Two-year results of an open pilot study of a 2-treatment course with rituximab in patients with early systemic sclerosis with diffuse skin involvement.

OBJECTIVE

To study safety and potential efficacy of a 2-treatment course (month 0/6) with rituximab (RTX) in early diffuse systemic sclerosis (dcSSc).

METHODS

Two years' followup (open-label study) was done of 8 patients with early dcSSc. Patients received an infusion of 1000 mg RTX 2 times at months 0 and 6, with 100 mg methylprednisolone. Clinical measurements, Disease Activity Score, functional status, and CD19+ peripheral blood count were performed at months 0, 3, 6, 12, 15, 18, and 24 and histopathological evaluation of the skin at months 0, 3, 12, and 24.

RESULTS

There was a clinically significant change in skin score, with a mean Modified Rodnan skin score of 24.8 at baseline (SD 3.4) and 13.6 at Month 24 [SD 5.6; mixed models analyses (MMA) p < 0.0001] and a significant decrease in Disease Activity Score (DAS), with a median of 4.5 at baseline (range 1.5-7.5) and 0.5 at Month 24 (range 0.0-5.5; MMA p < 0.0001). Indices of internal organ involvement remained stable throughout the study. RTX induced effective B cell depletion at baseline and Month 6 (< 5 CD19+ cells/μl blood). The blindly assessed hyalinized collagen score changed significantly over time (MMA p = 0.009), with a mean of 69.3 at baseline (SD 22.8) and 33.1 at 24 months (SD 27.0). Five serious adverse events were considered unrelated to the RTX treatment.

CONCLUSION

A 2-treatment course (months 0/6) with RTX appears to be well tolerated and may have potential efficacy for skin disease and stabilization of internal organ status in early dcSSc. Clinical Trials Registration NCT00379431.