Intralesional Rituximab in the Treatment of Refractory Oral Pemphigus Vulgaris.

IMPORTANCE Oral lesions of pemphigus vulgaris are usually recalcitrant and respond slowly to treatments. Corticosteroid injection is considered to be the most effective local treatment in oral pemphigus vulgaris. However, intralesional corticosteroids are not effective in all remnant lesions. In 3 such patients with pemphigus vulgaris, we evaluated the utility of 2 injections (on days 1 and 15) of intralesional rituximab, 5 mg/cm², in terms of accelerated healing, limitation of the use of systemic immunosuppressants, and reduction of their adverse effects. OBSERVATIONS Three patients (1 man and 2 women) received 2 doses of intralesional rituximab in March and April 2013. All 3 patients responded to the treatment. In patients 1 and 2, the objective severity score was reduced to 0 at the final visit from a baseline score of 4 and 5, respectively (range, 0-11). The subject severity score in these patients was reduced to 1.0 and 0 from a baseline score of 22.0 and 22.5, respectively. After clinical remission was achieved, patient 3 developed a relapse of mucosal lesions. At the final visit, all of the patients were satisfied with the treatment, with a mean satisfaction score of 8 (maximum score, 10). We found a marked decline in the CD19 cell count from a pretreatment mean count of 287 cells/µL to 6 cells/µL on day 15 after a single intralesional rituximab injection. Adverse events were limited to local pain in 1 patient. CONCLUSIONS AND RELEVANCE Intralesional rituximab administration lacks the adverse effects of intravenous administration. This method reduces the amount of drug administered and therefore is less expensive. Encouraging results from our study should prompt further evaluation of this novel route of rituximab administration in patients with refractory oral pemphigus vulgaris.