Baricitinib for Folliculitis Decalvans: An Option for Refractory Disease

Baricitinib Reduced Disease Activity in Refractory Folliculitis Decalvans

In 2020, Authors from Australia reported the use of the JAK inhibitor tofacitinib in the treatment of refractory folliculitis decalvans. Now the same group provides us with evidence that the JAK inhibitor baricitinib may be an option too. Baricitinib exerts its effects by inhibiting JAK1 and JAK2 enzymes. Tofacitinib inhibitors JAK 1 and JAK 3 and to a lesser extent JAK 2.

The authors described four patients with refractory FD responding to baricitinib at 3.4 mg to 6. 8 mg daily. Response to treatment was assessed via patient-reported symptoms, physical examination and review of serial photography.

Case 1 was a 50-year-old Caucasian man with an 8-year history of recalcitrant FD affecting the vertex.

Case 2 was a 67-year-old Caucasian man with a 5-year his- tory of severe FD affecting the mid-scalp.

Case 3 was a 33-year-old Caucasian woman with a 17-year history of persistent FD affecting the vertex, nape of neck and frontal scalp.

Case 4 was a 32-year-old Caucasian woman with a 10-year history of treatment-resistant FD.

In these patients baricitinib was added to topical steroids, topical and oral antibiotics, minoxidil and other recognized treatments for FD. A reduction in symptoms was noted after 1-3 months. When doses were reduced in 2 of the 4 patients, a flare occurred.

Comment

Although we often think of folliculitis decalvans as being mediated by bacteria and especially the effects of Staphylococcus aureus, it’s clear that anti-lymphocytic and anti-inflammatory agents are very much a part of the treatment algorithm for folliculitis decalvans. Topical steroids, steroid injections, TNF inhibitors, apremilast are helpful in the tougher to treat diseases.

JAK inhibitors seem to be too.

The authors remind us in this report that non-specific activation of T lymphocytes by staphylococcal superantigens binding to major histocompatibility complex (MHC) class II proteins have been implicated in FD pathogenesis. The ability of JAK inhibitors to block or reduce this activation may be helpful in the disease.

REFERENCE

Moussa A et al. Successful treatment of folliculitis decalvans with baricitinib: A case series. Australas J Dermatol. 2022 Jan 22.

Jerien et al. Folliculitis decalvans responsive to tofacitinib: A case series. Dermatol Ther . 2020 Nov;33(6):e13968.