Review of Baricitinib in the Treatment of Alopecia Areata.

Alopecia areata (AA) is a debilitating autoimmune disease that results in non-scarring hair loss. Baricitinib is the Food and Drug Administration (FDA) approved treatment for AA.  Objective: Review the mechanism of action, pharmacokinetics, pharmacodynamics, efficacy, and safety of baricitinib in the treatment of AA.  Methods: A literature review was conducted using the MEDLINE (PubMed) and EMBASE databases for articles published between January 2010 to November 2022. Articles in English discussing baricitinib's efficacy and safety in AA, pharmacodynamic, and pharmacokinetic profiles were included.Two identical phase III trials (BRAVE-AA1 and BRAVE-AA2) were evaluated. A greater percentage of subjects receiving baricitinib 4 mg or 2 mg dose achieved a Severity of Alopecia Tool score equal to or less than 20 vs placebo. In BRAVE-AA1, for 4 mg, 2 mg, and placebo, respectively, these values were 38.8%, 22.8%, and 6.2%; in BRAVE-AA2, these values were 35.9%, 19.4%, and 3.3% (P<0.001).Baricitinib is the first FDA-approved treatment for AA. Other treatments for AA are used off-label with variable efficacy. Baricitinib is associated with black-box warnings due to adverse effects (AEs) associated with other Janus Kinase (JAK) inhibitors or use in other diseases. In the two large AA trials, AEs were considered mild or moderate; those reported more often with baricitinib than placebo included acne, elevations of low- and high-density lipoprotein cholesterol, and elevation of creatinine kinase. Baricitinib is a relatively tolerable and safe therapeutic alternative for severe AA, although additional study is needed to assess its long-term efficacy and safety.  Citation: Singh R, Driscoll MS. Review of baricitinib in the treatment of alopecia areata. J Drugs Dermatol. 2023;22(9):935-939. doi:10.36849/JDD.7357.