In the European Union and Japan, baricitinib, a selective Janus kinase 1/Janus kinase 2 inhibitors, is approved for the treatment of moderate-to-severe atopic dermatitis (AD) in adults who are candidates for systemic therapy. The goal of this study was to assess the safety of baricitinib 2 mg in an Alzheimer’s disease clinical trial. Two databases were created to summarise six double-blind, randomised, placebo-controlled trials and two long-term extension studies. Six 16-week trials with baricitinib 2 mg were used to compare it to a placebo. Patients who received baricitinib 2 mg at any point during the eight investigations were included in the All-bari-2-mg-AD study. In all, 1598 patients were given twice-daily baricitinib 2 mg for 1434.2 patient years. Treatment-emergent adverse events were more common with baricitinib 2 mg compared to placebo. Major adverse events, serious infections, and opportunistic infections were uncommon and comparable between baricitinib 2 mg and placebo. Herpes simplex rates were increased with baricitinib 2 mg vs placebo; rates were reduced with prolonged 2 mg administration. Other than non-melanoma skin cancer, there were five malignancies, two severe adverse cardiovascular events, one peripheral venous thrombosis, one arterial thrombosis, and no pulmonary embolisms, deep vein thromboses, or fatalities in All-bari-2-mg-AD.

This comprehensive study of baricitinib 2 mg in individuals with moderate-to-severe Alzheimer’s disease supports the drug’s well-established safety profile. To assess the risks of malignancies and severe adverse cardiovascular events, patients must be exposed to therapy for a longer period of time.