Post hoc comparison of the effectiveness of tocilizumab, rituximab, mycophenolate mofetil, and cyclophosphamide in patients with SSc-ILD from the EUSTAR database

Tocilizumab (TCZ), rituximab (RTX), mycophenolate mofetil (MMF), and cyclophosphamide (CYC) are the immunosuppressants (IS) most frequently used for systemic sclerosis-associated interstitial lung disease (SSc-ILD). This post hoc study aimed to compare their effectiveness in patients with SSc-ILD from the European Scleroderma Trials and Research (EUSTAR) database. We included radiologically confirmed SSc-ILD patients with treatment records for TCZ, RTX, MMF, or CYC. The primary endpoint was the change in forced vital capacity (FVC) percent predicted from baseline to follow-up. Analyses were adjusted for clinical and demographic characteristics, cotreatments, and follow-up duration using propensity score-based inverse probability of treatment weighting (IPTW). Nine hundred fifty-five patients with 997 treatment observations were included in the study. The median follow-up time was 11 months (IQR, 8-14 months). After IPTW, the changes in FVC percent predicted were not significantly different in the multigroup comparison (P = .101). Paired comparisons showed no significant difference. CYC was associated with stable FVC in logistic regression. For subgroup analysis, the treatment differences in change of FVC percent predicted among the 4 groups were not significant in patients with combination IS or previous exposure to TCZ, RTX, or conventional IS, as well as in current smokers or nonsmokers, and regardless of whether observations started either at the initiating or noninitiating stage of the treatment. In this first large real-world study, the effectiveness of TCZ, RTX, MMF, and CYC on FVC change in SSc-ILD patients was not statistically different.