Efficacy and safety of tocilizumab in elderly patients with rheumatoid arthritis

Objective: To assess the safety and efficacy of tocilizumab (TCZ) in elderly (≥65 years) rheumatoid arthritis (RA) patients treated in daily practice.

Methods: We conducted a retrospective study of TCZ use in RA patients in five French university hospitals between 2009 and 2012. We considered two age groups, under 65 years (<65) and over 65 years (≥65). TCZ efficacy was evaluated at 24 weeks by the European League Against Rheumatism (EULAR) response and remission score. We also evaluated drug maintenance and safety, relative to adverse events discontinuation. A multivariate cumulative logit model for ordinal categories was performed to assess the relationship between age class and EULAR response (none, moderate and good) adjusted on possible confounders. TCZ retention (drug survival) over time was estimated with the Kaplan-Meier method. Treatment retention curves were compared according to age group with the log-rank test.

Results: Among 222 RA patients treated with TCZ, 61 (27.5%) were≥65 years at the initiation of treatment. After 6 months, this elderly patient group less often reached remission (27.8% versus 45.6%; P=0.02) or good EULAR response (40.7% versus 61.0%; P<0.01) compared to the younger patient group (<65). Multivariate analysis adjusted on baseline C-reactive protein and disease duration confirmed that elderly patients were more likely to have a lower EULAR response (none vs moderate-good or none-moderate vs good) (OR: 3.63; 95% CI [1.86-7.06], P<0.001) compared to younger patients. Drug maintenance for TCZ and adverse events discontinuation rates were similar between the two age groups.

Conclusion: In daily practice, TCZ seems to be well tolerated in RA patients but is less efficient in elderly patients. A broader field of analysis to include an international register will be required to confirm these results.