baricitinib in the treatment of adults with alopecia areata

Last edited 08/2023 and last reviewed 10/2023

Baricitinib in the treatment of adults with alopecia areata

Alopecia areata (AA) is a nonscarring form of hair loss characterized by well-defined patches of alopecia, typically involving the scalp, and less commonly by near-complete or complete scalp and body hair loss (1)

• although the scalp is usually affected, the disease can involve any hair-bearing areas of the body
• approximately 2% of the global population suffers from AA
• in a mouse model of AA, up-regulation of interleukin-15 in hair follicles leads to recruitment and activation of natural killer gene 2D-expressing CD8 T cells, which, in turn, produce interferon-gamma, further activating the hair follicle epithelial cells (1)
  • cell signaling via interferon-gamma and interleukin-15 occurs via the Janus kinase (JAK) family of enzymes, and JAK inhibitors have been found to reverse disease (1)

Baricitinib in the treatment of adults with alopecia areata

• baricitinib is an oral JAK inhibitor with relative selectivity for JAK1 and JAK2 (2,3)
• in two phase 3 trials involving patients with severe alopecia areata, oral baricitinib was superior to placebo with respect to hair regrowth at 36 week (3)
  • acne, elevated levels of creatine kinase, and increased levels of low- and high-density lipoprotein cholesterol were more common with baricitinib than with placebo
• study by King et al showed that results that once-daily baricitinib is effective for patients with >= 50% scalp hair loss
  
  
• in a pooled analysis of 2 phase 3 randomized clinical trials, 25% of baricitinib, 2 mg, nonresponders who uptitrated to baricitinib, 4 mg, achieved at least 80% scalp coverage (Severity of Alopecia Tool score <=20) by week 76

Reference:

• Olamiju B, Friedmann A, King B. Treatment of severe alopecia areata with baricitinib. JAAD Case Rep. 2019 Oct 22;5(10):892-894.
• Jabbari A, Dai Z, Xing L, Cerise JE, Ramot Y, Berkun Y, Sanchez GA, Goldbach-Mansky R, Christiano AM, Clynes R, Zlotogorski A. Reversal of Alopecia Areata Following Treatment With the JAK1/2 Inhibitor Baricitinib. EBioMedicine. 2015 Feb 26;2(4):351-5.
• King B, Ohyama M, Kwon O, Zlotogorski A, Ko J, Mesinkovska NA, Hordinsky M, Dutronc Y, Wu WS, McCollam J, Chiasserini C, Yu G, Stanley S, Holzwarth K, DeLozier AM, Sinclair R; BRAVE-AA Investigators. Two Phase 3 Trials of Baricitinib for Alopecia Areata. N Engl J Med. 2022 May 5;386(18):1687-1699
• King B, Ko J, Forman S, Ohyama M, Mesinkovska N, Yu G, McCollam J, Gamalo M, Janes J, Edson-Heredia E, Holzwarth K, Dutronc Y. Efficacy and safety of the oral Janus kinase inhibitor baricitinib in the treatment of adults with alopecia areata: Phase 2 results from a randomized controlled study. J Am Acad Dermatol. 2021 Oct;85(4):847-853.
• Ko JM, Mayo TT, Bergfeld WF, et al. Clinical Outcomes for Uptitration of Baricitinib Therapy in Patients With Severe Alopecia Areata: A Pooled Analysis of the BRAVE-AA1 and BRAVE-AA2 Trials. JAMA Dermatol. Published online August 09, 2023. doi:10.1001/jamadermatol.2023.2581