Biosimilar Safe, Effective for Noninfectious Uveitis

Adalimumab biosimilar SB5 is a safe and effective noninfectious uveitis therapy that drastically reduces uveitis relapse and retinal vasculitis incidence, according to research published in the Asia-Pacific Journal of Ophthalmology. 

The recent influx in approved adalimumab biosimilar products in Europe has raised concerns regarding potential immunogenicity, safety issues, loss of efficacy, and antidrug antibody development. While SB5 (Imraldi®, Biogen) has demonstrated equivalent clinical efficacy and safety in rheumatoid arthritis, data regarding the efficacy on noninfectious uveitis in both biologic-naïve and patients switching from the originator drug remain limited. 

To remedy this, researchers conducted a retrospective review of charts of patients with noninfectious uveitis treated with SB5 between 2018 and 2020. The primary study objective was SB5 efficacy in terms of uveitic relapse; secondary objectives included resolution of retinal vasculitis, SB5 impact on visual acuity, influence on daily glucocorticoid intake, overall survival in the cohort, and ocular complications and safety profile. 

The cohort included 47 eyes from 26 patients treated with SB5 (15 women). Median treatment duration was 16.50±6.00 months (range, 14 months). Five uveitis cases were unilateral and 21 were bilateral, with anterior, posterior, and panuveitis in 12, 10, and 25 eyes, respectively. Twenty-two patients in the cohort began biologic treatment due to active uveitis, while the 4 remaining patients were treated with SB5 due to uncontrolled systemic disease. 

Uveitis relapses decreased from 121 relapses per 100 patients per year in the 12 months prior to SB5 initiation to 4 relapses per 100 patients per year during the first 12 months of treatment, and from 115 relapses per 100 patients per year to 3 relapses per 100 patients per year at the time of the last follow-up. At the final follow-up, uveitis was inactive in 46 of 47 eyes. 

During the study period, the number of eyes affected by active retinal vasculitis also significantly decreased, with a post-hoc analysis showing a significant decrease from baseline to 3 months and baseline to 12 months. Only 1 patient showed no retinal vasculitis resolution at the end of the study period. Six eyes had UME at baseline, compared with no eyes at the final follow-up. 

Mean best-corrected visual acuity (BCVA) increased from 7.7±3.41 to 8.9±2.46 at baseline to follow-up. Mean glucocorticoid daily dose also decreased from baseline to follow-up (18.33±10.33 mg vs 5.75±2.29 mg) — a statistically significant difference. 

At the conclusion of the study, 2 patients had discontinued SB5 therapy: 1 due to prostatic carcinoma diagnosed after 6 months of biologic therapy and 1 due to a loss of efficacy. A mild injection site reaction was noted in 1 patient. 

Estimated cumulative SB5 retention rate was 91.8% at 12- and 20-month follow-up visits, and no new ocular complications emerged during the course of treatment. 

“SB5 biosimilar is effective for the treatment of [noninfectious uveitis], either idiopathic or associated with systemic inflammatory diseases, by controlling uveitis relapses, drastically reducing the occurrence of retinal vasculitis, and improving visual acuity,” according to researchers. “Moreover, SB5 shows an excellent drug retention rate with a significant [glucocorticoid]-sparing effect.”

“In this context, SB5 biosimilar may be a reliable additional weapon in the growing therapeutic armamentarium available for [noninfectious uveitis],” they report. 

Reference

Sota J, Gentileschi S, Vitale A, et al. Effectiveness of SB5, an adalimumab biosimilar, in patients with noninfectious uveitis: A real-life monocentric experience. Asia Pac J Ophthalmol. Published online March 19, 2021. doi:10.1097/APO.0000000000000380