Comparison of clinical efficacy and cost-effectiveness of rituximab infusion and intravenous dexamethasone pulse therapy in pemphigus vulgaris: an open prospective randomized controlled pilot study.

Background: Rituximab (Rtx) and dexamethasone pulse (DP) are the two most commonly used therapeutic regimens in pemphigus vulgaris (PV).

Objectives: To compare the clinical efficacy, side-effect profile, cost-effectiveness and changes in desmoglein (Dsg) levels in patients with PV treated with an Rtx biosimilar or DP.

Methods: This open-label prospective randomized controlled study (trial registration number CTRI/2020/04/032978) was conducted at the All India Institute for Medical Sciences in New Delhi, India, from November 2018 to September 2023. Fifty patients with active PV were randomized into two groups: an Rtx group and a DP group. Patients in both groups also received oral prednisolone in a tapering regimen with azathioprine or mycophenolate mofetil. Follow-up was conducted monthly until remission, then quarterly for at least a year or until relapse. Primary outcomes were remission rates and time to remission; secondary outcomes included relapse rates, adverse events and analysis of cost-effectiveness. Serum anti-Dsg titres were measured at baseline, remission and relapse.

Results: Disease control was achieved within a median of 1 month in 96% of patients in both groups. Remission rates were 92% in the Rtx group and 84% in the DP group, with a similar median time to remission of 3 months. Relapse after attaining remission occurred twice as frequently in the DP group (76% vs. 39%) after a median of 10.5 months. Serum anti-Dsg1 and anti-Dsg3 declined significantly at remission and rose again at relapse. Adverse events, including gastrointestinal and general disorders, were more common in the DP group. Cost analysis revealed Rtx was 20% more cost-effective than DP.

Conclusions: While both regimens were equally effective in inducing remission in patients with PV, Rtx offered superior long-term disease control, fewer relapses and adverse events, and greater cost-effectiveness.