Successful experience of rituximab therapy for systemic sclerosis-associated interstitial lung disease with concomitant systemic lupus erythematosus

Previous studies have demonstrated that B cells play critical roles in autoimmune disorders including systemic sclerosis (SSc) and systemic lupus erythematosus (SLE). However, the effectiveness of rituximab (RTX), a chimeric anti-CD20 antibody, for SSc-associated interstitial lung disease (ILD) or SLE disease activity remains controversial. We herein report an SSc patient with severely progressed ILD and concomitant SLE treated by two cycles of RTX at baseline and half a year later. This treatment improved ILD and SLE activities, along with reduction of dermal sclerosis and serum anti-topoisomerase I antibody levels. In addition, our detailed time-course data indicate that half a year may be appropriate as an interval between each cycle of RTX therapy aimed at SSc-associated ILD or SLE. Overall, the current report could pave the way to establish RTX as a disease-modifying drug for patients with SSc and/or SLE showing resistance to other already approved medications.