A French multicenter cohort study found that using predictive factors to guide additional rituximab treatment may significantly reduce early relapse rates in patients with pemphigus from 17.6% to 2.6% in the first year.
In the study, published in JAMA Dermatology, researchers evaluated 87 patients with newly diagnosed pemphigus who received rituximab between September 2018 and June 2023. The study assessed whether providing an additional rituximab infusion at 6 months in patients with specific relapse predictors could prevent disease recurrence.
"This ... study indicates that using predictors such as baseline [Pemphigus Disease Area Index] (PDAI) score, anti–[desmoglein-1] (DSG1) antibodies, and/or anti–[desmoglein-3] (DSG3) antibodies to initiate preemptive treatment with additional rituximab may reduce the rate of short-term relapse," wrote Vivien Hébert, MD, PhD, of the Department of Dermatology at Centre Hospitalier Universitaire de Rouen, and colleagues.
The researchers identified three key predictors of relapse: a baseline PDAI score ≥ 45, DSG1 antibodies > 20 IU/mL, and/or DSG3 antibodies > 130 IU/mL at 3 months.
Among 77 patients who achieved complete remission at 6 months, 39.0% (n = 30) of them had at least one predictor and received additional rituximab (500 or 1,000 mg). The remaining 47 patients without predictors did not receive additional treatment.
The strategy proved effective, since 0% of the 30 patients with predictors who received additional rituximab relapsed. Only two patients without predictors experienced relapse, resulting in an overall relapse rate of 2.6% compared with the historical relapse rate of 17.6% from previous studies.
Safety data showed eight serious adverse effects among five patients, with no reported deaths. The most common adverse events included infusion-related reactions such as hyperthermia and hypotension.
"The findings of this cohort study validate the use of predictors of early relapse after an initial cycle of rituximab in patients with pemphigus," the study authors concluded.
The researchers noted that a randomized clinical trial (ClinicalTrials.gov identifier NCT05898308) is currently underway to further test this strategy.
The study was supported by a grant from the French Society of Dermatology.
Full disclosures can be found in the study.
