Promising results of rituximab in systemic sclerosis

The largest routine care study of rituximab use in systemic sclerosis (SSc) patients showed significant changes in skin fibrosis but not in lung fibrosis.

The safety profile of the monoclonal antibody was considered good

The largest study of use in the routine care of rituximab in patients with systemic sclerosis (SSc) showed significant changes in skin fibrosis but not in lung fibrosis. Future studies are warranted into the possible role of rituximab in this patient population.

According to Yannick Allanore (Paris Descartes University, Paris, France), a few small-sized observational studies have suggested that rituximab might be a promising treatment in patients suffering from SSc. He and his team aimed to evaluate the outcomes of SSc patients receiving rituximab in routine care. This was done as a retrospective, longitudinal, multicentre, observational study in which eligible SSc patients were treated with rituximab upon the decision of their physician within the framework of European Scleroderma Trials and Research group (EUSTAR). This international scleroderma research network aims to foster the awareness, understanding, and research on systemic sclerosis and its management throughout Europe and the rest of the world. EUSTAR has a multicentre online database that allows following prospectively more than 15,000 patients with scleroderma in more than 200 international centers (1). 

“We determined epidemiological and clinical characteristics, the indication for initiating the treatment, as well as parameters at baseline and at the last visit under treatment,” Allanore explained. These parameters included the modified Rodnan Skin Score (mRSS), joint, lung and gastrointestinal involvements, treatment, laboratory tests and safety events. A total of 254 patients were included. Sixty-five percent of patients had diffuse cutaneous SSc, 54% was positive for anti-topoisomerase, and 71% had lung fibrosis. The indication for the treatment with rituximab was lung involvement in 56% of cases, followed by articular (42%) and skin involvements (30%). Mean follow-up was 2.5 years.

For Allanore: “A decrease was seen in patients with skin fibrosis and baseline mRSS ≥10 from 21.7 at baseline to 13.6 at the last visit (P<0.0001). In patients with lung fibrosis, forced vital capacity (FVC) at baseline was 74.4 and at last visit 76.1; for diffusing capacity or transfer factor of the lung for carbon monoxide this was 52.7 at baseline and 53.0 at the last visit.” In the whole population, 45 patients were able to stop the use of steroids and mean dose decreased from 10 mg to 7 mg in the other. Adverse events (AEs) were seen during the follow-up in 31% of patients of which 14% (n=35) had severe AEs. Of the patients experiencing SAEs, 9/35 had infections, 9/35 patients had cardiovascular events, 6/35 died (of which 2 deaths were possibly related to rituximab), 5/35 developed cancer, 4/35 had allergic reactions, 1/35 had agranulocytosis and 1/35 had SRC. A total of 9.4% of patients discontinued the treatment. “These results need to be confirmed by future randomized, controlled studies,” Allanore emphasized (2).

1. European Scleroderma Trials and Research group (EUSTAR). 
2. Allanore Y. Rituximab in systemic sclerosis: safety and efficacy data from the EUSTAR network. Abstract OP0142. EULAR 2018.