Efficacy and safety of ritlecitinib in adults and adolescents with alopecia areata: a randomised, double-blind, multicentre, phase 2b-3 trial

A comprehensive review of small molecule drugs approved by the FDA in 2023: Advances and prospects

In 2023, the U.S. Food and Drug Administration has approved 55 novel medications, consisting of 17 biologics license applications and 38 new molecular entities. Although the biologics license applications including antibody and enzyme replacement therapy set a historical record, the new molecular entities comprising small molecule drugs, diagnostic agent, RNA interference therapy and biomacromolecular peptide still account for over 50 % of the newly approved medications. The novel and privileged scaffolds derived from drugs, active molecules and natural products are consistently associated with the discovery of new mechanisms, the expansion of clinical indications and the reduction of side effects. Moreover, the structural modifications based on the promising scaffolds can provide the clinical candidates with the improved biological activities, bypass the patent protection and greatly shorten the period of new drug discovery. Therefore, conducting an appraisal of drug approval experience and related information will expedite the identification of more potent drug molecules. In this review, we comprehensively summarized the pertinent information encompassing the clinical application, mechanism, elegant design and development processes of 28 small molecule drugs, and expected to provide the promising structural basis and design inspiration for pharmaceutical chemists.

Small molecule agents against alopecia: Potential targets and related pathways

Alopecia has emerged as a global concern, extending beyond the middle-aged and elderly population and increasingly affecting younger individuals. Despite its growing prevalence, the treatment options and effective drugs for alopecia remain limited due to the incomplete understanding of its underlying mechanisms. Therefore, it is urgent to explore the pathogenesis of alopecia and discover novel and safer therapeutic agents. This review provided an overview of the prevailing clinical disorders of alopecia, and the key pathways and targets involved in hair growth process. Additionally, it discusses FDA-approved drugs and clinical candidates for the treatment of alopecia, and explores small molecule compounds with anti-alopecia potential in the drug discovery phase. These endeavors are expected to provide researchers with valuable scientific insights and practical information for anti-alopecia drug discovery.

Efficacy and Tolerability of Brevilin-A, a Natural JAK Inhibitor, in Pediatric Alopecia Areata: A Case Series

Alopecia areata represents an autoimmune disease that specifically damages growing hair follicles on the scalp and/or around the body. Janus kinase inhibitors have been identified as an effective therapy in adult patients and topical formulations, such as Brevilin-A, might represent a well-tolerated treatment for mild-moderate disease in children and adolescents. The mechanism of action of Brevilin-A, a sesquiterpene lactone isolated from Centipeda minima, could consist in blocking STAT3 and STAT1 signaling as well as the JAKs activity by inhibiting the JAKs tyrosine kinase domain JH1. We report our cases of successful application of Brevilin-A in pediatric patients, suggesting this treatment as a safe and effective therapeutic option also for recalcitrant alopecia areata in pediatric population.

Infection risk with JAK inhibitors in dermatoses: a meta-analysis

Evolving evidence suggests that Janus Kinase Inhibitors (JAKi) may predispose to certain infections, including tuberculosis and human herpes viruses. This review aimed to compare the infection risk in patients on a systemic JAKi for a dermatologic indication to a placebo. A systematic review was carried out from inception to June 2023, using the EMBASE, Medline, SCOPUS, and Cochrane Library of Registered Trials databases. Eligible studies included placebo-controlled randomized trials that investigated the incidence of infection in patients with a dermatologic indication. Primary outcomes included the most commonly reported infections pertaining to serious and opportunistic infections, upper respiratory tract infections, nasopharyngitis, herpes simplex, varicella zoster, tuberculosis, neutropenia, and lymphopenia. A meta-analysis of incidence ratios was conducted to determine odds ratios (OR), with a 95% confidence interval (CI) analysis. The meta-analysis found no increased risk of serious (OR: 0.92, 95% CI: 0.61-1.43, P = 0.74) or opportunistic infections (OR: 0.65, 95% CI: 0.32-1.31, P = 0.23). The incidence of varicella-zoster infections was significantly higher in the JAKi cohort (OR: 1.72, 95% CI: 1.08-2.72, P = 0.022). From 25 studies, there was no overall increased risk of herpes simplex infections (OR: 1.43, 95% CI: 0.93-2.23, P = 0.102) to placebo; however, a significantly higher risk in those with atopic dermatitis to alopecia areata was demonstrated (OR: 1.73, 95% CI: 1.13-2.69, P = 0.013). The results of this analysis do not suggest an increased risk of serious and opportunistic infections in those on JAKi compared to placebo. However, they support an increased risk of varicella-zoster infections and a higher risk of herpes simplex infections in those with atopic dermatitis to alopecia areata. The results of this report support these agents' short-term safety but signal that vigilance should be practiced in patients at risk for serious or recurrent herpes virus infections.

Baricitinib Withdrawal and Retreatment in Patients With Severe Alopecia Areata: The BRAVE-AA1 Randomized Clinical Trial

Importance

Baricitinib has demonstrated efficacy for treating severe alopecia areata in adults. There is currently limited information about the need for continuous therapy after achieving scalp hair regrowth.

Objective

To report results from the randomized withdrawal period of the BRAVE-AA1 trial.

Design, Setting, and Participants

BRAVE-AA1 was a randomized, placebo-controlled, phase 3 randomized clinical trial with a treatment withdrawal substudy that was conducted at 70 centers in 3 countries beginning in March 2019. It included 654 adults with severe alopecia areata (AA) (Severity of Alopecia Tool [SALT] score ≥50) who were randomized 3:2:2 to receive treatment with baricitinib, 4 mg; baricitinib, 2 mg; or placebo. Data were analyzed in August 2023.

Intervention

At week 52, 154 patients who were responders (SALT score ≤20) were rerandomized 3:1 to continue to take their current dose of baricitinib or transition to placebo (randomized withdrawal). Responders randomized to placebo who experienced a loss of treatment benefit (>20-point worsening in SALT score) at any time after week 52 were retreated with their original baricitinib dose.

Main Outcome and Measures

The proportion of patients who lost treatment benefit through week 152 and the proportion of patients who recaptured response after retreatment. The last observation carried forward was used to impute missing or censored data.

Results

Of 654 patients who received treatment, the mean (SD) age was 37.1 (13.0) years, and there were 383 women (58.6%). At week 52, 10 of 39 responders taking baricitinib, 2 mg, and 30 of 115 responders taking baricitinib, 4 mg, were rerandomized to placebo. At 4 and 8 weeks of treatment withdrawal, 0% and 10% to 11% of patients, respectively, lost treatment benefit regardless of dose. At week 152, 80% of patients had lost benefit compared with 7% for those who continued baricitinib therapy for both dose groups. Within the follow-up observation periods, 5 of 8 patients taking 2 mg (63%) and 21 of 24 patients taking 4 mg (87.5%) recaptured a SALT score of 20 or less response after retreatment.

Conclusions and Relevance

Severe AA is a chronic, relapsing condition, and this randomized clinical trial found that withdrawal of therapy for a patient population with severe AA who had achieved meaningful hair regrowth after 1 year of treatment with baricitinib resulted in loss of benefit for almost all patients, indicating that continued therapy is required to maintain hair regrowth.

Trial Registration

ClinicalTrials.gov Identifier: NCT03570749.

Impact of Previous Alopecia Areata Treatment on Efficacy Responses up to Week 48 Following Ritlecitinib Treatment: A Post Hoc Analysis

INTRODUCTION

Patients with alopecia areata (AA) may have received several therapies for management of AA during their lives. In the ALLEGRO phase 2b/3 (NCT03732807) study, the oral JAK3/TEC family kinase inhibitor ritlecitinib demonstrated efficacy and an acceptable safety profile in patients aged ≥ 12 years with AA and ≥ 50% scalp hair loss. This post hoc analysis investigated associations between prior use of AA therapies and Severity of Alopecia Tool (SALT) responses in patients receiving ritlecitinib for AA.

METHODS

Patients receiving ritlecitinib 30 mg or 50 mg once daily with or without an initial 4-week 200-mg daily loading dose were grouped by previous exposure to AA treatments, including topicals, intralesional corticosteroids (ILCS), topical immunotherapy, and systemic immunosuppressants or any prior AA treatment. Multivariable logistic regression analyses evaluated the association between response based on a SALT score of ≤ 20 and any prior treatment for AA at weeks 24 and 48.

RESULTS

Of 522 patients, 360 (69.0%) had previous exposure to any AA treatment. At Week 24, SALT ≤ 20 response was positively associated with prior use of ILCS (odds ratio [OR], 2.12; 95% confidence interval [CI], 1.23-3.65; P < 0.05) and negatively associated with prior use of systemic immunosuppressants (OR 0.50; 95% CI 0.28-0.88; P < 0.05). Prior use of topicals or topical immunotherapy was not associated with SALT ≤ 20 response at Week 24. By Week 48, no association was identified between SALT ≤ 20 response and prior use of topicals, ILCS, topical immunosuppressants, or systemic immunosuppressants (all P > 0.05). Previous exposure to any AA therapy was not associated with SALT ≤ 20 response at weeks 24 or 48 (all P > 0.05).

CONCLUSIONS

Prior AA treatment history had no effect on longer-term treatment response to ritlecitinib.

TRIAL REGISTRATION NUMBER

NCT03732807.

JAK inhibitor selectivity: new opportunities, better drugs?

Cytokines function as communication tools of the immune system, serving critical functions in many biological responses and shaping the immune response. When cytokine production or their biological activity goes awry, the homeostatic balance of the immune response is altered, leading to the development of several pathologies such as autoimmune and inflammatory disorders. Cytokines bind to specific receptors on cells, triggering the activation of intracellular enzymes known as Janus kinases (JAKs). The JAK family comprises four members, JAK1, JAK2, JAK3 and tyrosine kinase 2, which are critical for intracellular cytokine signalling. Since the mid-2010s multiple JAK inhibitors have been approved for inflammatory and haematological indications. Currently, approved JAK inhibitors have demonstrated clinical efficacy; however, improved selectivity for specific JAKs is likely to enhance safety profiles, and different strategies have been used to accomplish enhanced JAK selectivity. In this update, we discuss the background of JAK inhibitors, current approved indications and adverse effects, along with new developments in this field. We address the issue of JAK selectivity and its relevance in terms of efficacy, and describe new modalities of JAK targeting, as well as new aspects of JAK inhibitor action.

[Janus kinase inhibitors for skin disorders]

Immune factors such as interferon‑ɣ and interleukin 4 belong to the group of cytokines that are dependent on type I/II receptors for their signal transmission. Upon activation, these receptors transmit their signal to the cell nucleus and, thus, modulate gene transcription via a signaling cascade consisting of Janus kinases (JAK). This family of four kinases (JAK 1, JAK 2, JAK 3, and tyrosine kinase 2 (TYK2)) subsequently activate members of the signal transducer and activator of transcription (STAT). This finding turned the JAK/STAT signaling pathway into a pharmacological target for the treatment of inflammatory diseases in which cytokines using type I/II receptors play a pathogenic role. In 2018, the European Medicines Agency (EMA) approved tofacitinib for the treatment of psoriatic arthritis. This was the first approval of a JAK/STAT pathway inhibitor for patients treated by dermatologists and rheumatologists. Since then, several new JAK inhibitors have been approved for dermatologic diseases such as atopic dermatitis, alopecia areata, vitiligo, and plaque-type psoriasis. In addition, JAK inhibitors are being investigated for the treatment of many other skin diseases. Thus, systemic JAK inhibitors complete the spectrum of immunotherapeutics with a broader immunological approach compared to monoclonal antibodies. The low molecular weight of JAK inhibitors enables the preparation of these drugs for both systemic and topical administration. Their utilization could represent a valuable alternative to topical steroids. The safety profile of JAK inhibitors must be taken into account. Possible long-term effects may become apparent in the next few years. This article describes both approved JAK inhibitors and relevant new JAK inhibitors that are promising candidates for approval as therapeutics in dermatology.

Efficacy and safety of ritlecitinib, an oral JAK3/TEC family kinase inhibitor, in adolescent and adult patients with alopecia totalis and alopecia universalis

This post-hoc analysis of the ALLEGRO phase 2b/3 study (NCT03732807) evaluated the efficacy and safety of ritlecitinib, an oral Janus kinase 3/TEC family kinase inhibitor, in patients with alopecia totalis (AT) and alopecia universalis (AU). Patients aged ≥ 12 years with alopecia areata (AA) and ≥50% scalp hair loss received once-daily ritlecitinib 50 or 30 mg (± 4-week 200-mg loading dose) or placebo for 24 weeks. In a subsequent 24-week extension period, the ritlecitinib groups continued their doses and patients initially assigned to placebo switched to ritlecitinib (200/50 or 50 mg daily). In this analysis, clinician- and patient-reported hair regrowth outcomes were assessed at weeks 24 and 48 in four AA subgroups: AT/AU, AT, AU, and non-AT/AU. Safety was monitored throughout. Of the 718 randomized patients, 151 (21%) and 147 (20%) were defined as having AT or AU, respectively. At week 24, Severity of Alopecia Tool (SALT) score ≤20 (≤20% scalp hair loss) response rates were higher in the ritlecitinib-treated AT/AU, AT, and AU groups (7%-14%, 7%-21%, and 4%-10%, respectively) vs the placebo group (0% in the AT/AU, AT, and AU groups). The proportions of patients with a SALT score of ≤20 increased through week 48 (AT/AU, 13%-31%; AT, 11%-27%; AU, 6%-41%). Additionally, at week 24, 25%-43%, 32%-42%, and 12%-50% of patients with AT/AU, AT, and AU, respectively, who received ritlecitinib achieved a moderately or greatly improved response based on the Patient Global Impression of Change scale. Response rates generally increased through week 48 and were similar across AA subgroups. In patients with AT/AU, ritlecitinib was well tolerated with a safety profile consistent with that of the overall AA population. Ritlecitinib demonstrated clinical efficacy, patient-reported improvement, and an acceptable safety profile in patients with AT and AU through week 48. A plain language summary of this study is available at https://doi.org/10.25454/pfizer.figshare.26879161. Clinicaltrials.gov: NCT03732807.

Hair regrowth in alopecia areata and re-pigmentation in vitiligo in response to treatment: Commonalities and differences

Both alopecia areata (AA) and vitiligo share common pathogenesis involving, interferon-γ (IFN-γ) and interleukin-15 (IL-15) signalling pathways that activate cytotoxic CD8+ T lymphocytes. These shared mechanisms may explain why both diseases respond to currently available treatments (e.g. topical/systemic corticosteroid) and emerging treatment modalities. As compared with the speed of re-pigmentation in vitiligo lesions, the regeneration of pigmented terminal hair follicles in AA lesions appears fast in response to treatments targeting the inhibition of the Janus kinases (JAKs) and other kinases. We summarize the commonalities and differences between AA and vitiligo focusing on the treatment modalities, followed by recent findings associated with hair follicle stem cells (HFSC) in hair bulge (HBg) and melanocyte stem cells (McSC) in HBg and hair germ (HGm). We then discuss how HFSC and HGm-McSC are involved in the initiation of anagen phase, followed by pigmented terminal hair regrowth in the recovering AA lesions in association with immunology. We also discuss how HBg-McSC contribute to the migration of fully dendritic mature melanocytes into interfollicular epidermis and the equal distribution of melanin in recovering vitiligo lesions. Finally, we present four hypotheses to elucidate the delayed distribution of melanin by mature melanocytes in depigmented vitiligo lesions from the aspects of stem cell biology, as compared with quick hair recovery in AA: (1) McSC are less abundant than HFSC. (2) McSC require a long travel, whereas HFSC reside close to hair regeneration trigger point. (3) Keratinocyte scaffold to accept melanin is not well preserved, whereas scaffold for hair regrowth is well preserved. (4) Inhibitors targeting JAKs and other kinases have less direct effects on melanocyte proliferation and differentiation in vitiligo than hair regrowth in AA. Our review provides an overview of treatment modalities and bridges the gap between scientific advancement and clinical practice in AA and vitiligo management.

Real-life effectiveness and safety of baricitinib in patients with severe alopecia areata: A 24-week Italian study

BACKGROUND

Alopecia areata is an autoimmune condition characterized by rapid hair loss in the scalp, eyebrows and eyelashes, for which treatments are limited. Baricitinib, an oral inhibitor of Janus kinases 1 and 2, has been recently approved to treat alopecia areata.

MATERIALS AND METHODS

We conducted a retrospective study involving 23 medical centres across Italy, enrolling patients affected by severe alopecia areata (SALT >50), for more than 6 months. Clinical and trichoscopic assessment was performed at each visit and impact on quality of life, anxiety and depression were evaluated using the Skindex-16 and the Hospital Anxiety and Depression Scale (HADS), respectively.

RESULTS

A total of 118 patients were enrolled, with a mean age of 39 years and a mean SALT >95. The mean value of the SALT score decreased from an average of 96.6 (±8.23 sd) to 48 (±35.2 sd) after 24 weeks of treatment and 42.3% of patients achieved a SALT 30, 31.3% a SALT 20 and 20.3% a SALT 10 by Week 24. Trichoscopic signs showed fewer yellow dots and black dots significantly earlier than hair regrowth. Adverse events during the treatment period (mild laboratory test abnormalities) were reported in 12.7% patients. No drop-out were registered.

CONCLUSION

Data on the effectiveness and safety of baricitinib are promising and support the use of this drug in severe forms of AA, also in the early stages. We also suggest performing trichoscopy in order to reveal early response to therapy.

Predictors and Management of Inadequate Response to JAK Inhibitors in Alopecia Areata

Alopecia areata is a common autoimmune disorder characterized by non-scarring hair loss on the scalp or other hair-bearing surface. In recent years, Janus kinase (JAK) inhibitors have shown promise in the treatment of alopecia areata by disrupting the signaling pathways involved in immune-mediated hair follicle damage. However, some patients with alopecia areata exhibit insufficient responses to JAK inhibitors. This review aims to explore the predictive factors for poor responses to JAK inhibitors in patients with alopecia areata and to discuss alternative treatment strategies in such cases. Patients with a longer duration of the current episode and higher baseline severity are at an increased risk of inadequate JAK inhibitor responses. Oral administration rather than topical application, and extended treatment durations, correlate with a favorable response. Notably, the poor response to JAK inhibitors in alopecia areata may be related to the amount and functional depletion of regulatory T cells resulting from an augmented T helper-2-type immune response. For patients with poor responses to JAK inhibitors, treatment adjustments may include increasing the dosage, extending the treatment duration, combination therapies, or switching to alternative JAK inhibitors. For patients with atopic comorbidities or psychological problems, it is important to select corresponding treatment options to optimize patient outcomes. Further research is needed to establish more reliable predictors and improve overall patient care.

A retrospective analysis of disease epidemiology, comorbidities, treatment patterns, and healthcare resource utilization of alopecia areata in the United Arab Emirates using claims database

Alopecia areata (AA) is an autoimmune disorder that manifests as nonscarring hair loss and imposes a substantial disease burden. The current study, using an e-claims database, assesses the disease burden, comorbidities, treatment patterns, specialties involved in the diagnosis of AA, healthcare resource utilization (HCRU), and associated costs in privately insured patients with AA in Dubai, United Arab Emirates. The retrospective longitudinal secondary study was conducted using Dubai Real-World Database e-claims data during 01 January 2014 to 30 June 2022. Patients with at least one diagnosis claim of AA during the index period (01 January 2015-30 June 2021) with continuous enrollment (one or more AA/non-AA claim in the post-index period) were included in the analysis. The patients were stratified into subcohorts based on diagnosis code and treatment patterns, as mild, moderate-to-severe, and others. Demographics, comorbidities, treatment patterns, specialists visited, and HCRU were assessed. The study included 11 851 patients with AA (mean age: mild: 37 years; moderate-to-severe: 36 years), with a male predominance (mild: 77.6%; moderate-to-severe: 60.8%). The most prevalent comorbidities in the moderate-to-severe AA subcohort were autoimmune and T-helper 2-mediated immune disorders, including contact dermatitis and eczema (62.1%), atopic dermatitis (36.1%), and asthma (36.1%). Most patients consulted dermatologists for treatment advice (mild AA: 87.4%; moderate-to-severe AA: 47.7%) and, notably, within 1 day of AA diagnosis. Topical steroids were frequently prescribed across cohorts, regardless of disease severity. Analysis of comorbidities among patients with AA indicated an additional HCRU burden among these subsets of patients. The median disease-specific HCRU cost was higher for psychological comorbidities versus autoimmune and T-helper 2-mediated immune disorders (US $224.99 vs US $103.70). There is a substantial disease and economic burden in patients with AA and associated comorbid conditions; therefore, investing in novel therapies that target the underlying autoimmune pathway may address the gap in effective management of AA.

Efficacy and safety of ritlecitinib in vitiligo patients across Fitzpatrick skin types with biomarker analyses

Efficacy and safety of ritlecitinib (an oral JAK3/TEC family kinase inhibitor) were evaluated in patients with nonsegmental vitiligo (NSV) across Fitzpatrick skin types (FSTs). Patients with FST I-III ('light skin'; n = 247) and FST IV-VI ('dark skin'; n = 117) received once-daily ritlecitinib 50 mg (with/without 4-week loading dose), low-dose ritlecitinib or placebo for 24 weeks. At baseline, patients with light skin displayed higher CLM-1 and NCR1 serum levels than patients with dark skin (p < 0.05). At 24 weeks, ritlecitinib 50 mg improved the extent of depigmentation measured by percent change from baseline in facial-vitiligo area scoring index (placebo-adjusted mean difference [90% CI]) in patients with light (-15.2 [-24.7, -5.8]; p = 0.004) and dark (-37.4 [-50.3, -24.4]; p < 0.0001) skin, with continuous re-pigmentation through week 48. Treatment-emergent adverse events were similar across FSTs. At weeks 4 and 24, ritlecitinib 50 mg reduced CXCL11 serum levels (p < 0.001) in patients with light skin, whereas patients with dark skin had increased levels at week 4 (p = 0.05) and no significant change at week 24. Ritlecitinib 50 mg decreased IL-9 and IL-22 expression levels in dark skin compared with light skin (qPCR; p < 0.05). These differences in immune dysregulations may explain why NSV patients with dark skin respond to therapy earlier than patients with light skin.

A phase 2a study investigating the effects of ritlecitinib on brainstem auditory evoked potentials and intraepidermal nerve fiber histology in adults with alopecia areata

Reversible axonal swelling and brainstem auditory evoked potential (BAEP) changes were observed in standard chronic (9-month) toxicology studies in dogs treated with ritlecitinib, an oral Janus kinase 3/tyrosine kinase expressed in hepatocellular carcinoma family kinase inhibitor, at exposures higher than the approved 50-mg human dose. To evaluate the clinical relevance of the dog toxicity finding, this phase 2a, double-blind study assessed BAEP changes and intraepidermal nerve fiber (IENF) histology in adults with alopecia areata treated with ritlecitinib. Patients were randomized to receive oral ritlecitinib 50 mg once daily (QD) with a 4-week loading dose of 200 mg QD or placebo for 9 months (placebo-controlled phase); they then entered the active-therapy extension and received ritlecitinib 50 mg QD (with a 4-week loading dose of 200 mg in patients switching from placebo). Among the 71 patients, no notable mean differences in change from baseline (CFB) in Waves I-V interwave latency (primary outcome) or Wave V amplitude on BAEP at a stimulus intensity of 80 dB nHL were observed in the ritlecitinib or placebo group at Month 9, with no notable differences in interwave latency or Wave V amplitude between groups. The CFB in mean or median IENF density and in percentage of IENFs with axonal swellings was minimal and similar between groups at Month 9. Ritlecitinib treatment was also not associated with an imbalanced incidence of neurological and audiological adverse events. These results provide evidence that the BAEP and axonal swelling finding in dogs are not clinically relevant in humans.

Comparative efficacy and safety of systemic steroids, oral JAK inhibitors and Contact Immunotherapy in the Treatment of severe alopecia areata: a systematic review and network meta-analysis

Severe alopecia areata (AA) is a nonscarring hair loss for immune disorder and SALT score ≥ 50%. The guidelines for managing patients with severe AA suggest treatments: systemic steroids, JAK inhibitors, and contact immunotherapy. However, there is a lack of evidence indicating the superiority of one treatment over another. Therefore, this study aimed to identify the most effective treatment for severe AA through network meta-analysis. Following the PRISMA guidelines, we conducted a network meta-analysis. The literature search was retrieved across four databases. The Cochrane 5.1 risk of bias assessment tool and ROBINS-I tool assessed quality of the included studies. Subsequently, efficacy and safety comparisons among the three treatments were conducted using Stata 14.0 on account of the frequency method. The SUCRA rank indicated that oral dexamethasone (95.9%) > diphenylcyclopropenone(DPCP) (74.5%) > oral ritlecitinib (62.6%) > oral baricitinib (46.9%) > squaric acid dibutyl ester(SADBE) (20.1%) > placebo (0.0%) from high to low in the aspect of improving efficacy. As for safety, placebo(88.4%) > oral ritlecitinib (86.5%) > oral baricitinib (62.1%) > SADBE (37.0%) > oral dexamethasone(22.3%) > DPCP(3.8%) in the aspect of decreasing adverse events. Oral dexamethasone and DPCP showed superior efficacy compared to oral ritlecitinib and oral baricitinib. However, in terms of safety, oral ritlecitinib was preferable. Some adverse events associated with oral dexamethasone and DPCP were intolerable to patients, whereas those related to oral ritlecitinib and oral baricitinib were more manageable. Overall, ritlecitinib and baricitinib remain promising drugs in the future treatment of severe AA.

Dupilumab induces hair regrowth in pediatric alopecia areata: a real-world, single-center observational study

Alopecia areata (AA) is nonscarring hair loss characterized by Th1 and concomitant Th2 skewing, particularly in atopic patients. Despite novel developments for adult AA, safe and effective treatments for pediatric patients remain limited. Dupilumab, with a well-studied safety profile, may have therapeutic potential for atopic pediatric AA. To evaluate the ability of dupilumab to regrow hair in pediatric AA patients. We conducted a single-center, retrospective, observational study to evaluate hair regrowth [using Severity of Alopecia Tool (SALT)] with dupilumab in 20 children with both AD and AA (age range 5-16 years, mean 10.8 years; baseline SALT range 3-100, mean 54.4). Patient demographics, atopic history, IgE and SALT scores were collected at 12wk follow-up visits, up to > 72wks, to evaluate hair regrowth. Spearman correlations with clinical data were performed. Patients showed clinical improvement over the follow-up period (range 24 to > 72wks, mean 67.6wks) with significant mean(± SD) reduction in SALT at 48wks versus baseline [20.4(± 35.1) vs 54.4(± 37.6), respectively; p < 0.01] and continued improvement up to > 72wks [2.2(± 4.9), p < 0.01]. Baseline SALT positively correlated with disease duration (r = 0.54, p < 0.01), and negatively correlated with improvement in SALT at weeks 24, 36, and 48 (|r|≥ 0.65, p < 0.01 for all comparisons). Baseline IgE positively correlated with improvement in SALT at week 36 (r > 0.60, p < 0.05). Dupilumab was well-tolerated, with no new safety concerns. These real-world data support the utility of dupilumab to safely treat pediatric AA patients, corroborating the role of Th2 skewing in children with AA and associated atopy, warranting larger clinical trials.

Efficacy and safety of deuruxolitinib, an oral selective Janus kinase inhibitor, in adults with alopecia areata: Results from the Phase 3 randomized, controlled trial (THRIVE-AA1)

BACKGROUND

Alopecia areata (AA) is a hair loss disorder that can seriously impact quality of life. Janus kinase (JAK) inhibitors, including deuruxolitinib, have previously demonstrated significant hair regrowth in AA.

OBJECTIVE

The Phase 3 THRIVE-AA1 randomized, double-blinded, placebo-controlled trial (NCT04518995) evaluated the safety and efficacy of the oral JAK1/JAK2 inhibitor deuruxolitinib in adult patients with AA.

METHODS

Patients aged 18-65 years with ≥50% hair loss were randomized to deuruxolitinib 8 mg twice daily, deuruxolitinib 12 mg twice daily, or placebo for 24 weeks. The primary end point was the percentage of patients achieving a Severity of Alopecia Tool score ≤20. A key secondary end point was the percentage of satisfaction of hair patient-reported outcome responders.

RESULTS

Significantly higher proportions of patients taking deuruxolitinib met the primary end point (8 mg 29.6%; 12 mg 41.5% versus placebo 0.8%). Both deuruxolitinib doses achieved significant improvements in all secondary end points versus placebo, including satisfaction of hair patient-reported outcome (8 mg 42.1%; 12 mg 53.0% versus placebo 4.7%). Most treatment-emergent adverse events were mild or moderate, consistent with other oral JAK inhibitors.

LIMITATIONS

Further studies are required to understand longer-term safety, efficacy, and impact of treatment cessation.

CONCLUSION

Both doses of deuruxolitinib were effective for hair regrowth. Patient satisfaction aligned with hair growth.

Ritlecitinib, a JAK3/TEC family kinase inhibitor, stabilizes active lesions and repigments stable lesions in vitiligo

The efficacy of ritlecitinib, an oral JAK3/TEC family kinase inhibitor, on active and stable lesions was evaluated in patients with active non-segmental vitiligo in a phase 2b trial (NCT03715829). Patients were randomized to placebo or daily ritlecitinib 50 mg (with or without 4-week 100-mg or 200-mg loading dose), 30 mg, or 10 mg for 24 weeks. Active lesions showed greater baseline expression of inflammatory/immune markers IFNG and CCL5, levels of CD103, and T-cell infiltrates than stable lesions. Patients with more active than stable vitiligo lesions showed higher baseline serum levels of CXCL9 and PD-L1, while patients with more stable than active lesions showed higher baseline serum levels of HO-1. At Week 24, ritlecitinib 50 mg significantly stabilized mean percent change from baseline in depigmentation extent in both active lesions and stable lesions vs. placebo-response, with stable lesions showing greater repigmentation. After 24 weeks of treatment, ritlecitinib 50 mg increased expression of melanocyte markers in stable lesions, while Th1/Th2-related and co-stimulatory molecules decreased significantly in both stable and active lesions. Serum from patients with more active than stable lesions showed decreased levels of ICOS and NK cell activation markers. These data, confirmed at transcription/protein levels, indicate that stable lesion repigmentation occurs early with ritlecitinib, while active lesions require stabilization of inflammation first. ClinicalTrials.gov: NCT03715829.

Delivery Strategies of siRNA Therapeutics for Hair Loss Therapy

Therapeutic needs for hair loss are intended to find small interfering ribonucleic acid (siRNA) therapeutics for breakthrough. Since naked siRNA is restricted to meet a druggable target in clinic,, delivery systems are indispensable to overcome intrinsic and pathophysiological barriers, enhancing targetability and persistency to ensure safety, efficacy, and effectiveness. Diverse carriers repurposed from small molecules to siRNA can be systematically or locally employed in hair loss therapy, followed by the adoption of new compositions associated with structural and environmental modification. The siRNA delivery systems have been extensively studied via conjugation or nanoparticle formulation to improve their fate in vitro and in vivo. In this review, we introduce clinically tunable siRNA delivery systems for hair loss based on design principles, after analyzing clinical trials in hair loss and currently approved siRNA therapeutics. We further discuss a strategic research framework for optimized siRNA delivery in hair loss from the scientific perspective of clinical translation.

Patient-Reported Satisfaction with Hair Regrowth in a Study of Ritlecitinib in Alopecia Areata: Results from ALLEGRO-2b/3

INTRODUCTION

Patients with alopecia areata (AA) report high levels of dissatisfaction with commonly used treatments. Patient-reported outcomes are essential to understanding patients' experiences with AA treatments. The objective of this study was to evaluate patient-reported satisfaction with hair growth among patients with AA receiving ritlecitinib or placebo and the correlation between clinician-assessed efficacy and patient-reported satisfaction.

METHODS

In the ALLEGRO-2b/3 (NCT03732807) trial, patients with AA and ≥50% scalp hair loss were randomized to daily ritlecitinib or placebo for 24 weeks, with a 24-week extension of continued ritlecitinib or switch from placebo to ritlecitinib. The Patient Satisfaction with Hair Growth (P-Sat) measure evaluated patients' satisfaction with hair growth in 3 domains: amount, quality, and overall satisfaction with hair growth. The prespecified analysis evaluated the proportion of patients who were slightly, moderately, or very satisfied with hair growth. Several post hoc analyses assessed the proportion of patients who were moderately/very satisfied and moderately/very dissatisfied and calculated polyserial correlations between change from baseline (CFB) in Severity of Alopecia Tool (SALT) and P-Sat scores at weeks 24 and 48.

RESULTS

At week 24, the proportion of patients (N = 718) reporting satisfaction (slightly, moderately, or very satisfied) overall with their hair growth ranged from 36.4% in the ritlecitinib 10-mg group (evaluated for dose ranging only) to 67.5% in the 200/50-mg group versus 22.6% in the placebo groups. In patients randomized to ritlecitinib, the proportion who were satisfied increased or was maintained at week 48. A substantially greater proportion of placebo patients who switched to ritlecitinib reported satisfaction at week 48 than at week 24. Similar results were observed for patient satisfaction with the amount and quality of hair growth. In the post hoc analyses defining satisfaction as moderately/very satisfied and dissatisfaction as moderately/very dissatisfied, the benefit of ritlecitinib was also observed. All P-Sat domain scores strongly correlated with CFB-SALT scores at weeks 24 (range 0.73-0.76; p < 0.05) and 48 (0.74-0.77; p < 0.05).

CONCLUSIONS

Patients receiving active ritlecitinib doses reported favorable results versus placebo in satisfaction with hair growth up to week 48. High concordance was observed between improvement in scalp hair growth evaluated by clinicians and patient-reported satisfaction.

A Review of JAK Inhibitors for Treatment of Alopecia Areata in the Military Health Care System

INTRODUCTION

Alopecia areata (AA) is a disease that manifests as patchy hair loss on the scalp and other parts of the body; severe disease may result in disfigurement, functional impairment, and significant psychological distress. This condition is understood to be caused by autoimmunity to the hair follicle and subsequent arrest of hair growth. New medications, baricitinib and ritlecitinib, belong to the Janus kinase (JAK) inhibitor family and are among the first FDA-approved treatments for severe AA. In this manuscript, we aim to answer the question: What treatment options exist for AA in the military health care system (MHS)? In doing so, we review the pathogenesis, physical and psychosocial impact of AA, conventional treatment of AA, and the efficacy and safety of baricitinib and ritlecitinib.

METHODS

A literature search was performed using PubMed, Embase, and Ovid for the history and pathogenesis of AA, psychosocial impact of disease, functional impairments, and current treatments. Keywords "alopecia areata," "current therapy for alopecia areata," "pathogenesis alopecia areata," "baricitinib," "ritlecitinib," "JAK inhibitor alopecia," "JAK inhibitor safety," "baricitinib efficacy," "alopecia eyelash," "alopecia nails," and "psychosocial impact of alopecia" were used for the search. The TRICARE manual was searched for guidelines applicable to the treatment of AA, DoD Instruction 6130.03 Volume 2 for medical standards for military service, and the U.S. Central Command Modification 15 for fitness of deployment to Central Command area of operations.

RESULTS

Traditional treatments such as intralesional steroids may be effective for some patients, but difficulty lies in controlling extensive or refractory disease. Janus kinase inhibitors, baricitinib and ritlecitinib, are found effective at improving severe refractory disease; baricitinib induced hair regrowth in 32.6% more patients than placebo, and ritlecitinib was found to be superior to placebo by at least 24%. Currently, there is no coverage for therapeutic treatment of hair growth in the MHS. Additionally, military members are disqualified for continued service if they require immunomodulator medications such as baricitinib and ritlecitinib. Those on immunomodulators are unable to deploy worldwide.

CONCLUSIONS

Baricitinib and ritlecitinib are effective treatments for widespread, progressive, and refractory AA. Although JAK inhibitors demonstrate improved effectiveness compared to non-immunomodulator treatments, their use in the MHS for this purpose is limited.

Alopecia Areata of the Nails: Diagnosis and Management

Background: Alopecia areata (AA) is a common form of non-scarring alopecia characterized by acute hair loss. Nail involvement, though not always present, can occur in AA patients. Nail changes are more frequent in severe forms of AA and in children. Methods: Literature related to nail changes in AA was comprehensively reviewed after a search on the PubMed database without time restrictions in order to identify common clinical presentations and associated factors to aid clinicians with the correct evaluation and management of these dystrophies. Results: Nail changes in AA include pitting, trachyonychia, leukonychia, red lunula, and miscellaneous alterations such as longitudinal ridging and brittle nails. Nail changes are usually asymptomatic but, nevertheless, sometimes cosmetically disfiguring and can be associated with a reduced quality of life and impaired daily activities. Conclusions: Nail changes in AA may precede or follow hair loss and can occur as an isolated finding. Diagnosis may require a biopsy for definitive identification. Spontaneous improvement is possible, particularly in children, and treatment is not always necessary. Further research is, however, needed to establish a consensus on treatment approaches according to age and severity.

Novel drugs approved by the EMA, the FDA, and the MHRA in 2023: A year in review

In 2023, seventy novel drugs received market authorization for the first time in either Europe (by the EMA and the MHRA) or in the United States (by the FDA). Confirming a steady recent trend, more than half of these drugs target rare diseases or intractable forms of cancer. Thirty drugs are categorized as "first-in-class" (FIC), illustrating the quality of research and innovation that drives new chemical entity discovery and development. We succinctly describe the mechanism of action of most of these FIC drugs and discuss the therapeutic areas covered, as well as the chemical category to which these drugs belong. The 2023 novel drug list also demonstrates an unabated emphasis on polypeptides (recombinant proteins and antibodies), Advanced Therapy Medicinal Products (gene and cell therapies) and RNA therapeutics, including the first-ever approval of a CRISPR-Cas9-based gene-editing cell therapy.

Estimation of health utility values for alopecia areata

PURPOSE

Alopecia areata (AA) is an autoimmune-mediated inflammatory dermatological disease characterised by non-scarring hair loss affecting the scalp and sometimes other hair-bearing sites. This study aimed to elicit health state utility values (HSUVs) from the UK general population for AA using time trade off (TTO) interviews.

METHODS

Vignette descriptions of health states defined by the extent of hair loss were developed (as well as one describing caregiver burden). These were developed using data from standardised patient reported outcome (PRO) measures, a literature review and qualitative interviews. Health states were defined based on the severity of alopecia tool (SALT), which assesses extensiveness of scalp hair loss. HSUVs were then elicited for each health state in TTO interviews with the UK public.

RESULTS

One caregiver and five patient health states were developed based on the literature review findings, clinical trial PRO (Hospital Anxiety and Depression Scale and Alopecia Areata Patient Priority Outcomes Questionnaire) data and qualitative interviews with patients (N = 11), clinical experts (N = 4) and caregivers of adolescents with AA (N = 10). These data showed a more severe impact among patients with more extensive hair loss. One hundred and twenty participants evaluated the vignettes in TTO interviews. Patient HSUVs ranged from 0.502 for the most extensive hair loss health state (SALT 50-100 + eyebrow and eyelash loss) to 0.919 (SALT 0-10) for the mildest health state. The caregiver HSUV was 0.882.

CONCLUSION

Quantitative and qualitative data sources were used to develop and validate vignettes describing different AA health states. Patient and caregiver HSUVs demonstrate a large impact associated with AA, especially for states defined by more extensive hair loss.

A year in pharmacology: new drugs approved by the US Food and Drug Administration in 2023

With 54 new drugs and seven cellular and gene therapy products, the approvals by the US Food and Drug Administration (FDA) recovered 2023 from the 2022 dent back to the levels of 2020-2021. As in previous years of this annual review, we assign these new drugs to one of three levels of innovation: first drug against a condition ("first-in-indication"), first drug using a novel molecular mechanism ("first-in-class"), and "next-in-class," i.e., a drug using an already exploited molecular mechanism. We identify four (7%) "first-in-indication," 22 (36%) "first-in-class," and 35 (57%) "next-in-class" drugs. By treatment area, rare diseases (54%) and cancer drugs (23%) were once again the most prevalent (and partly overlapping) therapeutic areas. Other continuing trends were the use of accelerated regulatory approval pathways and the reliance on biopharmaceuticals (biologics). 2023 marks the approval of a first therapy based on CRISPR/Cas9 gene editing.

Treatment Options for Alopecia Areata in Children and Adolescents

Alopecia areata (AA) lifetime incidence is around 2%, with many patients first experiencing symptoms during childhood. However, ritlecitinib is the only FDA-approved treatment for pediatric patients 12 years and older. This review outlines reported topical, injectable, and oral treatment options for pediatric patients with AA. Clinical studies were obtained via a PubMed search using the following search terms: alopecia areata, areata, universalis, or totalis and medication, therapy, treatment, drug, or management. Only studies with pediatric patients were included in this review. Commonly used therapies, including corticosteroids, methotrexate, and minoxidil, newer promising medications, such as Janus kinase inhibitors, and less frequently used topical and systemic treatments are included. A summary of the drug development pipeline and ongoing interventional clinical trials with pediatric patients is provided. Treatments demonstrate variable efficacy, and many patients require combination therapy for maximal response. More robust clinical data is needed for many of the medications reviewed in order to provide better care for these patients.

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.

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].

Abrocitinib Improved Dupilumab-Resistant Severe Atopic Dermatitis with Comorbid Mild Alopecia Areata in a 12-Year-Old Boy: A Case Report with 1-Year Follow-Up

Atopic dermatitis (AD) may sometimes be comorbid with alopecia areata (AA). However, traditional treatments for AA show limited efficacy. New treatment options, such as dupilumab and Janus kinase inhibitors, have proven efficacy in addressing both AD and AA. This article highlights the challenging case of a 12-year-old boy experiencing severe refractory AD and comorbid AA treated with oral abrocitinib after dupilumab failure with 1-year follow-up. After 3 months of treatment, his skin manifestations improved and the hair completely regenerated. No adverse reactions were observed during the 1-year follow-up period. This case provides evidence of the efficacy and safety of using abrocitinib to treat pediatric patients with both AD and AA.

The Epidemiology of Hospital-Treated Alopecia Areata in Denmark, 1995-2016

INTRODUCTION

Alopecia areata (AA) is an autoimmune skin disease presenting as nonscarring hair loss. Information on the epidemiology of AA, especially the occurrence of AA and its subtypes within the general population, is scarce. The study aimed to estimate the incidence rates and prevalence of hospital-treated AA and its subtypes in Denmark and to examine the demographic and clinical characteristics of patients with AA, including comorbidities and use of prescription medications.

METHODS

This was a cohort study based on data from administrative and health registers in Denmark in 1995-2016. The study included individuals who were (1) registered with a hospital inpatient or hospital-based outpatient clinic diagnosis of AA between 1995 and 2016 in the Danish National Patient Registry covering encounters at all Danish hospitals, (2) alive and resided in Denmark anytime between 1995 and 2016, (3) aged ≥ 12 years, and (4) resided uninterrupted in Denmark during the 12 months before the first AA diagnosis during the study period.

RESULTS

During the study period, 2778 individuals with an incident hospital-based diagnosis of AA were identified; 63.1% were female and 28.7% of the patients were aged ≥ 50 years. Over the study period, the overall incidence rate for any hospital-treated AA per 100,000 person-years was 2.62 (95% confidence interval [CI], 2.53-2.72), and the overall prevalence in 2016 was 71.7 (95% CI 69.4-74.1) per 100,000 persons. Both incidence rate and prevalence increased over time. Prevalence of most hospital-treated comorbidities or history of medication use was below 10% and was similar in the alopecia totalis (AT)/alopecia universalis (AU) and non-AT/AU subtypes of AA.

CONCLUSION

This cohort study reported incidence rates and prevalence over time and characteristics of individuals with hospital-treated AA in Denmark, which are in agreement with those previously reported in this population.

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.

Precision Dermatology: A Review of Molecular Biomarkers and Personalized Therapies

The evolution of personalized medicine in dermatology signifies a transformative shift towards individualized treatments, driven by the integration of biomarkers. These molecular indicators serve beyond diagnostics, offering insights into disease staging, prognosis, and therapeutic monitoring. Specific criteria guide biomarker selection, ensuring attributes like specificity, sensitivity, cost feasibility, stability, rapid detection, and reproducibility. This literature review, based on data from PubMed, SCOPUS, and Web of Science, explores biomarkers in Hidradenitis Suppurativa (HS), Psoriasis, Atopic Dermatitis (AD), Alopecia Areata (AA), Vitiligo, and Chronic Spontaneous Urticaria (CSU). In HS, TNF-α, IL-1β, and MMPs serve as biomarkers, influencing targeted therapies like adalimumab and anakinra. Psoriasis involves biomarkers such as TNF-α, IL-23, and HLA genes, shaping treatments like IL23 and IL17 inhibitors. AD biomarkers include ECP, IL-4, IL-13, guiding therapies like dupilumab and tralokinumab. For AA, lipocalin-2, cytokines, and genetic polymorphisms inform JAK inhibitors' use. Vitiligo biomarkers range from cytokines to genetic markers like TYR, TYRP1, guiding treatments like JAK inhibitors. CSU biomarkers encompass IgE, cytokines, and autologous serum tests, influencing therapies like omalizumab and cyclosporine. Comparing conditions, common proinflammatory markers reveal limited specificity. While some biomarkers aid diagnosis and standard treatments, others hold more scientific than clinical value. Precision medicine, driven by biomarkers, has shown success in skin malignancies. Future directions involve AI-powered algorithms, nanotechnology, and multi-omics integration for personalized dermatological care.

Transcriptomics- and Genomics-Guided Drug Repurposing for the Treatment of Vesicular Hand Eczema

Vesicular hand eczema (VHE), a clinical subtype of hand eczema (HE), showed limited responsiveness to alitretinoin, the only approved systemic treatment for severe chronic HE. This emphasizes the need for alternative treatment approaches. Therefore, our study aimed to identify drug repurposing opportunities for VHE using transcriptomics and genomics data. We constructed a gene network by combining 52 differentially expressed genes (DEGs) from a VHE transcriptomics study with 3 quantitative trait locus (QTL) genes associated with HE. Through network analysis, clustering, and functional enrichment analyses, we investigated the underlying biological mechanisms of this network. Next, we leveraged drug-gene interactions and retrieved pharmaco-transcriptomics data from the DrugBank database to identify drug repurposing opportunities for (V)HE. We developed a drug ranking system, primarily based on efficacy, safety, and practical and pricing factors, to select the most promising drug repurposing candidates. Our results revealed that the (V)HE network comprised 78 genes that yielded several biological pathways underlying the disease. The drug-gene interaction search together with pharmaco-transcriptomics lookups revealed 123 unique drug repurposing opportunities. Based on our drug ranking system, our study identified the most promising drug repurposing opportunities (e.g., vitamin D analogues, retinoids, and immunomodulating drugs) that might be effective in treating (V)HE.

Integrated Safety Analysis of Ritlecitinib, an Oral JAK3/TEC Family Kinase Inhibitor, for the Treatment of Alopecia Areata from the ALLEGRO Clinical Trial Program

BACKGROUND

The ALLEGRO phase 2a and 2b/3 studies demonstrated that ritlecitinib, an oral JAK3/TEC family kinase inhibitor, is efficacious at doses of ≥ 30 mg in patients aged ≥ 12 years with alopecia areata (AA).

OBJECTIVE

The objective of this study was to evaluate the safety of ritlecitinib in an integrated analysis of four studies in AA.

METHODS

Two cohorts were analyzed: a placebo-controlled and an all-exposure cohort. Proportions and study size-adjusted incidence rates (IRs) of adverse events (AEs) of interest and laboratory abnormalities are reported.

RESULTS

In the placebo-controlled cohort (n = 881; median exposure: 169 days), the proportion of ritlecitinib-treated patients with AEs was 70.2-75.4% across doses versus 69.5% in the placebo group; serious AEs occurred in 0-3.2% versus 1.9% for the placebo. A total of 19 patients permanently discontinued due to AEs (5 while receiving the placebo). In the all-exposure cohort (n = 1294), median ritlecitinib exposure was 624 days [2091.7 total patient-years (PY)]. AEs were reported in 1094 patients (84.5%) and serious AEs in 57 (4.4%); 78 (6.0%) permanently discontinued due to AEs. The most common AEs were headache (17.7%; 11.9/100 PY), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive test (15.5%; 9.8/100 PY), and nasopharyngitis (12.4%; 8.2/100 PY). There were two deaths (breast cancer and acute respiratory failure/cardiorespiratory arrest). Proportions (IRs) were < 0.1% (0.05/100 PY) for opportunistic infections, 1.5% (0.9/100 PY) for herpes zoster, 0.5% (0.3/100 PY) for malignancies (excluding nonmelanoma skin cancer), and 0.2% (0.1/100 PY) for major adverse cardiovascular events.

CONCLUSIONS

Ritlecitinib is well tolerated with an acceptable safety profile up to 24 months in patients aged ≥ 12 years with AA (video abstract and graphical plain language summary available).

TRIAL REGISTRIES

ClinicalTrials.gov: NCT02974868 (date of registration: 11/29/2016), NCT04517864 (08/18/2020), NCT03732807 (11/07/2018), and NCT04006457 (07/05/2019).

Short-Term Cardiovascular Complications in Dermatology Patients Receiving JAK-STAT Inhibitors: A Meta-Analysis of Randomized Clinical Trials

Importance

Evolving evidence suggests that patients receiving Janus kinase-signal transducer and activator of transcription inhibitors (JAK-STATi) may be at higher risk of major adverse cardiovascular events (MACE) and venous thromboembolism (VTE). Most existing literature has focused on indications that may confer a higher MACE and VTE risk than that among patients with isolated dermatological indications.

Objective

To evaluate risk of MACE, VTE, serious adverse events (SAEs), and tolerability of systemic JAK-STATi compared with placebo, in those with a dermatologic indication.

Data Sources

A systematic review of the literature was carried out to June 2023, using databases Embase, MEDLINE, SCOPUS, Cochrane Library of Registered Trials, and registered Clinical Trials. The analysis was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. The analysis itself took place in June 2023.

Study Selection

Placebo-controlled randomized clinical trials that compared systemic JAK-STATi with placebo, and investigated the safety in patients with alopecia areata, psoriasis, vitiligo, atopic dermatitis, lichen planus or hidradenitis suppurativa.

Data Extraction and Synthesis

Study selection and data extraction by 2 authors working independently using a standardized template. Crude numbers for MACE, VTE, SAEs, and study discontinuation due to treatment emergent adverse events (TEAEs) were pooled and underwent meta-analysis.

Main Outcomes and Measures

Incidence of MACE, VTE, SAE, and study discontinuation due to TEAEs. Analysis of these values against person exposure years to determine the incidence rate (IR). Risk ratios (RRs) compared incidence rates among treatment and placebo comparator arms.

Results

Forty-five randomized clinical trials were eligible for inclusion, with 12 996 patients receiving active JAK-STATi therapy and 4925 allocated to placebo treatment. Meta-analysis found no significant increase in MACE (I2 = 0.00%; RR, 0.47; 95% CI, 0.28-0.80) or VTE (I2 = 0.00%; RR, 0.46; 95% CI, 0.26-0.80) between placebo and JAK-STATi comparator arms. There was also no significant difference in SAEs (I2 = 12.38%; RR, 0.92; 95% CI, 0.72-1.20) and discontinuations between JAK-STATi and placebo (I2 = 23.55%; RR, 0.94; 95% CI, 0.76-1.19).

Conclusions and Relevance

This meta-analysis did not identify a significant increase in the risk of MACE and VTE in dermatology patients receiving JAK-STATi for median duration of 16 weeks. The results of this review suggest there is insufficient evidence that JAK-STATi confer an increased risk of cardiovascular complications in dermatological patients, especially when used for short time frames.

Alopecia areata: What's new in the diagnosis and treatment with JAK inhibitors?

Alopecia areata (AA) affects individuals of all ages and is intractable in severe relapsing cases. Dermatologists and other healthcare providers should consider AA in the medical context and prioritize treatment. Several randomized controlled clinical studies on Janus kinase (JAK) inhibitors with different specificities for the treatment of AA are ongoing. These studies have encouraged us to appreciate the importance of a definitive diagnosis and accurate evaluation of AA before and during treatment. Following our previous review article in 2017, here we provide the second part of this two-review series on the recent progress in the multidisciplinary approaches to AA from more than 1800 articles published between July 2016 and December 2022. This review focuses on the evaluation, diagnosis, and treatment of AA. We also provide the latest information on the safety and efficacy of JAK inhibitors for the treatment of AA and describe their mechanisms of action.

Virtual Bioequivalence Assessment of Ritlecitinib Capsules with Incorporation of Observed Clinical Variability Using a Physiologically Based Pharmacokinetic Model

Ritlecitinib, an orally available Janus kinase 3 and tyrosine kinase inhibitor being developed for the treatment of alopecia areata (AA), is highly soluble across the physiological pH range at the therapeutic dose. As such, it is expected to dissolve rapidly in any in vitro dissolution conditions. However, in vitro dissolution data showed slower dissolution for 100-mg capsules, used for the clinical bioequivalence (BE) study, compared with proposed commercial 50-mg capsules. Hence, a biowaiver for the lower 50-mg strength using comparable multimedia dissolution based on the f2 similarity factor was not possible. The in vivo relevance of this observed in vitro dissolution profile was evaluated with a physiologically based pharmacokinetic (PBPK) model. This report describes the development, verification, and application of the ritlecitinib PBPK model to translate observed in vitro dissolution data to an in vivo PK profile for ritlecitinib capsule formulations. Virtual BE (VBE) trials were conducted using the Simcyp VBE module, including the model-predicted within-subject variability or intra-subject coefficient of variation (ICV). The results showed the predicted ICV was predicted to be smaller than observed clinical ICV, resulting in a more optimistic BE risk assessment. Additional VBE assessment was conducted by incorporating clinically observed ICV. The VBE trial results including clinically observed ICV demonstrated that proposed commercial 50-mg capsules vs clinical 100-mg capsules were bioequivalent, with > 90% probability of success. This study demonstrates a PBPK model-based biowaiver for a clinical BE study while introducing a novel method to integrate clinically observed ICV into VBE trials with PBPK models. Trial registration: NCT02309827, NCT02684760, NCT04004663, NCT04390776, NCT05040295, NCT05128058.

Target Occupancy and Functional Inhibition of JAK3 and TEC Family Kinases by Ritlecitinib in Healthy Adults: An Open-Label, Phase 1 Study

Ritlecitinib is a small molecule in clinical development that covalently and irreversibly inhibits Janus kinase 3 (JAK3) and the TEC family of kinases (BTK, BMX, ITK, TXK, and TEC). This phase 1, open-label, parallel-group study assessed target occupancy and functional effects of ritlecitinib on JAK3 and TEC family kinases in healthy participants aged 18-60 years who received 50 or 200 mg single doses of ritlecitinib on day 1. Blood samples to assess ritlecitinib pharmacokinetics, target occupancy, and pharmacodynamics were collected over 48 hours. Target occupancy was assessed using mass spectroscopy. Functional inhibition of JAK3-dependent signaling was measured by the inhibition of the phosphorylation of its downstream target signal transducer and activator of transcription 5 (pSTAT5), following activation by interleukin 15 (IL-15). The functional inhibition of Bruton's tyrosine kinase (BTK)-dependent signaling was measured by the reduction in the upregulation of cluster of differentiation 69 (CD69), an early marker of B-cell activation, following treatment with anti-immunoglobulin D. Eight participants received one 50 mg ritlecitinib dose and 8 participants received one 200 mg dose. Ritlecitinib plasma exposure increased in an approximately dose-proportional manner from 50 to 200 mg. The maximal median JAK3 target occupancy was 72% for 50 mg and 64% for 200 mg. Ritlecitinib 50 mg had >94% maximal target occupancy of all TEC kinases, except BMX (87%), and 200 mg had >97% for all TEC kinases. For BTK and TEC, ritlecitinib maintained high target occupancy throughout a period of 48 hours. Ritlecitinib reduced pSTAT5 levels following IL-15- and BTK-dependent signaling in a dose-dependent manner. These target occupancy and functional assays demonstrate the dual inhibition of the JAK3- and BTK-dependent pathways by ritlecitinib. Further studies are needed to understand the contribution to clinical effects of inhibiting these pathways.

Improvements in immune/melanocyte biomarkers with JAK3/TEC family kinase inhibitor ritlecitinib in vitiligo

BACKGROUND

Vitiligo is an autoimmune depigmenting disorder with no effective and safe treatments. Its pathogenesis is not fully elucidated.

OBJECTIVE

This substudy of a randomized, double-blind, placebo-controlled phase 2b trial (NCT03715829) evaluated effects of ritlecitinib, an oral JAK3/TEC family kinase inhibitor, on skin and blood biomarkers in participants with nonsegmental vitiligo (NSV).

METHODS

Sixty-five adults with NSV participated in the substudy and received daily treatment for 24 weeks with placebo (n = 14) or ritlecitinib with or without a 4-week loading dose: 200 (loading dose)/50 mg (n = 13), 100/50 mg (n = 12), 50 mg (n = 11), 30 mg (n = 8), or 10 mg (n = 6). Skin (lesional and nonlesional) biopsy samples were obtained at baseline and at 4 and 24 weeks. Changes from baseline to weeks 4 and 24 in skin and blood molecular and cellular biomarkers were evaluated by RNA sequencing, quantitative real-time PCR, proteomic analysis, and flow cytometry.

RESULTS

Ritlecitinib-treated groups showed downregulation of immune biomarkers and upregulation of melanocyte-related markers at weeks 4 and 24 compared to baseline and/or placebo. Significant reductions were seen in CD3+/CD8+ T-cell infiltrates, with significant increases in melanocyte markers (tyrosinase; Melan-A) in NSV lesions in the 50 mg ritlecitinib groups (both P < .05). There was significant, dose-dependent downregulation in T-cell activation, NK, cytotoxic, and regulatory markers in lesional skin (IL-2, IL2-RA, IL-15, CCR7, CD5, CRTAM, NCR1, XCL1, KIR3DL1, FASLG, KLRD; P < .05). TH1 and TH2 markers were also downregulated in lesional skin and blood in a dose-dependent manner (P < .05). Changes in immune biomarkers correlated with clinical response.

CONCLUSIONS

Ritlecitinib significantly downregulated proinflammatory biomarkers and increased melanocyte products in skin and blood of participants with NSV, suggesting its potential in treatment. Ritlecitinib-mediated changes positively correlated with clinical response.

Cardiovascular and Venous Thromboembolic Risk With JAK Inhibitors in Immune-Mediated Inflammatory Skin Diseases: A Systematic Review and Meta-Analysis

Importance

Janus kinase (JAK) inhibitors are an effective treatment option for patients with certain skin-related conditions, such as atopic dermatitis, alopecia areata, and vitiligo, but there is a current US Food and Drug Administration (FDA) boxed warning label for oral and topical JAK inhibitors regarding increased risk of major adverse cardiovascular events (MACE), venous thromboembolism (VTE), serious infections, malignant neoplasm, and death. However, this boxed warning was precipitated by results of the Oral Rheumatoid Arthritis Trial (ORAL) Surveillance study, which only included patients with rheumatoid arthritis, and the same association may not be observed in dermatologic conditions.

Objective

To determine the risk of all-cause mortality, MACE, and VTE with JAK inhibitors in patients with dermatologic conditions.

Data Sources

PubMed and ClinicalTrials.gov were searched from database inception to April 1, 2023.

Study Selection

This review included phase 3 randomized clinical trials with a placebo/active comparator group of JAK inhibitors used for a dermatologic indication with FDA approval or pending approval or with European Union or Japanese approval. Studies without a comparison group, case reports, observational studies, and review articles were excluded.

Data Extraction and Synthesis

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Adverse events using odds ratios (ORs) and 95% CIs were calculated using a random-effects model and the DerSimonian-Laird method. Studies were screened, data abstracted, and quality assessed by 2 independent authors. The protocol was prospectively registered with PROSPERO.

Main Outcomes and Measures

Primary outcomes were a composite of adjudicated MACE and all-cause mortality, and VTE.

Results

The analysis included 35 randomized clinical trials with 20 651 patients (mean [SD] age, 38.5 [10.1] years; male, 54%) and a mean (SD) follow-up time of 4.9 (2.68) months. Findings did not show a significant difference between JAK inhibitors and placebo/active comparator in composite MACE and all-cause mortality (OR, 0.83; 95% CI, 0.44-1.57) or VTE (OR, 0.52; 95% CI, 0.26-1.04).

Conclusions and Relevance

In this systematic review and meta-analysis, use of JAK inhibitors was not associated with increased risk of all-cause mortality, MACE, and VTE compared to the placebo/active comparator groups. Additional trials with long-term follow-up are needed to better understand the safety risks of JAK inhibitors used for dermatologic indications.

Novel Janus Kinase Inhibitors in the Treatment of Dermatologic Conditions

Janus kinase inhibitors, also known as JAK inhibitors, JAKinibs or JAKi, are a new group of disease-modifying drugs. They work by inhibiting enzymes involved in the transmission of information from receptors located in the cell membrane to the cell interior, specifically to the cell nucleus, thus disrupting the JAK-STAT pathway. This pathway plays a role in key cellular processes such as the immune response and cell growth. This feature is used in the treatment of patients with rheumatological, gastroenterological and hematological diseases. Recently, it has been discovered that JAK-STAT pathway inhibitors also show therapeutic potential against dermatological diseases such as atopic dermatitis, psoriasis, alopecia areata and acquired vitiligo. Studies are underway to use them in the treatment of several other dermatoses. Janus kinase inhibitors represent a promising class of drugs for the treatment of skin diseases refractory to conventional therapy. The purpose of this review is to summarize the latest knowledge on the use of JAKi in dermatological treatment.

Evolution of Ritlecitinib Population Pharmacokinetic Models During Clinical Drug Development

BACKGROUND

Ritlecitinib is an oral Janus kinase 3/tyrosine kinase expressed in hepatocellular carcinoma family inhibitor undergoing parallel clinical development for alopecia areata, vitiligo, ulcerative colitis, Crohn's disease, and rheumatoid arthritis.

OBJECTIVE

As studies read out simultaneously, strategic planning of population pharmacokinetic model development and evaluation is required to ensure timely decisions.

METHODS

Data from healthy participants and patients from 12 clinical trials between December 2014 and July 2021 were included: seven phase I studies in healthy participants and organ impairment, five phase II/III studies in patients with rheumatoid arthritis, ulcerative colitis, alopecia areata, and vitiligo. Population pharmacokinetic models consisted of stepwise procedures to accommodate data availability and the model's application to answering clinical development questions. At each iteration of the model update, parameters of the next model were re-estimated by leveraging previous information and new data.

RESULTS

Three model development lifecycle iterations of the ritlecitinib population pharmacokinetic model were conducted to support alopecia areata, vitiligo, and ulcerative colitis study readouts. Initial structural modeling based on healthy participant data (and some rheumatoid arthritis and alopecia areata data) in iteration 1 provided a platform for comprehensive covariate testing during iteration 2, and model evaluation and implementation of the frequentist prior approach in iteration 3. The final model was a two-compartment model with first-order absorption and direct-response non-stationary clearance and bioavailability driven by concentrations in the peripheral compartment.

CONCLUSIONS

The present approach demonstrated the evolution of three population pharmacokinetic models with accumulating data, addressed clinical drug development questions related to systemic exposures of ritlecitinib, and informed the approved product label.

CLINICAL TRIAL REGISTRATION

NCT02309827, NCT02684760, NCT02958865, NCT02969044, NCT03232905, NCT03732807, NCT04016077, NCT03715829, NCT04037865, NCT04004663, NCT04634565, NCT02974868.

Drug Survival and Long-term Outcome of Tofacitinib in Patients with Alopecia Areata: A Retrospective Study

Several non-randomized clinical trials and retrospective studies have demonstrated encouraging efficacy and well-tolerated safety of tofacitinib in the treatment of alopecia areata. However, there are scarce data on a large cohort of patients with alopecia areata in long-term real-world practice. This single-centre, retrospective, observational cohort study included 126 patients with alopecia areata treated with tofacitinib between February 2021 and December 2022. The aims of this study are to evaluate drug survival, effectiveness and safety of tofacitinib for treatment of alopecia areata, and to identify potential factors influencing long-term outcomes. Median duration of treatment was 23.00 (interquartile range (IQR) 15.00, 47.25) weeks. Median all-cause survival time of 126 patients treated with tofacitinib was 44 weeks (95% confidence interval (95% CI) 36.3, 51.7), and the all-cause drug retention rate at 12 weeks, 24 weeks and 48 weeks were 90.0%, 66.4% and 42.3%, respectively. The most common reason for discontinuation was complete remission/satisfaction. A total of 80 patients treated with tofacitinib for over 6 months were included in the efficacy analysis, the overall complete response rate at 24 weeks was 33.8% (27/80). No life-threatening serious adverse events occurred. Sex is an independent risk factor in predicting patient outcomes. This real-world study confirmed the high effectiveness and acceptable safety profile of tofacitinib in alopecia areata, with a satisfactory drug survival rate, and provides supporting data for the clinical application of tofacitinib in Chinese patients with alopecia areata.

Inhibition of T-cell activity in alopecia areata: recent developments and new directions

Alopecia areata (AA) is an autoimmune disease that has a complex underlying immunopathogenesis characterized by nonscarring hair loss ranging from small bald patches to complete loss of scalp, face, and/or body hair. Although the etiopathogenesis of AA has not yet been fully characterized, immune privilege collapse at the hair follicle (HF) followed by T-cell receptor recognition of exposed HF autoantigens by autoreactive cytotoxic CD8+ T cells is now understood to play a central role. Few treatment options are available, with the Janus kinase (JAK) 1/2 inhibitor baricitinib (2022) and the selective JAK3/tyrosine kinase expressed in hepatocellular carcinoma (TEC) inhibitor ritlecitinib (2023) being the only US Food and Drug Administration-approved systemic medications thus far for severe AA. Several other treatments are used off-label with limited efficacy and/or suboptimal safety and tolerability. With an increased understanding of the T-cell-mediated autoimmune and inflammatory pathogenesis of AA, additional therapeutic pathways beyond JAK inhibition are currently under investigation for the development of AA therapies. This narrative review presents a detailed overview about the role of T cells and T-cell-signaling pathways in the pathogenesis of AA, with a focus on those pathways targeted by drugs in clinical development for the treatment of AA. A detailed summary of new drugs targeting these pathways with expert commentary on future directions for AA drug development and the importance of targeting multiple T-cell-signaling pathways is also provided in this review.

Efficacy and safety of ritlecitinib in adolescents with alopecia areata: Results from the ALLEGRO phase 2b/3 randomized, double-blind, placebo-controlled trial

BACKGROUND/OBJECTIVES

This subgroup analysis of the ALLEGRO phase 2b/3 trial (NCT03732807) evaluated the efficacy and safety of ritlecitinib, an oral, selective dual JAK3/TEC family kinase inhibitor, for the treatment of alopecia areata (AA) in patients aged 12-17 years.

METHODS

In ALLEGRO-2b/3, patients aged ≥12 years with AA and ≥50% scalp hair loss received once-daily ritlecitinib 50 or 30 mg (±4-week 200-mg loading dose) or 10 mg or placebo for 24 weeks. In a subsequent 24-week extension period, ritlecitinib groups continued their doses, and patients initially assigned to placebo switched to 200/50 or 50 mg daily. Clinician- and patient-reported hair regrowth outcomes and safety were assessed.

RESULTS

In total, 105 adolescents were randomized. At Week 24, 17%-28% of adolescents achieved a Severity of Alopecia Tool (SALT) score ≤20 (≤20% scalp without hair) in the ritlecitinib 30 mg and higher treatment groups versus 0% for placebo. At Week 48, 25%-50% of patients had a SALT score ≤20 across ritlecitinib treatment groups (30 mg and higher). Adolescents reporting that their AA "moderately" or "greatly" improved were 45%-61% in the ritlecitinib groups (30 mg and higher) (vs. 10%-22% for placebo) at Week 24 and 44%-80% at Week 48. The most common adverse events in adolescents were headache, acne, and nasopharyngitis. No deaths, major adverse cardiovascular events, malignancies, pulmonary embolisms, opportunistic infections, or herpes zoster infections were reported.

CONCLUSION

Ritlecitinib treatment demonstrated clinician-reported efficacy, patient-reported improvement, and an acceptable safety profile through Week 48 in adolescents with AA with ≥50% scalp hair loss.

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.

Hair Loss Profiles and Ritlecitinib Efficacy in Patients with Alopecia Areata: Post Hoc Analysis of the ALLEGRO Phase 2b/3 Study

INTRODUCTION

Ritlecitinib demonstrated efficacy in patients with alopecia areata (AA) in the ALLEGRO phase 2b/3 study (NCT03732807). However, hair loss presentation may vary based on location (e.g., scalp, eyebrow/eyelash, body). Here, we sought to identify distinct hair loss profiles at baseline and evaluate whether they affected the efficacy of ritlecitinib.

METHODS

Patients with AA aged ≥ 12 years with ≥ 50% scalp hair loss were randomized to daily ritlecitinib 10 mg (assessed for dose ranging only), 30 or 50 mg (± 4-week, 200-mg loading dose), or placebo for 24 weeks. Latent class analysis (LCA) identified hair loss profiles based on four baseline measurements: clinician-reported extent of scalp (Severity of Alopecia Tool score), eyebrow hair loss, eyelash hair loss, and patient-reported body hair loss. Logistic regression evaluated ritlecitinib (50 and 30 mg) efficacy vs placebo using Patient Global Impression of Change (PGI-C) and Patient Satisfaction with Hair Growth (P-Sat; amount, quality, and overall satisfaction) responses at Week 24, adjusting for key covariates, including latent class membership.

RESULTS

LCA identified five latent classes: (1) primarily non-alopecia totalis (AT; complete loss of scalp hair); (2) non-AT with moderate non-scalp involvement; (3) extensive scalp, eyebrow, and eyelash involvement; (4) AT with moderate non-scalp involvement; and (5) primarily alopecia universalis (complete scalp, face, and body hair loss). Adjusting for latent class membership, patients receiving ritlecitinib 30 or 50 mg were significantly more likely to achieve PGI-C response (30 mg: odds ratio, 8.62 [95% confidence interval, 4.42-18.08]; 50 mg: 12.29 [6.29-25.85]) and P-Sat quality of hair regrowth (30 mg: 6.71 [3.53-13.51]; 50 mg: 8.17 [4.30-16.46]) vs placebo at Week 24. Results were similar for P-Sat overall satisfaction and amount of hair regrowth.

CONCLUSION

Distinct and clinically relevant hair loss profiles were identified in ALLEGRO-2b/3 participants. Ritlecitinib was efficacious compared with placebo, independent of hair loss profile at baseline.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03732807.