The Use of Janus Kinase Inhibitors for Lichen Planus: An Evidence-Based Review

Background Lichen Planus (LP) is a dermatological disorder characterized by violaceous papules that affect the cutaneous region, nails, scalp, and mucous membranes. Current molecular and clinical studies point to the Janus Kinase-signal transducer and activator of transcription (JAK-STAT) pathway as a potential effector of LP pathology. Objective This systematic review summarizes the current reported literature outcomes for patients receiving JAK inhibitors to treat LP. Methods MEDLINE and Embase were searched on 16 October, 2022, and 15 original articles were included, with 56 LP patients. Results (mean age: 54.5 years, range: 26-81 years, male: 26.8%). The treatment outcomes were included for the following JAK inhibitors: tofacitinib (n = 30), baricitinib (n = 16), ruxolitinib (n = 12), and upadacitinib (n = 2). Patient outcomes were classified into complete resolution, partial resolution, and no resolution. Patients achieving complete resolution represented 25% (n = 4/16) in the baricitinib group, 10% (n = 3/30) in the tofacitinib group, 16.7% (n = 2/12) in the ruxolitinib group, and 100% (2/2) in the upadacitinib group. Partial resolution patients represented 31.3% (n = 5/16) of baricitinib patients, 60% (n = 18/30) of tofacitinib patients, and 83% (n = 10/12) of ruxolitinib patients. 43.8% (n = 7/16) of baricitinib patients and 10% (n = 9/30) of tofacitinib patients had no resolution of lesions. Conclusion This review also highlights the significance of utilizing a uniform outcome measure for LP, as it aids in reporting more generalizable results, reduces reporting bias, and ultimately lead to improved clinical outcomes for LP patients.