Efficacy and safety of crisaborole ointment, a novel, nonsteroidal phosphodiesterase 4 (PDE4) inhibitor for the topical treatment of atopic dermatitis (AD) in children and adults

Capturing patient-reported sleep disturbance in atopic dermatitis clinical trials

BACKGROUND

Patient-focused approaches to capturing day-to-day variability in sleep disturbance are needed to properly evaluate the sleep benefits of new treatments. Such approaches rely on patient-reported outcome (PRO) measures validated in the target patient population.

METHODS

Using atopic dermatitis (AD) as an example of a disease in which sleep is commonly disturbed, we developed a strategy for measuring sleep disturbance in AD trials. In developing this strategy, we conducted a targeted literature review and held concept elicitation interviews with adolescents and adults with AD. We subsequently identified potentially suitable PRO measures and cognitively debriefed them. Finally, we evaluated their psychometric properties using data from phase 2b (NCT03100344) and phase 3 (NCT03985943 and NCT03989349) clinical trials.

RESULTS

The literature review confirmed that sleep disturbance is a key impact of AD but failed to identify validated PRO measures for assessing fluctuations in sleep disturbance. Subsequent concept elicitation interviews confirmed the multidimensional nature of sleep disturbance in AD and supported use of a single-item measure to assess overall sleep disturbance severity, complemented by a diary to capture individual components of sleep disturbance. The single-item sleep disturbance numerical rating scale (SD NRS) and multi-item Subject Sleep Diary (SSD)-an AD-adapted version of the Consensus Sleep Diary-were identified as potentially suitable PRO measures. Cognitive debriefing of the SD NRS and SSD demonstrated their content validity and their understandability to patients. Psychometric analyses based on AD trial data showed that the SD NRS is a well-defined, reliable, and fit-for-purpose measure of sleep disturbance in adults with AD. Furthermore, the SD NRS correlated with many SSD sleep parameters, suggesting that most concepts from the SSD can be covered using the SD NRS.

CONCLUSIONS

Using these findings, we developed an approach for measuring sleep disturbance in AD trials. Subject to further research, the same approach could also be applied to future trials of other skin diseases where itch causes sleep disturbance.

Efficacy, Safety, and Long-Term Disease Control of Ruxolitinib Cream Among Adolescents with Atopic Dermatitis: Pooled Results from Two Randomized Phase 3 Studies

BACKGROUND

Atopic dermatitis (AD), a highly pruritic, inflammatory skin disease, affects approximately 7% of adolescents globally. A topical formulation of ruxolitinib, a Janus kinase (JAK) 1/JAK2 inhibitor, demonstrated safety and efficacy among adolescents/adults in two phase 3 studies (TRuE-AD1/TRuE-AD2).

OBJECTIVE

To describe safety and efficacy of 1.5% ruxolitinib cream versus vehicle and long-term disease control of ruxolitinib cream among adolescents aged 12-17 years from pooled phase 3 study data.

METHODS

Patients [≥ 12 years old with AD for ≥ 2 years, Investigator's Global Assessment score (IGA) 2/3, and 3-20% affected body surface area (BSA) at baseline] were randomized 2:2:1 to ruxolitinib cream (0.75%/1.5%) or vehicle for 8 weeks of continuous use followed by a long-term safety (LTS) period up to 52 weeks with as-needed use. Patients originally applying vehicle were rerandomized 1:1 to 0.75%/1.5% ruxolitinib cream. Efficacy measures at week 8 included IGA treatment success (IGA-TS; i.e., score of 0/1 with ≥ 2 grade improvement from baseline), ≥ 75% improvement in Eczema Area and Severity Index (EASI-75), and ≥ 4-point improvement in itch numerical rating scale (NRS4). Measures of disease control during the LTS period included IGA score of 0 (clear) or 1 (almost clear) and percentage affected BSA. Safety was assessed throughout the study.

RESULTS

Of 1249 randomized patients, 245 (19.6%) were aged 12-17 years. Of these, 45 patients were randomized to vehicle and 92 patients to 1.5% ruxolitinib cream. A total of 104/137 (75.9%) patients continued on 1.5% ruxolitinib cream in the LTS period [82/92 (89.1%) continued on 1.5% ruxolitinib cream; 22/45 (48.9%) patients on vehicle were reassigned to 1.5% ruxolitinib cream], and 83/104 (79.8%) of these patients completed the LTS period. At week 8, substantially more patients who applied 1.5% ruxolitinib cream versus vehicle achieved IGA-TS (50.6% versus 14.0%), EASI-75 (60.9% versus 34.9%), and NRS4 (52.1% versus 17.4%; P = 0.009). The mean (SD) reduction in itch NRS scores was significantly greater in patients applying 1.5% ruxolitinib cream versus vehicle from day 2 [- 0.9 (1.9) versus -0.2 (1.4); P = 0.03]. During the LTS period, mean (SD) trough steady-state ruxolitinib plasma concentrations at weeks 12/52 were 27.2 (55.7)/15.5 (31.5) nM. The percentage of patients achieving IGA score of 0 or 1 was sustained or further increased with 1.5% ruxolitinib cream; mean affected BSA was generally low (< 3%; i.e., mild disease). Through 52 weeks, application site reactions occurred in 1.8% of adolescent patients applying 1.5% ruxolitinib cream at any time; no patients had serious adverse events. There were no serious infections, malignancies, major adverse cardiovascular events, or thromboembolic events.

CONCLUSIONS

Meaningful anti-inflammatory and antipruritic effects were demonstrated with 1.5% ruxolitinib cream in the subset of adolescent patients with AD, comparable with those observed in the overall study population; long-term, as-needed use maintained disease control and was well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers NCT03745638 (registered 19 November 2018) and NCT03745651 (registered 19 November 2018).

Efficacy and safety of Ruxolitinib, Crisaborole, and Tapinarof for mild-to-moderate atopic dermatitis: a Bayesian network analysis of RCTs

Given the lack of head-to-head studies of novel non-steroidal molecule topical therapies in mild-to-moderate atopic dermatitis (AD), network meta-analyses (NMAs) can provide comparative efficacy and safety data for clinical decision-making. In this NMA, we performed a literature search until 01 March 2023 for eligible studies written in English using databases, including PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov. Only double-blind randomized clinical trials (RCTs) with topical Ruxolitinib, Crisaborole, or Tapinarof versus vehicle for patients with mild-to-moderate AD were included. Baseline and follow-up data were extracted. Efficacy was evaluated using Investigator's Global Assessment (IGA) achieving "clear" or "almost clear," with 2 points or more improvement from baseline at the end of treatment, referred to as "IGA success." For binary outcomes, we analyzed in random-effects Bayesian NMA consistency models to compare the efficacy of these 3 topical therapies by odds ratio (OR) with 95% credibility interval (CrI). Overall, 10 phase 2 or phase 3 RCTs were identified, which included 4010 patients with mild to moderate AD. Compared with the topical vehicle control, all these 3 treatments had higher response rate of "IGA success" at the end of trial (Ruxolitinib 1.5% b.i.d: OR, 11.94; 95%CrI, 6.28-23.15; Crisaborole 2% b.i.d: OR, 2.08; 95%CrI, 1.46-3.52; Tapinarof 1% b.i.d: OR, 2.64; 95%CrI, 0.75-9.70). Notably, Ruxolitinib 1.5% b.i.d. had the highest probability of achieving "IGA success" in ranking analysis (Rank 1, SUCRA = 0.75) and lower risk of AE (Rank 8, SUCRA = 0.22). Besides, there was no difference in treatment-related adverse events between 3 therapies. Heterogeneity was not significant across studies.

Atopic Dermatitis

Atopic dermatitis (AD) is a common, chronic relapsing, and remitting inflammatory skin disease that is characterized by erythematous, scaly, and pruritic lesions often located over the flexural surfaces. Treatment goals of AD include the reduction of itching and burning, as well as the reduction of skin changes. Treatment of AD includes emollients and skin care, topical therapies including topical corticosteroids and steroid-sparing therapies, systemic therapies, and phototherapy.

Improved patient- and caregiver-reported outcomes distinguish tacrolimus 0.03% from crisaborole in children with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic skin disease that affects 20% of children worldwide and is associated with low patient-reported quality of life (QoL). Crisaborole (CRIS) and tacrolimus 0.03% (TAC) are Food and Drug Administration (FDA)-approved topical treatments for mild to moderate AD with similar clinical efficacy. Utilization of patient-reported outcomes (PROs) may provide meaningful data on the impact of AD treatments on patients and caregivers. This study used PROs to monitor the impact of crisaborole (CRIS) and tacrolimus 0.03% (TAC) on children with mild/moderate atopic dermatitis (AD) and caregiver burden.

METHODS

This open-label study randomized 47 child-caregiver dyads to CRIS or TAC for 12 weeks. Disease severity, child quality of life (QoL), itch, pain interference, anxiety, depression, sleep, caregiver burden and caregiver QoL were assessed at baseline, 6 and 12 weeks.

RESULTS

A total of 36 dyads completed the study. Children (mean age = 8.0 ± 3.9 years) had mild baseline AD and were diverse by race (39% white; 36% Black) and gender (53% males). Caregivers were mostly female (78%; mean age = 37 ± 7.6 years). Both arms improved disease severity (Eczema Area and Severity Index) from baseline to 12 weeks (CRIS = -2.4 vs. TAC = -1.9). Within-arm analyses comparing baseline to 12 weeks revealed TAC, but not CRIS, improved all child and caregiver PROs except sleep (all p < 0.05).

CONCLUSIONS

Our results demonstrated that topical treatment for 12 weeks was more beneficial than 6 weeks, with TAC improving more PROs than CRIS. Future trials should implement PROs to fully understand the impact of AD treatments.

Biologic and small-molecule therapy for treating moderate to severe atopic dermatitis: Mechanistic considerations

Atopic dermatitis (AD) is a complex and heterogeneous skin disease for which achieving complete clinical clearance for most patients has proven challenging through single cytokine inhibition. Current studies integrate biomarkers and evaluate their role in AD, aiming to advance our understanding of the diverse molecular profiles implicated. Although traditionally characterized as a TH2-driven disease, extensive research has recently revealed the involvement of TH1, TH17, and TH22 immune pathways as well as the interplay of pivotal immune molecules, such as OX40, OX40 ligand (OX40L), thymic stromal lymphopoietin, and IL-33. This review explores the mechanistic effects of treatments for AD, focusing on mAbs and Janus kinase inhibitors. It describes how these treatments modulate immune pathways and examines their impact on key inflammatory and barrier biomarkers.

Precise recognition of benzonitrile derivatives with supramolecular macrocycle of phosphorylated cavitand by co-crystallization method

The importance of molecular docking in drug discovery lies in the precise recognition between potential drug compounds and their target receptors, which is generally based on the computational method. However, it will become quite interesting if the rigid cavity structure of supramolecular macrocycles can precisely recognize a series of guests with specific fragments by mimicking molecular docking through co-crystallization experiments. Herein, we report a phenylphosphine oxide-bridged aromatic supramolecular macrocycle, F[3]A1-[P(O)Ph]3, which precisely recognizes benzonitrile derivatives through non-covalent interactions to form key-lock complexes by co-crystallization method. A total of 15 various benzonitrile derivatives as guest molecules are specifically bound by F[3]A1-[P(O)Ph]3 in co-crystal structures, respectively. Notably, among them, crisaborole (anti-dermatitis) and alectinib (anti-cancer) with the benzonitrile fragment, which are two commercial drug molecules approved by the U.S. Food and Drug Administration (FDA), could also form a key-lock complex with F[3]A1-[P(O)Ph]3 in the crystal state, respectively.

Therapeutic perspectives on PDE4B inhibition in adipose tissue dysfunction and chronic liver injury

INTRODUCTION

Chronic liver disease (CLD) is a complex disease associated with profound dysfunction. Despite an incredible burden, the first and only pharmacotherapy for metabolic-associated steatohepatitis was only approved in March of this year, indicating a gap in the translation of preclinical studies. There is a body of preclinical work on the application of phosphodiesterase 4 inhibitors in CLD, none of these molecules have been successfully translated into clinical use.

AREAS COVERED

To design therapies to combat CLD, it is essential to consider the dysregulation of other tissues that contribute to its development and progression. As such, proper therapies must combat this throughout the body rather than focusing only on the liver. To detail this, literature characterizing the pathogenesis of CLD was pulled from PubMed, with a particular focus placed on the role of PDE4 in inflammation and metabolism. Then, the focus is shifted to detailing the available information on existing PDE4 inhibitors.

EXPERT OPINION

This review gives a brief overview of some of the pathologies of organ systems that are distinct from the liver but contribute to disease progression. The demonstrated efficacy of PDE4 inhibitors in other human inflammatory diseases should earn them further examination for the treatment of CLD.

PDE4 inhibitors: potential protective effects in inflammation and vascular diseases

Phosphodiesterase 4 (PDE4) inhibitors are effective therapeutic agents for various inflammatory diseases. Roflumilast, apremilast, and crisaborole have been developed and approved for the treatment of chronic obstructive pulmonary disease psoriatic arthritis, and atopic dermatitis. Inflammation underlies many vascular diseases, yet the role of PDE4 inhibitors in these diseases remains inadequately explored. This review elucidates the clinical applications and anti-inflammatory mechanisms of PDE4 inhibitors, as well as their potential protective effects on vascular diseases. Additionally, strategies to mitigate the adverse reactions of PDE4 inhibitors are discussed. This article emphasizes the need for further exploration of the therapeutic potential and clinical applications of PDE4 inhibitors in vascular diseases.

2% Crisaborole Ointment for the Treatment of Chronic Cheilitis Caused by Lip Tattoos

The increasing popularity of tattoo art, including facial cosmetic tattoos, has led to a growing societal acceptance of tattoos. However, complications such as lip inflammation following cosmetic lip tattoos remain a concern. This article presents the case of a 47-year-old Asian woman who experienced recurrent lip swelling, purulent discharge, and scarring after receiving lip tattoos. Despite previous treatment with corticosteroid injections yielding unsatisfactory results, the patient showed significant improvement with topical application of 2% Crisaborole, a phosphodiesterase-4 inhibitor. Crisaborole modulates intracellular cyclic adenosine monophosphate levels, thereby reducing tissue inflammation and swelling associated with chronic cheilitis. Additionally, pulse laser therapy was effective in addressing residual tattoo pigment and scar tissue. This case highlights the therapeutic challenges of managing chronic inflammatory diseases of the lips secondary to cosmetic tattoos and introduces Crisaborole as a promising treatment option, offering insights for managing similar conditions in the future.

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

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

PDE4D and miR-203 are promising biomarkers for canine atopic dermatitis

BACKGROUND

Canine atopic dermatitis (CAD) is a common genetically predisposed, inflammatory, and pruritic skin disorder that affects dogs globally. To date, there are no specific biomarkers available to diagnose CAD, and the current diagnosis is based on a combination of criteria including patient history, clinical signs, and exclusion of other relevant differential diagnoses.

METHODS AND RESULTS

We examined the gene expression of phosphodiesterase 4D (PDE4D) in peripheral blood mononuclear cells (PBMCs), as well as miR-203 and miR-483 in plasma, in three groups: healthy dogs, CAD dogs, and other inflammatory pruritic skin diseases (OIPSD) such as pemphigus foliaceus, scabies, cutaneous lymphoma, and dermatophytosis. Our results showed that PDE4D gene expression in the CAD group is statistically higher compared to those in the healthy and OIPSD groups, suggesting PDE4D may be a specific marker for CAD. Nevertheless, no correlation was found between PDE4D gene expression levels and the lesion severity gauged by CAD severity index-4 (CADESI-4). We also showed that miR-203 is a generic marker for clinical dermatitis and differentiates both CAD and OIPSD inflammatory conditions from healthy controls.

CONCLUSIONS

We show that PDE4D is a potential marker to differentiate CAD from non-atopic healthy and OIPSD while miR-203 may be a potential marker for general dermatologic inflammation. Future study of PDE4D and miR-203 on a larger scale is warranted.

Master protocols and other innovative trial designs in inflammation and immunology to expedite clinical drug development

Master protocol designs, such as umbrella and basket studies, allow multiple compounds or multiple target populations to be evaluated simultaneously within a single protocol, and have been widely adopted in oncology clinical trials. These novel designs can also be applied in other therapeutic areas, where they could have several benefits over conducting traditional randomized controlled trials. Here, we detail Pfizer's recent implementations of master protocol designs in inflammation and immunology clinical studies, focusing on the opportunities for cost and resource savings and how these designs can expedite the time required to bring new treatments to patients in need.

Efficacy and safety of crisaborole ointment, 2%, in participants aged ≥45 years with stasis dermatitis: Results from a fully decentralized, randomized, proof-of-concept phase 2a study

BACKGROUND

Crisaborole ointment, 2%, is a nonsteroidal topical phosphodiesterase 4 inhibitor approved for the treatment of mild-to-moderate atopic dermatitis.

OBJECTIVE

To evaluate the efficacy and safety of crisaborole in stasis dermatitis (SD).

METHODS

In this randomized, double-blind, vehicle-controlled, decentralized phase 2a study (NCT04091087), 65 participants aged ≥45 years with SD without active ulceration received crisaborole or vehicle (1:1) twice-daily for 6 weeks. The primary end point was percentage change from baseline in total sign score at week 6 based on in-person assessment.

RESULTS

Crisaborole-treated participants had significantly reduced total sign score from baseline versus vehicle based on in-person (nondermatologist) assessment (-32.4% vs -18.1%, P = .0299) and central reader (dermatologists) assessment of photographs (-52.5% vs -10.3%, P = .0004). Efficacy according to success and improvement per Investigator's Global Assessment score and lesional percentage body surface area reached statistical significance based on central reader but not in-person assessments. Skin and subcutaneous tissue disorders were common all-causality treatment-emergent adverse events with crisaborole.

LIMITATIONS

Small sample size and short treatment duration were key limitations. In-person assessment was not conducted by dermatologists.

CONCLUSION

Crisaborole improved signs and symptoms of SD and was well tolerated. Central reader assessment represents a promising approach for siteless clinical research.

Efficacy and Safety of Crisaborole Ointment 2% in Chinese Patients Aged ≥ 2 Years with Mild to Moderate Atopic Dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic immuno-inflammatory skin disease. Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor approved for the treatment of mild to moderate AD. This post hoc analysis assesses the efficacy and safety of crisaborole in Chinese patients aged ≥ 2 years with mild to moderate AD.

METHODS

We evaluated the efficacy and safety of crisaborole in Chinese patients from the vehicle-controlled, phase 3 CrisADe CLEAR study. Patients were randomly assigned 2:1 to receive crisaborole or vehicle twice daily, respectively, for 28 days. The primary endpoint was percent change from baseline in Eczema Area and Severity Index (EASI) total score at day 29. Key secondary endpoints were improvement in Investigator's Static Global Assessment (ISGA), ISGA success, and change from baseline in weekly average Peak Pruritus Numerical Rating Scale (PP-NRS) score. Adverse events were documented.

RESULTS

Of 391 patients in the overall study, 237 were from China, 157 assigned to crisaborole and 80 assigned to vehicle. A greater reduction in percent change from baseline in EASI total score at day 29 was shown in the crisaborole vs. vehicle group (least squares mean [LSM]: -66.34 [95% (confidence interval) CI -71.55 to -61.12] vs. -50.18 [95% CI -58.02 to -42.34]). Response rates for achievement of ISGA improvement (43.2% [95% CI 35.4-51.1] vs. 33.4% [95% CI 22.5-44.2]) and ISGA success (31.7% [95% CI 24.3-39.0] vs. 21.5% [95% CI 12.1-30.9]) at day 29 were higher in the crisaborole vs. vehicle group. A greater reduction in change from baseline in weekly average PP-NRS score at week 4 was observed in the crisaborole vs. vehicle group (LSM: -1.98 [95% CI -2.34 to -1.62] vs. -1.08 [95% CI -1.63 to -0.53]). No new safety signals were observed.

CONCLUSION

Crisaborole was effective and well tolerated in Chinese patients aged ≥ 2 years with mild to moderate AD.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04360187.

Topical Application of a PDE4 Inhibitor Ameliorates Atopic Dermatitis through Inhibition of Basophil IL-4 Production

Phosphodiesterase 4 inhibitors have been approved for the treatment of atopic dermatitis. However, the cellular and molecular mechanisms underlying their therapeutic effect remain to be fully elucidated. In this study, we addressed this unsolved issue by analyzing the action of difamilast, a novel phosphodiesterase 4 inhibitor, on an oxazolone-induced skin allergic inflammation commonly used as a mouse model of atopic dermatitis. Topical application of difamilast ameliorated skin inflammation in association with reduced IL-4 expression even when the treatment commenced 4 days after the initiation of oxazolone challenge, showing its therapeutic effect on atopic dermatitis. IL-4-deficient mice displayed milder skin inflammation than did wild-type mice, and the difamilast treatment had little or no further therapeutic effect. This was also the case in mice depleted of basophils, predominant producers of IL-4 in the skin lesion, suggesting that difamilast may act on basophils. Notably, basophils accumulating in the skin lesion showed highly upregulated expression of Pde4b encoding the B subtype of the phosphodiesterase 4 family. Difamilast suppressed IL-4 production from basophils activated in vitro, at least in part, through inhibition of ERK phosphorylation. Taken together, difamilast appeared to ameliorate atopic dermatitis inflammation through the suppression of basophil IL-4 production in the skin lesion.

Liangxue-Qushi-Zhiyang Decoction Ameliorates DNCB-Induced Atopic Dermatitis in Mice through the MAPK Signaling Pathway Based on Network Pharmacology

The traditional prescription of Liangxue-Qushi-Zhiyang decoction (LQZ) has been demonstrated to be efficacious in treating atopic dermatitis (AD), a chronic inflammatory skin disorder marked by intense itching, redness, rashes, and skin thickening. Nevertheless, there has been an inadequate systematic exploration of the potential targets, biological processes, and pathways for AD treatment through LQZ. The study objective was to evaluate the efficacy and possible mechanism of LQZ in AD mice. In our study, we identified the primary compounds of LQZ, analyzed hub targets, and constructed a network. Subsequently, the predicted mechanisms of LQZ in AD were experimentally studied and validated in vivo, as determined by network pharmacological analysis. A total of 80 serum components of LQZ were identified through ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), among which 49 compounds were absorbed into the bloodstream. Our results indicated that LQZ targets six putative key factors in the MAPK signaling pathway, which play essential roles in AD, namely, EGFR, p-MAPK1/3, p-MAPK14, IL-1β, IL-6, and TNF-α. We observed spleen coefficient, dermatitis scores, and ear thickness were all downregulated in 2,4-dinitrochlorobenzene (DNCB)-induced mice after LQZ treatment. Histological analysis of the dorsal and ear skin further revealed that LQZ significantly decreased skin inflammation, epidermal thickness, and mast cell numbers compared to the DNCB group. Our study demonstrated the effectiveness of LQZ in reducing epidermal and dermal damage in a mouse model of AD. Furthermore, our findings suggest that downregulating the MAPK signaling pathway could be a potential therapeutic strategy for the treatment of AD.

Topical Treatments in Atopic Dermatitis: An Expansive Review

Atopic dermatitis (AD) is a common inflammatory skin condition found worldwide. It impacts patient quality of life (QoL) and is thought to arise as an inflammatory response to epidermal barrier dysfunction and hypersensitivity. AD can lead to large out-of-pocket costs and increased healthcare expenses over a lifetime. An analysis of all randomized control trials conducted since 1990 on topical therapies for AD were reviewed, including 207 trials in the final analysis. It was found that an average of 226 patients were enrolled over 2.43 arms. Common topical treatments included corticosteroids, calcineurin inhibitors, JAK inhibitors, and phosphodiesterase inhibitors. The most utilized tools to identify treatment efficacy were the EASI, IGA, SCORAD, and PGA. There was a paucity of data on trials that evaluated efficacy, QoL, and cost of treatment simultaneously. This review highlights the need for comprehensive trials that evaluate multiple aspects of treatment, including financial cost and QoL impact, to ensure each patient has the best treatment modality for the management of their AD.

Atopic Dermatitis in Children

Atopic dermatitis (AD) is extremely common in the pediatric population, and most children with AD will first present to their primary care provider (PCP). The PCP can recognize AD by its clinical features, including itch, a chronic relapsing course, and the characteristic eruption. The cornerstone of AD therapy is dry skin care, typically a short daily bath/shower followed by an emollient applied to all skin. Most children with AD will also require topical medications, such as topical corticosteroids and/or topical nonsteroidal therapies. For children with more severe disease, systemic agents, including several novel therapies, may be required. In managing AD, the clinician must monitor for side effects of medications as well as complications of the AD itself, the most common of which is secondary infection. An understanding of the pathogenesis, treatments, and complications of AD is essential for the PCP, as untreated (or undertreated) AD has a significant impact on the quality of life of affected children and their caregivers. [Pediatr Ann. 2024;53(4):e121-e128.].

Updates in atopic dermatitis for the primary care physician: A review of advances in the understanding and treatment of atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory skin condition occurring in both pediatric and adult patients. Pruritus is a clinical hallmark of the disease, and patients with AD often experience disruptions to their quality of life. The pathogenesis of AD is a complex and multifactorial interplay between genetic factors, epidermal barrier disruption, and immune dysregulation. Clinically, AD is characterized by pruritus, eczematous skin changes, and age-specific lesion distribution patterns. Infants and young children tend to have AD lesions on their face and extensor surfaces of their extremities while older children and adults tend to have AD lesions on flexural surfaces of their extremities. Many patients also experience a chronic and relapsing disease course. Due to the chronicity and severe pruritus, lesions often undergo secondary changes like lichenification. Patients with AD can experience a number of comorbidities including other atopic disease (i.e. allergic rhinitis, asthma), skin infections, cardiovascular, and neuropsychiatric illnesses. Management of AD depends on the severity of the disease as well as the distribution of the disease. Traditionally, treatment of AD included the use of moisturizers / emollients, topical corticosteroids or topical calcineurin inhibitors, or systemic therapy with non-selective immunosuppressants such as corticosteroids, cyclosporine, azathioprine, or similar. However, in the past decade, new biologic and small molecule drugs, both topical and systemic, have become important therapeutic options for AD patients, especially for those with moderate-to-severe disease. The development of these medications, following decades of research to better understand AD, are designed to specifically target various components of immune dysregulation and inflammation implicated in the pathogenesis of AD. Their successful development and deployment now allow for an exciting new era of treatment for individuals suffering from atopic dermatitis.

Maintenance of Investigator's Static Global Assessment Response with Once-Daily Crisaborole in Participants with Mild to Moderate Atopic Dermatitis

INTRODUCTION

Treatments for atopic dermatitis (AD) often fail to achieve lasting disease control. In the CrisADe CONTROL phase III study (ClinicalTrials.gov: NCT04040192), participants aged ≥ 3 months with mild to moderate AD treated with once-daily (QD) crisaborole, following initial treatment success with crisaborole twice daily (BID), had longer periods of flare-free maintenance, a higher number of flare-free days, and a lower number of flares compared with those who received vehicle. The study was an exploratory analysis of data on the maintenance of response per Investigator's Static Global Assessment (ISGA; ISGA score of 0 [clear] or 1 [almost clear]) during the CrisADe CONTROL study through week 52.

METHODS

Exploratory endpoints were the time to ISGA response during the open-label run-in period, and the maintenance of ISGA response and the severity and duration of flares during the double-blind maintenance period. Outcomes were stratified by age (participants aged 3 months to < 12 years and ≥ 12 years) and duration of crisaborole BID treatment (< 4 weeks or ≥ 4 weeks) during the open-label run-in period.

RESULTS

During the open-label run-in period, the median time to ISGA response was 41.5 days. From week 4 to week 52 of the double-blind maintenance period, the proportion of participants who maintained ISGA response was greater with crisaborole versus vehicle, and this difference was statistically significant up to week 36 (P < 0.05). Duration of flare periods during the maintenance period were 54.1 and 54.0 days for the vehicle and crisaborole-treated groups, respectively. Numerically fewer crisaborole-treated participants experienced a flare with an ISGA score of ≥ 2 compared with vehicle-treated participants (64.8% vs. 74.4%, respectively). Findings were comparable across most subgroups.

CONCLUSIONS

Adult and pediatric participants with mild to moderate AD at baseline who had achieved responder criteria (treatment success) with crisaborole BID during the run-in period maintained response per ISGA with crisaborole QD during the double-blind maintenance period through week 52.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04040192.

Advancing Treatment in Atopic Dermatitis: A Comprehensive Review of Clinical Efficacy, Safety, and Comparative Insights Into Corticosteroids, Calcineurin Inhibitors, and Phosphodiesterase-4 Inhibitors as Topical Therapies

Atopic dermatitis (AD) is a pervasive and multifaceted dermatological disorder causing daily distress to afflicted individuals worldwide. This comprehensive review synthesizes the historical and contemporary advancements in therapeutic strategies, offering a critical analysis of their efficacy, safety profiles, and adaptability. The enduring role of topical corticosteroids in managing AD is examined, acknowledging their potent anti-inflammatory properties alongside their potential adverse side effects, particularly in extended usage. The article explores the utilization of topical calcineurin inhibitors like tacrolimus and pimecrolimus, highlighting their novel anti-inflammatory pathways while also scrutinizing concerns over potential malignancies that relegate them to second-line therapy. The present investigation features the emergence of crisaborole, a phosphodiesterase four inhibitor. Its innovative mode of action, benign safety profile, and applicability to mild and moderate AD are thoroughly evaluated. The review also includes challenges, particularly cost considerations, which constrain accessibility and necessitate nuanced implementation in therapeutic regimens. This study underscores the need for persistent investigation, teamwork, and innovations in managing AD. In this regard, AD requires a united approach between clinicians, researchers, affected individuals, and policymakers to refine patient-focused treatment and develop precise, economical strategies to address this chronic and frequently life-altering health condition.

Comparative efficacy of systemic treatments for atopic dermatitis in adults

INTRODUCTION

Atopic dermatitis is a prevalent skin condition causing dry, pruritic, inflammatory skin lesions that can result in patient distress. Various emerging classes of therapy, including biologics and Janus kinase inhibitors, have been developed in recent years.

AREAS COVERED

A literature search of PubMed was conducted to explore existing literature and clinical trials. Treatment options and adverse effects were summarized by class and severity. JAK inhibitors and biologics are efficacious options for adults with severe atopic dermatitis. Using the Eczema Area and Severity Index (EASI) from 11 randomized control trials, the highest efficacy was seen with upadacitinib 30 mg with 70% of patients achieving EASI-75. Older, immune-inhibiting treatment options are still appropriate options to improve patient conditions. A meta-analysis of 39 randomized control trials concluded high dose cyclosporine is more effective at improving quality of life and itch when compared to azathioprine and methotrexate. Newly developed topical and systemic medications improve disease and itch severity and can be considered in patients without adequate control with their initial treatment regimen. Adverse effects must be considered when using the newer options, although major adverse events were not seen.

EXPERT OPINION

Current management options are efficacious, but adherence is required for any effect.

Satisfaction with Control of Mild to Moderate Atopic Dermatitis with Ruxolitinib Cream: US Physician and Patient Perspectives

INTRODUCTION

The 2021 US approval of ruxolitinib cream for treatment of atopic dermatitis (AD) in patients aged ≥ 12 years was based on the results of two pivotal phase 3 studies. Currently, real-world data to describe effectiveness of ruxolitinib cream and physician satisfaction with treatment remain limited. Our objective is to describe disease control among adults with mild to moderate AD prescribed ruxolitinib cream and physician satisfaction with treatment.

METHODS

Data were from the Adelphi AD Disease Specific Programme™, a US real-world, cross-sectional survey of physician-reported data, undertaken between August 2022 and March 2023. For patients aged ≥ 18 years, physicians reported patient demographics, clinical characteristics, treatment patterns, and physician satisfaction with disease control. Descriptive analysis of data for patients with mild to moderate AD prior to the initiation of ruxolitinib cream and treated with ruxolitinib cream for ≥ 1 month was undertaken.

RESULTS

Among physician-reported data from 1360 patients with AD, 149 patients had received ruxolitinib cream (in combination or as monotherapy) for ≥ 1 month, including 59 patients receiving monotherapy. Prior to treatment with ruxolitinib cream, 84.6% of patients had moderate AD (Investigator's Global Assessment, IGA of 3), whereas after treatment (median duration, 26 weeks), only 21.5% had an IGA of 3, with 48.3% of patients having clear or almost clear skin (IGA of 0/1). For these patients, 81.2% were not currently experiencing a flare, and physicians were satisfied with disease control for 87.3%. Results were similar in patients receiving monotherapy. The most frequent physician-reported reasons for prescribing ruxolitinib cream included relieving itch, improving lesion redness/thickness, achieving disease control, and reducing/controlling flares.

CONCLUSIONS

These real-world findings demonstrate effective disease control and physician satisfaction with ruxolitinib cream for the treatment of AD in adults in a clinical practice setting. Outcomes were similar whether ruxolitinib cream was prescribed as monotherapy or in combination regimens, suggesting a role for ruxolitinib cream across the spectrum of disease.

Preclinical pharmacokinetic investigation of the bioavailability and skin distribution of HY-072808 ointment, a novel drug candidate for the treatment of atopic dermatitis, in minipigs by a newly LC-MS/MS method

HY-072808 is a novel phosphodiesterase 4 inhibitor clinically used for topical atopic dermatitis treatment. Cytochrome P450 enzymes are involved in transforming it into major metabolite ZZ-24. An efficient UPLC-MS/MS method was established to detect HY-072808 and ZZ-24 in plasma and skin tissues of minipigs.One-step protein precipitation was performed with acetonitrile. Subsequently, elution was served with a methanol and water gradient containing 0.1% formic acid for 3.5 min. The plasma and skin tissue concentrations of HY-072808 and ZZ-24 showed good linearity from 0.200 to 200 ng/mL.The experimental minipigs exhibited low systemic exposure and bioavailability of 3.1-7.6% after transdermal application of 1-4% HY-072808 ointment. Multiple topical administrations over seven consecutive days showed a minor accumulation in systemic exposure, with accumulation factors of 2.3 and 4.0 for HY-072808 and ZZ-24, respectively.The distribution of HY-072808 ointment among different cortical layers in minipigs was studied for the first time. Following transdermal application of 2% HY-072808 ointment, the concentration in plasma and skin tissues in the order of epidermis > dermis > subcutaneous tissue ≈ subcutaneous muscle ≈ plasma; at 48 h after the administration, the epidermis and dermis still had a high concentration of the drug.

Circulating Monocytes Are Predictive and Responsive in Moderate-to-Severe Plaque Psoriasis Subjects Treated with Apremilast

Monocytes play a critical role in the inflammation associated with psoriasis, and their abnormalities have been reported as biomarkers of cardiovascular event risk, a psoriasis comorbidity. Monocytic cells in chronic inflammatory disorders express elevated levels of cAMP phosphodiesterase. Restoring cAMP levels using the oral cAMP phosphodiesterase-4 inhibitor, apremilast, improves clinical outcomes for a subset of patients with psoriasis. We asked whether aberrant monocyte subsets or transcriptomic pathways can function as biomarkers of psoriasis endotypes that can predict enhanced clinical responses to cAMP phosphodiesterase inhibition. A 16-week open-label study of 22 patients with monocyte flow cytometric and transcriptomic analysis was performed. Subjects with elevated hyperadhesive monocyte doublets at baseline were more likely to be responders to apremilast (P < .0001); 82% of subjects with elevated hyperadhesive monocyte doublets achieved 50% reduction in PASI compared with 46% in those without elevated doublets. We observed a significant reduction in hyperadhesive monocyte-containing doublets and monocyte-platelet aggregates, suggesting an effect of apremilast on the adhesiveness of blood monocytes during chronic inflammation. Monocyte differentially expressed gene transcripts predictive of clinical response uncovered pharmacoendotypes with distinct patterns of nucleotide metabolism, energetics, and differentiation. Further study to understand the basis of drug responsiveness and to develop an apremilast psoriasis treatment algorithm using monocyte-refined gene expression is required to validate and become practical in clinical use, offering patients a test that personalizes their likelihood of clinical response.

Efficacy and Safety of PF-07038124 in Patients With Atopic Dermatitis and Plaque Psoriasis: A Randomized Clinical Trial

Importance

Atopic dermatitis (AD) and plaque psoriasis are inflammatory skin diseases with unmet need for effective topical treatments with few application site reactions.

Objective

To assess the efficacy and safety of the topical phosphodiesterase 4 inhibitor PF-07038124 in patients with AD and plaque psoriasis.

Design, Setting, and Participants

This phase 2a, randomized, double-blind clinical trial was conducted from December 21, 2020, to August 18, 2021, at 34 sites across 4 countries. Eligible patients (aged 18-70 years) had mild to moderate AD (covering 5%-20% body surface area) or plaque psoriasis (covering 5%-15% body surface area). Data were analyzed until December 15, 2021.

Interventions

Patients were randomized (1:1) to PF-07038124, 0.01%, topical ointment or vehicle once daily for 6 weeks.

Main Outcomes and Measures

The primary end point was the percent change from baseline (CFB) in the Eczema Area and Severity Index (EASI) total score among patients with AD and in the Psoriasis Area and Severity Index (PASI) score among patients with plaque psoriasis at week 6. Safety measures included treatment-emergent adverse events, including application site reactions.

Results

Overall, 104 patients were randomized (mean [SD] age, 43.0 [15.4] years; 55 [52.9%] women; 4 [3.8%] Asian, 13 [12.5%] Black, and 87 [83.7%] White), including 70 with AD (41 women [58.6%]; mean [SD] ages, 41.4 [16.6] years in the PF-07038124 group and 36.1 [13.9] years in the vehicle group) and 34 with plaque psoriasis (20 men [58.8%]; mean [SD] ages, 51.8 [12.3] years in the PF-07038124 group and 51.2 [10.8] years in the vehicle group). Baseline characteristics were generally balanced. At week 6, the PF-07038124 groups showed significantly greater improvements compared with vehicle groups in EASI (least-squares mean CFB, -74.9% vs -35.5%; difference, -39.4% [90% CI, -58.8% to -20.1%]; P < .001) and PASI scores (CFB, -4.8 vs 0.1; difference, -4.9 [90% CI, -7.0 to -2.8]; P < .001). The number of patients with treatment-emergent adverse events was comparable between treatment groups in patients with AD (PF-07038124, 9 [25.0%]; vehicle, 9 [26.5%]) and plaque psoriasis (PF-07038124, 3 [17.6%]; vehicle, 6 [35.3%]). There were no application site reactions with PF-07038124 treatment.

Conclusions and Relevance

Topical PF-07038124 was well tolerated and demonstrated superior efficacy compared with vehicle in patients with mild to moderate AD and plaque psoriasis.

Trial Registration

ClinicalTrials.gov Identifier: NCT04664153.

Topical Prescription Management

With recent advances in topical therapies for atopic dermatitis (AD), steroid-sparing options like calcineurin inhibitors, Janus kinase (JAK) inhibitors, and phosphodiesterase-4 (PDE-4) inhibitors are becoming mainstays in therapy, underscoring the importance of careful selection and usage of topical corticosteroids (TCSs) to minimize side effects. Alongside the necessity of emollient use, these steroid-sparing alternatives offer rapid itch relief and efficacy in improving disease severity. While TCSs still hold a prominent role in AD management, promising novel topical treatments like tapinarof and live biotherapeutics to modulate the skin microbiome are also discussed. Overall, the recent addition of novel topical therapies offers diverse options for AD management and underscores the importance of topical treatments in the management of AD.

Impact of Crisaborole in Treatment-Experienced Patients With Mild-to-Moderate Atopic Dermatitis

Background: Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor for the treatment of patients with mild-to-moderate atopic dermatitis (AD). Objective: To assess the efficacy and safety of crisaborole in patients with AD who had received prior treatment with (a) corticosteroids (systemic or topical) or topical calcineurin inhibitors (TCIs) or (b) topical corticosteroids (TCSs) or TCIs or (c) who were treatment-naive (TN). Methods: This post hoc analysis comprised patients aged ≥2 years with mild-to-moderate AD. Patients were assigned (2:1) to receive crisaborole or vehicle twice daily for 28 days. Patient response was assessed with the Investigator's Static Global Assessment (ISGA), Dermatology Life Quality Index (DLQI), Children's Dermatology Life Quality Index (CDLQI), and Dermatitis Family Impact (DFI) tools. Safety was also assessed. Results: A significantly higher percentage of patients treated with crisaborole versus vehicle achieved ISGA success regardless of treatment history. Patients treated with crisaborole had significant reductions in DLQI, CDLQI, and DFI scores versus those who received vehicle regardless of treatment history, with the exception of DLQI and DFI scores in the TN group. Crisaborole was well tolerated in all subgroups. Conclusion: Crisaborole demonstrated a favorable efficacy and safety profile in both treatment-experienced and TN patients. ClinicalTrials.gov, NCT02118766 and NCT02118792.

Topical treatments for atopic dermatitis (eczema): Systematic review and network meta-analysis of randomized trials

BACKGROUND

Atopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects.

OBJECTIVE

We sought to systematically synthesize the benefits and harms of AD prescription topical treatments.

METHODS

For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT databases to September 5, 2022, for randomized trials addressing AD topical treatments. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. We classified topical corticosteroids (TCS) using 7 groups-group 1 being most potent. This review is registered in the Open Science Framework (https://osf.io/q5m6s).

RESULTS

The 219 included trials (43,123 patients) evaluated 68 interventions. With high-certainty evidence, pimecrolimus improved 6 of 7 outcomes-among the best for 2; high-dose tacrolimus (0.1%) improved 5-among the best for 2; low-dose tacrolimus (0.03%) improved 5-among the best for 1. With moderate- to high-certainty evidence, group 5 TCS improved 6-among the best for 3; group 4 TCS and delgocitinib improved 4-among the best for 2; ruxolitinib improved 4-among the best for 1; group 1 TCS improved 3-among the best for 2. These interventions did not increase harm. Crisaborole and difamilast were intermediately effective, but with uncertain harm. Topical antibiotics alone or in combination may be among the least effective. To maintain AD control, group 5 TCS were among the most effective, followed by tacrolimus and pimecrolimus.

CONCLUSIONS

For individuals with AD, pimecrolimus, tacrolimus, and moderate-potency TCS are among the most effective in improving and maintaining multiple AD outcomes. Topical antibiotics may be among the least effective.

Elemental exchange: Bioisosteric replacement of phosphorus by boron in drug design

Continuous efforts are being directed toward the employment of boron in drug design due to its advantages and unique characteristics including a plethora of target engagement modes, lower metabolism, and synthetic accessibility, among others. Phosphates are components of multiple drug molecules as well as clinical candidates, since they play a vital role in various biochemical functions, being components of nucleotides, energy currency- ATP as well as several enzyme cofactors. This review discusses the unique chemistry of boron functionalities as phosphate bioisosteres - "the boron-phosphorus elemental exchange strategy" as well as the superiority of boron groups over other commonly employed phosphate bioisosteres. Boron phosphate-mimetics have been utilized for the development of enzyme inhibitors as well as novel borononucleotides. Both the boron functionalities described in this review-boronic acids and benzoxaboroles-contain a boron connected to two oxygens and one carbon atom. The boron atom of these functional groups coordinates with a water molecule in the enzyme site forming a tetrahedral molecule which mimics the phosphate structure. Although boron phosphate-mimetic molecules - FDA-approved Crisaborole and phase II/III clinical candidate Acoziborole are products of the boron-phosphorus bioisosteric elemental exchange strategy, this technique is still in its infancy. The review aims to promote the use of this strategy in future medicinal chemistry projects.

A single-centre prospective study comparing efficacy and safety of apremilast with cyclosporine in moderate to severe atopic dermatitis

BACKGROUND

Apremilast regulates several pro-inflammatory signals involved in atopic dermatitis (AD).

METHODS

A randomized, open-labelled study was conducted at a tertiary care centre in India. Fifty patients with AD of >1 year duration were randomly assigned in a 1:1 ratio to receive either apremilast (30 mg twice daily after initial titration) or cyclosporine (5 mg/kg/day) for 24 weeks, followed by a 12-week follow-up period. Primary outcome was mean percentage change in Eczema Area and Severity Index (EASI) from baseline to week 24. Secondary outcome measures were proportion of patients achieving EASI 75, EASI 90, ≥2-point improvement in Investigator's Global Assessment (IGA), SCORing Atopic Dermatitis (SCORAD) 75 at week 24 and percentage of patients experiencing ≥1 adverse effect (AEs).

RESULTS

Mean percentage change in EASI (standard deviation) was -67.79% [22.44] in the apremilast treatment group and -83.06% [21.20] in the cyclosporine treatment group (p < 0.05). At week 24, 52.38% of patients in the apremilast group and 78.26% in the cyclosporine group achieved EASI 75 (p < 0.05); 14.29% in the apremilast group and 52.17% in the cyclosporine group achieved EASI 90 (p < 0.05) and 80.95% in the apremilast group and 82.60% patients achieved ≥2 point reduction in IGA (p > 0.05). 57.14% of patients achieved SCORAD 75 in the apremilast group and 69.56% in the cyclosporine group (p > 0.05). Mean time taken to achieve EASI 75 in the apremilast group was 4.50 ± 4.62 weeks, while it was 3.96 ± 3.43 weeks in the cyclosporine group (p > 0.05). Incidence of AEs was 28.57% in the apremilast group and 21.74%) in the cyclosporine group.

CONCLUSIONS

Apremilast demonstrated lesser efficacy in comparison to cyclosporine; it has the advantage of a favourable safety profile and requires no laboratory monitoring.

Current and Emerging Therapies for Atopic Dermatitis in the Elderly

Atopic dermatitis (AD) in the elderly has recently emerged as a distinct subgroup of AD, garnering widespread concern due to its increasing global incidence rate. Epidermal barrier dysfunction, inflammatory response, and chronic pruritus interact with each other, contributing to the pathogenesis and pathophysiology of AD in the elderly. Although fundamental medications are essential for managing AD in the elderly, older adults often struggle with regular usage of moisturizing emollients, topical medications, and avoidance of environmental triggers, leading to recurrent or even exacerbated disease progression. Therefore, a systematic medication approach is necessary to control pruritus and skin lesions. Traditional systemic treatments may not adequately meet the treatment needs of moderate and severe AD in the elderly and may even pose certain safety risks. Biologics and Janus kinase (JAK) inhibitors, exhibiting excellent clinical efficacy, have made significant breakthroughs in AD treatment. Existing evidence suggests that dupilumab, a human monoclonal IgG4 antibody, has been confirmed as an effective and safe first-line systematic treatment for moderate to severe AD in the elderly, with no notable differences between adults and the elderly. However, the limited inclusion of elderly patients in related clinical studies hinders the generalizability of these findings. As older patients face a higher risk of adverse events with JAK inhibitors, JAK inhibitors are recommended when no other suitable treatment options are available. Obtaining population-specific data is crucial for making evidence-based treatment choices when managing AD in older adults with JAK inhibitors.

Novel Vehicles For Drug Delivery in Atopic Dermatitis: A Narrative Review

INTRODUCTION

Atopic dermatitis (AD) causes dry and itchy skin and inflammation that severely impairs the quality of life of affected children and adults. While topical glucocorticosteroid application is typically the first-line treatment of choice, steroid treatment is associated with side effects and, increasingly, patient concerns about prolonged use. Novel drugs and drug delivery vehicles are required for patients with AD.

OBJECTIVES

To summarize the current literature on novel topical agents for atopic dermatitis and novel delivery vehicles.

METHODS

A literature search was conducted, and a narrative review was compiled to summarize recent evidence.

RESULTS

Novel topical drugs approved or in late-phase clinical trials for the treatment of AD include the Janus kinase inhibitor ruxolitinib, the phosphodiesterase-4 inhibitors crisaborole, and roflumilast, and the aryl hydrocarbon receptor activator tapinarof. While current topical drugs for AD are delivered via creams, ointments, gels, and related vehicles, novel delivery approaches such as electrospun patches, sprays, liposomes, nanoparticles, and lasers are being developed to enhance transdermal delivery, reduce side effects, and increase treatment adherence.

CONCLUSIONS

Topical application of creams or ointments is currently the predominant vehicle for the delivery of atopic dermatitis drugs. In vitro studies on novel vehicles show promising results to overcome the issues associated with topical delivery. Still, these findings have to be corroborated by controlled studies with human patients in the future.

Atopic dermatitis: a brief review of recent advances in its management

Atopic dermatitis (AD) is a common inflammatory skin disorder characterized by recurrent eczematous lesions and intense itching. The disorder affects people of all ages and ethnicities, has a substantial psychosocial impact on patients and relatives, and is the leading cause of the global burden of skin diseases. Atopic dermatitis is associated with an increased risk of multiple comorbidities, including food allergies, asthma, allergic rhinitis, and mental health disorders. The pathophysiology is complex and involves a strong genetic predisposition, epidermal dysfunction, and T-cell-driven inflammation. Although type-2 mechanisms are dominant, there is increasing evidence that the disorder involves multiple immune pathways. Until recently, the management of AD rested mainly on the judicious use of emollients, topical steroids, and topical calcineurin inhibitors in the majority of patients, and systemic immunosuppressants were advocated in severely diseased patients. However, in the last few years, new therapeutic strategies have been designed and developed to target the various steps in the chain of molecular events that lead to the AD phenotype. This review highlights the recent advancements in the management of AD.

Atopic Dermatitis Across Shades of Skin

Atopic dermatitis (AD) is a chronic, heterogeneous inflammatory skin disease that is associated with immense patient burden globally. There is increasing appreciation of disparities among patients identified as having skin of color (SOC), which often refers to patients of non-White race or non-European ancestry, but can broadly include individuals from a number of different racial, ethnic, ancestral, and skin pigmentation groups based on definition. In this narrative review, we discuss key terminology as it relates to AD across shades of skin, including modern definitions of 'race', 'ethnicity', and 'SOC'. We then synthesize the current literature describing disparities in AD prevalence, disease recognition, and burden alongside current data regarding genetic and immunologic findings across SOC populations. In the context of these findings, we highlight key concomitant social determinants of health, including environmental factors, socioeconomic status, and access to care, for which race often serves as a proxy for true biological and genetic differences. Finally, we discuss future efforts to shift to a more inclusive understanding of AD to encompass all shades of skin, to ensure equitable representation of diverse populations in high impact research, and intensify efforts to address the critical upstream factors driving observed disparities.

A Review of Existing and New Treatments for the Management of Hand Eczema

Hand eczema is a chronic condition that affects an estimated 14.5% of the general population. It has severe quality of life ramifications in those that struggle with it, including days missed from work or school, productivity loss and impaired work functioning. For years, the standard of care included topical moisturizing creams, topical steroids and more recently systemic agents. As new therapeutic targets emerge and recent advances are being developed, it is now more possible than ever that hand eczema can be managed via the underlying mechanisms. A review of the literature was conducted to identify current treatment options for hand eczema and chronic hand eczema. The terms 'hand eczema', 'hand dermatitis' were used to search PubMed, CENTRAL and Embase. To identify new therapies still undergoing investigation, we used the terms 'hand eczema', 'hand dermatitis', 'atopic dermatitis', and 'vesicular eczema of hands and/or feet' to search Clinicaltrials.gov for all studies until December 2022. There were 56 ongoing clinical trials identified for pharmacological treatments for hand eczema on Clinicaltrials.gov from 2000 - 2022, with 16 that are new or ongoing. These included studies for dupilumab, ruxolitinib, delgocitinib (LEO124249), gusacitinib (ASN002), AFX 5931, and roflumilast (ARQ-252). Two major classes of drugs emerging for the treatment of hand eczema include IL-4/IL-13 inhibitors and JAK inhibitors. With the increase in efficacy seen with these new drugs, we are also noting improved adverse effect profiles, making them attractive options to add to a clinician's management toolbox for patients with hand eczema.

Crisaborole Inhibits Itch and Pain by Preventing Neutrophil Infiltration in a Mouse Model of Atopic Dermatitis

Crisaborole, a phosphodiesterase 4 (PDE4) inhibitor, has been approved for the treatment of mild to moderate atopic dermatitis. Atopic dermatitis is often associated with increased pain. Using a mouse model, this study investigated whether crisaborole suppresses pain associated with atopic dermatitis and the potential mechanisms underlying it. The mouse model for atopic dermatitis was developed by repeatedly applying MC903. MC903-treated mice had increased spontaneous scratching (itch-related behaviour) and wiping behaviour (pain-related behaviour). Crisaborole was topically applied to the cheek skin of MC903-treated mice, and it reduced both itch- and pain-related behaviours in these mice. Immunofluorescence staining revealed that crisaborole reduced neutrophil infiltration and interaction of neutrophils with sensory neurones. Intradermal injection of S100A8/A9, proinflammatory neutrophil mediator, enhanced not only itch-related behaviours evoked by histamine or chloroquine, but also pain-related behaviours evoked by capsaicin. Calcium imaging of mouse dorsal root ganglion neurones revealed that pretreatment with S100A8/A9 significantly increased calcium responses to histamine and capsaicin, and the proportion of chloroquine-sensitive neurones. These findings suggest that the PDE4 inhibitor reduces itch and pain, in part by inhibiting infiltration of S100A8/A9-containing neutrophils in a mouse model of MC903-induced atopic dermatitis.

Anti-inflammatory and biologic drugs for atopic dermatitis: a therapeutic approach in children and adolescents

Atopic dermatitis (AD) is a chronic inflammatory disease with a heterogeneous pathogenesis correlated with dysregulation of the immune system and a prevalence of the T2-mediated immune pathway. Recent understanding of the pathogenesis of AD has allowed the development of new drugs targeting different mechanisms and cytokines that have changed the treatment approach. The aim of this review is to update knowledge on the standard of care and recent advancements in the control of skin inflammation. In light of recent guidelines, we report on the clinical efficacy of novel treatments, with special attention to situations where biologics and small molecules are involved.

The evolving landscape of immunotherapy for the treatment of allergic conditions

Allergic conditions, such as asthma, chronic urticaria, atopic dermatitis (AD), and eosinophilic esophagitis, have long been treated with oral and topical steroids which resulted in negative off-target effects. However, newer biologic medications are increasingly being developed and approved for treatment of these conditions. These medications have a variety of mechanisms of action to target pathophysiology specific to these diseases. As biologics become more targeted, fewer off-target effects are seen improving tolerability for patients as well as expanded options for treatment of these conditions. This review discusses monoclonal antibody therapies (omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, tezepelumab, and tralokinumab) including their safety and use in asthma, chronic urticaria, AD, and eosinophilic esophagitis.

Update on Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disorder with a lifetime prevalence of up to 20% which can occur at any age but is most common among children. There is a significant burden of pediatric AD in the primary care setting; thus, the ability to recognize and manage AD is of utmost importance to pediatricians. Treatment of AD requires a multifaceted approach based on a patient's severity including behavioral modifications, topical and systemic pharmacologic therapies, and phototherapy.

Knuckle Pads Successfully Treated with 2% Crisaborole Ointment Combined with Triamcinolone Acetonide and Neomycin Plaster: A Case Report

Knuckle pads (KPs) are benign hyperkeratotic fibrous thickening skin disorder characterized by nodules or plaques located on the extensor surface of the joints. However, there are no specific treatments for KPs so far. Here, we reported a case of KPs successfully treated with 2% crisaborole ointment combined with triamcinolone acetonide and neomycin plaster. This combined therapy might be a new therapeutic option for KPs.

JAK1 inhibitors for the treatment of atopic dermatitis: a focus on pharmacokinetic considerations

INTRODUCTION

Atopic dermatitis (AD) is associated with reduced quality of life, depression, and anxiety, making efficacious and safe treatments a priority. We will focus on the safety, efficacy, and pharmacokinetics of JAK1 inhibitors used in the treatment of AD.

AREAS COVERED

In this review, the pharmacodynamics, pharmacokinetics, safety, and efficacy of JAK1 inhibitors for the treatment of atopic dermatitis are discussed. The data was obtained by searching ClinicalTrials.gov, PubMed, and Google Scholar. Articles between January 2012 and March 2023 were considered for inclusion.

EXPERT OPINION

Given the rare, but serious black box warnings with JAK inhibitors, patients and providers may be weary of initiating treatment. In these instances, clinicians may weigh the risks and benefits of treatment with this class. Risk is relative, and while there are risks to treating AD with JAK inhibitors, there are also risks to untreated or undertreated AD, including infection and impairments in mental, physical, and psychosocial function. While JAK1 inhibitors appear to be safe, they were only recently approved for AD in January 2022, and more long-term safety data is needed. We expect to see additional FDA approval of these drugs, new formulations, and more safety and efficacy data in the future.

Guidelines of care for the management of atopic dermatitis in adults with topical therapies

BACKGROUND

New evidence has emerged since the 2014 guidelines that further informs the management of atopic dermatitis (AD) with topical therapies. These guidelines update the 2014 recommendations for management of AD with topical therapies.

OBJECTIVE

To provide evidence-based recommendations related to management of AD in adults using topical treatments.

METHODS

A multidisciplinary workgroup conducted a systematic review and applied the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) approach for assessing the certainty of evidence and formulating and grading recommendations.

RESULTS

The workgroup developed 12 recommendations on the management of AD in adults with topical therapies, including nonprescription agents and prescription topical corticosteroids (TCS), calcineurin inhibitors (TCIs), Janus kinase (JAK) inhibitors, phosphodiesterase-4 inhibitors (PDE-4), antimicrobials, and antihistamines.

LIMITATIONS

The pragmatic decision to limit the literature review to English-language randomized trials may have excluded data published in other languages and relevant long-term follow-up data.

CONCLUSIONS

Strong recommendations are made for the use of moisturizers, TCIs, TCS, and topical PDE-4 and JAK inhibitors. Conditional recommendations are made for the use of bathing and wet wrap therapy and against the use of topical antimicrobials, antiseptics, and antihistamines.

Phosphodiesterase inhibitors and lung diseases

Phosphodiesterase enzymes (PDE) have long been known as regulators of cAMP and cGMP, second messengers involved in various signaling pathways and expressed in a variety of cell types implicated in respiratory diseases such as airway smooth muscle and inflammatory cells making them a key target for the treatment of lung diseases as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, and pulmonary hypertension (PH). The first reported PDE inhibitor was the xanthine, theophylline, described as a non-specific PDE inhibitor and whilst this drug is effective, it also has a range of unwanted side effects. In an attempt to improve the therapeutic window of xanthines, a number of selective PDE inhibitors have been developed for the treatment of respiratory diseases with only the selective PDE 4 inhibitor, roflumilast, being approved for the treatment of severe COPD. However, roflumilast also has a very narrow therapeutic window due to a number of important doses limiting side effects, particularly in the gastrointestinal tract. However, there continues to be research carried out in this field to identify improved selective PDE inhibitors, both by targeting other PDE subtypes (e.g., PDE 7 found in a number of inflammatory and immune cells) and through development of selective PDE inhibitors for pulmonary administration to reduce systemic exposure and improve the side effect profile. This approach has been exemplified by the development of ensifentrine, a dual PDE 3-PDE 4 inhibitor, an inhaled drug that has recently completed two successful Phase III clinical trials in patients with COPD.

Once-Daily Crisaborole Ointment, 2%, as a Long-Term Maintenance Treatment in Patients Aged ≥ 3 Months with Mild-to-Moderate Atopic Dermatitis: A 52-Week Clinical Study

BACKGROUND

Topical treatments for atopic dermatitis (AD) used reactively often fail to achieve lasting disease control; many of these therapies are associated with safety concerns that limit long-term use. Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor for the treatment of mild-to-moderate AD that has potential as a long-term maintenance therapy.

OBJECTIVE

The aim was to evaluate the long-term efficacy and safety of crisaborole once daily (QD) compared to vehicle QD as a maintenance therapy to reduce the incidence of flares in patients with AD who previously responded to crisaborole twice daily (BID).

METHODS

CrisADe CONTROL was a randomized, double-blind, vehicle-controlled, 52-week, phase III study of patients aged ≥ 3 months with mild-to-moderate AD involving ≥ 5% treatable body surface area. Eligible patients received crisaborole BID during an open-label run-in period of up to 8 weeks. Responders were randomly assigned in the double-blind maintenance period to receive either crisaborole QD or vehicle QD. Responders were defined as patients who achieved Investigator's Static Global Assessment (ISGA) success (ISGA score of 0 [clear] or 1 [almost clear] with a ≥ 2-grade improvement) and ≥ 50% improvement in Eczema Area and Severity Index total score (EASI-50) from baseline. Patients who experienced a flare (ISGA score ≥ 2) during the double-blind maintenance period switched to crisaborole BID for up to 12 weeks. During this period, patients were assessed every 4 weeks; if the flare resolved (ISGA score ≤ 1), patients resumed their assigned treatment. The primary endpoint was flare-free maintenance until onset of the first flare. Key secondary endpoints were number of flare-free days, number of flares, and maintenance of pruritus response until onset of the first flare. The incidence of treatment-emergent adverse events was also analyzed.

RESULTS

Overall, 497 patients entered the open-label run-in period with crisaborole BID, of which 270 patients were randomized into the 52-week double-blind maintenance period of the study. Of the 270 patients, 135 were randomly assigned to the crisaborole QD group and 135 were randomly assigned to the vehicle QD group. Median time of flare-free maintenance was longer for patients who received crisaborole versus vehicle (111 vs 30 days, respectively; p = 0.0034). The mean number of flare-free days was higher for patients who received crisaborole versus vehicle (234.0 vs 199.4 days, respectively; p = 0.0346). The mean number of flares was lower for patients who received crisaborole versus vehicle (0.95 vs 1.36, respectively; p = 0.0042). No clear trend was observed in maintenance of pruritus response between crisaborole- and vehicle-treated patients. Crisaborole was well tolerated, with no new or unexpected safety findings when used as maintenance treatment.

CONCLUSIONS

Crisaborole QD was effective and well tolerated for long-term maintenance treatment and flare reduction in adult and pediatric patients with mild-to-moderate AD.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04040192, 31 July 2019.

Efficacy and safety of crisaborole ointment in Chinese and Japanese patients aged ≥2 years with mild-to-moderate atopic dermatitis

Atopic dermatitis is a chronic inflammatory skin disease with a significant impact on the overall wellbeing of patients and their families. Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor approved for the treatment of mild-to-moderate atopic dermatitis in multiple countries. However, in the key pivotal trials, a low proportion of the overall patient population was Asian, therefore the safety and efficacy of crisaborole in the Asian population with atopic dermatitis remains unclear. CrisADe CLEAR was a multicenter, randomized, double-blind, vehicle-controlled, phase 3 study (NCT04360187) to assess the efficacy and safety of crisaborole ointment in Chinese and Japanese patients aged ≥2 years with mild-to-moderate atopic dermatitis involving ≥5% treatable body surface area. Patients were randomly assigned 2:1 to receive crisaborole or vehicle twice daily for 28 days. The primary endpoint was percentage change from baseline in the Eczema Area and Severity Index total score at day 29. Additional endpoints were improvement and success per Investigator's Static Global Assessment score at day 29 and change from baseline on the Peak Pruritus Numerical Rating Scale at week 4. Safety was assessed using rates of treatment emergent adverse events, serious adverse events, and clinically significant changes in vital signs and clinical laboratory parameters. Crisaborole-treated patients showed a significantly greater reduction versus vehicle in percentage change from baseline in Eczema Area and Severity Index total score at day 29 (P = 0.0002). Response rates for achievement of Investigator's Static Global Assessment improvement and success at day 29 were significantly higher for patients treated with crisaborole versus vehicle (P = 0.0124 and P = 0.0078, respectively). Crisaborole-treated patients showed a significantly greater reduction versus vehicle in change from baseline on the Peak Pruritus Numerical Rating Scale at week 4 (P = 0.0009). No new safety signals were identified. Treatment with crisaborole was effective and well tolerated in Chinese and Japanese patients with mild-to-moderate atopic dermatitis.

PDE4 inhibition by difamilast regulates filaggrin and loricrin expression via keratinocyte proline-rich protein in human keratinocytes

BACKGROUND

Difamilast, a topical phosphodiesterase 4 (PDE4) inhibitor, has been shown to be effective for treating atopic dermatitis (AD), but the molecular mechanism involved is unclear. Since skin barrier dysfunction including reduced expression of filaggrin (FLG) and loricrin (LOR) contributes to AD development, difamilast treatment may be able to improve this dysfunction. PDE4 inhibition increases transcriptional activity of cAMP-responsive element binding protein (CREB). Therefore, we hypothesized that difamilast may affect FLG and LOR expression via CREB in human keratinocytes.

OBJECTIVE

To elucidate the mechanism by which difamilast regulates FLG and LOR expression via CREB in human keratinocytes.

METHODS

We analyzed normal human epidermal keratinocytes (NHEKs) treated with difamilast.

RESULTS

We observed increases of intracellular cAMP levels and CREB phosphorylation in difamilast (5 μM)-treated NHEKs. Next, we found that difamilast treatment increased mRNA and protein levels of FLG and LOR in NHEKs. Since reduced expression of keratinocyte proline-rich protein (KPRP) is reported to be involved in skin barrier dysfunction in AD, we examined KPRP expression in difamilast-treated NHEKs. We found that difamilast treatment increased mRNA and protein levels of KPRP in NHEKs. Furthermore, KPRP knockdown using siRNA transfection abolished the upregulation of FLG and LOR in difamilast-treated NHEKs. Finally, CREB knockdown canceled the upregulation of FLG, LOR, and KPRP in difamilast-treated NHEKs, indicating that PDE4 inhibition by difamilast treatment positively regulates FLG and LOR expression via the CREB-KPRP axis in NHEKs.

CONCLUSION

These findings may provide further guidance for therapeutic strategies in the treatment of AD using difamilast.

Novel Therapeutic Targets for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that significantly impacts quality of life. The pathogenesis of AD is a complex combination of skin barrier dysfunction, type II immune response, and pruritus. Progress in the understanding of the immunological mechanisms of AD has led to the recognition of multiple novel therapeutic targets. For systemic therapy, new biologic agents that target IL-13, IL-22, IL-33, the IL-23/IL-17 axis, and OX40-OX40L are being developed. Binding of type II cytokines to their receptors activates Janus kinase (JAK) and its downstream signal, namely signal transduction and activator of transcription (STAT). JAK inhibitors block the activation of the JAK-STAT pathway, thereby blocking the signaling pathways mediated by type II cytokines. In addition to oral JAK inhibitors, histamine H4 receptor antagonists are under investigation as small-molecule compounds. For topical therapy, JAK inhibitors, aryl hydrocarbon receptor modulators, and phosphodiesterase-4 inhibitors are being approved. Microbiome modulation is also being examined for the treatment of AD. This review outlines current and future directions for novel therapies of AD that are currently being investigated in clinical trials, focusing on their mechanisms of action and efficacy. This supports the accumulation of data on advanced treatments for AD in the new era of precision medicine.