Rituximab may prevent long-term comorbidities in treatment of pemphigus

Rituximab is associated with higher protection against long-term cardiovascular and metabolic diseases, but similar in survival rate, compared with other adjuvant agents in the treatment of pemphigus, according to a study.

“Pemphigus is a potentially life-threatening autoimmune bullous disease that manifests with erosions and blisters in the skin and mucosal surfaces,” Khalaf Kridin, MD, PhD, of the Lübeck Institute of Experimental Dermatology at University of Lübeck in Germany, and colleagues wrote. “Despite the substantial drop in the 1-year mortality rates of patients with pemphigus who receive proper treatment, they remain more susceptible to death compared with the general population.”

Systemic corticosteroids are the first-line therapy for this condition; however, due to highly adverse events, adjuvant agents such as azathioprine and mycophenolate mofetil (MMF) have been introduced to provide a favorable corticosteroid-sparing effect.

Rituximab, a monoclonal chimeric mouse/human antibody that targets CD20-expressing B lymphocytes, has demonstrated highly effective results as a treatment for moderate to severe pemphigus when used in conjunction with low-dose and short-term corticosteroids. Little is known, however, about the long-term complications of this treatment.

In their retrospective cohort study, Kridin and colleagues evaluated the long-term cardiovascular and metabolic comorbidities and mortality rates of patients with pemphigus treated with rituximab compared with azathioprine or MMF.

Researchers analyzed 1,602 patients treated with rituximab group (n = 801; mean age, 54.8 years; 52.2% women) or azathioprine/MMF (n = 801; mean age, 54.4 years; 54.6% women). Eligible patients underwent propensity score matching based on demographic variables and various comorbidities.

Results showed that rituximab-treated vs. azathioprine/MFF-treated patients experienced a lower risk of myocardial infarction (RR = 0.45; 95% CI, 0.24-0.86), stroke (RR = 0.42; 95% CI, 0.26-0.69) and peripheral vascular disease (RR = 0.47; 95% CI, 0.28-0.79). Those treated with rituximab also had a lower risk of hypertension (RR = 0.48; 95% CI, 0.38-0.63), hyperlipidemia (RR = 0.45; 95% CI, 0.32-0.64), type 2 diabetes (RR = 0.63; 95% CI, 0.51-0.77), obesity (RR = 0.49; 95% CI, 0.34-0.72) and osteoporosis (RR = 0.46; 95%CI, 0.30-0.71).

The risk of pulmonary embolism was comparable between groups (RR = 0.63; 95% CI, 0.33-1.19). Additionally, the risk of mortality was statistically similar between groups, with 37 deaths occurring in the rituximab group compared with 60 in the azathioprine/MFF group (HR = 0.94; 95% CI, 0.62-1.43).

“Rituximab was associated with significant protection against the development of several long-term cardiovascular and metabolic outcomes in pemphigus,” the researchers wrote. “The study results suggest that rituximab might be particularly preferred in individuals with cardiovascular and metabolic risk factors, for whom corticosteroid-related adverse events must be strictly avoided.”