Baricitinib as a novel treatment for bullous pemphigoid: a case series report (preprint)

ABSTRACT

Bullous pemphigoid (BP) is an autoimmune blistering disorder occurring mostly in the elderly. The standard treatment of BP patients with systemic corticosteroid have some potential serious side effects. Up till now, there is still lack of novel treatment for BP patients. Baricitinib, a selective Janus kinase (JAK) 1 and 2 inhibitor, has been used to treat rheumatoid arthritis, alopecia areata, and COVID-19. Successful treatment of refractory BP by JAK inhibitors has been reported in sporadic cases. In this study, we reported 8 BP patients treated with baricitinib. The patients after treatment were followed up for 3-24 months, with an average of 9.1 months. All 8 cases achieved disease control and the mean disease control period was 3 weeks (1-6 weeks). The bullous pemphigoid disease area index total (21.2 ± 13.0 to 2.5 ± 4.3, p<0.01), erosion/blister (6.0 ± 7.7 to 0.2 ± 0.5, p<0.05), urticaria/erythema (10.2 ± 11.9 to 0.0 ± 0.0, p=0.06), mucosal erosion/blister (10.0 ± 6.4 to 4.5 ± 5.1, n=4, p=0.25) and itching NRS (3.6 ± 3.5 to 0.0 ± 0.0, p=0.06) scores were all reduced after 2 months’ treatment. Seven of 8 patients achieved complete remission during tapering at month 3 and did not experience relapse during the follow-up period. The serum levels of anti-BP180 autoantibodies (IgG) were reduced significantly (77.1 ± 47.8U/mL to 40.1 ± 37.1U/mL, n=6, p<0.05) after 3 months’ treatment. During the follow-up period, only one patient experienced mild elevation of serum creatinine level after 3 months’ treatment of baricitinib, which returned to normal through discontinuation of the medication. In conclusion, this study demonstrated that low-dose, short-term administration of baricitinib is effective and safe for treating BP patients.