Efficacy and Safety of Nail Psoriasis Targeted Therapies: A Systematic Review

INTRODUCTION

Nail changes are frequent clinical findings in patients with cutaneous psoriasis and psoriatic arthritis, often causing significant impairments in quality of life. Numerous targeted therapies have been previously studied for treatment of nail psoriasis, however, newer agents have not been captured in prior systematic reviews. With over 25 new studies published since 2020, the landscape of nail psoriasis systemic treatments is rapidly evolving, warranting analysis of recently approved therapies.

METHODS

An updated systematic review of all PubMed and OVID database studies assessing efficacy and safety of targeted therapies for nail psoriasis was performed, with the goal of incorporating clinical data of recent trials and newer agents, namely brodalumab, risankizumab, and tildrakizumab. Eligibility criteria included clinical human studies reporting at least one of the nail psoriasis clinical appearance outcomes (Nail Psoriasis Severity Index, modified Nail Psoriasis Severity Index).

RESULTS

A total of 68 studies on 15 nail psoriasis targeted therapeutic agents were included. Biological agents and small molecule inhibitors included TNF-alpha inhibitors (adalimumab, infliximab, etanercept, certolizumab, golimumab), IL-17 inhibitors (ixekizumab, brodalumab, secukinumab), IL-12/23 inhibitors (ustekinumab), IL-23 inhibitors (guselkumab, risankizumab, tildrakizumab), PDE-4 inhibitors (apremilast), and JAK inhibitors (tofacitinib). These agents all demonstrated statistically significant improvements in nail outcome scores, compared with placebo or with baseline values, at weeks 10-16 and weeks 20-26, with some studies assessing efficacy up to week 60. Safety data for these agents were acceptable and consistent with known safety profiles within these timepoints, with nasopharyngitis, upper respiratory tract infections, injection site reactions, headache, and diarrhea being the most reported adverse events. Specifically, the newer agents, brodalumab, risankizumab, and tildrakizumab, showed promising outcomes for treatment of nail psoriasis on the basis of current data.

CONCLUSION

Numerous targeted therapies have shown significant efficacy in improving nail findings in patients with psoriasis and psoriatic arthritis. Data from head-to-head trials have shown greater efficacy of ixekizumab over adalimumab and ustekinumab, as well as brodalumab over ustekinumab, while prior meta-analyses have demonstrated superiority of ixekizumab and tofacitinib to other included agents at various assessed timepoints. Further studies on the long-term efficacy and safety of these agents, as well as randomized controlled trials involving comparison with placebo arms, are needed to fully analyze differences in efficacy of newer agents compared with previously established therapies.

Nail Psoriasis: An Updated Review of Currently Available Systemic Treatments

Background

Nail psoriasis (NP) has a prevalence that ranges from 10 to 82% among patients with psoriasis (PsO) and is one of the most common difficult to treat site of psoriasis. We performed a thorough review of the literature, exploring evidence regarding all available NP systemic treatments, describing also in detail NP dedicated clinical trials.

Methods

A literature search was conducted in PubMed and Embase prior to February 2023 using a combination of the terms "nail" AND "psoriasis" AND "systemic therapy" AND/OR "systemic treatment". A total of 47 original studies and case reports were reviewed in this article.

Results

Systemic therapies should be considered when the disorder involves more than 3 nails, has extensive skin and joint involvement, and has a significant impact on QoL, due to their best long-term efficacy. In detail, conventional and biologic systemic drugs demonstrated efficacy in recent trials, including acitretin, methotrexate, cyclosporine, apremilast, adalimumab, infliximab, etanercept, certolizumab, golimumab, ustekinumab, secukinumab, ixekizumab, brodalumab, bimekizumab, guselkumab, risankizumab and tildrakizumab.

Conclusion

Several therapies have demonstrated efficacy and safety in the treatment of NP; however, the choice of treatment depends not only on the severity of the nail involvement, but also on whether PsA is present, the patient's comorbidities other than PsA, previous treatment history, and the patient's drug preferences.

Challenge of Nail Psoriasis: An Update Review

Nail psoriasis is a refractory disease that affects 50-79% skin psoriasis patients and up to 80% of patients with psoriatic arthritis (PsA). The pathogenesis of nail psoriasis is still not fully illuminated, although some peculiar inflammatory cytokines and chemokines seems to be the same as described in psoriatic skin lesions. Psoriatic nail involving matrix can cause pitting, leukonychia, red spots in lunula, and nail plate crumbling, while nail bed involvement can result in onycholysis, oil-drop discoloration, nail bed hyperkeratosis, and splinter hemorrhages. The common assessment methods of evaluating nail psoriasis includes Nail Psoriasis Severity Index (NAPSI), Nail Assessment in Psoriasis and Psoriatic Arthritis (NAPPA), Nail Psoriasis Quality of life 10 (NPQ10), and so on. Treatment of nail psoriasis should be individualized according to the number of involving nail, the affected site of nail and presence of skin and/or joint involvement. Generally, topical therapies are used for mild nail psoriasis, while biologic agents such as etanercept are considered for severe nail disease and refractory nail psoriasis. Even though the current literature has shown some support for the pathogenesis, clinical presentation, or therapies of nail psoriasis, systemic review of this multifaceted disease is still rare to date. We elaborate recent developments in nail psoriasis epidemiology, pathogenesis, anatomy, clinical manifestation, diagnosis, differential diagnosis, and therapies to raise better awareness of the complexity of nail psoriasis and the need for early diagnosis or intervention.

Comparison of guidelines for the use of Ustekinumab for psoriasis in the United States, Europe, and the United Kingdom: A critical appraisal and comprehensive review

The aim of this review is to compare and contrast evidence-based clinical practice guidelines from global dermatological organizations for the use of ustekinumab in psoriasis. Clinical practice guidelines from the American Academy of Dermatology, National Psoriasis Foundation, British Association of Dermatologists, and European S3 were reviewed and compared. Practice guidelines from the three dermatological organizations are similar with regards to treatment dosage and initiation but differ in their recommendations for baseline screening and interval laboratory monitoring, treatment in patients undergoing surgery or receiving live vaccines, and treatment contraindications. Ustekinumab is an effective and well-tolerated systemic treatment for patients with psoriasis and should be considered in the line of therapy that dermatologists discuss with their patients. Consideration should be given to evidence-based practice guidelines of global dermatology organizations to effectively guide treatment decisions in patients with psoriasis.

Toenail Psoriasis during Ustekinumab Therapy: Results and Limitations

Background

Nail psoriasis is a common clinically significant symptom of psoriasis. However, few studies have focused on the characteristics and course of toenail psoriasis.

Objective

To investigate the treatment response of toenail psoriasis during a 52-week period of ustekinumab use.

Methods

Patients were evaluated using the Nail Psoriasis Severity Index (NAPSI) at every injection visit. NAPSI score changes throughout the treatment were analyzed. The treatment response in each toenail and each NAPSI characteristic was also analyzed.

Results

A total of 22 patients with chronic plaque psoriasis with concomitant toenail psoriasis were examined. Several characteristics such as ridging or onychomycosis that mimic psoriasis or hinder the evaluation were identified. NAPSI significantly improved during the treatment (p<0.05). The big and second toes were significantly improved after 52 weeks of ustekinumab treatment (p<0.05). Pitting and oil-drop discoloration were the only two characteristics that showed significant changes post-treatment (p<0.05).

Conclusion

Ustekinumab proved to be efficacious in treating toenail psoriasis. Because of the factors that hinder the NAPSI scoring, only NAPSI scores of the first and second toes can be used.

Nail Psoriasis: Diagnosis, Assessment, Treatment Options, and Unmet Clinical Needs

OBJECTIVE

An estimated 40-50% of patients with psoriasis (PsO) have psoriatic nail disease, which is associated with and directly contributes to a greater clinical burden and worse quality of life in these patients. In this review, we examine how recent advances in the use of new diagnostic techniques have led to improved understanding of the link between nail and musculoskeletal manifestations of psoriatic disease (PsD; e.g., enthesitis, arthritis) and we review targeted therapies for nail PsO (NP).

METHODS

We performed a literature search to identify which systemic therapies approved for the treatment of PsO and/or psoriatic arthritis (PsA) have been evaluated for the treatment of NP, either as a primary or secondary outcome. A total of 1546 articles were identified on February18, 2019, and evaluated for relevance.

RESULTS

We included findings from 66 articles on systemic therapies for the treatment of NP in PsD. With several scoring systems available for the evaluation of psoriatic nail disease, including varied subtypes and application of the Nail Psoriasis Area Severity Index, there was a high level of methodological heterogeneity across studies.

CONCLUSION

NP is an important predictor of enthesitis, which is associated with the early stages of PsA; therefore, it is important for rheumatologists and dermatologists to accurately diagnose and treat NP to prevent nail damage and potentially delay the onset and progression of joint disease. Further research is needed to address the lack of both standardized NP scoring systems and well-defined treatment guidelines to improve management of PsD.

Management of Nail Psoriasis

Nail psoriasis is a chronic nail disorder that requires personalized treatment. General prophylactic measures are suggested for all patients. Topical treatment is considered when treating a few-nail disease, with involvement of 3 or fewer nails, without joint involvement and without (or with mild) skin psoriasis. The ideal formulation should be ointment, solution, or foam. When moderate to severe skin psoriasis or psoriatic arthritis coexists, systemic treatment is suggested. This also should be considered when more than 3 nails are affected or significant impairment of quality of life is present. Conventional systemic agents, biologics, and small molecules are highly efficacious.

The Impact of Nail Psoriasis and Treatment on Quality of Life: A Systematic Review

At least 80% of patients with psoriasis will have nail involvement during their lifetimes. Understanding quality of life (QoL) impact of this condition and associated treatments is of utmost importance. Study objectives were to review the available literature describing patient-reported QoL outcomes in nail psoriasis and relationship with disease severity and treatment. A literature search was performed for English-language articles published prior to August 1, 2020. Articles were included in the review if primary data and validated patient-reported outcome measures assessing QoL were presented, and nail involvement was specifically examined. Fifteen studies were included in the final analysis. Patients with nail psoriasis had higher Psoriasis Area Severity Index and Dermatology Life Quality Index scores than those with psoriasis without nail involvement. The largest percent improvement in QoL score was associated with adalimumab. Studies investigating topicals, intralesionals, and systemic treatments were excluded since only biologic studies utilized validated patient-reported outcome measures. This review affirms that nail psoriasis is physically and emotionally distressing, warranting prompt treatment. Increased efforts are needed to address the impact of treatment on patient QoL using validated outcome measures that assess cosmetic, physical, and social problems.

Small Molecules and Biologics in the Treatment of Nail Psoriasis

Nail psoriasis (PsO) is a disorder with profound impact on patients' quality of life. Several challenges and unmet needs remain in the treatment of nail PsO. Introduction of biologics and small molecules in the treatment of nail PsO has allowed for rapid control of the disease and high efficacy. The aim of this review was to present the published studies on nail PsO therapy with biologics and small molecules and illuminate the results in the studies where the design and outcome evaluation had nail PsO in the forefront.

Joint AAD-NPF guidelines of care for the management and treatment of psoriasis with biologics

Psoriasis is a chronic, inflammatory multisystem disease that affects up to 3.2% of the US population. This guideline addresses important clinical questions that arise in psoriasis management and care, providing recommendations based on the available evidence. The treatment of psoriasis with biologic agents will be reviewed, emphasizing treatment recommendations and the role of the dermatologist in monitoring and educating patients regarding benefits as well as associated risks.

Recommendations for the definition, evaluation, and treatment of nail psoriasis in adult patients with no or mild skin psoriasis: A dermatologist and nail expert group consensus

Nail involvement in psoriasis is common, and the severity of it does not always parallel the intensity of cutaneous disease. We created a consensus group, of which the aim was to provide practical recommendations for the treatment of nail psoriasis in patients without skin psoriasis or with mild skin lesions with no indication for a systemic treatment. This collaborative process was conducted by an international panel of dermatologists with special expertise in nail disorders, using formal consensus methods. During this process, the panel strived to establish an agreement regarding the definition of nail psoriasis, the severity of nail psoriasis, and treatment response. Treatment recommendations are provided regarding nail psoriasis severity and matrix or bed involvement. Few-nail disease was considered as nail psoriasis affecting ≤3 nails. In the case of matrix involvement only, intralesional steroid injections were considered the treatment of choice. Topical steroids alone or in combination with topical vitamin D analogues were suggested for nail psoriasis limited to the nail bed. For the systemic treatment of nail psoriasis acitretin, methotrexate, cyclosporine, small molecules, and biologics may be employed.

New insight into the pathogenesis of nail psoriasis and overview of treatment strategies

Psoriasis is a chronic inflammatory disease affecting up to 3% of the general population. The prevalence of nail involvement in psoriasis patients varies between 15% and 79%. While the nails represent a small portion of the body surface area, psoriasis in these areas can have a disproportionate influence on a patient’s physical and psychosocial activities. Differential diagnosis between an onychomycosis and a psoriatic nail could be challenging; nevertheless, coexistence of onychomycosis and nail psoriasis also occurs and both are common disorders in the general population. Nail psoriasis can be difficult to treat. Treatment of nail psoriasis should consider the body surface area of skin disease, psoriatic arthritis, severity of nail disease, and the impairment in the quality of life. All patients should be tested for onychomycosis before starting a therapy. This recommendation is underlined by the fact that nail psoriasis is mostly treated by immunosuppressive drugs, like steroids, methotrexate, or biologics, which may aggravate mycotic nail infections. Conventional systemic therapy, such as use of steroids, cyclosporine, methotrexate, and retinoid in the long term, can cause organ toxicities. Currently, use of apremilast and tofacitinib favors an early healing of nail psoriasis because they act directly on the pathogenic targets, distressing the inflammatory signals associated with the initiation and maintenance of the disease activity, and as with several conventional synthetic disease modifying antirheumatic drugs, they are characterized by the convenience of oral administration. The number of treatment options has increased considerably in recent years; however, given the heterogeneity of the disease, the therapy should be personalized to individual cases.

Improvement of health-related quality of life and adherence to treatment with calcipotriol-betamethasone dipropionate gel in patients with psoriasis vulgaris

BACKGROUND

Psoriasis is a common, chronic, recurrent, immune-mediated disorder of the skin and joints. It can have a significant negative impact on the physical, emotional and psychosocial wellbeing of affected patients.

OBJECTIVES

To measure improvement in health-related QoL (HRQoL) in Greek patients with psoriasis vulgaris after a month of treatment with calcipotriol-betamethasone dipropionate gel; and evaluate adherence to treatment parameters.

METHODS

The study included 394 psoriasis vulgaris patients from 16 private dermatological practices in Greece, all treated with calcipotriol-betamethasone dipropionate gel. They were evaluated at the first visit and after 4 weeks. Moreover, they completed the Dermatology Life Quality Index (DLQI), while other data such as disease severity, subjective symptoms and adherence, were collected.

RESULTS

At week 4, the DLQI median was reduced by 3.5 points from the baseline (p<0.001; baseline and week 4 median: 4.5 and 1.0 respectively). Pruritus and sleep disorders also improved (p<0.001). Furthermore, 90.1% of the subjects fully adhered to treatment, with a 97.1% mean level of compliance.

CONCLUSIONS

The convincing clinical results, with a distinct improvement in HRQoL, plus the high level of adherence due to its advantageous physical properties, make the calcipotriol-betamethasone dipropionate gel formulation an important, effective and well-tolerated topical therapy to treat psoriasis.

Evidence and Suggested Therapeutic Approach in Psoriasis of Difficult-to-treat Areas: Palmoplantar Psoriasis, Nail Psoriasis, Scalp Psoriasis, and Intertriginous Psoriasis

Psoriasis is resistant to treatment and it shows frequent relapse; systemic treatment is often associated with toxicities, and long-term safety data are lacking for most of the newer drugs like biologics. Moreover, some body areas such as hands, feet, intertriginous areas, scalp, and nails are even more resistant. Frequently, systemic treatments are necessary considering the higher psychological impact on the patient. There is a lack of agreement on the best therapeutic modalities in the management of psoriasis involving difficult-to-treat locations. At present, there are no Indian guidelines for these conditions. Available literature has been reviewed extensively on the treatment of psoriasis involving difficult-to-treat locations; level of evidence has been evaluated as per the Oxford Centre for Evidence-Based Medicine 2011 guideline, and therapeutic suggestions have been developed. Best care has been employed to consider socioeconomic, cultural, genetic, and ethnic factors to prepare a therapeutic suggestion that is appropriate and logical to be used among Indian population and people of similar ethnic and socioeconomic background.

Nail Psoriasis: A Review of Treatment Options

Nail involvement affects 80-90 % of patients with plaque psoriasis, and is even more prevalent in patients with psoriatic arthritis. This review is the result of a systemic approach to the literature and covers topical, intralesional, conventional systemic, and biologic systemic treatments, as well as non-pharmacological treatment options for nail psoriasis. The available evidence suggests that all anti-tumor necrosis factor-α, anti-interleukin (IL)-17, and anti-IL-12/23 antibodies which are available for plaque psoriasis and psoriatic arthritis are highly effective treatments for nail psoriasis. Conventional systemic treatments, including methotrexate, cyclosporine, acitretin, and apremilast, as well as intralesional corticosteroids, can also be effective treatments for nail psoriasis. Topical treatments, including corticosteroids, calcipotriol, tacrolimus, and tazarotene, have also been shown to have a position in the treatment of nail psoriasis, particularly in mild cases. Finally, non-pharmacological treatment options, including phototherapy, photodynamic therapy, laser therapy, and several radiotherapeutic options, are also reviewed but cannot be advised as first-line treatment options. Another conclusion of this review is that the lack of a reliable core set of outcomes measures for trials in nail psoriasis hinders the interpretation of results, and is urgently needed.

Therapeutic Targeting of IL-17 and IL-23 Cytokines in Immune-Mediated Diseases

The discovery of the biological functions of the interleukin-23/-17 axis led to the identification of IL-23 and IL-17 as important participants in the pathogenesis of several immune-mediated diseases. Therapeutic agents targeting these cytokines and/or their receptors have now been developed as potential treatment strategies for common immune-mediated diseases. Anti-IL-17 and anti-IL-12/-23 regimens appear particularly effective in psoriasis, with promising results in spondyloarthropathies also emerging. Overall, these agents appear well tolerated, with adverse-event rates that are commensurate with those in other biologic treatment programs. The strategic utility of these new agents, however, remains uncertain, and further studies will be required to determine their place in the context of existing conventional and biologic immune-modifying agents.

Treatments for Nail Psoriasis: A Systematic Review by the GRAPPA Nail Psoriasis Work Group

Nail involvement in psoriatic diseases causes significant physical and functional disabilities. Evaluating, measuring, and treating nail involvement is important in improving the health outcomes and quality of life among patients with psoriasis and psoriatic arthritis (PsA). We performed a systematic analysis of the literature on nail psoriasis to help inform an update of treatment recommendations by the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA).

Nail psoriasis: a review of the literature

Nails are considered epidermal appendages, and as such, are commonly affected in patients with psoriasis, 80% of whom are likely to develop nail psoriasis as a result of their condition. Two patterns of nail disorders have been shown to be caused by psoriasis. Nail matrix involvement can result in features such as leukonychia, pitting (punctures or cupuliform depressions), red spots in the lunula and crumbling. Nail bed involvement, on the other hand, can cause onycholysis, salmon or oil-drop patches, subungual hyperkeratosis and splinter hemorrhages. Nail disease causes aesthetic and functional impairment, and is indicative of more severe forms of psoriasis as well as of joint involvement. The treatment for nail psoriasis involves behavioral interventions, topical medications, or systemic therapy in case of extensive skin or joint involvement. This article presents a review of the main features of nail psoriasis, its clinical presentation, diagnostic and assessment methods, clinical repercussions, and of its available treatment options.

A 36-week retrospective open trial comparing the efficacy of biological therapies in nail psoriasis

BACKGROUND

Nail psoriasis occurs in about 50% of psoriatic patients and can be psychologically devastating since it appears on visible areas. Up to now there is no evidence about what biological drugs is the most effective on nail psoriasis.

OBJECTIVES

The aim of our study was to determine if one of the four biological drugs approved in our country (infliximab, adalimumab, etanercept, ustekinumab) is more effective than the others for nail psoriasis.

MATERIALS AND METHODS

A single-center, retrospective study was conducted to assess the efficacy of biological therapies in patients with moderate to severe psoriasis with nail involvement. NAPSI was evaluated in all psoriatic patients. Kruskal-Wallis and Fisher's exact tests were used to analyze the data.

RESULTS

A global statistically significant improvement in mean NAPSI from baseline to 12, 24 and 36 weeks was observed in all patients. At 12 weeks 27.78% of the patients reach NAPSI 75, at 24 weeks 81.48% and at 36 weeks 88.89%. The improvement in nail psoriasis is not significantly different between groups. An improvement in the mean Psoriasis Area and Severity Index score was also achieved

CONCLUSIONS

Biological therapies have shown to ameliorate psoriatic nail lesions. We did not find any statistically significant differences between the four biological drugs investigated.

Secukinumab improves hand, foot and nail lesions in moderate-to-severe plaque psoriasis: subanalysis of a randomized, double-blind, placebo-controlled, regimen-finding phase 2 trial

BACKGROUND

Psoriasis affecting sites such as the hands, feet and nails can be particularly difficult to treat. There are limited data on the efficacy of biological agents to treat these specific localizations.

OBJECTIVE

This analysis of a phase 2 regimen-finding study evaluated the efficacy of secukinumab in subjects with moderate-to-severe psoriasis and non-pustular involvement of the hands, feet and/or nails.

METHODS

Subjects were randomized (1 : 2 : 2 : 1) to one of three subcutaneous secukinumab 150-mg induction regimens [Single (Week 0), Monthly (Weeks 0, 4, 8), Early (Weeks 0, 1, 2, 4)] or placebo. In the subgroup (n = 131) with hand and/or foot psoriasis [baseline 5-point hand/foot Investigator's Global Assessment (IGA) score ≥2], efficacy was assessed as percentage of subjects achieving an IGA response [a score of 0 (clear) or 1 (minimal) and an improvement of ≥2 points on the 5-point hand/foot scale vs. baseline] at Week 12. In the subgroup (n = 304) with fingernail psoriasis (baseline composite score ≥1), efficacy was assessed as mean percentage change from baseline to Week 12 in a composite score.

RESULTS

At Week 12, a markedly higher percentage of subjects with hand and/or foot psoriasis achieved an IGA response with the Early regimen vs. placebo (54.3% vs. 19.2%, P = 0.005). The composite fingernail score improved with the Early and Monthly regimens, but worsened with placebo [percentage mean change from baseline (SE): -19.1% (6.12) and -10.6% (7.06) vs. 14.4% (11.92); P = 0.010 vs. placebo for Early, P = 0.027 for Monthly). Secukinumab was well tolerated.

CONCLUSION

Secukinumab demonstrated a beneficial effect on psoriasis of the hands/feet/nails in this short-term assessment.

Efficacy of adalimumab across subgroups of patients with moderate-to-severe chronic plaque psoriasis of the hands and/or feet: post hoc analysis of REACH

Background

The Randomized Controlled Evaluation of Adalimumab in Treatment of Chronic Plaque Psoriasis of the Hands and Feet (REACH) trial demonstrated that adalimumab was efficacious and well-tolerated for the treatment of hand and/or foot psoriasis through 28 weeks.

Objective

To evaluate the effects of patient baseline characteristics on efficacy of adalimumab treatment of hand and/or foot psoriasis.

Methods

Patients with moderate-to-severe chronic plaque psoriasis of the hands and/or feet were randomized 2: 1 to adalimumab or placebo during the 16 week, double-blind period of REACH. Primary endpoint was percentage of patients achieving Physician’s Global Assessment of the hands and/or feet of clear/almost clear at week 16. Post hoc analyses evaluated effects of baseline patient characteristics on the primary endpoint. Patients with nail psoriasis at baseline were assessed for association of Nail Psoriasis Severity Index (NAPSI) 50 response with efficacy outcomes at week 16.

Results

Seventy-two patients (49 adalimumab: 23 placebo) were analysed. Greater percentages of adalimumab-treated patients achieved the primary endpoint vs. placebo across all subgroups. Among 31 patients with nail psoriasis, a greater percentage of adalimumab-treated patients achieved NAPSI 50 (56.5%) vs. placebo (12.5%) at week 16. In adalimumab-treated patients, greater percentages of NAPSI 50 Responders vs. Non-responders achieved the primary endpoint, and had greater improvements in erythema, scaling, induration and fissuring, Dermatology Life Quality Index, and pain scores.

Conclusions

Adalimumab was efficacious in treating chronic plaque psoriasis of the hands and/or feet over 16 weeks, regardless of baseline characteristics. Marked improvement in nail psoriasis among adalimumab-treated patients correlated with significant improvements in skin disease and patient-reported outcomes.

Challenging regional psoriasis and ustekinumab biotherapy: impact of the patterns of disease

In some patients, psoriasis appears refractory to many treatments, particularly when the disease is confined to some specific body regions. In this respect, palmoplantar psoriasis and palmoplantar pustulosis are possibly related conditions in their immunopathomechanisms involving Il-12, IL-23, and Th17. Nail psoriasis and scalp psoriasis are two other particular psoriasis manifestations. Accordingly, ustekinumab was tested in a few of these patients. The present paper is limited to peer-reviewed case reports. Data were not supported by bioinstrumental assessments and controlled trials. Overall, they are indicative of potential efficacy. The cost-effectiveness and the risk-benefit assessments merit further investigations.