Comparative Study of Efficacy and Safety of Topical Squaric Acid Dibutylester and Diphenylcyclopropenone for the Treatment of Alopecia Areata

Treatments for Moderate-to-Severe Alopecia Areata: A Systematic Narrative Review

Treatments for alopecia areata (AA) have traditionally been prescribed off-label, and there has been no universal agreement on how to best manage the condition. Baricitinib is the first oral selective Janus kinase (JAK) inhibitor approved for the treatment of adults with severe AA. As a better understanding of the evidence supporting the management of AA in clinical practice is needed, we conducted a systematic literature review and subsequent narrative review to describe available evidence pertaining to the efficacy and tolerability of treatments currently recommended for adults with moderate-to-severe forms of AA. From 2557 identified records, a total of 53 records were retained for data extraction: 9 reported data from 7 randomized controlled trials (RCTs) versus placebo, and 44 reported data from unique RCTs with no placebo arm, non-randomized trials, or observational studies. Across drug classes, data were reported heterogeneously, with little consistency of data collection or clinical endpoints used. The most robust evidence was for the JAK inhibitor class, in particular the JAK1/JAK2 inhibitor baricitinib. Five RCTs (three for baricitinib) demonstrated a consistent benefit of JAK inhibitor therapy over placebo across various clinical outcomes in adult patients with at least 50% scalp hair loss. Overall, hair regrowth varied widely for the other drug classes and was generally low for patients with moderate-to-severe AA. Relapses were commonly observed during treatment and upon discontinuation. Adverse effects were generally consistent with the known safety profile of each intervention. The heterogeneity observed prevented the conduct of a network meta-analysis or an indirect comparison of different treatments. We found that the current management of patients with moderate-to-severe AA often relies on the use of treatments that have not been well evaluated in clinical trials. The most robust evidence identified supported the use of baricitinib, and other oral JAK inhibitors, in patients with severe AA.

Treatments for alopecia areata: a network meta-analysis

BACKGROUND

Alopecia areata is an autoimmune disease leading to nonscarring hair loss on the scalp or body. There are different treatments including immunosuppressants, hair growth stimulants, and contact immunotherapy.

OBJECTIVES

To assess the benefits and harms of the treatments for alopecia areata (AA), alopecia totalis (AT), and alopecia universalis (AU) in children and adults.

SEARCH METHODS

The Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and WHO ICTRP were searched up to July 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that evaluated classical immunosuppressants, biologics, small molecule inhibitors, contact immunotherapy, hair growth stimulants, and other therapies in paediatric and adult populations with AA.

DATA COLLECTION AND ANALYSIS

We used the standard procedures expected by Cochrane including assessment of risks of bias using RoB2 and the certainty of the evidence using GRADE. The primary outcomes were short-term hair regrowth ≥ 75% (between 12 and 26 weeks of follow-up), and incidence of serious adverse events. The secondary outcomes were long-term hair regrowth ≥ 75% (greater than 26 weeks of follow-up) and health-related quality of life. We could not perform a network meta-analysis as very few trials compared the same treatments. We presented direct comparisons and made a narrative description of the findings.

MAIN RESULTS

We included 63 studies that tested 47 different treatments in 4817 randomised participants. All trials used a parallel-group design except one that used a cross-over design. The mean sample size was 78 participants. All trials recruited outpatients from dermatology clinics. Participants were between 2 and 74 years old. The trials included patients with AA (n = 25), AT (n = 1), AU (n = 1), mixed cases (n = 31), and unclear types of alopecia (n = 4). Thirty-three out of 63 studies (52.3%) reported the proportion of participants achieving short-term hair regrowth ≥ 75% (between 12 and 26 weeks). Forty-seven studies (74.6%) reported serious adverse events and only one study (1.5%) reported health-related quality of life. Five studies (7.9%) reported the proportion of participants with long-term hair regrowth ≥ 75% (greater than 26 weeks). Amongst the variety of interventions found, we prioritised some groups of interventions for their relevance to clinical practice: systemic therapies (classical immunosuppressants, biologics, and small molecule inhibitors), and local therapies (intralesional corticosteroids, topical small molecule inhibitors, contact immunotherapy, hair growth stimulants and cryotherapy). Considering only the prioritised interventions, 14 studies from 12 comparisons reported short-term hair regrowth ≥ 75% and 22 studies from 10 comparisons reported serious adverse events (18 reported zero events and 4 reported at least one). One study (1 comparison) reported quality of life, and two studies (1 comparison) reported long-term hair regrowth ≥ 75%. For the main outcome of short-term hair regrowth ≥ 75%, the evidence is very uncertain about the effect of oral prednisolone or cyclosporine versus placebo (RR 4.68, 95% CI 0.57 to 38.27; 79 participants; 2 studies; very low-certainty evidence), intralesional betamethasone or triamcinolone versus placebo (RR 13.84, 95% CI 0.87 to 219.76; 231 participants; 1 study; very low-certainty evidence), oral ruxolitinib versus oral tofacitinib (RR 1.08, 95% CI 0.77 to 1.52; 80 participants; 1 study; very low-certainty evidence), diphencyprone or squaric acid dibutil ester versus placebo (RR 1.16, 95% CI 0.79 to 1.71; 99 participants; 1 study; very-low-certainty evidence), diphencyprone or squaric acid dibutyl ester versus topical minoxidil (RR 1.16, 95% CI 0.79 to 1.71; 99 participants; 1 study; very low-certainty evidence), diphencyprone plus topical minoxidil versus diphencyprone (RR 0.67, 95% CI 0.13 to 3.44; 30 participants; 1 study; very low-certainty evidence), topical minoxidil 1% and 2% versus placebo (RR 2.31, 95% CI 1.34 to 3.96; 202 participants; 2 studies; very low-certainty evidence) and cryotherapy versus fractional CO2 laser (RR 0.31, 95% CI 0.11 to 0.86; 80 participants; 1 study; very low-certainty evidence). The evidence suggests oral betamethasone may increase short-term hair regrowth ≥ 75% compared to prednisolone or azathioprine (RR 1.67, 95% CI 0.96 to 2.88; 80 participants; 2 studies; low-certainty evidence). There may be little to no difference between subcutaneous dupilumab and placebo in short-term hair regrowth ≥ 75% (RR 3.59, 95% CI 0.19 to 66.22; 60 participants; 1 study; low-certainty evidence) as well as between topical ruxolitinib and placebo (RR 5.00, 95% CI 0.25 to 100.89; 78 participants; 1 study; low-certainty evidence). However, baricitinib results in an increase in short-term hair regrowth ≥ 75% when compared to placebo (RR 7.54, 95% CI 3.90 to 14.58; 1200 participants; 2 studies; high-certainty evidence). For the incidence of serious adverse events, the evidence is very uncertain about the effect of topical ruxolitinib versus placebo (RR 0.33, 95% CI 0.01 to 7.94; 78 participants; 1 study; very low-certainty evidence). Baricitinib and apremilast may result in little to no difference in the incidence of serious adverse events versus placebo (RR 1.47, 95% CI 0.60 to 3.60; 1224 participants; 3 studies; low-certainty evidence). The same result is observed for subcutaneous dupilumab compared to placebo (RR 1.54, 95% CI 0.07 to 36.11; 60 participants; 1 study; low-certainty evidence). For health-related quality of life, the evidence is very uncertain about the effect of oral cyclosporine compared to placebo (MD 0.01, 95% CI -0.04 to 0.07; very low-certainty evidence). Baricitinib results in an increase in long-term hair regrowth ≥ 75% compared to placebo (RR 8.49, 95% CI 4.70 to 15.34; 1200 participants; 2 studies; high-certainty evidence). Regarding the risk of bias, the most relevant issues were the lack of details about randomisation and allocation concealment, the limited efforts to keep patients and assessors unaware of the assigned intervention, and losses to follow-up.

AUTHORS' CONCLUSIONS

We found that treatment with baricitinib results in an increase in short- and long-term hair regrowth compared to placebo. Although we found inconclusive results for the risk of serious adverse effects with baricitinib, the reported small incidence of serious adverse events in the baricitinib arm should be balanced with the expected benefits. We also found that the impact of other treatments on hair regrowth is very uncertain. Evidence for health-related quality of life is still scant.

Guidelines for the Management of Patients with Alopecia Areata in Korea: Part I Topical and Device-based Treatment

BACKGROUND

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

OBJECTIVE

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

METHODS

We searched for relevant studies on the topical and device-based treatment of AA in the literature from inception until May 2021. 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 statements, and an agreement of 75% or greater was considered as consensus.

RESULTS

Currently, there remains a scarcity of topical treatments, which is supported by robust evidence from a number of high-quality randomized controlled trials. Current evidence supports the efficacy of topical corticosteroids, corticosteroid intralesional injection, and contact immunotherapy in AA patients. Topical corticosteroids and contact immunotherapy are recommended for pediatric AA. A consensus was achieved in 6 out of 14 (42.8%), and 1 out of 5 (20.0%) statements pertaining to topical and device-based treatments in AA, respectively. The expert consensus was from a single country, and the study may not cover all the treatments used.

CONCLUSION

The present study provides up-to-date, evidence-based treatment guidelines for AA based on the consensus reached among experts after considering regional healthcare circumstances, adding diversity to the previous guidelines.

Treatments for alopecia areata: A systematic review and network meta-analysis

Existing guidelines form no consensus for alopecia areata (AA) treatment due to the absence of a universal standard treatment and arbitrary selection of reference arms in randomized control trials (RCTs). The aim is to identify the best treatment and to rank treatments using systematic review and network meta-analysis. Data were extracted by the two investigators independently. Odds ratio (OR) of treatment success rate was pooled using the frequentist weighted least squares approach to random-model network meta-analysis. RCTs providing data of treatment success rate from PubMed, EMBASE, Web of Science, and manual search were included. About 54 RCTs consisting of 49 treatments and 3149 patients were included. Pentoxifylline plus topical corticosteroids had the highest treatment success rate compared with "no treatment," followed by pentoxifylline alone, topical calcipotriol plus narrowband ultraviolet radiation B phototherapy, topical calcipotriol, intralesional corticosteroids, systemic corticosteroids, minoxidil plus topical corticosteroids, topical bimatoprost, psoralen ultraviolet radiation A phototherapy, and tofacitinib. Even with the network meta-analysis, the best treatment because of independent loops and wide confidence intervals could not be identified. Treatment options above may be reasonable strategies, but further comparison is required.

Diphenylcyclopropenone plays an effective therapeutic role by up-regulating the TSLP/OX40L/IL-13 pathway in severe alopecia areata

Topical immunotherapy with diphenylcyclopropenone (DPCP) is considered to be the most effective treatment of severe AA. However, the mechanism is unclear and an early predictor for the efficacy needs to be explored. The TSLP/OX40L/IL-13 pathway is an important pathway to initiate and maintain Th2 immune responses. Our previous work suggests this pathway may play a role in severe AA treated with DPCP. Thus, to further investigate the mechanism of TSLP/OX40L/IL-13 pathway in severe AA treated with DPCP and explore the predictor for the efficacy of DPCP therapy, we conducted a prospective study to compare expression levels of TSLP, OX40L, Th2 cytokines IL-4, IL-5 and IL13, and Th1 cytokine IFN-γ in severe AA patients before and after the treatment. Results showed that 21 AA patients were responsive (responders) to the DPCP therapy and 12 were not responsive (non-responders). Responders had lower levels of TSLP, OX40L and IL-13 than non-responders before the treatment. After the DPCP treatment, TSLP, IL-5 and IL-13 increased and IFN-γ decreased in responders while there were no changes of TSLP, IL-4, IL-13 and IFN-γ in non-responders. Our data suggest that the TSLP/OX40L/IL-13 pathway is down-regulated in some severe AA patients and DPCP might play a therapeutic role by up-regulating the pathway in these severe AA patients. The TSLP/OX40L/IL-13 pathway could be a predictor of response to the DPCP therapy for severe AA patients.

Alopecia Areata: a Comprehensive Review of Pathogenesis and Management

Alopecia areata is a common hair loss condition that is characterized by acute onset of non-scarring hair loss in usually sharply defined areas ranging from small patches to extensive or less frequently diffuse involvement. Depending on its acuity and extent, hair loss is an important cause of anxiety and disability. The current understanding is that the condition represents an organ-specific autoimmune disease of the hair follicle with a genetic background. Genome-wide association studies provide evidence for the involvement of both innate and acquired immunity in the pathogenesis, and mechanistic studies in mouse models of alopecia areata have specifically implicated an IFN-γ-driven immune response, including IFNγ, IFNγ-induced chemokines and cytotoxic CD8 T cells as the main drivers of disease pathogenesis. A meta-analysis of published trials on treatment of alopecia areata states that only few treatments have been well evaluated in randomized trials. Nevertheless, depending on patient age, affected surface area and disease duration, an empiric treatment algorithm can be designed with corticosteroids and topical immunotherapy remaining the mainstay of therapy. The obviously limited success of evidence-based therapies points to a more important complexity of hair loss. At the same time, the complexity of pathogenesis offers opportunities for the development of novel targeted therapies. New treatment opportunities based on the results of genome-wide association studies that implicate T cell and natural killer cell activation pathways are paving the way to new approaches in future clinical trials. Currently, there are ongoing studies with the CTLA4-Ig fusion protein abatacept, anti-IL15Rβ monoclonal antibodies and the Janus kinase inhibitors tofacitinib, ruxolitinib and baricitinib. Ultimately, the options available for adapting to the disease rather than treating it in an effort to cure may also be taken into consideration in selected cases of long-standing or recurrent small spot disease.