermore, the authors note, “In developing countries such as India, where 40% of the population is exposed to tuberculosis (a majority of whom have latent tuberculosis), biologicals and biosimilars should be prescribed with caution.” Large, multi-center trials will be required to allow for a more robust examination of the role of the biosimilar adalimumab in the management of UC.

Reference

Midha V, Mahajan R, Mehta V, et al. Efficacy and safety of the adalimumab biosimilar Exemptia as induction therapy in moderate-to-severe ulcerative colitis. Intestinal Research. 2018;16:83-89. http://dx.doi.org/10.5217/ir.2018.16.1.83. Published January 30, 2018. Accessed February 13, 2018.