Alopecia Areata Is Associated with Atopic Diathesis: Results from a Population-Based Study of 51,561 Patients

Genetic association between asthma and alopecia areata: A two-sample Mendelian randomization study

BACKGROUND

Many patients with asthma experience alopecia areata (AA) in their lives. However, it is unclear whether asthma causes or results from AA. Our objective was to investigate the genetic causal relationship between asthma and AA.

METHODS

Two-sample Mendelian randomization (MR) was used to assess the causal relationship between asthma and AA based on the largest publicly available genome-wide association study summary statistics. Androgenetic alopecia (AGA) and cicatricial alopecia (CA) were chosen as the control groups for AA. The main estimates were obtained using inverse variance weighting meta-analysis (IVW), Mendelian randomization-Egger (MR-Egger), maximum likelihood estimation, and the weighted median. Sensitivity analyses were conducted using Cochran's Q test, MR-Egger, and leave-one-out methods. Lastly, we conducted a reverse MR analysis to evaluate the possibility of reverse causation.

RESULTS

Genetically, asthma is associated with an increased risk of AA, while the association between genetically predicted AGA or CA and asthma was negative. The risk of AA increased by 1.86 times in patients with asthma under the IVW method (OR = 1.86, 95% CI = 1.31-2.629, p < 0.001). The reverse MR analysis did not find evidence supporting reverse causality from three phenotypes of alopecia to asthma. Sensitivity analyses yielded consistent causal estimates.

CONCLUSION

This study suggests that asthma is causally associated with AA. The findings deepen our understanding of the role of asthma in the pathology of AA, which emphasizes the potential for opening a new vista for the prevention and diagnosis of AA.

Type-2 immunity associated with type-1 related skin inflammatory diseases: friend or foe?

Chronic inflammatory skin diseases are multifactorial diseases that combine genetic predisposition, environmental triggers, and metabolic disturbances associated with abnormal immune responses. From an immunological perspective, the better understanding of their physiopathology has demonstrated a large complex network of immune cell subsets and related cytokines that interact with both epidermal and dermal cells. For example, in type-1-associated diseases such as alopecia areata, vitiligo, and localized scleroderma, recent evidence suggests the presence of a type-2 inflammation that is well known in atopic dermatitis. Whether this type-2 immune response has a protective or detrimental impact on the development and chronicity of these diseases remains to be fully elucidated, highlighting the need to better understand its involvement for the management of patients. This mini-review explores recent insights regarding the potential role of type-2-related immunity in alopecia areata, vitiligo, and localized scleroderma.

Deciphering the Complex Immunopathogenesis of Alopecia Areata

Alopecia areata (AA) is an autoimmune-mediated disorder in which the proximal hair follicle (HF) attack results in non-scarring partial to total scalp or body hair loss. Despite the growing knowledge about AA, its exact cause still needs to be understood. However, immunity and genetic factors are affirmed to be critical in AA development. While the genome-wide association studies proved the innate and acquired immunity involvement, AA mouse models implicated the IFN-γ- and cytotoxic CD8+ T-cell-mediated immune response as the main drivers of disease pathogenesis. The AA hair loss is caused by T-cell-mediated inflammation in the HF area, disturbing its function and disrupting the hair growth cycle without destroying the follicle. Thus, the loss of HF immune privilege, autoimmune HF destruction mediated by cytotoxic mechanisms, and the upregulation of inflammatory pathways play a crucial role. AA is associated with concurrent systemic and autoimmune disorders such as atopic dermatitis, vitiligo, psoriasis, and thyroiditis. Likewise, the patient's quality of life (QoL) is significantly impaired by morphologic disfigurement caused by the illness. The patients experience a negative impact on psychological well-being and self-esteem and may be more likely to suffer from psychiatric comorbidities. This manuscript aims to present the latest knowledge on the pathogenesis of AA, which involves genetic, epigenetic, immunological, and environmental factors, with a particular emphasis on immunopathogenesis.

Bilateral Association Between Atopic Dermatitis® and Alopecia Areata: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to explore the association between atopic Dermatitis® (AD) and alopecia areata (AA). A comprehensive search was conducted in PubMed, Embase, Cochrane, and Web of Science from the inception of each database to November 10, 2022 for relevant studies. As there is a potential bilateral association between the 2 diseases, we assessed the prevalence/incidence of AA in patients with AD and the prevalence/incidence of AD in patients with AA. A total of 29 studies involving 11,233,448 participants were included in this analysis. AA was the exposure factor in 23 studies, AD in 7 studies, and both in 1 study. The meta-analysis revealed that the prevalence of AD was 11.2% (7.7%-15.1%) in patients with AA, and the prevalence of AA was 3.2% (95% confidence interval [CI]: 0.0%-11.5%) in patients with AD. The incidence of AD in AA patients was found to vary with age (P = 0.07). Based on 7 studies, there was a significant association between AD and AA when AA was the exposure factor [odds ratio, OR, = 4.537 (95% CI: 2.409-8.544)]; based on 10 studies, there was also a significant association between AD and AA when AD was the exposure factor [OR = 2.643 (95% CI: 1.737-3.995)]. In conclusion, this meta-analysis demonstrated the 2-way association between AD and AA, providing a clinical reference for disease prevention and control.

European expert consensus statement on the systemic treatment of alopecia areata

Alopecia areata is an autoimmune form of non-scarring hair loss. It is usually characterized by limited areas of hair loss. However, the disease may progress to complete scalp and body hair loss (alopecia totalis, alopecia universalis). In patients with alopecia areata hair loss significantly impacts the quality of life. Children and adolescents with alopecia areata often experience bullying, including physical aggression. The disease severity evaluation tools used in clinical practice are: the Severity of Alopecia Tool (SALT) score and the Alopecia Areata Scale (AAS). A SALT score equal to or greater than 20 constitutes a commonly accepted indication for systemic therapy in alopecia areata. When using the AAS, moderate to severe alopecia areata should be considered a medical indication for systemic treatment. Currently, the only two EMA-approved medications for alopecia areata are baricitinib (JAK 1/2 inhibitor) for adults and ritlecitinib (JAK 3/TEC inhibitor) for individuals aged 12 and older. Both are EMA-approved for patients with severe alopecia areata. Other systemic medications used off-label in alopecia areata include glucocorticosteroids, cyclosporine, methotrexate and azathioprine. Oral minoxidil is considered an adjuvant therapy with limited data confirming its possible efficacy. This consensus statement is to outline a systemic treatment algorithm for alopecia areata, indications for systemic treatment, available therapeutic options, their efficacy and safety, as well as the duration of the therapy.

Epidemiology of alopecia areata and population-wide comorbidities in Germany: analysis of longitudinal claims data

BACKGROUND

Alopecia areata (AA) is a chronic, immune-mediated disease characterized by acute-onset hair loss. The hair loss can range from small, circumscribed hairless areas on the scalp to complete loss of hair on the head and body hair. However, data on the epidemiology of AA are limited. Current evaluations are lacking in Germany. The aim of this study was to evaluate the epidemiology and comorbidity of AA in Germany based on claims data.

METHODS

A representative 40% sample of all adults who were insured with a German statutory health insurance company (DAK-Gesundheit) between 2016 and 2020 was evaluated (n = 2.88 million). Based on at least one relevant outpatient or inpatient diagnosis of International Classification of Diseases (ICD)-10 L63, the annual AA prevalence and incidence (ICD-10 L63) were calculated for 2016 to 2020. Different case definitions were used for diagnosis validation. In addition, the occurrence of comorbidities in patients with AA was investigated.

RESULTS

In 2020, AA prevalence was 210 cases per 100 000 and incidence 72 cases per 100 000. Compared with persons without AA, those with AA significantly more often had atopic dermatitis [rate ratio (RR) 2.9], pruritus (RR 2.7), lupus erythematosus (RR 2.4), urticaria (RR 2.3) and psoriasis (RR 2.2). Women were affected slightly more often than men (0.2% vs. 0.1%). On a regional level, higher prevalence and incidence rates were found in Brandenburg (prevalence 332 cases per 100 000; incidence 116 cases per 100 000), Hesse (prevalence 344 cases per 100 000; incidence 124 cases per 100 000) and Mecklenburg-Western Pomerania (prevalence 303 cases per 100 000; incidence 111 per 100 000).

CONCLUSIONS

AA is a common immune-mediated skin condition with marked regional variations in Germany. For a complete understanding of epidemiology, complementary population-based studies including clinical characteristics of AA are useful.

Alopecia areata: What's new in the epidemiology, comorbidities, and pathogenesis?

BACKGROUND

Alopecia areata (AA) is a common, acquired, and nonscarring type of hair loss that affects people of every generation and is intractable in severe and relapsing cases. Patients with AA, especially those with greater scalp involvement, have poor health-related quality-of-life scores.

PURPOSE

Following our previous review article in the April 2017 issue of the Journal of Dermatological Science, we aim to provide a pair of review articles on recent progress in multidisciplinary approaches to AA.

MAIN FINDINGS

We found more than 1800 publications on AA from July 2016 to December 2022.

CONCLUSIONS

In this review, we focused on the latest information on the epidemiology, comorbidities, and pathogenesis of AA.

Comorbid Conditions Associated with Alopecia Areata: A Systematic Review and Meta-analysis

BACKGROUND

Alopecia areata (AA) is a complex autoimmune condition resulting in nonscarring hair loss. In recent years, many studies have provided new evidence on comorbid diseases present in patients with AA. However, some studies have conflicting results, and analyses conducting a comprehensive approach are lacking.

OBJECTIVE

The aim of our study was to provide an updated systematic review and meta-analysis of medical comorbidities associated with AA.

METHODS

We searched PubMed, Embase, and Web of Science for case-control, cross-sectional, and cohort studies investigating medical comorbidities in AA published from inception through 1 February 2023.

RESULTS

We screened 3428 abstracts and titles and reviewed 345 full text articles for eligibility. Ultimately, 102 studies were analyzed, comprising 680,823 patients with AA and 72,011,041 healthy controls. Almost all included studies (100 of 102 studies) were of satisfactory to high quality (Newcastle-Ottawa scale score ≥ 4). Among patients with AA, comorbidities with the highest odds ratios (OR) compared with healthy controls and data available from more than one study included vitamin D deficiency (OR 10.13, 95% CI 4.24-24.20), systemic lupus erythematous (OR 5.53, 95% CI 3.31-9.23), vitiligo (OR 5.30, 95% CI 1.86-15.10), metabolic syndrome (OR 5.03, 95% CI 4.18-6.06), and Hashimoto's thyroiditis (OR 4.31, 95% CI 2.51-7.40). AA may be a protective factor for certain disorders, for which the AA group had lower odds compared with healthy controls, such as irritable bowel syndrome (OR 0.38, 95% CI 0.14-0.99) and colorectal cancer (OR 0.61, 95% CI 0.42-0.89).

CONCLUSION

These findings corroborate and contextualize the risks across comorbidities for patients with AA. Further work should be done to identify the underlying pathophysiology and understand appropriate screening criteria.

Efficacy, safety, and Pharmacoeconomics of Three Common Strategies for Pediatric Alopecia Areata Patients: A Retrospective Cohort Study

Objective

To evaluate and explore the efficacy, safety, and pharmacoeconomics of three common strategies for pediatric alopecia areata.

Methods

Chinese pediatric alopecia areata patients meeting the criteria were included and divided into three groups based on the received treatments. The efficacy, adverse events and pharmacoeconomics of these treatments were retrospectively analyzed.

Results

Twenty-four pediatric AA patients were recruited in this study. 100% (12/12) of patients from the traditional group achieved SALT100. In the tofacitinib group, 40.0% (2/5) of patients achieved SALT50. 20.0% (1/5) of patients achieved SALT75 and 40.0% (2/5) of patients achieved SALT100. In the MN group, 42.86% (3/7) of patients were non-responders. 14.28 (1/7) of patients achieved SALT75 and 42.86% (3/7) of patients achieved SALT100. The adverse effects (AEs) were mild in all three groups, and none of the patients discontinued the treatments due to the AEs. Comparing the other two groups, the MN treatment would be more time-intensive and more expensive.

Conclusion

For newly diagnosed or naive pediatric patients, the traditional treatment was the first-line approach. For long-duration, severe and refractory patients, tofacitinib and microneedling can be alternative options.

Case report: Dupilumab therapy for alopecia areata in a 4-year-old patient resistant to baricitinib

Alopecia areata (AA) is a non-scarring hair loss disorder. Alopecia totalis (AT) and alopecia universalis (AU) are the severe subtypes of AA. Age of onset before 6 years of age, disease duration of more than 1 year, and extensive alopecia involving more than 50% of the scalp (including AT or AU) suggest a poorer prognosis. Topical corticosteroids are the preferred first-line treatment for pediatric AA. While some treatments, such as intralesional corticosteroids, systemic steroids, contact immunotherapy with squaric acid dibutyl ester, and JAK inhibitors, showed efficacy in adults with AA, their safety profiles limit their use in pediatric AA patients. Dupilumab is a biologic that effectively addresses the patho-physiology of Th2 allergic diseases, and treats atopic diseases by inhibiting the helper Th2 immune axis. AA has been reported to be significantly improved with dupilumab for atopic dermatitis (AD) in children and adults. We report hair regrowth over all of the scalp, eyebrows, and eyelashes after 10 months of dupilumab therapy in a 4-year-old AU patient resistant to baricitinib.

Allergen-specific immunotherapy improves alopecia totalis in a severe atopic dermatitis patient

House dust mite (HDM) is the most common allergen exacerbating atopic dermatitis (AD), and allergen-specific immunotherapy (AIT) using HDM exhibited significant improvements in previous studies. Alopecia can occur as a complication of AD. Alopecia totalis (AT), a severe form of alopecia areata (AA), does not respond well to treatment and the chance of full recovery is less than 10%. For extensive hair loss, topical immunotherapy such as diphenylcyclopropenone (DPCP) is used as the first-line treatment. However, since DPCP is a kind of contact allergen, it has the potential to exacerbate AD. A 38-year-old man with AD and AA visited our clinic with symptoms worsening from 3 months ago. Although taking oral methylprednisolone (8 mg/day) and cyclosporine (100 mg/day) for 3 months, he has lost over 90% of his hair and the Eczema Area and Severity Index (EASI) was 43. Total serum immunoglobulin E (IgE) levels were 4454 kU/L (normal <100 kU/L) and the specific IgE levels for Dermatophagoides pteronyssinus and Dermatophagoides farinae following ImmunoCAP® were 20.8 and 37.4 kU/L, respectively. This patient did not respond well to previous treatment and was reluctant to use long-term steroids, so subcutaneous AIT using HDM was administered along with oral cyclosporine (100 mg/day). Topical tacrolimus was also applied to the AD lesions throughout the body. To reduce itching, nonsedative antihistamines were used if necessary. Hair loss was almost completely improved 1 year after the AIT initiation and the skin lesions of AD also improved (EASI 2.4). The specific IgE levels for D. pteronyssinus and D. farinae were 3.73 and 7.16 kU/L, respectively. Herein, we report a patient with promising results following AIT for AT with severe AD. In severe alopecic patients with AD refractory to conventional treatment, including immunosuppressants, AIT could be considered as a treatment option.

Overview of alopecia areata for managed care and payer stakeholders in the United States

Alopecia areata (AA) is an autoimmune disease with a complex pathophysiology resulting in nonscarring hair loss in genetically susceptible individuals. We aim to provide health care decision makers an overview of the pathophysiology of AA, its causes and diagnosis, disease burden, costs, comorbidities, and information on current and emerging treatment options to help inform payer benefit design and prior authorization decisions. Literature searches for AA were conducted using PubMed between 2016 and 2022 inclusive, using search terms covering the causes and diagnosis of AA, pathophysiology, comorbidities, disease management, costs, and impact on quality of life (QoL). AA is a polygenic autoimmune disease that significantly impacts QoL. Patients with AA face economic burden and an increased prevalence of psychiatric disease, as well as numerous systemic comorbidities. AA is predominantly treated using corticosteroids, systemic immunosuppressants, and topical immunotherapy. Currently, there are limited data to reliably inform effective treatment decisions, particularly for patients with extensive disease. However, several novel therapies that specifically target the immunopathology of AA have emerged, including Janus kinase (JAK) 1/2 inhibitors such as baricitinib and deuruxolitinib, and the JAK3/tyrosine kinase expressed in hepatocellular carcinoma (TEC) family kinase inhibitor ritlecitinib. To support disease management, a disease severity classification tool, the Alopecia Areata Severity Scale, was recently developed that evaluates patients with AA holistically (extent of hair loss and other factors). AA is an autoimmune disease often associated with comorbidities and poor QoL, which poses a significant economic burden for payers and patients. Better treatments are needed for patients, and JAK inhibitors, among other approaches, may address this tremendous unmet medical need. DISCLOSURES: Dr King reports seats on advisory boards for and/or is a consultant and/or clinical trial investigator for AbbVie, Aclaris Therapeutics Inc, AltruBio Inc, Almirall, Arena Pharmaceuticals, Bioniz Therapeutics, Bristol Meyers Squibb, Concert Pharmaceuticals Inc, Dermavant Sciences Inc, Eli Lilly and Company, Equillium, Incyte Corp, Janssen Pharmaceuticals, LEO Pharma, Otsuka/Visterra Inc, Pfizer, Regeneron, Sanofi Genzyme, TWi Biotechnology Inc, and Viela Bio; and speakers bureaus for AbbVie, Incyte, LEO Pharma, Pfizer, Regeneron, and Sanofi Genzyme. Pezalla is a paid consultant to Pfizer for market access and payer strategy concerns; Fung, Tran, Bourret, Takiya, Peeples-Lamirande, and Napatalung are employees of Pfizer and hold stock in Pfizer. This article was funded by Pfizer.

Safety of Janus Kinase inhibitors in Patients with Alopecia Areata: A Systematic Review

BACKGROUND AND OBJECTIVES

Janus kinase (JAK) inhibitors are emerging as a therapeutic option for alopecia areata. The risk of potential adverse events is currently debated. In particular, several safety data for JAK inhibitors are extrapolated from a single study in elderly patients with rheumatoid arthritis treated with tofacitinib or adalimumab/etanercept as a comparator. The population of patients with alopecia areata is clinically and immunologically different from persons with rheumatoid arthritis and tumor necrosis factor (TNF) inhibitors are not effective in these patients. The objective of this systematic review was to analyze available data on the safety of various JAK inhibitors in patients with alopecia areata.

METHODS

The systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature review was performed by searching PubMed, Scopus and EBSCO databases with the last search on March 13, 2023.

RESULTS

In total, 36 studies were included. The frequency and odds ratio (OR) for most common adverse events versus placebo were: for baricitinib hypercholesterolemia (18.2% vs 10.5%, OR = 1.9) and headache (6.1% vs 5.1%, OR = 1.2), for brepocitinib elevated creatinine level (27.7% vs 4.3%, OR = 8.6) and acne (10.6% vs 4.3%, OR = 2.7), for ritlecitinib acne (10.4% vs 4.3%, OR = 2.6) and headache (12.5% vs 10.6%, OR = 1.2) and for deuruxolitinib headache (21.4% vs 9.1%, OR = 2.7) and acne (13.6% vs 4.5%, OR = 3.3). The respective numbers for upper respiratory infections were: baricitinib (7.3% vs 7.0%, OR = 1.0) and brepocitinib (23.4% vs 10.6%, OR = 2.6); for nasopharyngitis: ritlecitinib (12.5% vs 12.8%, OR = 1.0) and deuruxolitinib (14.6% vs 2.3%, OR = 7.3).

CONCLUSIONS

The most common side effects of JAK inhibitors in patients with alopecia areata were headache and acne. The OR for upper respiratory tract infections varied from over 7-fold increased to comparable to placebo. The risk of serious adverse events was not increased.

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.

Alopecia areata and risk of atopic and autoimmune conditions: population-based cohort study

BACKGROUND

Alopecia areata (AA) has features of both autoimmune and atopic pathogenesis, but information on the risk of people with AA developing autoimmune and atopic conditions is limited.

OBJECTIVE

To assess the prevalence and incidence of atopic and autoimmune conditions in people with AA.

METHODS

This was a population-based cohort study of 8051 adults with newly diagnosed AA (AA group) and 32 204 adults in the matched control group, using the UK Oxford-Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) network primary care database, 2009-2018 (trial registration number: NCT04239521). Baseline prevalence of common atopic and autoimmune conditions, and risk of new-onset atopic and autoimmune disease, were estimated.

RESULTS

Atopic and autoimmune conditions were more prevalent in the AA group than the control group (atopic 37.2% vs. 26.7%, autoimmune 11.5% vs. 7.9%). The AA group were 43% more likely to develop any new-onset atopic condition [adjusted hazard ratio (aHR) 1.43. 95% confidence interval (CI) 1.28-1.61] and 45% more likely to develop any autoimmune condition (aHR 1.45, 95% CI 1.28-1.66) compared with the control group. When examining individual conditions, the AA group were at increased risk of atopic dermatitis (aHR 1.91, 95% CI 1.67-2.19), allergic rhinitis (aHR 1.32, 95% CI 1.14-1.54), autoimmune hypothyroidism (aHR 1.65, 95% CI 1.35-2.02), systemic lupus erythematosus (aHR 4.51, 95% CI 1.88-10.82) and vitiligo (aHR 2.39, 95% CI 1.49-3.82). There was no evidence for a higher incidence of other conditions examined.

CONCLUSION

People with AA have an increased burden of atopic and autoimmune comorbidity. This supports previous work suggesting that both T helper cell (Th)1 and Th2 immune responses may be implicated in the pathogenesis of AA.

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.

Comorbidities of atopic dermatitis-what does the evidence say?

Atopic dermatitis (AD) is a common disease that is associated with atopic and nonatopic comorbidities. There has been a growing interest in this area of AD, because presence or risk of comorbidities can in many ways impact the management of patients with AD. Thus, some treatments for AD may improve its comorbidities as well, whereas others may increase their risk. In this review article, we discuss various comorbidities of AD mostly on the basis of the results of recent multiple systematic reviews and meta-analyses to update readers about this rapidly developing area of dermatology. We emphasize the important information provided by studies presenting both relative risk and absolute risk, and show that AD is associated with, among others, atopic comorbidities such as asthma, rhinitis, and food allergy, nonatopic comorbidities such as ocular, psychiatric, infectious, endocrine, autoimmune, and cardiovascular diseases, and certain cancers. Clinicians need to be aware of these and be cognizant about positive and negative effects of existing and new treatments for AD.

Translational impact of omics studies in alopecia areata: recent advances and future perspectives

INTRODUCTION

Alopecia areata (AA) is a non-scarring, hair loss disorder and a common autoimmune-mediated disease with an estimated lifetime risk of about 2%. To date, the treatment of AA is mainly based on suppression or stimulation of the immune response. Genomics and transcriptomics studies generated important insights into the underlying pathophysiology, enabled discovery of molecular disease signatures, which were used in some of the recent clinical trials to monitor drug response and substantiated the consideration of new therapeutic modalities for the treatment of AA such as abatacept, dupilumab, ustekinumab and Janus Kinase (JAK) inhibitors.

AREAS COVERED

In this review, genomics and transcriptomics studies in AA are discussed in detail with particular emphasis on their past and prospective translational impacts. Microbiome studies are also briefly introduced.

EXPERT OPINION

The generation of large datasets using the new high-throughput technologies has revolutionized medical research and AA has also benefited from the wave of omics studies. However, the limitations associated with JAK inhibitors and clinical heterogeneity in AA patients underscore the necessity for continuing omics research in AA for discovery of novel therapeutic modalities and development of clinical tools for precision medicine.

Phase 2a randomized clinical trial of dupilumab (anti-IL-4Rα) for alopecia areata patients

BACKGROUND

Treatments for alopecia areata (AA) patients with extensive scalp hair loss are limited, and recent evidence supports a role for type 2 T-cell (Th2)-immune response in AA. Dupilumab, a monoclonal antibody inhibiting Th2 signaling, approved for type 2 diseases including atopic dermatitis, was evaluated in AA patients.

METHODS

Alopecia areata patients with and without concomitant atopic dermatitis were randomized 2:1 to receive weekly subcutaneous dupilumab (300 mg) or placebo for 24 weeks, followed by another 24-week dupilumab open-label phase. The primary outcome was change from baseline in the Severity of Alopecia Tool (SALT) score at week 24; secondary outcomes included a range of measures of hair regrowth.

RESULTS

Forty and 20 patients were assigned to the dupilumab and placebo arms, respectively. At week 24, disease worsening was documented in the placebo arm, with a least-squares mean change in the SALT score of -6.5 (95% confidence-interval [CI], -10.4 to -2.6), versus a change of 2.2 (95% CI, -0.6 to 4.94) in the dupilumab arm (p < .05). After 48 weeks of dupilumab treatment, 32.5%, 22.5% and 15% of patients achieved SALT₃₀ /SALT₅₀ /SALT₇₅ improvement, respectively, while in patients with baseline IgE ≥ 200 IU/ml response rates increased to 53.8%, 46.2%, and 38.5%, respectively. Moreover, baseline IgE predicts treatment response with 83% accuracy. No new safety signals were detected.

CONCLUSIONS

This hypothesis-driven trial is the first to indicate the possible pathogenic role of the Th2 axis and Th2 targeting in AA patients. Patient selection based on baseline serum IgE levels may improve treatment results (Clinicaltrials.gov number, NCT03359356).

The current state of knowledge of the immune ecosystem in alopecia areata

Alopecia areata (AA) is an autoimmune disease that affects approximately 2% of the general population. Patients with AA most commonly present with one or more patches of hair loss on the scalp in defined circular areas. A fraction of patients progress to more severe forms of the disease, in some cases with involvement of all body surfaces. The healthy anagen stage hair follicle is considered an immune privileged site, described as an environment that suppresses inflammatory immune responses. However, in AA, this immune privileged state collapses and marks the hair follicle as a target for the immune system, resulting in peri- and intrafollicular infiltration by lymphocytes. The complexity of the inflammatory ecosystem of the immune response to the hair follicle, and the relationships between the cellular and soluble participants, in AA remains incompletely understood. Many studies have demonstrated the presence of various immune cells around diseased hair follicles; however, often little is known about their respective contributions to AA pathogenesis. Furthering our understanding of the mechanisms of disease in AA is essential for the novel identification of targeted therapeutics that are efficacious and have few unintended effects.

Alopecia areata - Current understanding and management

Alopecia areata (AA) is a chronic, immune-mediated disease characterized by acute or chronic non-scarring hair loss, with a heterogeneity in clinical manifestations ranging from patchy hair loss to complete scalp and body hair loss. An overview of the up-to-date pathophysiology and the underlying signaling pathways involved in AA together with diagnostic and therapeutic recommendations will be provided. Current treatments, including topical, systemic and injectable interventions show varying response and frequent relapses reflecting the unmet clinical need. Thus, the new emerging concepts and therapeutic approaches, including Janus kinase inhibitors are eagerly awaited. Traditional and emerging therapies of AA will be discussed, in order to provide physicians with guidance for AA management. Since the latter is so challenging and often tends to take a chronic course, it can have an enormous psychosocial burden on patients, compromising their quality of life and often causing depression and anxiety. Therefore, the psychosocial aspects of the disease need to be evaluated and addressed, in order to implement appropriate psychological support when needed.

Alopecia Areata: an Update on Etiopathogenesis, Diagnosis, and Management

Alopecia areata (AA) is a common chronic tissue-specific autoimmune disease, resulting in hair loss, that affects up to 2% of the general population. The exact pathobiology of AA has still remained elusive, while the common theory is the collapse of the immune privilege of the hair follicle caused by immunological mechanism. Multiple genetic and environment factors contribute to the pathogenesis of AA. There are several clinical treatments for AA, varying from one or multiple well-defined patches to more diffuse or total hair loss of the scalp (alopecia totalis) or hair loss of the entire body (alopecia universalis). The available treatments for AA, such as corticosteroids and other immunomodulators, minoxidil, and contact immunotherapy, are of limited efficacy with a high risk of adverse effects and high recurrence rates, especially for patients with severe AA. Recent insights into the pathogenesis of AA have led to the development of new treatment strategies, such as Janus kinase (JAK) inhibitors, biologics, and several small molecular agents. In addition, modern therapies for AA, including antihistamines, platelet-rich plasma (PRP) injection, and other novel therapies have been well explored. In this review, we discussed the recent advances in the pathogenesis, diagnosis, and treatment of AA.

Biologics for Treatment of Atopic Dermatitis: Current Status and Future Prospect

Atopic dermatitis (AD) is a common inflammatory skin disease characterized by intense pruritus and recurrent eczematous lesions that significantly impair quality of life. It is a heterogeneous disease affecting both children and adults. The treatment of moderate-to-severe forms of AD is challenging, as topical corticosteroids are often insufficient to achieve disease control or inappropriate and off-label use of immunosuppressants may have significant undesirable side effects. The development of targeted biologic therapies specifically for AD is thus highly desirable. Dupilumab is the only biologic therapy that is Food and Drug Administration approved for the treatment of moderate-to-severe AD in patients 6 years and older, with consistent long-term efficacy and safety trial data. In this article, we review the mechanisms, safety, and efficacy of dupilumab from recent clinical trials, and we review the current data, mechanism of action, clinical efficacy, and limitations of new biologics currently in phase 2 and 3 clinical trials (lebrikizumab, tralokinumab, nemolizumab, tezepelumab, and ISB 830).

EAACI Biologicals Guidelines-dupilumab for children and adults with moderate-to-severe atopic dermatitis

Atopic dermatitis imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of atopic dermatitis, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based), its cost-effectiveness and long-term safety. The EAACI Guidelines on the use of dupilumab in atopic dermatitis follow the GRADE approach in formulating recommendations for each outcome and age group. In addition, future approaches and research priorities are discussed.

Cross-sectional study of blood biomarkers of patients with moderate to severe alopecia areata reveals systemic immune and cardiovascular biomarker dysregulation

BACKGROUND

Although there is increased understanding of the alopecia areata (AA) pathogenesis based on studies in scalp tissues, little is known about its systemic profile.

OBJECTIVE

To evaluate the blood proteomic signature of AA and determine biomarkers associated with increased disease severity.

METHODS

In a cross-sectional study, we assessed 350 inflammatory and cardiovascular proteins using OLINK high-throughput proteomics in patients with moderate to severe AA (n = 35), as compared with healthy individuals (n = 36), patients with moderate to severe psoriasis (n = 19), and those with atopic dermatitis (n = 49).

RESULTS

Seventy-four proteins were significantly differentially expressed between AA and control individuals (false discovery rate, <.05) including innate immunity (interleukin [IL] 6/IL-8), T helper (Th) type 1 (interferon [IFN] γ/CXCL9/CXCL10/CXCL11), Th2 (CCL13/CCL17/CCL7), Th17 (CCL20/PI3/S100A12), and cardiovascular-risk proteins (OLR1/OSM/MPO/PRTN3). Eighty-six biomarkers correlated with AA clinical severity (P < .05), including Th1/Th2, and cardiovascular/atherosclerosis-related proteins, including SELP/PGLYRP1/MPO/IL-18/OSM (P < .05). Patients with AA totalis/universalis showed the highest systemic inflammatory tone, including cardiovascular risk biomarkers, compared to control individuals and even to patients with atopic dermatitis and those with psoriasis. The AA profile showed some Th1/Th2 differences in the setting of concomitant atopy.

LIMITATIONS

Our analysis was limited to 350 proteins.

CONCLUSION

This study defined the abnormalities of moderate to severe AA and associated circulatory biomarkers. It shows that AA has systemic immune, cardiovascular, and atherosclerosis biomarker dysregulation, suggesting the need for systemic treatment approaches.