Can we predict if patients with SLE will require more than one cycle of rituximab?

To identify clinical and serological features that distinguish patients with SLE who require single as opposed to repeated rituximab (RTX) cycles.

All 175 SLE patients followed up at University College Hospital from 2000 onwards were retrospectively reviewed. They were divided into a one-RTX-cycle group and a multiple-cycle group (2 or more cycles). Patients included had a follow-up of at least 3 years after their first RTX cycle, unless they needed a second infusion sooner.

A total of 131 patients were included; 44 (33.6%) received one cycle of RTX and 87 (66.4%) received two or more. The former were older at diagnosis (31.4 vs 21 years, P < 0.001) and at first RTX infusion (39.9 vs 29 years, P < 0.001). This group of patients had more organs/systems involved (P = 0.044), more leukopenia, lymphopenia and thrombocytopenia (P = 0.001, P < 0.0001 and P = 0.003, respectively) and lower C3 levels (P = 0.035). They also had fewer immunosuppressive drugs before RTX therapy compared with those who required multiple RTX cycles (P = 0.003). There was no statistical difference in either the clinical or serological response after the first RTX cycle between both groups. Furthermore, patients who had received more immunosuppressive treatments were more likely to require more than one cycle of RTX infusions (P = 0.007).

RTX is an effective option for SLE patients with severe flares. Patients who received more immunosuppressive drugs were more likely to receive more than one set of RTX infusions. This suggests that RTX is best used for SLE patients with no history of refractory disease.