Efficacy and Safety of Crisaborole Ointment, 2%, for the Treatment of Mild-to-Moderate Atopic Dermatitis Across Racial and Ethnic Groups

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 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.

Special Considerations of Atopic Dermatitis in Skin of Color

Atopic dermatitis (AD) is a chronic inflammatory skin condition with heterogeneous presentations and prevalence across different skin tones. In this chapter, AD is explored through the lens of racial and ethnic diversity, emphasizing the special considerations among patients with skin of color (SOC). Specific ethnic groups may exhibit unique AD phenotypes, and these differences pose unique diagnostic and management challenges, especially given the disproportionate impact of AD in African American and Asian populations due to environmental exposures and social factors (i.e., decreased access to healthcare resources). Addressing these social disparities, increasing representation in medical education and the clinical space, as well as ongoing research can help better serve this patient population.

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 in skin of colour. Part 2: considerations in clinical presentation and treatment options

Recent advances in atopic dermatitis (AD) present the condition as a heterogeneous disease of distinct endotypes across ethnic groups. AD in people with skin of colour may appear psoriasiform, lichenoid, scaly or papular, with a violaceous colour and there is a higher prevalence of post-inflammatory dyspigmentation compared with affected individuals of White ethnicity. These differences in clinical presentation may limit the use of AD assessment tools in people with skin of colour, leading to the potential for misdiagnosis and underestimation of severity, particularly in relation to assessment of erythema. Recent targeted therapies for AD have been studied in multiple ethnic groups; however, ethnicity-based subgroup analysis is often not performed. Further research is required to understand whether treatment responses or safety may differ among ethnic groups.

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.

Diagnosing Atopic Dermatitis in Skin of Color

Atopic dermatitis (AD) is a pruritic inflammatory skin disease that disproportionately affects skin of color patients. African American, Asian, and Hispanic patients carry disproportionate disease burdens, with increased prevalence, disease severity, and health care utilization. AD has a unique clinical presentation in skin of color patients, often with greater extensor involvement, dyspigmentation, and papular and lichenified presentations. Erythema is also more difficult to appreciate and can result in an underappreciation of disease severity in skin of color patients. In this review, we highlight the important manifestations of AD across all skin types, including nuances in treatment.

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.

Safety profile and tolerability of topical phosphodiesterase 4 inhibitors for the treatment of atopic dermatitis: A systematic review and meta-analysis

Objective

Methods

Results

Conclusions

Treatment of Experimental Autoimmune Encephalomyelitis with an Inhibitor of Phosphodiesterase-8 (PDE8)

After decades of development, inhibitors targeting cyclic nucleotide phosphodiesterases (PDEs) expressed in leukocytes have entered clinical practice for the treatment of inflammatory disorders, with three PDE4 inhibitors being in clinical use as therapeutics for psoriasis, psoriatic arthritis, chronic obstructive pulmonary disease and atopic dermatitis. In contrast, the PDE8 family that is upregulated in pro-inflammatory T cells is a largely unexplored therapeutic target. We have previously demonstrated a role for the PDE8A-Raf-1 kinase complex in the regulation of myelin oligodendrocyte glycoprotein peptide 35–55 (MOG_35–55) activated CD4⁺ effector T cell adhesion and locomotion by a mechanism that differs from PDE4 activity. In this study, we explored the in vivo treatment of experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS) induced in mice immunized with MOG using the PDE8-selective inhibitor PF-04957325. For treatment in vivo, mice with EAE were either subcutaneously (s.c.) injected three times daily (10 mg/kg/dose), or were implanted subcutaneously with Alzet mini-osmotic pumps to deliver the PDE8 inhibitor (15.5 mg/kg/day). The mice were scored daily for clinical signs of paresis and paralysis which were characteristic of EAE. We observed the suppression of the clinical signs of EAE and a reduction of inflammatory lesion formation in the CNS by histopathological analysis through the determination of the numbers of mononuclear cells isolated from the spinal cord of mice with EAE. The PDE8 inhibitor treatment reduces the accumulation of both encephalitogenic Th1 and Th17 T cells in the CNS. Our study demonstrates the efficacy of targeting PDE8 as a treatment of autoimmune inflammation in vivo by reducing the inflammatory lesion load.

Racial/Ethnic Health Disparities in Dermatology in the United States Part 2: Disease-specific Epidemiology, Characteristics, Management, and Outcomes

Racial and ethnic disparities in dermatology negatively affect outcomes such as mortality and quality of life. Dermatologists and dermatologic surgeons should be familiar with disease-specific inequities that may influence their practice. The second article in this two-part continuing medical education series highlights gaps in frequency, clinical presentation, management, and outcomes by race and ethnicity. We review cutaneous malignancies including basal cell carcinoma, squamous cell carcinoma, melanoma, Merkel cell carcinoma, dermatofibrosarcoma protuberans, and cutaneous T cell lymphoma, and inflammatory disorders including atopic dermatitis, psoriasis, hidradenitis suppurativa, acne vulgaris, and rosacea.

An update to the 2013-2014 American Academy of Dermatology (AAD) guidelines for the pharmacological management of atopic dermatitis

INTRODUCTION

Atopic dermatitis is a common dermatologic condition that affects millions of people worldwide, and a standardized approach to treatment was published by the American Academy of Dermatology (AAD) in 2013-14. Since 2014, new FDA-approved treatment options such as dupilumab and crisaborole have changed the landscape of AD management, and future therapies such as JAK inhibitors and anti-interleukin 13 and 31 antibodies appear effective, emphasizing the need for a comprehensive review to give clinicians an updated toolbox to aid in pharmacologic management.

AREAS COVERED

In this review, the authors explore the updated efficacy and safety data on established therapeutic options for AD including topical corticosteroids, topical calcineurin inhibitors, cyclosporine, azathioprine, methotrexate, and mycophenolate mofetil. In addition, the authors also explore trial data and studies on dupilumab, crisaborole, omalizumab, tofacitinib, ruxolinitib, abrocitinib, baricitinib, upadacitinib, delgocitinib, nemoliuzumab, and tralokinumab.

EXPERT OPINION

The AAD guidelines must be updated in the future to include several new treatment modalities that have revolutionized the pharmacologic management of patients with AD, including dupilumab and crisaborole. The future of AD treatment is also extremely bright, as JAK inhibitors and Il-13/31 antibodies have shown convincing results in the improvement of AD patients' lives in various trials and studies that have been examined in this paper.

Chronic itch: emerging treatments following new research concepts

Until recently, itch pathophysiology was poorly understood and treatments were poorly effective in relieving itch. Current progress in our knowledge of the itch processing, the numerous mediators and receptors involved has led to a large variety of possible therapeutic pathways. Currently, inhibitors of IL-31, IL-4/13, NK₁ receptors, opioids and cannabinoids, JAK, PDE4 or TRP are the main compounds involved in clinical trials. However, many new targets, such as Mas-related GPCRs and unexpected new pathways need to be also explored.

Chronic itch in African Americans: an unmet need

Chronic pruritus carries a significant burden of disease and is associated with a negative impact on quality of life. African Americans are disproportionately burdened by chronic pruritic disorders, including but not limited to atopic dermatitis, prurigo nodularis, inflammatory scalp dermatoses, pathologic scarring, and HIV-related dermatoses. Racial differences in skin structure and function may contribute to the pathogenesis of itch in African Americans. Itch perception and response to treatment in African Americans remain understudied and not well understood. As such, there is a large unmet need with regard to the knowledge and management of pruritus in African Americans. This review highlights notable differences in the epidemiology, pathophysiology, genetic predisposition, clinical presentation, and response to treatment for select pruritic skin conditions. By addressing itch as an unmet need in African Americans, we hope to improve patient outcomes and lessen disparities in dermatologic care.

The Role of PDE8 in T Cell Recruitment and Function in Inflammation

Inhibitors targeting cyclic nucleotide phosphodiesterases (PDEs) expressed in leukocytes have entered clinical practice to treat inflammatory disorders, with three PDE4 inhibitors currently in clinical use as therapeutics for psoriasis, psoriatic arthritis, atopic dermatitis and chronic obstructive pulmonary disease. In contrast, the PDE8 family that is upregulated in pro-inflammatory T cells is a largely unexplored therapeutic target. It was shown that PDE8A plays a major role in controlling T cell and breast cancer cell motility, including adhesion to endothelial cells under physiological shear stress and chemotaxis. This is a unique function of PDE8 not shared by PDE4, another cAMP specific PDE, employed, as noted, as an anti-inflammatory therapeutic. Additionally, a regulatory role was shown for the PDE8A-rapidly accelerated fibrosarcoma (Raf)-1 kinase signaling complex in myelin antigen reactive CD4⁺ effector T cell adhesion and locomotion by a mechanism differing from that of PDE4. The PDE8A-Raf-1 kinase signaling complex affects T cell motility, at least in part, via regulating the LFA-1 integrin mediated adhesion to ICAM-1. The findings that PDE8A and its isoforms are expressed at higher levels in naive and myelin oligodendrocyte glycoprotein (MOG)_35–55 activated effector T (Teff) cells compared to regulatory T (Treg) cells and that PDE8 inhibition specifically affects MOG_35–55 activated Teff cell adhesion, indicates that PDE8A could represent a new beneficial target expressed in pathogenic Teff cells in CNS inflammation. The implications of this work for targeting PDE8 in inflammation will be discussed in this review.

Global differences in atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disorder, with a highly variable prevalence worldwide. Recent evidence, however, has shown an increase in prevalence in the Asia Pacific region. Nevertheless, most of the published literature has focused mainly on Western populations, and only few clinical trials have included subgroups of other ethnic populations. Reasons for the observed ethnic and geographical differences in AD are not well established. This calls into question the need for a better understanding of AD pathogenesis and inter-ethnic differences in clinical and immuno-phenotypes. These differences may reflect inherent variability in disease mechanisms between populations, which in turn may impact upon treatment responses such as biologics that are currently tailored mainly to a specific immuno-phenotype (T-helper type 2 dominant). In this article, we reviewed existing literature on the prevalence of AD globally, highlighting differences, if any, in the clinical and immuno-phenotypes of AD between different ethnicities. We discussed genetic and environmental factors that affect AD in different populations and therapeutic considerations. Our review highlights AD as a disease with ethnic-dependent clinical and immunological heterogeneity and calls for greater inclusion of ethnic diversity in future research in order to develop targeted treatments.

The show must go on: an update on clinical experiences and clinical studies on novel pharmaceutical developments for the treatment of atopic dermatitis

PURPOSE OF REVIEW

This review reports on published clinical studies (full publications) with novel therapeutic agents on the treatment of atopic dermatitis with a focus on the last 2 years.

RECENT FINDINGS

Atopic dermatitis is a T-cell driven complex inflammatory skin disease. The secretion of cytokines involving not only particularly Th2 but also Th17 and Th22 cell subsets provides a broad spectrum of potential therapeutical targets. A couple of studies on atopic dermatitis with new therapeutical antibodies that target not only the Th2 cytokines IL-4, IL-13, IL- 31 but also additional targets, such as TSLP, IL-22 or IL-33, and innovative small molecules binding to the histamine-4 receptor, the phosphodiesterase-4, the aryl hydrocarbon receptor or downstream molecules like Janus kinases have recently been published with promising results on symptoms and signs of atopic dermatitis.

SUMMARY

Applications of newly developed drugs in clinical studies or already in daily practice show a substantial progress in the treatment of moderately to severely affected patients with atopic dermatitis not responsive to standard topical treatments with corticosteroids or topical calcineurin inhibitors alone. Moreover, novel treatment approaches generate new knowledge about (anti)inflammatory effects of immune modulations in atopic dermatitis and the heterogeneity of patient subgroups, which may stimulate further innovations in this field.

An Update on the Latest Developments in Nonsteroidal Topical Therapy for Atopic Dermatitis

The author provides a thorough review of the latest topical treatment approaches for atopic dermatitis. Some agents are currently available in the marketplace, while others are in development. Modes of action, including phosphodiesterase-4 inhibition, aryl hydrocarbon receptor activation, and Janus kinase inhibition are discussed. Emphasis is placed on therapeutic approaches related to modes of action, with clinical data included.

Pharmacological management of atopic dermatitis in the elderly

INTRODUCTION

The prevalence of atopic dermatitis (AD) in geriatric populations of industrialized countries is currently estimated at 3-4% and continues to increase. AD is associated with significant morbidity, increased susceptibility to infection, and symptoms of pruritus and pain. Treatments may negatively affect elderly patients; thus, plans should be optimized for this population.

AREAS COVERED

This review summarizes treatment options for AD in the elderly. A systematic review of the literature was conducted using the key terms atopic dermatitis, elderly, geriatric, systemic therapy, therapy, and topical therapy in PubMed. Searches yielded articles on skincare management and topical and systemic pharmacotherapies.

EXPERT OPINION

Proper use of moisturizer is crucial in all patients with AD. Topical corticosteroids are commonly prescribed; however, they carry an increased risk of adverse events such as skin atrophy. Systemic corticosteroids should be avoided in elderly patients due to questionable efficacy and increased adverse events. Topical calcineurin inhibitors and crisaborole are similarly efficacious with an excellent safety profile. Cyclosporine, azathioprine, methotrexate, and mycophenolate mofetil are systemic agents available for the treatment of refractory AD; however, insufficient data exist to indicate the superiority of any one agent. Dupilumab is a safe and efficacious injectable therapy in elderly patients.