INTRODUCTION

The increasing incidence of alopecia in its various clinical forms and its impact on the patient’s quality of life have highlighted the need for an effective and safer therapeutic option.

Particular interest has been shown in molecules that inhibit the JAK-STAT signaling pathway: JAK inhibitors. Their efficacy has been proven by numerous studies, yet the therapeutic response is person-dependent and, above all, unpredictable, with a significant suspensory effect.

Moreover, the use of JAK inhibitors is not without risk and may be subject to numerous side effects, hence the need to respect both the indications and contraindications of these molecules, as well as to perform rigorous clinical and biological monitoring.

CASE REPORT

We conducted a prospective study on 10 patients with different forms of alopecia treated with tofacitinib 11 mg/day for an average of thirteen months.

The average age was 31.5, ranging from 10 to 55 years, with a female predominance (60%, n = 6).

Herein, we describe ten cases of alopecia, including 5 universal, 4 decalvating, and 1 plaque, with two common denominators: failure to respond to any of the topical and systemic treatments for alopecia, notably inflitrations, bolus and minipulses of corticosteroid therapy, weekly treatment with methotrexate, and the significant psychological impact.

Dermoscopy of all patients revealed black and yellow spots, as well as several downy hairs in places. The therapeutic decision was to treat the patients with tofacitinib 11 mg/day after a pre-therapeutic workup, which proved normal in all patients.

Clinical evolution was marked by partial hair regrowth at 6 months in 90% of the patients and complete regrowth between 12 and 13 months in 80%, with only one case of no response to treatment (Figs. 1 – 3).

	Figure 1: Initial appearance of patient 1 (a), partial regrowth after 6 months of treatment (b), total regrowth at 13 months (c).
	Figure 2: Initial appearance of patient 2 (a), partial regrowth after 6 months of treatment (b), full regrowth at 13 months (c).
	Figure 3: Initial appearance of patient 3 (ab), full regrowth at 13 months (cd).

Long-term evolution showed three cases of relapse after three months of treatment discontinuation, with no side effects reported in any of the patients.

DISCUSSION

Alopecia is an autoimmune disease resulting from an attack on the hair follicle by autoreactive CD8 T cells [1]. Interleukin 15 (IL-15), which is secreted by hair follicles, activates CD8 T lymphocytes via JAK1 and 3, which promote the secretion of interferon-gamma, which by binding with hair follicles via JAK-1 and JAK-2, generates greater secretion of IL-15 responsible for a vicious circle.

It would, therefore, seem that JAK inhibitors agents could interrupt the pathogenesis of alopecia by acting on the hair follicle via JAK-1 and JAK-2, or by acting on T lymphocytes via JAK-1 and JAK-3 [2,3].

Among the JAK inhibitors most frequently used in the treatment of alopecia, that is, tofacitinib (JAK 1-2-3), baricitinib (JAK 1-2), and ruxolitinib (JAKS 1-3), topical forms are also available, notably, ruxolitinib cream 1.5% and tofacitinib cream 2% [4–6].

Treatment duration generally depends on the therapeutic response and individual tolerance, dosing varies according to the molecule. For ruxolitinib, the dose is 5–25 mg twice daily; for tofacitinib, the dose is 11 mg as a single dose or 5 mg twice a day; and for baricitinib, the dose is 4 mg/day [1,7].

Like all drugs, JAK inhibitors are not innocuous treatments, so it is essential to ask for a pre-treatment check-up to detect any contraindications, including a blood count, renal, liver, and lipid profiles, and serological tests.

JAK inhibitors are blamed for a multitude of side effects, including a higher incidence of common infections, notably upper respiratory tract infections, urinary tract infections, as well as an increased incidence of tuberculosis, shingles, and other opportunistic infections [8–10].

The risk of developing neoplasia, notably lymphoma and melanoma, has been incriminated by certain cohorts [11–13], there is also the possibility of developing toxidermia [1] or cardiovascular and thromboembolic diseases [1,14,15], as well as biological disturbances [1], hence the importance of conducting a check-up during the first month of treatment and then quarterly, including a CBC and liver, kidney, and lipid tests.

As with all immunosuppressive drugs, live attenuated vaccines are contraindicated; if they are necessary, they must be administered at least three weeks before the beginning of treatment, whereas all inactivated vaccines may be administered [1,16].

Although JAK inhibitors have been shown to be effective in treating alopecia [17], their suspensory effect on the discontinuation of treatment is significant, hence the importance of informing the patient before initiating treatment.

CONCLUSION

The efficacy of anti-JAKs in the treatment of alopecia has been proven by numerous studies, yet the short- and long-term evolution remains unpredictable and, above all, person-dependent.

REFERENCES

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