who do not respond to rituximab alone, results of a case series suggest.
Bullous pemphigoid (BP) is a rare, chronic, inflammatory, blistering disease that mainly occurs in people in their 50s through their 70s. BP has high morbidity and mortality, especially in people with comorbidities common to the elderly, yet no Food and Drug Administration–approved therapies for BP exist, Stephanie T. Le, MD, a dermatologist in the department of dermatology of the University of California, Davis, told this publication.
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Dr. Stephanie T. Le
“BP is typically thought of as an IgG-mediated disease, but many BP patients also have elevated levels of total circulating IgE levels, which has been linked to hallmarks of bullous pemphigoid, including blisters,” Dr. Le said. “These findings suggest that ideal BP treatments, such as rituximab and omalizumab, should target both IgG and IgE.”
In a study published in JAMA Dermatology, Dr. Le and her coauthors analyzed the electronic medical record data of adult patients with BP who were treated with combined rituximab and omalizumab at UC Davis between 2015 and 2022. The 10 patients who met their selection criteria averaged 62 years of age. Most were female, and most were non-Hispanic White. All had severe BP, with an initial mean BP Disease Area index score of 170, and all applied whole-body topical corticosteroid for treatment.
All participants received 1000 mg intravenous rituximab on days 0 and 15. In addition to rituximab, seven patients received subcutaneous high-dose omalizumab (300 mg every 2 weeks); and three patients received low-dose omalizumab (300 mg every 4 weeks or 150 mg every 2 weeks).
After a mean of 2.1 months, all patients in the high-dose omalizumab-plus-rituximab group had achieved complete remission. By contrast, all patients in the low-dose omalizumab-plus-rituximab group improved after a mean of 13 months, and none achieved complete remission.
At 3 months, all study participants were rated as being very much improved. All four patients in the high-dose omalizumab group who tapered omalizumab dosage or frequency had flare-ups within 1-3 months that resolved when they restarted the medication. Among patients who achieved complete remission, 4 of 7 required rituximab redosing between 6 and 16 months later. Rituximab alone did not achieve remission: Three patients needed to add high-dose omalizumab. All reported adverse effects were mild.
Alternatives to Corticosteroids Are Needed
For BP, “with no FDA-approved therapies available, corticosteroids remain first line for acute flares. However, prolonged corticosteroid use is associated with multiple adverse effects, including increased susceptibility to infection, osteoporosis, and diabetes mellitus,” Dr. Le pointed out. “Patients with BP who are treated with high-dose corticosteroids have significantly increased mortality and have very poor 1-year survival.
“Rituximab and omalizumab dual therapy offers another potential treatment option for severe or treatment-refractory BP,” she added. “We are hopeful that other physicians will adopt this therapy.”
The authors acknowledged limitations of the study, including its retrospective design, small sample size, lack of standardized intervals between rituximab and omalizumab, and variation in concurrent therapies, and they recommended further related research.
No conflicts of interest were reported. No funding details were provided.