Clinical and immunological outcomes of high- and low-dose rituximab treatments in patients with pemphigus: a randomized, comparative, observer-blinded study.

BACKGROUND

Rituximab is a promising therapy in pemphigus. However, there is no consensus on optimum dose.

OBJECTIVES

To compare the efficacy, in terms of clinical and immunological outcomes in patients with pemphigus, of a high (2 × 1000 mg) vs. a low dose (2 × 500 mg) of rituximab.

METHODS

This was a randomized, observer-blinded trial wherein 22 patients with pemphigus were randomized into two treatment groups. Patients received either two doses (day 0 and day 15) of 1000 mg rituximab or 500 mg rituximab, and were followed up for 48 weeks. Clinical activity was assessed by a blinded investigator. Indices of enzyme-linked immunosorbent assays (ELISAs) for desmoglein (Dsg)1 and Dsg3, and CD19 cell count were examined at regular intervals.

RESULTS

There was no statistically significant difference in early and late clinical end points, and total cumulative dose of corticosteroids between the two groups. At week 40, the fall in Ikeda severity score was significantly more in the 2 × 1000 mg group than in 2 × 500 mg group (P = 0·049). Patients in the 2 × 500 mg group received a significantly higher cumulative dose of azathioprine (P = 0·018). The ELISA indices of Dsg1 and Dsg3 showed a statistically significant decline in the 2 × 1000 mg group only. B cell repopulation occurred earlier in the 2 × 500 mg group by 8 weeks.

CONCLUSIONS

A few clinical and immunological study parameters have suggested improved outcomes in patients receiving high-dose (2 × 1000 mg) rituximab.