Treatment of alopecia areata: “What is new on the horizon?”

Alopecia areata: review of epidemiology, pathophysiology, current treatments and nanoparticulate delivery system

Alopecia areata (AA) is a kind of alopecia that affects hair follicles and nails. It typically comes with round patches and is a type of nonscarring hair loss. Various therapies are accessible for the management and treatment of AA, including topical, systemic and injectable modalities. It is a very complex type of autoimmune disease and is identified as round patches of hair loss and may occur at any age. This review paper highlights the epidemiology, clinical features, pathogenesis and new treatment options for AA, with a specific emphasis on nanoparticulate drug-delivery systems. By exploring these innovative treatment approaches, researchers aim to enhance the effectiveness and targeted delivery of therapeutic agents, ultimately improving outcomes for individuals living with AA.

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.

Efficacy and predictive factors of cyclosporine A in alopecia areata: a systematic review with meta-analysis

INTRODUCTION

Drugs for alopecia areata (AA) can induce hair regrowth, but do not change the disease course. Dual properties of cyclosporine A (CsA) as hypetrichotic and immunosuppressive agent have encouraged use in AA. We aimed to determine the most meaningful efficacy of CsA and reveal features helping enhance its efficacy and reduce relapses.

METHOD

Efficacy of CsA and predictive factors were investigated. Cochrane, MEDLINE, Pubmed and Embase databases were searched.

RESULTS

2,189 papers were retrieved. Based on 344 patients, mean proportion of responders was 73%. CsA monotherapy showed proportion of hair regrowth of 66%, whereas CsA combined with systemic corticosteroids yielded 78%. Overall efficacy in studies with duration of CsA treatment <6 months was: 74% (53-88%), while in those with duration ≥6 months was: 73% (47-89%). Recurrence with CsA monotherapy was 55% (6-96%) whereas when CsA was combined with systemic corticosteroids it was 28% (6-72%).

CONCLUSION

CsA confers a favorable therapeutic effect and concomitant use of steroids slightly enhances efficacy, but it dramatically decreases relapses. Longer treatments seem to lead to less relapse likelihood, but daily dose does not influence recurrence. Optimal CsA dosage is 5 mg/kg/day in single therapy regimen, whereas it is 3 mg/kg/day in the steroid-associated regimen. KEY POINTSWhat is already known about this subject? Most treatments for alopecia areata have not been critically evaluated. Current outcomes about the efficacy and relapse rate of cyclosporine A (CsA) are inconsistent and predictive factors about the clinical response are lacking.What this study adds? CsA confers a favorable therapeutic hair regrowth. Longer treatment seems to lead to less likelihood of relapse of AA, but the daily dose does not exert any effect on the recurrence of the disease. The concomitant use of corticosteroids broadly decreases relapses, and it also enhances efficacy.Impact on clinical practice The combination with corticosteroids is the most predictive feature to prevent relapse of AA, followed by the duration of CsA therapy. The daily dose of CsA is the feature with the least or null impact on the clinical course of AA.

Alopecia Areata Progression Index, a Scoring System for Evaluating Overall Hair Loss Activity in Alopecia Areata Patients with Pigmented Hair: A Development and Reliability Assessment

BACKGROUND

No scoring systems to evaluate overall hair loss activity in alopecia areata (AA) have been established.

OBJECTIVE

We sought to develop a measurement tool (Alopecia Areata Progression Index, AAPI) for the evaluation of overall hair loss activity in AA patients with pigmented hair.

METHODS

The scalp surface area was divided into 4 quadrants. In each quadrant, hair loss activity was scored on the basis of the percentage of alopecic area, clinical findings associated with hair loss. The AAPI was measured in 17 patients with different severities of AA.

RESULTS

Interobserver and intraobserver reliabilities were assessed by 4 investigators. A significant correlation of the total AAPI was found among the 4 investigators. In addition, intraobserver reliability was excellent, and interobserver reliability was statistically reliable.

CONCLUSION

The AAPI seems to represent a system capable of truly quantifying overall hair loss activity in AA patients with different severity, demonstrating trustworthy interobserver and intraobserver reliability.

Serum level of interleukin-17A in patients with alopecia areata and its relationship to age

BACKGROUND

There is strong evidence for an autoimmune etiology of alopecia areata (AA). Interleukin-17A (IL-17A) is a Th17 proinflammatory cytokine that has been linked to the pathogeneses of diverse autoimmune and inflammatory diseases.

OBJECTIVES

This study aimed to measure serum IL-17A in AA patients and to study associations between IL-17A levels and AA severity, duration, and age of onset, and patient gender and age.

METHODS

The study enrolled 39 AA patients and 37 healthy control subjects. Scalp involvement was assessed using the Severity of Alopecia Tool (SALT), and clinical disease severity was determined. Serum IL-17A was measured using ELISAs.

RESULTS

Serum IL-17A was significantly higher in AA patients than in control subjects (P < 0.001). Correlations between serum IL-17A and gender, disease duration, SALT score, and disease severity were non-significant. Serum IL-17A was significantly higher in patients aged ≤30 years than in patients aged >30 years (P = 0.045). Age and serum IL-17A were significantly negatively correlated in patients with AA (rs = -0.363, P = 0.023) but not in control subjects (rs = -0.294, P = 0.077). Patients with juvenile-onset AA had significantly higher IL-17A levels than those with maturity-onset disease (P = 0.034). There was a significant negative correlation between age at disease onset and serum IL-17A (rs = -0.349, P = 0.029).

CONCLUSIONS

It is possible that IL-17A plays a role in the pathogenesis of AA. Serum IL-17A may be influenced by patient age and age of onset of AA but does not seem to influence disease severity.

Overview of alopecia areata

Alopecia areata is a complex genetic, immune-mediated disease that targets anagen hair follicles. The disease affects children and adults and is characterized by round or oval patches of hair loss, loss of all scalp hair (alopecia totalis), body hair (alopecia universalis), or ophiasis pattern hair loss. Patients may also present with patchy loss in multiple hair-bearing areas. Commonly associated diseases include asthma, allergic rhinitis, atopic dermatitis, thyroid disease, and automimmune diseases, such as thyroiditis and vitiligo. Nail abnormalities may precede, follow, or occur concurrently with hair loss activity. Alopecia areata has no known age, race, or ethnic preponderance and in contrast to other autoimmune diseases such as thyroiditis or lupus, the hair follicle does not usually sustain permanent injury and maintains its potential to regrow hair. It is estimated that alopecia areata affects between six and seven million individuals in the United States. Genes, the immune and nervous systems have all been implicated in the pathogenesis of alopecia areata. Although many treatments are available, there is still no cure. Bolstered by new scientific and translational opportunities from recently published genome-wide association studies, an ambitious treatment development program has recently been initiated by the National Alopecia Areata Foundation.

Alopecia areata: an evidence-based treatment update

BACKGROUND

There is no cure for alopecia areata, nor is there any universally proven therapy that induces and sustains remission. Treatment choices are frequently based on disease duration, extent, and activity as well as the age of the patient.

OBJECTIVE

Our objective was to review all randomized controlled studies on the treatment of alopecia areata.

METHODS

We performed a search in the biomedical literature database PubMed, and used the terms 'alopecia areata treatment' and article type 'randomized controlled trials'.

RESULTS

Following this algorithm, we reviewed, analyzed, and reported on 29 trials that examined the efficacy of anthralin, antidepressants, biologics, calcineurin inhibitors, corticosteroids (topical and systemic), minoxidil, prostaglandin analogs, sensitizers, and a miscellaneous group of topical and oral drugs with less scientific evidence (aromatherapy, photodynamic therapy, azelaic acid, garlic gel, bexarotene, triiodothyronine, inosiplex, and total glucosides of paeony).

CONCLUSION

Using the American College of Physicians Guideline grading system, our assessment is that the majority of published randomized controlled studies of alopecia areata are only of moderate quality. A number of treatments were found to be effective, for example, topical and oral corticosteroids and the sensitizing agents diphenylcyclopropenone and dinitrochlorobenzene; however, most studies had major limitations that hinder the interpretation of these results.

[Alopecia areata]

The epidemiology of alopecia areata as well as murine models of this disease and genome-wide association studies support the concept of alopecia areata as an autoimmune disease. In addition, the genome-wide association studies have led to the identification of new potential therapeutic targets such as CTLA4; these results have already led to the initiation of clinical studies, for example, with abatacept. Currently topical and intralesional corticosteroids as well as immunotherapy with diphenylcyclopropenone are most common therapeutic approaches.

What causes alopecia areata?

The pathobiology of alopecia areata (AA), one of the most frequent autoimmune diseases and a major unsolved clinical problem, has intrigued dermatologists, hair biologists and immunologists for decades. Simultaneously, both affected patients and the physicians who take care of them are increasingly frustrated that there is still no fully satisfactory treatment. Much of this frustration results from the fact that the pathobiology of AA remains unclear, and no single AA pathogenesis concept can claim to be universally accepted. In fact, some investigators still harbour doubts whether this even is an autoimmune disease, and the relative importance of CD8(+) T cells, CD4(+) T cells and NKGD2(+) NK or NKT cells and the exact role of genetic factors in AA pathogenesis remain bones of contention. Also, is AA one disease, a spectrum of distinct disease entities or only a response pattern of normal hair follicles to immunologically mediated damage? During the past decade, substantial progress has been made in basic AA-related research, in the development of new models for translationally relevant AA research and in the identification of new therapeutic agents and targets for future AA management. This calls for a re-evaluation and public debate of currently prevalent AA pathobiology concepts. The present Controversies feature takes on this challenge, hoping to attract more skin biologists, immunologists and professional autoimmunity experts to this biologically fascinating and clinically important model disease.

Treatment options for alopecia: an update, looking to the future

INTRODUCTION

Hair loss is a very common complaint. The diagnosis is based on clinical, dermoscopic and pathological examination. The treatment is usually continuous and requires strong compliance.

AREAS COVERED

This article aims to i) summarize current treatment options for the most common forms of hair loss; ii) update the literature on treatment options to emerge over the 3 years since the release of the first edition of this article in 2009; and iii) outline future strategies for treating alopecia.

EXPERT OPINION

There is good evidence-based information for the treatment of androgenetic alopecia. There are very few good-quality randomized studies, and no information about long-term results for most of the available treatments for alopecia areata and cicatricial alopecias. Significant research success has been achieved over the past few years through i) discovering the genetic profile of alopecia areata; ii) working on follicular neogenesis in androgenetic alopecia; and iii) discovering the PPAR-γ pathway in scarring alopecia.