Treatment with rituximab is associated with significantly improved cutaneous sclerosis: real-world observations in an Indian cohort.

BACKGROUND

Rituximab is effective in both systemic sclerosis (SSc)-associated interstitial lung disease (ILD) and cutaneous sclerosis. However, most studies report improvement in skin sclerosis as a secondary outcome, leaving a gap in the literature on rituximab's dermatological impact.

OBJECTIVES

To evaluate rituximab's effectiveness in reducing skin sclerosis.

METHODS

This retrospective study was conducted at a tertiary care centre in northern India. Records of patients with SSc from 2016 to 2023 were reviewed. Clinical assessments, investigations and standard treatment for end-organ damage were undertaken according to clinical presentation and the European Alliance of Associations for Rheumatology guidelines. Rituximab was administered in two doses of 1 g each, administered 2 weeks apart to patients with a baseline modified Rodnan skin score (mRSS) of ≥ 14 with or without ILD or a baseline mRSS of ≥ 7 and < 14 in the presence of ILD, as per a departmental protocol. Patients were divided into two groups: those receiving rituximab (the rituximab group) and patients who were not treated with rituximab (the non-rituximab group). Treatment response was evaluated based on change in mRSS and overall survival.

RESULTS

Among 98 patients with SSc, 37 received rituximab and 61 were in the non-rituximab group. The rituximab group had a higher percentage of patients with diffuse skin sclerosis (DSS) [70% (26/37) vs. 30% (18/61)] and a higher mean baseline mRSS [20.1 (SD 9.4) vs. 11.5 (SD 8.0)]. There was a significantly greater mean percentage reduction in mRSS [47.9% (SD 27.4) vs. 31.2% (SD 31.4), P = 0.01] in the rituximab group compared with the non-rituximab group. Overall survival (Kaplan-Meier curve analysis) was 66% at 140 months in the rituximab group compared with 53% at 95 months in the non-rituximab group (P = 0.85). Patients with limited skin sclerosis (LSS) had better survival (78% at 100 months) compared with those with DSS (47% at 140 months, P = 0.05). On binomial logistic regression analysis, a greater percentage reduction in mRSS was the strongest predictor of survival (P = 0.04).

CONCLUSIONS

Rituximab treatment resulted in a significant reduction in skin sclerosis even in patients with more severe baseline skin sclerosis, although it did not demonstrate any survival benefit.