What is your approach to tapering off rituximab in a patient with pemphigus who seems to be remission?

When evaluating a patient in clinical remission, I think the decision to taper should be weighed in light of multiple variables, including the patient’s duration and severity of disease prior to remission, extent of previously failed therapies, tolerability of rituximab, and anti-desmoglein antibody levels. While the RITUX 3 trial established the FDA-approved regimen of a decreased dose of rituximab (500 mg at 12 months) after an initial 2 g dose, my preference is to space out dosages with close clinical and serologic monitoring and a low threshold to repeat Rituximab if/when appropriate.

When a patient has achieved clinical remission and also has low-titer antibodies to desmoglein 1 and 3 (with the exception of patients who may have non-pathogenic antibodies, which can be trended over time), we discuss tapering rituximab. There are, of course, pemphigus patients, especially those with moderate disease who may respond to one round of rituximab and never require another dose, so this tapering recommendation is for patients who have been on therapy for more than one cycle. In severe patients, I often recommend doing the 2nd round of rituximab at the 6 month mark, especially if they had initially high-titer antibodies, and this is an active area of research. When I do taper rituximab, I spread out the interval first to ensure a...