JAK inhibitors for alopecia areata: a systematic review and meta-analysis

Research trends in alopecia areata: a cross-sectional bibliometric analysis of the top cited studies

In the field of alopecia areata research, various focuses including risk factors, epidemiology, molecular pathways, and treatment were constantly improving. However, to date, a bibliometric analysis summarizing the research trend is not available to date. The main objective of this study was to provide researchers with an overview of the research trend on alopecia areata in the past two decades. In Web of Science database, screening and extraction of studies related to alopecia areata has been performed. Within studies related to alopecia areata, the most cited 100 studies were appraised and the information of articles, including the citation amounts, keywords and publication types, was extracted for analyses. On average, each study in the top 100 list was cited 104.72 times. Within the top 100 list, the most focused fields were on the management of alopecia areata (34%), molecular mechanisms (28%) and epidemiological issues (23%). Approximately one third of the management-associated studies focused on Janus kinase (JAK) inhibitors (10 studies) and 5 studies focused on the efficacy of corticosteroids for alopecia areata. According to the results of the keyword analysis, JAK inhibitors had become the most mentioned keywords in the field of alopecia areata research since 2016. The top 100 most referenced papers in the field of alopecia areata mostly focused on essential aspects such as treatment options, pathogenesis, risk factors, and comorbidities. The results of the current study could be considered a potential resource for future research and patient care information.

Novel investigational drugs for alopecia areata and future perspectives

INTRODUCTION

Alopecia areata (AA) is an immune-mediated disease that causes non-scarring hair loss. While acute, solitary patches often spontaneously remit, developing secondary patches or failure of the disease to resolve within 6-12 months predicts a poor prognosis, with an increased risk of alopecia totalis or universalis. Chronic AA increases the risk of depression and suicidality and reduces quality of life. Treatment options for chronic or acute diffuse AA were previously limited to corticosteroids and traditional immunomodulators. Two Janus Kinase (JAK) inhibitors are now approved for the treatment of chronic AA.

AREAS COVERED

The results of landmark phase 3 trials for three JAK inhibitors, baricitinib, ritlecitinib, and deuruxolitinib are discussed. Evidence for other JAK inhibitors, biologics, and phosphodiesterase-4 inhibitors are also presented. Therapies currently undergoing clinical trials are listed.

EXPERT OPINION

JAK inhibitors are a safe and efficacious treatment of moderate-to-severe AA. Early intervention, regardless of severity, allows for improved treatment efficacy. It is uncertain how long patients should remain on JAK inhibitors; discontinuation often leads to relapse. A black-box warning for JAK inhibitors was extrapolated from safety data in a rheumatoid arthritis cohort; recent meta-analyses of JAK inhibitors used in dermatology cohorts do not demonstrate the same risk profile.

Safety and efficacy of tofacitinib in 97 alopecia areata patients

BACKGROUND

Alopecia areata (AA) is a recurrent immune-mediated disorder causing hair loss without any scarring being present. It affects hairs on the head or other parts of the body and can occur at any age and in both genders. It seems that AA is associated with a higher rate of psychological disorders resulting from hair loss and the esthetic and social repercussions of it. Common treatments like corticosteroids do not work for every patient and recent treatment options focusing on the immunologic mechanisms like tofacitinib have shown some promising results.

METHODS

It's a retrospective study on patients with AA, AT, AU taking oral tofacitinib as a treatment for at least 6 months. Scalp hair loss was assessed before treatment and at each visit using the Severity of Alopecia Tool (SALT) score.

RESULTS

Of 97 cases, 69.1% demonstrated over 50% SALT score improvement, with 44.3% having 90% or more decrease in SALT score. Patients who suffered from patchy AA were more responsive compared to patients with AT and AU subtypes and had a greater percent change in SALT score. Tofacitinib was tolerated quite well and no significant adverse events were reported.

CONCLUSIONS

Tofacitinib should be taken into consideration as an efficacious treatment option for patients with AA, AT and AU.

Disease burden, clinical management and unmet treatment need of patients with moderate to severe alopecia areata; consensus statements, insights, and practices from CERTAAE (Central/Eastern EU, Russia, Türkiye AA experts) Delphi panel

Objectives

This study aims to update the understanding of Alopecia Areata (AA) in Poland, Czechia, Russia, and Türkiye, focusing on the disease burden, clinical management, and patient journey. It seeks to establish a consensus on optimal management strategies for AA in these regions.

Methods

A modified 2-round Delphi panel was conveyed with 23 Dermatologists (Russia; 4, Türkiye; 7, Poland; 6, and Czechia; 6). The Delphi questionnaire consisted of 61 statements and 43 questions designed to obtain an overall understanding of the perception and acceptance of available information regarding the care of patients with alopecia areata.

Results

The study revealed that moderate-to-severe AA significantly impacts patients' and their families' QoL, consistent with previous studies. AA was found to cause more substantial impairment when additional lesions appeared in visible areas besides the scalp. Work and productivity impairment were notably higher in adults with moderate-to-severe AA. Diagnostic consensus highlighted the importance of skin biopsies and trichoscopy, while the need for more practical severity scoring systems was emphasized. Current treatments, including topical therapies, corticosteroids, and systemic immune modifiers, were deemed insufficient, highlighting the unmet medical need.

Conclusion

The Delphi study underscores a significant disease burden and unmet medical needs in patients with moderate-to-severe AA. It highlights the necessity of access to novel treatments and further research to develop more effective therapies with a tolerable safety profile. The findings align with global research, emphasizing the psychosocial impact of AA and the need for standardized, effective treatment protocols.

Comparative efficacy and safety of JAK inhibitors in the treatment of moderate-to-severe alopecia areata: a systematic review and network meta-analysis

We performed a Bayesian network meta-analysis to indirectly compare the relative efficacy and safety of the latest JAK inhibitors for moderate-to-severe alopecia areata (AA). 13 trials totaling 3,613 patients were included. Two low-dose groups of oral formulations (ritlecitinib 10mg and ivarmacitinib 2mg) and two topical formulations (delgocitinib ointment and ruxolitinib cream) appeared to be relatively ineffective against moderate-to-severe AA. Ranking analysis suggested that brepocitinib 30mg has the best relative effect in reducing the SALT score (sucra = 0.9831), and demonstrated comparable efficacy to deuruxolitinib 12mg (sucra = 0.9245), followed by deuruxolitinib 8mg (sucra = 0.7736). Regarding the SALT50 response, brepocitinib 30mg ranked highest (sucra = 0.9567), followed by ritlecitinib 50mg (sucra = 0.8689) and deuruxolitinib 12mg (sucra = 0.7690). For achieving the SALT75 response, deuruxolitinib 12mg had the highest probability (sucra = 0.9761), followed by deuruxolitinib 8mg (sucra = 0.8678) and brepocitinib 30mg (sucra = 0.8448). Deuruxolitinib 12mg might be the most effective therapy for patients with severe AA (sucra = 0.9395), followed by ritlecitinib 50mg (sucra = 0.8753) and deuruxolitinib 8mg (sucra = 0.8070). Deuruxolitinib 12mg/8mg demonstrated notable efficacy for moderate-to-severe AA, and is expected to be a new treatment option for AA. It was worth noting that deuruxolitinib exhibit a greater likelihood of causing adverse events in comparison to other JAK inhibitors. Ritlecitinib 50mg seemed to exhibit fewer adverse effects in the high-dose groups of oral JAK inhibitors and might be an optimal choice to balance safety and efficacy. The majority of JAK inhibitors exhibited acceptable short-term safety profiles. To enhance the applicability and accuracy of our research, further head-to-head trials with longer follow-up periods are needed. Systematic Review Registration: identifier [CRD42022368012].

Characteristics and Management of Patients with Alopecia Areata and Selected Comorbid Conditions: Results from a Survey in Five European Countries

INTRODUCTION

Alopecia areata (AA) is an autoimmune condition that causes non-scarring hair loss and can impose a high psychosocial burden on patients. The presence of comorbid conditions may impact the management of AA in clinical practice. This analysis aims to describe disease characteristics and management of AA in patients with concomitant atopic, autoimmune, and psychiatric comorbid conditions.

METHODS

Data were collected from the Adelphi Disease Specific Programme™, a cross-sectional survey of physicians and their adult patients with AA conducted in France, Germany, Italy, Spain, and the UK between October 2021 and June 2022. Patients' disease severity was based on physician's definition. Physician-reported data on demographics, AA clinical characteristics, comorbid conditions, and information related to AA therapies were analyzed. Analyses were descriptive.

RESULTS

Overall, 239 dermatologists provided data for 2083 patients, of which 558 patients (27%) had at least one atopic, autoimmune, or psychiatric comorbid conditions. The most common comorbid conditions were atopic dermatitis, autoimmune thyroid disease, and anxiety. The mean (standard deviation) patient age for the three comorbidity groups was 37.6 years (12.1) and 56% of the patients were women (n = 313). In the three comorbidity groups, 51%, 50%, and 55% of patients with atopic, autoimmune, and psychiatric comorbidities had severe AA with disease progression reported as worsening in 30%, 28%, and 30%, respectively, whereas in the group with no comorbidities, 37% were described as having severe AA and 21% getting worse. Scalp hair loss was the primary sign reported across the three groups of comorbid conditions (atopic, 91%; autoimmune, 91%; psychiatric, 88%). Patients with preselected comorbidities presented more frequently AA-related signs and symptoms beyond scalp hair loss than patients without comorbid conditions. These patients were also more likely to receive topical calcineurin inhibitors, topical immunotherapy, conventional systemic immunosuppressants, and oral Janus kinase inhibitors for the treatment of their AA.

CONCLUSION

This analysis provided insights into the burden and management of AA in patients presenting with atopic, autoimmune, and psychiatric comorbid conditions in five European countries.

[Janus kinase inhibitors : Indications, efficacy, uses, what should be taken into account?]

Janus kinase inhibitors (JAKi) represent an immunomodulatory targeted therapy in various dermatoses. Throughout the past few years, JAKi have been approved for atopic dermatitis (AD), psoriasis vulgaris (PSO), alopecia areata (AA), and vitiligo. Further indications are currently under investigation. In this article the various systenic and topical JAKi used in dermatology are being presented regarding their efficacy and safety profile. A specific focus will be set on handling with safety issues including screening and control measures during treatment with JAKi. In addition, future use of JAKi in various dermatological diseases for which nowadays only insufficient therapy options are available is being discussed.

Effectiveness of oral tofacitinib treatment on patients with moderate-to-severe alopecia areata in Iran

INTRODUCTION

Alopecia areata is an inflammatory hair loss and a common autoimmune disease. Conducting treatment studies on alopecia areata is difficult due to unpredictable periods and even spontaneous recovery from the disease. In this study, the effectiveness of tofacitinib in treating alopecia areata was investigated.

MATERIALS AND METHODS

The severity of the disease was evaluated using the Alopecia Severity Tool (SALT), and based on the medical history and patient's documents and photos, the score before and after the treatment was obtained. The patients were prescribed tofacitinib tablets at a dose of 5 mg twice a day for at least 6 months and were followed for a minimum of 18 months.

RESULTS

No side effect was observed in 97.9% of the patients. After 6 months, except for three patients who did not need any maintenance dose, others needed an average daily intake of 7 mg of tofacitinib. After 18 months, the hair loss decreased by 6.45 times compared to the beginning and by 0.5 times compared to the end of 6 months (p < 0.05). In addition, it was found that body hair loss decreased 4 times compared to the beginning and 0.6 times compared to the end of 6 months (p < 0.05). The reduction of nail involvement after 18 months and 6 months was 1.2 times and 0.6, respectively, (p < 0.05).

CONCLUSION

Treatment of alopecia areata with tofacitinib is recommended due to its effectiveness in reducing hair loss on the head, body, and nail involvement with few reversible side effects.

Long-term efficacy and safety of baricitinib in patients with severe alopecia areata: 104-week results from BRAVE-AA1 and BRAVE-AA2

BACKGROUND

Efficacy of the Janus kinase (JAK) inhibitor baricitinib for severe alopecia areata (AA) continuously increased over 52 weeks in two Phase 3 trials. There are limited long-term data on JAK inhibitors in AA.

OBJECTIVES

To evaluate efficacy and safety of baricitinib for severe AA through 104 weeks of continuous therapy.

METHODS

Integrated data from the BRAVE-AA1 and BRAVE-AA2 Phase 3 trials included adults with Severity of Alopecia Tool (SALT) scores ≥50 (≥50% scalp hair loss) randomized to and continuously treated with 2-mg or 4-mg baricitinib through Week 104. Patients who qualified to remain on continuous treatment included subjects who achieved SALT score ≤20 at Week 52 (Week-52 responders; 2-mg: N = 65; 4-mg: N = 129) and baricitinib 4-mg-treated patients who had SALT score >20 at Week 52 but achieved SALT score ≤20 at prior visit(s) and/or had significant improvement in eyebrow or eyelash hair growth relative to baseline by Week 52 (Week-52 mixed responders; N = 110). Week-104 outcomes included the proportion of patients achieving SALT score ≤20 (≤20% scalp hair loss). Data were censored after treatment discontinuation.

RESULTS

Among baricitinib 4-mg-treated and baricitinib 2-mg-treated Week-52 responders, 90.7% and 89.2%, respectively, maintained SALT score ≤20 at Week 104. Among Week-52 mixed responders, 39.1% reached SALT score ≤20 by Week 104. Continued improvement in eyebrow and eyelash regrowth was observed across groups. The most frequent treatment-emergent adverse events were COVID-19, upper respiratory tract infection, headache, nasopharyngitis, acne, urinary tract infection and creatine phosphokinase increase.

CONCLUSIONS

Baricitinib demonstrated a high level of maintenance of efficacy over 104 weeks in patients with severe AA. Efficacy increased in Week-52 mixed responders, illustrating that long-term treatment is necessary to observe maximum benefit in some patients. No new safety signals were observed.

Tumor necrosis factor inhibitors and janus kinase inhibitors in the treatment of cicatricial alopecia: A systematic review

BACKGROUND

Cicatricial alopecia (CA) refers to various conditions that result in permanent hair loss. Treatment of CA has always been challenging. Regarding immune-mediated pathophysiology for many CA subtypes, the administration of Janus kinase (JAK) and tumor necrosis factor (TNF) inhibitors have potentiated the treatments of CA.

METHODS

After a thorough systematic search in PubMed/Medline, Embase, Web of Science, Scopus, Google Scholar, ClinicalTrials.gov, and WHO ICTRP, a total of 3,532 relevant records were retrieved and screened. Accordingly, 56 studies met the eligibility criteria and entered the review.

RESULTS

Among JAK inhibitors, oral tofacitinib was the most frequently reported and the most effective treatment in improving signs and symptoms of CA with minimal adverse effects (AEs). Baricitinib was another JAK inhibitor with sustained improvement while causing mild AEs. As a TNF inhibitor, adalimumab induced a rapid and stable improvement in signs and symptoms in most patients with rare, tolerable AEs. Thalidomide was the other frequently reported yet controversial TNF inhibitor, which caused a rapid and significant improvement in the condition. However, it may result in mild to severe AEs, particularly neuropathies. Infliximab is a TNF inhibitor with mostly favorable results, albeit in a few patients caused treatable dermatological AEs. Apremilast and certolizumab pegol caused an incomplete amelioration of signs and symptoms with no AEs. Lenalidomide is another TNF inhibitor that can induce temporary improvement in CA with probable AEs. It is noteworthy that utilizing adalimumab, infliximab, etanercept, golimumab, and an anonymous TNF inhibitor has induced paradoxical CA and other A.E.s in some patients.

CONCLUSION

Recent studies have recommended JAK and TNF inhibitors, especially oral tofacitinib and adalimumab, as a new modality or adjuvant therapy to previous medications for primary CA. Nonetheless, monitoring AEs on a regular basis is suggested, and further extensive studies are required before definitive recommendations.

Alopecia Areata: Current Treatments and New Directions

Alopecia areata is an autoimmune hair loss disease that is non-scarring and is characterized by chronic inflammation at the hair follicle level. Clinically, patients' presentation varies from patchy, circumscribed scalp involvement to total body and scalp hair loss. Current management is guided by the degree of scalp and body involvement, with topical and intralesional steroid injections as primarily first-line for mild cases and broad immunosuppressants as the mainstay for more severe cases. Until recently, the limited number of blinded, randomized, placebo-controlled clinical trials for this disease had made establishing an evidence-based treatment paradigm challenging. However, growing insights into the pathogenesis of alopecia areata through blood and tissue analysis of human lesions have identified several promising targets for therapy. T-helper (Th) 1/interferon skewing has traditionally been described as the driver of disease; however, recent investigations suggest activation of additional immune mediators, including the Th2 pathway, interleukin (IL)-9, IL-23, and IL-32, as contributors to alopecia areata pathogenesis. The landscape of alopecia areata treatment has the potential to be transformed, as several novel targeted drugs are currently undergoing clinical trials. Given the recent US FDA approval of baricitinib and ritlecitinib, Janus kinase (JAK) inhibitors are a promising drug class for treating severe alopecia areata cases. This article will review the efficacy, safety, and tolerability of current treatments for alopecia areata, and will provide an overview of the emerging therapies that are leading the revolution in the management of this challenging disease.

Diagnosis and Management of Alopecia Areata: A Saudi Expert Consensus Statement (2023)

Alopecia areata (AA) is a complex autoimmune disease manifesting as a chronic inflammatory disease characterized by non-scarring patches of hair loss over the face, scalp, and body. Several treatments have been proposed for AA, but none are curative nor achieve a state of remission. The present consensus statement aims to present the evidence- and experience-based recommendations on the diagnosis and management of AA in Saudi Arabia. The Ministry of Health in Saudi Arabia has opted to initiate a meeting of a multidisciplinary group to discuss and concede on this topic. Eight dermatology experts and clinical pharmacists convened in eight consensus meetings. All content presented in this document was agreed upon by this working group, including diagnosis and severity assessment, prognostic indicators, and therapeutic options for AA. Special consideration was given to special patient populations including pediatric patients and patients with less frequent presentations of AA. Updates of the current recommendations will take place as new evidence evolves in the treatment of AA.

The relative efficacy of monotherapy with Janus kinase inhibitors, dupilumab and apremilast in adults with alopecia areata: Network meta-analyses of clinical trials

BACKGROUND

Janus kinase (JAK) inhibitors, biologics, and phosphodiesterase-4 (PDE-4) inhibitors are recent therapies for alopecia areata (AA)-albeit, knowledge gaps exist for these agents' relative efficacy.

OBJECTIVES

We determined the relative efficacy and safety of monotherapy with the aforementioned agents in adults with AA.

METHODS

The literature was systematically searched; we used data from randomized trials that investigated the agents' efficacy-as per Severity of Alopecia Tool (SALT) scores. Bayesian network meta-analyses were used to determine relative efficacy and safety. Effect modification was determined using a generalized linear model on aggregate data; evidence quality was evaluated.

RESULTS

Based on the surface under the cumulative ranking curve estimates obtained from multiple efficacy endpoints, regimens with the highest likelihood of achieving percent reduction in SALT scores, as well as a minimum 90%, 75% or 50% reduction in SALT scores are (in alphabetical order) baricitinib 4 mg once daily (QD), brepocitinib 60/30 mg QD, deuruxolitinib (CTP-543) 12 mg twice daily (BID), ritlecitinib 200/50 mg QD, ruxolitinib 20 mg BID and tofacitinib 5 mg BID. In contrast, dupilumab subcutaneous injections administered weekly and apremilast 30 mg BID were less likely to be effective. Discontinuation due to any adverse event was the least likely with oral JAK inhibitors, and more likely with dupilumab and apremilast.

CONCLUSIONS

Our results support the conduct of high-quality comparative trials to determine whether JAK inhibitors are more effective and safer than PDE4 inhibitors.

Janus kinase inhibitors in autoimmune bullous diseases

Autoimmune bullous disease (AIBD) is a severe skin disorder caused by autoantibodies that target intercellular or cell-matrix adhesion proteins. Currently, the preferred treatment for AIBD involves the use of glucocorticoids or traditional immunosuppressants. Additionally, the utilization of biological agents such as rituximab, omalizumab, and dupilumab is on the rise. However, effectively managing AIBD remains a challenge. The Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway has been implicated in various inflammatory diseases. In recent years, a range of drugs known as JAK inhibitors, which target this pathway, have been developed. Several studies have explored the efficacy and safety of JAK inhibitors for treating AIBD. Consequently, this review begins by examining the role of the JAK/STAT pathway in AIBD, summarizing the application of different JAK inhibitors in AIBD treatment, and emphasizing the importance of disease management in treating AIBD with JAK inhibitors. Furthermore, it highlights the need for a better understanding of the JAK/STAT pathway's role in AIBD, as well as the effectiveness and safety of JAK inhibitors for treating this disease.

Which is the Ideal JAK Inhibitor for Alopecia Areata - Baricitinib, Tofacitinib, Ritlecitinib or Ifidancitinib - Revisiting the Immunomechanisms of the JAK Pathway

Alopecia areata (AA) is an immune-mediated condition, clinically manifesting as non-cicatricial patches of alopecia. It is often a self-limiting condition; however, regrowth of hair can take a long period of time, resulting in significant psychological comorbidity. With the recent advances in pathomechanisms of AA, the therapeutic approach to the condition has become more specific, and targeted therapy with small molecules is probably the ideal intervention. Many therapies exist for AA, but none of the systemic agents were approved, until recently, when baricitinib (Janus kinase (JAK1 and JAK2 inhibitor) gained FDA approval for the treatment of adult patients with severe AA. JAK inhibitors (JAKibs) target the γc cytokine and interferon-gamma (IFN-γ) signaling pathway, which is critical to the immunopathogenesis of AA and thus can reverse the hair loss in AA. Although JAKibs are emerging as a promising treatment modality for AA, the ideal JAKib is not yet settled, as there is scant data on H-2-H (head-to-head) comparisons of JAK inhibitors in AA. Moreover, the response achieved with JAKibs is not sustained after treatment discontinuation, with many studies showing a high recurrence rate with tofacitinib and ruxolitinib post-treatment. Also, recent studies have hypothesized that JAK2, with its ubiquitous expression, can cause adverse effects, unlike JAK1, which is associated with multiple major cytokine receptor families and JAK3, which is exclusively associated with the γc cytokine receptor. Thus, JAK3ibs may be associated with a better side effect profile and, in conjunction with their specificity, may replace other JAKibs as the treatment of choice for AA. We herein discuss the role of the JAK/STAT (signal transducer and activator of transcription) pathway in AA, the intricacies of various JAKibs in the management of AA, and emphasize the need for studies on tissue JAK and cytokine expression before arriving at the ideal JAKibs for AA.

Guidelines for the Management of Patients with Alopecia Areata in Korea: Part II Systemic Treatment

BACKGROUND

Alopecia areata (AA) is a chronic disease with an unpredictable course and can have a severe psychological impact on an individual.

OBJECTIVE

To provide evidence and consensus-based statements regarding the treatment of patients with AA in Korea.

METHODS

We searched for relevant studies from inception to May 2021 regarding the systemic treatment of AA. Evidence-based recommendations were also prepared. The evidence for each statement was graded and classified according to the strength of the recommendations. Hair experts from the Korean Hair Research Society (KHRS) voted on the statement, and an agreement of 75% or greater was considered as having reached consensus.

RESULTS

Current evidence supports the efficacy of systemic corticosteroids, oral cyclosporine monotherapy or combination with systemic corticosteroids, and oral Janus kinase inhibitors in severe AA patients. Systemic steroids may be considered for pediatric patients with severe AA. A consensus was achieved in three out of nine (33.3%), and one out of three (33.3%) statements pertaining to systemic treatment in adult and pediatric AA, respectively.

CONCLUSION

The present study produced up-to-date, evidence-based treatment guidelines for AA associated with the consensus obtained by experts based on the Korean healthcare system.

Baricitinib for the Treatment of Alopecia Areata

Alopecia areata (AA) is a relapsing, chronic, immune-mediated disease characterized by nonscarring, inflammatory hair loss that can affect any hair-bearing site. AA clinical presentation is heterogeneous. Its pathogenesis involves immune and genetic factors and several pro-inflammatory cytokines involved in AA pathogenesis, including interleukin-15 and interferon-γ, as well as Th2 cytokines, such as IL-4/IL-13, that signal through Janus kinase (JAK) pathway. AA treatment aims to stop its progression and reverse hair loss, and JAK inhibition has been shown to stop hair loss and reverse alopecia and has exhibited promising results in treating AA in clinical trials. Baricitinib, an oral, reversible, selective JAK1/JAK2 inhibitor, was shown to be superior to placebo on hair growth after 36 weeks of treatment in adults with severe AA in a phase 2 trial and recently in two phase 3 trials (BRAVE-AA1 and BRAVE-AA2). In both studies, the most common adverse events were upper respiratory tract infections, urinary tract infection, acne, headache, and elevated creatine kinase levels. On the basis of these trial results, baricitinib was recently approved by the European Medicines Agency (EMA) and US Food and Drug Administration (FDA) for the treatment of adults with severe AA. Nevertheless, longer trials are needed to determine the long-term efficacy and safety of baricitinib in AA. Current trials are ongoing and are planned to remain randomized and blinded for up to 200 weeks.

Biomarkers in alopecia Areata: A systematic review and meta-analysis

BACKGROUND

Alopecia areata (AA) is an autoimmune non-scarring alopecia that affects the scalp or any hair-bearing areas in the body. The pathophysiology of AA is complex, but Th1, Th2, and Th17 cytokines dysregulation, as well as chemokines, immunoglobulins and other biomarkers have been shown to play a role in the pathogenesis of the disease.

OBJECTIVE

To conduct a systematic review and Meta-analysis to identify biomarkers that reflect AA activity and severity that could be used to better assess disease activity and response in both trials and clinical practice.

METHODS

A literature search was conducted using the PUBMED, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception to December 2021. Articles reporting on associations between AA and serum clinical biomarkers (cytokines, chemokines, antibodies, immunoglobulins, and others) were included. Serum biomarkers were identified in patients with AA and were correlated with disease severity and patient characteristics (ex. age, sex, comorbidities). The quality of the studies was assessed using the National Heart, Lung, and Blood Institute's Quality Assessment Tool for Case-Control Studies. Meta-analysis pooling of the standardized mean differences (SMD) by the method of Cohen using the common-effect inverse-variance model was performed. For the Meta-analysis, data was pulled for all the markers with a minimum of 4 studies with means and standard deviations. Analysis of data reported as Median with range or inter-quartile range (IQR) revealed that the data was too skewed to recommend calculation and use of mean with standard deviation (SD). If the data were not skewed, mean and SD were calculated.

RESULTS

One thousand seven hundred fourteen studies were screened, with 91 included, reporting on a total of 52 biomarkers. Meta-analyses revealed pooled SMD that were significant for interleukin 6 (IL6), C-reactive protein (CRP) and vitamin D.

CONCLUSIONS

Serum IL6 and CRP levels are significantly increased in patients with AA compared to healthy age and sex matched controls. Conversely, serum vitamn D levels are significantly decreased in patients with AA compared to healthy age and sex matched controls. This data has the potenail to influence the clinical guidelines for the diagnostic workup of AA to include testing the serum levels of CRP and vitamin D.

Innovative Strategies for Hair Regrowth and Skin Visualization

Today, about 50% of men and 15-30% of women are estimated to face hair-related problems, which create a significant psychological burden. Conventional treatments, including drug therapy and transplantation, remain the main strategies for the clinical management of these problems. However, these treatments are hindered by challenges such as drug-induced adverse effects and poor drug penetration due to the skin's barrier. Therefore, various efforts have been undertaken to enhance drug permeation based on the mechanisms of hair regrowth. Notably, understanding the delivery and diffusion of topically administered drugs is essential in hair loss research. This review focuses on the advancement of transdermal strategies for hair regrowth, particularly those involving external stimulation and regeneration (topical administration) as well as microneedles (transdermal delivery). Furthermore, it also describes the natural products that have become alternative agents to prevent hair loss. In addition, given that skin visualization is necessary for hair regrowth as it provides information on drug localization within the skin's structure, this review also discusses skin visualization strategies. Finally, it details the relevant patents and clinical trials in these areas. Together, this review highlights the innovative strategies for skin visualization and hair regrowth, aiming to provide novel ideas to researchers studying hair regrowth in the future.

Recent advances in the genetics of alopecia areata

Alopecia areata (AA) is a common autoimmune-mediated hair loss disorder in humans with an estimated lifetime risk of approximately 2 %. Episodes of hair loss usually begin with isolated hairless patches that may progress to complete hair loss over the entire body. A familial occurrence of AA is well established, with recurrence risks of about 6–8 % in first-degree relatives. AA is a multifactorial disorder involving both environmental and genetic risk factors. Previous research has identified 14 susceptibility loci, most of which implicate genes involved in the immune response. The following review presents a summary of the latest findings from genome-wide association, sequencing and gene expression studies of AA, as well as their contribution to the recent therapeutic developments.

JAK inhibitors in dermatology: the road travelled and path ahead, a narrative review

INTRODUCTION

Numerous cutaneous dermatoses mediated by cytokines depend on the JAK STAT pathway for intracellular signaling. JAK inhibitors form a useful therapeutic approach in treating these conditions. The literature on effectiveness of JAK inhibitors in treatment of alopecia areata, vitiligo, atopic dermatitis, psoriasis and several other inflammatory and autoimmune diseases is growing, although very few conditions have sufficiently well performed studies to their credit and barring a few indications, their use in rest remains empirical as yet.

AREAS COVERED

A search of the PubMed database was made using the keywords Janus kinase inhibitors OR JAK inhibitors AND dermatology with the time duration limited to the last 5 years. Here, we review the JAK STAT pathway and the various conditions in which JAK inhibitors are currently used in dermatology and other conditions their use is being explored in.

EXPERT OPINION

The pathology of a large number of dermatological disorders is mediated via inflammatory cytokines which signal via the JAK STAT pathway. JAKinibs have shown great promise in treating cutaneous disorders refractory to conventional therapy. Their current clinical use in dermatology is based on robust evidence (for some), and anecdotal evidence for most other dermatoses.

Identification, Synthesis, and Characterization of Novel Baricitinib Impurities

Baricitinib is a novel active pharmaceutical ingredient used in the treatment of rheumatoid arthritis, and it acts as an inhibitor of Janus kinase. During the synthesis of baricitinib, three unknown impurities were identified in several batches between 0.10 and 0.15% using high-performance liquid chromatography. The unknown compounds were isolated and identified as N-((3-(4-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)-5-oxotetrahydrofuran-3-yl)methyl)ethane sulfonamide (lactone impurity, BCL), 2-(3-(4-(7H-[4,7'-bipyrrolo[2,3-d]pyrimidin]-4'-yl)-1H-pyrazol-1-yl)-1-(ethylsulfonyl)azetidin-3-yl)acetonitrile (dimer impurity, BCD), and 2-(1-(ethylsulfonyl)-3-(4-(7-(hydroxymethyl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)azetidin-3-yl) acetonitrile (hydroxymethyl, BHM). These compounds were synthesized and confirmed against the isolated samples. The structures of all the three impurities were confirmed by extensive analysis of ¹H NMR, ¹³C NMR, and mass spectrometry. The lactone impurity formation was explained by a plausible mechanism. The outcome of this study was very useful for scientists working in process as well as in formulation development. To synthesize highly pure baricitinib drug substance, these impurities can be used as reference standards due to their potential importance.

Efficacy and Safety of Baricitinib in Patients with Severe Alopecia Areata over 52 Weeks of Continuous Therapy in Two Phase III Trials (BRAVE-AA1 and BRAVE-AA2)

BACKGROUND

The oral Janus kinase (JAK) inhibitor baricitinib has demonstrated efficacy for severe alopecia areata (AA) over 36 weeks. There are limited data on the longer-term treatment of AA.

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of baricitinib for AA in adults with ≥50% scalp hair loss through 52 weeks of continuous therapy in two phase III trials (BRAVE-AA1 and BRAVE-AA2).

METHODS

Patients randomized to baricitinib at baseline in BRAVE-AA1 (N = 465) and BRAVE-AA2 (N = 390) retained their treatment allocation through Week 52. Efficacy outcomes included the proportion of patients achieving a Severity of Alopecia Tool (SALT) score ≤ 20 (≤ 20% scalp hair loss). Data were censored after permanent treatment discontinuation or if collected remotely due to the coronavirus disease 2019 (COVID-19) pandemic.

RESULTS

Response rates for hair regrowth increased over the 52-week period. Of patients treated with baricitinib 4 mg and 2 mg, respectively, 40.9% and 21.2% in BRAVE-AA1 and 36.8% and 24.4% in BRAVE-AA2 achieved a SALT score ≤ 20 at Week 52. The most frequent treatment-emergent adverse events included upper respiratory tract infection, headache, nasopharyngitis, acne, urinary tract infection, creatine phosphokinase elevation, and COVID-19 infection.

LIMITATION

There were no comparisons with placebo.

CONCLUSION

Efficacy of baricitinib for adults with severe AA continuously improved over 52 weeks, indicating that long-term treatment may be necessary to observe maximum clinical benefit. There were no new safety signals.

CLINICALTRIALS REGISTRATION

ClinicalTrials.gov NCT03570749 and NCT03899259. Efficacy and Safety of Baricitinib in Patients with Severe Alopecia Areata: Week-52 Results from BRAVE-AA1 and BRAVE-AA2.

A phase 2a randomized vehicle-controlled multi-center study of the safety and efficacy of delgocitinib in subjects with moderate-to-severe alopecia areata

Alopecia areata/AA is an autoimmune cause of nonscarring hair loss. The pathogenesis of AA involves many immune axes, including Th1/Th2 pathways. Delgocitinib is a pan-Janus kinase/JAK inhibitor that broadly blocks pro-inflammatory cytokines and has been effective in other inflammatory skin conditions. Recent human studies/reports have shown that use of some systemic JAK inhibitors led to hair regrowth, suggesting this medication class as a potential therapy for AA. However, topical treatment is desirable due to potential systemic side effects. To assess the efficacy and safety of topical delgocitinib in AA, we conducted a double-blind, randomized, vehicle-controlled clinical trial in 31 moderate-to-severe AA patients that were randomized 2:1 to receive delgocitinib ointment 30 mg/g (n = 20) or ointment vehicle (n = 11) for 12 weeks. The primary endpoint was change in severity of Alopecia Tool/SALT score from baseline to week 12. The secondary endpoint included safety profile by reported adverse events. Twenty-three subjects completed the trial, with eight discontinuing mostly due to voluntary withdrawal. Ten patients receiving delgocitinib ointment and three patients receiving vehicle showed SALT score improvements after 12 weeks, but the mean percent SALT improvement at week 12 compared to baseline between the two arms was not significant (p = 0.92). Our study suggests that delgocitinib ointment is not effective in moderate-to-severe AA, likely due to its inability to penetrate sufficiently deeply into the dermis of the scalp, but larger studies are necessary to assess whether a different formulation of topical JAK inhibitors may be suitable to treat mild or more localized forms of AA.

Granzyme B in Autoimmune Skin Disease

Autoimmune diseases often present with cutaneous symptoms that contribute to dysfunction, disfigurement, and in many cases, reduced quality-of-life. Unfortunately, treatment options for many autoimmune skin diseases are limited. Local and systemic corticosteroids remain the current standard-of-care but are associated with significant adverse effects. Hence, there is an unmet need for novel therapies that block molecular drivers of disease in a local and/or targeted manner. Granzyme B (GzmB) is a serine protease with known cytotoxic activity and emerging extracellular functions, including the cleavage of cell-cell junctions, basement membranes, cell receptors, and other structural proteins. While minimal to absent in healthy skin, GzmB is markedly elevated in alopecia areata, interface dermatitis, pemphigoid disease, psoriasis, systemic sclerosis, and vitiligo. This review will discuss the role of GzmB in immunity, blistering, apoptosis, and barrier dysfunction in the context of autoimmune skin disease. GzmB plays a causal role in the development of pemphigoid disease and carries diagnostic and prognostic significance in cutaneous lupus erythematosus, vitiligo, and alopecia areata. Taken together, these data support GzmB as a promising therapeutic target for autoimmune skin diseases impacted by impaired barrier function, inflammation, and/or blistering.

Effect of fractional laser alone or in combination on alopecia areata: A systematic review and meta-analysis

BACKGROUND

Alopecia areata (AA) is characterized by limited non-scarring patchy alopecia, which appears as round or oval patches and is prone to recurrence, causing severe psychological burdens to patients. No specific device has been approved by the FDA for the treatment of baldness, but new treatments are being investigated and treatments such as the excimer laser, He- Ne laser, and excimer lamp have been proposed. A growing number of studies have found that fractional lasers also have great potential in the treatment of AA.

METHODS

A literature search and meta-analysis using Review Manager 5.4 software to investigate the efficacy of fractional laser treatment for AA.

RESULTS

Fractional laser combined with minoxidil (RR 1.32, 95% CI 1.17-1.49, p < 0.00001) or cortisol (RR 1.39, 95% CI 1.15-1.67, p = 0.00006) was more effective than either drug alone in the treatment of AA. Of course, the fractional laser alone was also effective in the treatment of AA (RR 10.33, 95% CI 2.07-51.36, p = 0.004) and more effective than cortisol alone (RR 1.86, 95% CI 1.36-2.52, p < 0.00001), and there was no effect on the occurrence of adverse effects (p = 0.49 > 0.05). When compared to other physical treatments of a comparable kind, fractional laser therapy's effectiveness was not significantly different (p = 0.15 > 0.05).

CONCLUSION

Our results show that the use of fractional lasers can effectively treat alopecia areata.

Comparative Efficacy and Safety of Janus Kinase Inhibitors Used in Alopecia Areata: A Systematic Review and Meta-analysis

The aim of this study was to compare the efficacy and safety of treatment with Janus kinase inhibitors for alopecia areata, measured by change in Severity of Alopecia Tool (SALT) score. A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines was performed using Medline, EMBASE and Cochrane library. All studies investigating the efficacy of treatments for alopecia areata were included. Primary outcomes were the proportion of patients with alopecia areata achieving 30%, 50%, 75%, 90% and 100% improvement in SALT score after treatment with a Janus kinase inhibitor. A meta-analysis was performed including all randomized controlled trials investigating Janus kinase inhibitors. A total of 37 studies matched the inclusion criteria and were included. Meta-analysis was performed based on 5 randomized studies. Regarding patients with alopecia areata defined as ≥ 50% scalp hair loss, baricitinib 4 mg once daily demonstrated the highest efficacy. However, among patients with alopecia areata defined as a SALT score ≥ 50, oral deuruxolitinib 12 mg twice daily demonstrated the highest efficacy. Deuruxolitinib and baricitinib appear to be promising drugs for the treatment of alopecia areata. However, the response depends on the dosage of the drug. More randomized trials, with identical inclusion criteria and dose and duration of treatment, are required to confirm these findings.

Out-of-Pocket Costs in Alopecia Areata: A Cross-Sectional Study in German-speaking Countries

Alopecia areata is a common skin disease which is associated with psychosocial and financial burden. No curative therapy exists and, hence, affected persons resort to self-financed cosmetic solutions. However, studies on the economic impact of alopecia areata on individuals are limited. To estimate annual individual out-of-pocket costs in persons with alopecia areata, a cross-sectional study using a standardized online questionnaire was performed in Germany, Austria and Switzerland. A total of 346 individuals (95.1% women, mean age: 38.5 ± 11.6 years) with alopecia areata participated between April and August 2020. Mean additional spending on everyday necessities was 1,248€ per person per year, which was significantly influenced by the duration of the illness, the treatment provider, and disease severity. Hair replacement products and cosmetics accounted for the highest monthly costs, followed by costs for physician visits, hospital treatments, and medication. Most participants (n = 255, 73.7%) were currently not undergoing treatment, due to lack of efficacy, side-effects, costs and acceptance of the disease. Sex differences in expenses were observed, with women having higher expenditures. Alopecia areata-related out-of-pocket costs place a considerable financial burden on affected individuals, are higher compared with those of other chronic diseases, and should be considered in economic assessments of the impact of this disease.

Topical SCD-153, a 4-methyl itaconate prodrug, for the treatment of alopecia areata

Alopecia areata is a chronic hair loss disorder that involves autoimmune disruption of hair follicles by CD8⁺  T cells. Most patients present with patchy hair loss on the scalp that improves spontaneously or with topical and intralesional steroids, topical minoxidil, or topical immunotherapy. However, recurrence of hair loss is common, and patients with extensive disease may require treatment with oral corticosteroids or oral Janus kinase (JAK) inhibitors, both of which may cause systemic toxicities with long-term use. Itaconate is an endogenous molecule synthesized in macrophages that exerts anti-inflammatory effects. To investigate the use of itaconate derivatives for treating alopecia areata, we designed a prodrug of 4-methyl itaconate (4-MI), termed SCD-153, with increased lipophilicity compared to 4-MI (CLogP 1.159 vs. 0.1442) to enhance skin and cell penetration. Topical SCD-153 formed 4-MI upon penetrating the stratum corneum in C57BL/6 mice and showed low systemic absorption. When added to human epidermal keratinocytes stimulated with polyinosinic-polycytidylic acid (poly I:C) or interferon (IFN)γ, SCD-153 significantly attenuated poly I:C-induced interleukin (IL)-6, Toll-like receptor 3, IL-1β, and IFNβ expression, as well as IFNγ-induced IL-6 expression. Topical application of SCD-153 to C57BL/6 mice in the resting (telogen) phase of the hair cycle induced significant hair growth that was statistically superior to vehicle (dimethyl sulfoxide), the less cell-permeable itaconate analogues 4-MI and dimethyl itaconate, and the JAK inhibitor tofacitinib. Our results suggest that SCD-153 is a promising topical candidate for treating alopecia areata.

The potential of regulatory T cell-based therapies for alopecia areata

Cytotoxic T lymphocyte has been a concern for the etiopathogenesis of alopecia areata (AA), some recent evidence suggests that the regulatory T (T_reg) cell deficiency is also a contributing factor. In the lesional scalp of AA, T_reg cells residing in the follicles are impaired, leading to dysregulated local immunity and hair follicle (HF) regeneration disorders. New strategies are emerging to modulate T_reg cells' number and function for autoimmune diseases. There is much interest to boost T_reg cells in AA patients to suppress the abnormal autoimmunity of HF and stimulate hair regeneration. With few satisfactory therapeutic regimens available for AA, T_reg cell-based therapies could be the way forward. Specifically, CAR-T_reg cells and novel formulations of low-dose IL-2 are the alternatives.

An Updated Review on Current Treatment of Alopecia Areata and Newer Therapeutic Options

Alopecia areata (AA) is a dermatological disease that causes nonscarring hair loss. It can occur at any age and has an unpredictable and variable evolution in individuals. The aim of this review is to provide an update on the novel therapies currently being used, as well as upcoming therapeutic options in the treatment of AA.

Alopecia Areata: Burden of Disease, Approach to Treatment, and Current Unmet Needs

Alopecia areata is an autoimmune hair loss disorder with variations in distribution, duration, and severity. The disease is chronic and often follows an unpredictable course, frequently leading to stress and anxiety for those who suffer from it. Throughout the years more knowledge has been gained regarding pathogenesis, diagnostic tools, impact on quality of life, as well as treatment strategies for alopecia areata. However, challenges in treating and alleviating the burden of disease remain. In this article, we discuss updates regarding the pathogenesis and treatment of alopecia areata and highlight unmet needs of the condition, including a review of limitations of current treatments, accessibility to management strategies, and the need for disease awareness and advocacy.

Alopecia Areata in Latin America: Where are We and Where are We Going?

Alopecia areata (AA) represents an underrecognized burden in Latin America (LA), severely impacting quality of life (QoL). This impact is exacerbated by limited access to specialized dermatologic care and therapies for AA within and among nations. Many of the unmet needs for AA globally also exist in LA. The region has geographic, ethnic, cultural, and economic conditions. With new AA medicines targeting immunologic pathways on the horizon, LA must prepare regarding regulatory issues, reimbursement, awareness, and education to give adequate and timely treatment for patients with AA. To address these issues, the Americas Health Foundation convened a panel of six dermatologists from Argentina, Brazil, Colombia, and Mexico who are experts in AA and its comorbidities for a 3-day virtual meeting to discuss AA diagnosis and treatment in LA and create a manuscript offering recommendations to address discussed barriers. This publication examines unmet AA needs in LA, treatment, and innovative therapies and recommends improving AA care. Access constraints to conventional and novel medicines hinder appropriate treatments for patients. Therapy initiation delays can affect QoL, mental health, and disease progression. People with AA face stigmas, discrimination, and misconceptions owing to a lack of disease awareness. With promising new treatments for AA on the horizon, all stakeholders must coordinate efforts to enhance LA's AA management landscape and improve patient outcomes.

Alopecia Areata: Case report and review of pathophysiology and treatment with Jak inhibitors

Alopecia Areata (AA) is a T-cell mediated autoimmune attack on hair follicles resulting in rapidly developing areas of hair loss involving the scalp and beard that can progress to total scalp hair loss (alopecia totalis) and loss of eyebrows, eyelashes, and total body hair (alopecia universalis). Affected patients have high rates of psychological disorders and decreased quality of life. There are no FDA approved treatments, and the available treatments have a high failure rate. JAK inhibitors are remarkably effective in many autoimmune diseases including Alopecia Areata. Presented is a case report of successful treatment with tofacitinib, and a literature review of the pathophysiology of alopecia areata, the mechanism of action of JAK inhibitors, and the JAK inhibitors in phase 2 and 3 trials.

Efficacy and safety of tofacitinib for treatment of alopecia areata in children: A systematic review and meta-analysis

BACKGROUND

Tofacitinib, a potent JAK inhibitor, has gained increasing interest, in recent years, among dermatologists for the management of refractory alopecia areata. Despite a growing number of studies on its safety and efficacy, there is still a lack of clarity, especially in the pediatric population, in treatment considerations such as proper dosage, treatment duration, side-effect profile, and therapeutic strategies to guide clinicians.

METHODS

Multiple databases were systematically searched. Following the PRISMA diagram, of a pool of 601 papers, seven met a checklist of inclusion criteria. These were observational studies including a total of 59 patients from four to 19 years of age.

RESULTS

In the evaluated studies, tofacitinib was administered either orally at a 2.5 to 15 mg daily (mostly 5 mg twice a day) dosage for 2 to 38 months or in the form of a 2% topical solution for 3-17 months. Metanalysis showed that 49% (95% CI: 29%-69%, I²  = 59.94%) of patients experienced a reversal of alopecia after a minimum of 3 to 9 months of therapy. Fifty-five percent (95% CI: 23%-86%, I²  = 75.07%) and 41% (95% CI: 23%-59%, I²  = 0.00%) showed Good/complete and partial response rates, respectively. Oral administration was significantly more efficacious than topical application (73% vs 23%, p-Value = 0.04). Few side effects such as diarrhea and mild liver transaminases abnormalities were noted in several patients.

CONCLUSION

Results of this review suggest that tofacitinib at 2.5-15 mg daily (especially 5 mg twice daily) oral formulation or 2% topical solution can be regarded as a viable alternative or adjunct to the conventional treatment options for moderate to severe forms of alopecia areata in children owing to its acceptable efficacy and side-effect profile. However, uncertainties continue to exist around treatment strategies including initial and maintenance dosages, route of administration, dose adjustments, the timing of tapering or discontinuation, and associated treatment modalities.

Real-world experience and long-term evaluation of tofacitinib in refractory alopecia areata: A prospective, open-label, single-center study in Asian Arab population

Tofacitinib is a pan-janus kinase inhibitor (JAK) which has been tested off-label in alopecia areata (AA) with promising results. However, evidence of tofacitinib in real-life setting is still poor. We evaluated long-term efficacy and safety of tofacitinib for refractory AA. This is a prospective, open-label, observational, single-center cohort study conducted between January 2018 and December 2020. Primary end-point was the percent change in Severity of Alopecia Tool (SALT) at the basal visit and at the most recent follow-up visit. Three categories of treatment response were analyzed. Data on 47 participants of Arab-Asian heritage were analyzed. A complete and partial regrowth was observed in 18 patients (41.86%) and 11 patients (25.58%), respectively. In 12 patients (27.9%), no response was obtained. Most of the non-responders belonged to the alopecia universalis group (66.67%). No statistical differences were observed in rates of regrowth between pediatric and adult individuals (p = 0.52), nor between women and men. Significant differences in the average duration of tofacitinib treatment were obtained among the three categories of regrowth (p < 0.003), notably duration of AA did not impact the clinical regrowth (p = 0.62). To the best of our knowledge, this is the first prospective, observational, long-term study using tofacitinib in refractory AA. Rates of regrowth and side effects are analogous to previous works. Length of tofacinitib therapy should last for 12 months before considering any discontinuation or change, since early cessation can lead to treatment failures or incomplete regrowth. Maintenance therapy after complete regrowth has demonstrated to be safe and effective to prevent recurrences of hair loss.

Upadacitinib for the treatment of alopecia areata and severe atopic dermatitis in a paediatric patient: A case report

This case report describes the first successful treatment of alopecia areata and atopic dermatitis with the Janus kinase 1 inhibitor upadacitinib in a paediatric patient. After minimal response to topical corticosteroids and spironolactone, improvements in hair growth on the scalp and body were noted after only 6 weeks of upadacitinib treatment.

Ex Vivo Treatment with Allogenic Mesenchymal Stem Cells of a Healthy Donor on Peripheral Blood Mononuclear Cells of Patients with Severe Alopecia Areata: Targeting Dysregulated T Cells and the Acquisition of Immunotolerance

Alopecia areata (AA) is an autoimmune condition related to the collapse of the immune privilege of hair follicles. Certain AA populations present severe clinical manifestations, such as total scalp hair or body hair loss and a treatment refractory property. The aim of this study was to assess the effects of allogenic human mesenchymal stem cells (hMSCs) from healthy donors on the peripheral blood mononuclear cells (PBMCs) of severe AA patients, with a focus on the change in the cell fraction of Th1, Th17, and Treg cells and immunomodulatory functions. PBMCs of 10 AA patients and eight healthy controls were collected. Levels of Th17, Th1, and Treg subsets were determined via flow cytometry at baseline, activation status, and after co-culturing with hMSCs. All participants were severe AA patients with SALT > 50 and with a long disease duration. While the baseline Th1 and Treg levels of AA patients were comparable to those of healthy controls, their Th17 levels were significantly lower than those of the controls. When stimulated, the levels of CD4+IFN-γ+ T cells of the AA patients rose sharply compared to the baseline, which was not the case in those of healthy controls. The cell fraction of CD4+Foxp3+ regulatory T cells also abruptly increased in AA patients only. Co-culturing with allogenic hMSCs in activated AA PBMCs slightly suppressed the activation levels of CD4+INF-γ+ T cells, whereas it significantly induced the differentiation of CD4+Foxp3+ regulatory T cells. However, these changes were not prominent in the PBMCs of health controls. To examine the pathomechanisms, PBMCs of healthy donors were treated with IFN-γ to induce AA-like environment and then treated with allogenic grants and compared with ruxolitinib as a positive treatment control. hMSC treatment was shown to significantly inhibit the mRNA levels of proinflammatory cytokines, such as IFN-γ, TNF-α, IL-1α, IL-2R, IL-15, and IL-18, and chemokines, such as CCR7 and CCR10, in IFN-treated PBMCs. Interestingly, hMSCs suppressed the activation of JAK/STAT signaling by IFN in PBMCs with an effect that was comparable to that of ruxolitinib. Furthermore, the hMSC treatment showed stronger efficacy in inducing Foxp3, IL-10, and TGF-β mRNA transcription than ruxolitinib in IFN-treated PBMCs. This study suggests that allogenic hMSC treatments have therapeutic potential to induce immune tolerance and anti-inflammatory effects in severe AA patients.

The implications of IL-15 trans-presentation on the immune response

Interleukin-15 is a pleiotropic cytokine type I four alpha-helical bundle cytokine that along with IL-2, IL-4, IL-7, IL-9, and IL-21 shares the common cytokine receptor γ chain, γ_c. IL-15 is vital for the development, survival, and expansion of natural killer cells and for the development of CD8⁺ memory T cells. Whereas other family γ_c cytokines signal by directly binding to their target cells, IL-15 is distinctive in that it binds to IL-15Rα, a sushi domain containing binding protein that is expressed on a number of cell types, including monocytes and dendritic cells as well as T cells, and then is trans-presented to responding cells that express IL-2Rβ and γ_c. This distinctive mechanism for IL-15 relates to its role in signaling in the context of cell-cell interactions and signaling synapses. The actions of IL-15 and ways of manipulating its actions to potential therapeutic benefit are discussed.