The following is a summary of “Long-term survival of subcutaneous biosimilar tumor necrosis factor inhibitors compared to originators: Results from a multicenter prospective registry,” published in the September issue of Rheumatology by Martinez-Vidal et al.

Researchers conducted a retrospective study analyzing the efficacy of biosimilar tumor necrosis factor (TNF) inhibitors to their original counterparts in the long-term survival of patients with rheumatic diseases and identifying factors that lead to drug discontinuation. 

They conducted a retrospective analysis of the BIOBADASER registry, including patients who began etanercept (ETN) or adalimumab (ADA) between January 2016 and October 2023. Survival probabilities were compared using Kaplan-Meier curves, and hazard ratios (HR) for drug discontinuation causes were estimated with Cox regression models.

The results showed that out of 4,162 patients, 4,723 treatment courses were analyzed (2991 ADA, 1732 ETN), with 722 using originators and 4,001 (84.71%) using biosimilars. Originators had higher discontinuation rates (53.32%) than biosimilars (33.37%). Inefficacy was the main reason for discontinuation (60.35%). Biosimilars had a lower risk of overall discontinuation (adjusted HR 0.84, 95% CI 0.75-0.95). Female sex, obesity, and second or later treatment lines increased discontinuation risk, while longer disease duration and methotrexate use were linked to better survival. No significant retention rate differences were found between biosimilars and originators when excluding nonmedical switching.

When considering inefficacy or adverse events, investigators concluded no significant differences in long-term survival between biosimilars and originators.

Source: jrheum.org/content/51/9/877