Strategy Reduces Relapse After Rituximab Rx for Pemphigus

TOPLINE:

A study of patients with pemphigus who were in remission after a rituximab cycle found that administering an additional infusion at month 6, when guided by relapse predictors, significantly improved remission.

METHODOLOGY:

• Researchers conducted a multicenter cohort study across France from September 2018 to June 2023, which included 87 adults (mean age, 55.3 years; 50.6% women) with newly diagnosed pemphigus vulgaris (73.6%) or pemphigus foliaceus (26.4%).
• Patients received infusions of rituximab on days 1 and 14, combined with short-term prednisone.
• Of the 77 patients who achieved complete remission (CR) at 6 months, 30 had at least one relapse predictor (Pemphigus Disease Area Index score ≥ 45, desmoglein 1 antibodies > 20 IU/mL, and/or desmoglein 3 antibodies > 130 IU/mL) and received an additional rituximab dose. Forty-seven patients without a relapse predictor did not receive any maintenance dose at month 6. The primary endpoint was the CR rate without corticosteroid therapy for 2 months or more at month 12 among those who had a CR after the first rituximab cycle and were treated on the basis of early relapse predictors. Secondary endpoints included the relapse rate over 12 months among those who had achieved a CR after the first cycle, the number needed to treat (NNT) with rituximab to avoid a relapse, and safety.

TAKEAWAY:

• None of the 30 patients with a relapse predictor who were retreated with a maintenance infusion at month 6 had relapsed at 12 months.
• Of the 47 patients who were in CR and had no relapse predictors at month 6, two relapsed between 6 and 12 months (for an overall 2.6% relapse rate among the 77 patients). At 12 months, one of the two patients was in CR, and the other relapsed shortly before 12 months.
• Among 77 patients with a CR at month 6, 98.7% achieved CR at month 12, and 93.5% achieved a CR without corticosteroid therapy for at least 2 months.
• Based on the overall relapse rate of 2.6% and the 17.6% relapse rate in the RITUX 3 trial, the NNT to avoid one relapse using the predictors was 3.6 (95% CI, 1.6-46.5). There were eight non-severe infusion-related adverse events and eight rituximab-related severe toxicities.

IN PRACTICE:

“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 authors wrote. The additional rituximab infusion at 6 months “according to these predictors would allow a significant reduction in the rate of short-term relapse in patients with moderate to severe pemphigus,” they added.

SOURCE:

The study was led by Vivien Hébert, MD, PhD, Department of Dermatology, Centre Hospitalier Universitaire de Rouen, Rouen, France. It was published online on February 5 in JAMA Dermatology.

LIMITATIONS:

The main limitation was the observational, noninterventional study design. Corticosteroid tapering guidelines were not followed in some patients.

DISCLOSURES:

The study was supported by the French Society of Dermatology. Hébert and another author disclosed receiving consulting fees from pharmaceutical companies outside this work. Other authors had no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.