An assessment of treatment history and its association with clinical outcomes and relapse in 155 pemphigus patients with response to a single cycle of rituximab.

BACKGROUND: Studies of pemphigus vulgaris and foliaceus patients treated with rituximab have used several different dosing protocols. Likewise, patients' clinical history varies in the length of the disease prior to initiation of rituximab, previous immunosuppressants used and adjuvants used during rituximab treatment.
OBJECTIVE: We sought to assess clinical factors associated with improved outcomes and a greater duration from last dose of rituximab to time of relapse in patients responding to a single cycle of rituximab.
METHODS: We retrospectively evaluated published cases of pemphigus patients treated with a single cycle of rituximab.
RESULTS: One hundred and fifty-five patients were evaluated. An increased number of months with disease before receiving treatment were associated with failure to achieve complete remission. Patients treated using the low-dose rheumatoid arthritis protocol (2 × 500 mg) experienced a lower rate of complete response and a decrease in the time to relapse. Patients treated using the standard lymphoma protocol (375 mg/m(2) × 4 weeks) demonstrated improved time to relapse. There was no difference seen in the rate of patients reaching complete response in patients treated with the standard lymphoma protocol vs. the standard rheumatoid arthritis protocol (1000 mg × 2). The use of adjuvant plasma exchange or immunoadsorption was associated with an increase in the time to relapse.
CONCLUSION: Based on these observations, the low-dose rheumatoid arthritis protocol should not be recommended due to the inferior clinical response and shortened time to relapse.