Adalimumab for the treatment of hidradenitis suppurativa/acne inversa

S2k‐Leitlinie zur Therapie der Hidradenitis suppurativa/Acne inversa – Kurzfassung

Die S2k‐Leitlinie der Hidradenitis suppurativa/Acne inversa (HS/AI) soll eine akzeptierte Entscheidungshilfe für die Auswahl/Durchführung einer geeigneten/suffizienten Therapie liefern. Hidradenitis suppurativa/Acne inversa ist eine chronisch‐rezidivierende, entzündliche, potenziell mutilierende Hauterkrankung des terminalen Haartalgdrüsenapparats, mit schmerzhaften, entzündlichen Läsionen in den apokrinen drüsenreichen Körperregionen. Ihre Punktprävalenz in Deutschland ist 0,3%, sie wird mit einer Verspätung von 10,0 ± 9,6 Jahren diagnostiziert. Abnormale Differenzierung der Keratinozyten des Haartalgdrüsenapparats und eine begleitende Entzündung bilden die zentrale pathogenetische Grundlage. Primäre HS/AI‐Läsionen sind entzündliche Knoten, Abszesse und drainierende Tunnel. Rezidive in den letzten 6 Monaten mit mindestens zwei Läsionen an den Prädilektionsstellen verweisen auf eine HS/AI mit einer 97‐prozentigen Genauigkeit. HS/AI‐Patienten leiden an einer deutlichen Einschränkung der Lebensqualität. Zur korrekten Therapieentscheidung sollen Klassifikation und Aktivitätsbewertung mit einem validierten Instrument erfolgen, wie dem International Hidradenitis Suppurativa Severity Scoring System (IHS4). Hidradenitis suppurativa/Acne inversa wird nach der Ausprägung der nachweisbaren Entzündung in zwei Formen eingeteilt: aktive, entzündliche (milde, mittelschwere und schwere nach IHS4) und vorwiegend inaktive, nicht entzündliche (Hurley‐Grad‐I, ‐II und ‐III) HS/AI. Orale Tetrazykline oder eine 5‐tägige intravenöse Therapie mit Clindamycin sind mit der Effektivität von Clindamycin/Rifampicin vergleichbar. Subkutan applizierbares Adalimumab, Secukinumab und Bimekizumab sind für die Therapie der HS/AI zugelassen. Für die vorwiegend nicht entzündliche Erkrankungsform stehen verschiedene operative Verfahren zur Verfügung. Medikamentöse/chirurgische Kombinationen gelten als ganzheitliches Therapieverfahren.

S2k guideline for the treatment of hidradenitis suppurativa / acne inversa - Short version

The S2k guideline on hidradenitis suppurativa/acne inversa (HS/AI) aims to provide an accepted decision aid for the selection/implementation of appropriate/sufficient therapy. HS/AI is a chronic recurrent, inflammatory, potentially mutilating skin disease of the terminal hair follicle-glandular apparatus, with painful, inflammatory lesions in the apocrine gland-rich regions of the body. Its point prevalence in Germany is 0.3%, it is diagnosed with a delay of 10.0 ± 9.6 years. Abnormal differentiation of the keratinocytes of the hair follicle-gland apparatus and accompanying inflammation form the central pathogenetic basis. Primary HS/AI lesions are inflammatory nodules, abscesses and draining tunnels. Recurrences in the last 6 months with at least 2 lesions at the predilection sites point to HS/AI with a 97% accuracy. HS/AI patients suffer from a significant reduction in quality of life. For correct treatment decisions, classification and activity assessment should be done with a validated tool, such as the International Hidradenitis Suppurativa Severity Scoring System (IHS4). HS/AI is classified into two forms according to the degree of detectable inflammation: active, inflammatory (mild, moderate, and severe according to IHS4) and predominantly inactive, non-inflammatory (Hurley grade I, II and III) HS/AI. Oral tetracyclines or 5-day intravenous therapy with clindamycin are equal to the effectiveness of clindamycin/rifampicin. Subcutaneously administered adalimumab, secukinumab and bimekizumab are approved for the therapy of HS/AI. Various surgical procedures are available for the predominantly non-inflammatory disease form. Drug/surgical combinations are considered a holistic therapy method.

Secukinumab in patients with moderate-to-severe hidradenitis suppurativa based on prior biologic exposure: an efficacy and safety analysis from the SUNSHINE and SUNRISE phase III trials

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease associated with a substantial disease burden. Secukinumab has previously been reported to have sustained efficacy with a favourable safety profile in patients with moderate-to-severe HS. It is unknown whether prior biologic exposure affects the efficacy and safety of secukinumab.

OBJECTIVES

To investigate the efficacy and safety of secukinumab in patients with moderate-to-severe HS based on prior exposure to -biologics.

METHODS

This was an analysis of the SUNSHINE and SUNRISE phase III trials of secukinumab in patients with moderate-to-severe HS. Patients were randomized at baseline to receive secukinumab every 2 (SECQ2W) or 4 weeks (SECQ4W), or placebo for 16 weeks. After week 16, patients on the SECQ2W and SECQ4W schedules remained on the same treatment regimen, while patients randomized to placebo were switched to either SECQ2W or SECQ4W up to week 52. Assessments based on prior exposure to biologics included Hidradenitis Suppurativa Clinical Response (HiSCR), abscess and inflammatory nodule (AN) count, flare rates, HS-related pain [numerical rating scale 30 (NRS30)], 55% reduction in the International Hidradenitis Suppurativa Severity Score System (IHS4-55), Dermatology Life Quality Index, EuroQol-5D and safety.

RESULTS

Overall, 1084 patients were randomized in the SUNSHINE and SUNRISE trials and included in this analysis; 255 (23.5%) were biologic-experienced [SECQ2W (n = 80); SECQ4W (n = 81); placebo (n = 94)] and 829 (76.5%) were biologic-naïve [SECQ2W (n = 281); SECQ4W (n = 279); placebo (n = 269)]. At week 16, responses were more efficacious for secukinumab than for placebo with regard to HiSCR in patients who were biologic-experienced {SECQ2W 37.0% [odds ratio (OR) 1.60, 95% confidence interval (CI) 0.83-3.08]; SECQ4W 38.8% [OR 1.67, 95% CI 0.86-3.22]; placebo 27.3%} and biologic-naïve [SECQ2W 45.6% (OR 1.64, 95% CI 1.15-2.33); SECQ4W 45.4% (OR 1.61, 95% CI 1.13-2.29); placebo 34.2%]. Similar results were observed for AN count, NRS30 and IHS4-55. The higher response seen at week 16 with secukinumab was sustained, with a trend toward improvement over time, through to week 52 in both subgroups. Additional efficacy was observed for quality-of-life assessments, and no differences in safety between subgroups were observed.

CONCLUSIONS

Regardless of prior biologic exposure, secukinumab was efficacious in improving the signs and symptoms of HS. This finding positions secukinumab as the first option in patients who are biologic-naïve, as well as in patients who have previously been treated with other biologic therapy, based on individual patient needs.

Case report: Acne vulgaris treatment with 5-Aminolaevulinic acid photodynamic therapy and adalimumab: a novel approach

Acne vulgaris is a common skin condition that affects a large proportion of teenagers and young adults. Despite the availability of various treatment options, many patients experience inadequate relief or intolerable side effects. Photodynamic therapy (PDT) is a growing interest in the treatment of acne vulgaris, with 5-Aminolaevulinic acid (ALA) being one of the most commonly used photosensitizers. Adalimumab is a biologic medication used to treat inflammatory skin conditions such as Psoriasis and Hidradenitis suppurativa (HS), which targets TNF-α. Combining different therapies, such as ALA-PDT and adalimumab, can often provide more effective and longer-lasting results. This report presents the case of a patient with severe and refractory acne vulgaris who was treated with a combination of ALA-PDT and adalimumab, resulting in significant improvement in the condition. The literature review highlights the significant comorbidity associated with acne, emphasizing the need for potential of TNF-α inhibitors for its effective treatments that address physical symptoms and ALA-PDT is known to treat scar hyperplasia, and to prevent or minimize the formation of post-acne hypertrophic scars. The combination of TNF inhibitors and ALA-PDT or adalimumab has shown promising results in treating inflammatory skin conditions, including severe and refractory acne vulgaris, as per recent studies.

HS 3D-SeboSkin Model Enables the Preclinical Exploration of Therapeutic Candidates for Hidradenitis Suppurativa/Acne Inversa

Despite the rapid development in hidradenitis suppurativa (HS) research, the immediate introduction of potent therapeutic compounds in clinical trials and the lack of definitive outcome measures have led to the discontinuation of potential therapeutic compound studies. HS is a solely human disease, and therefore, the search for preclinical human models has been given priority. The 3D-SeboSkin model, a co-culture of human skin explants with human SZ95 sebocytes as a feeder layer, has been shown to prevent the rapid degeneration of human skin in culture and has been validated for HS preclinical studies. In this work, the HS 3D-SeboSkin model has been employed to characterize cellular and molecular effects of the EMA- and FDA-approved biologic adalimumab. Adalimumab, a tumor necrosis factor-α inhibitor, was shown to target inflammatory cells present in HS lesions, inducing a prominent anti-inflammatory response and contributing to tissue regeneration through a wound healing mechanism. Adalimumab inhibited the lesional tissue expression of TNF-α, IL-3, IL-15, and MCP-3 and downregulated the secretion of IL-1α, IL-5, RANTES, MCP-2, TNF-α, TNF-β, TGF-β, and IFN-γ. In contrast, IL-6 was stimulated. The compound failed to modify abnormal epithelial cell differentiation present in the HS lesions. Patients with Hurley stage II lesions exhibited stronger expression of autophagy proteins in perilesional than in lesional skin. Adalimumab modified the levels of the pro-apoptotic proteins LC3A, LC3B, and p62 in an individual, patient-dependent manner. Finally, adalimumab did not modify the NFκB signal proteins in SZ95 sebocytes and NHK-19 keratinocytes, used to study this specific pathway. The administration of the validated HS 3D-SeboSkin model in ex vivo studies prior to clinical trials could elucidate the individual pathogenetic targets of therapeutic candidates and, therefore, increase the success rates of clinical studies, minimizing HS drug development costs.

Real-World Findings on the Characteristics and Treatment Exposures of Patients with Hidradenitis Suppurativa from US Claims Data

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, debilitating, and painful inflammatory skin disease that significantly and negatively impacts patients' quality of life. The prevalence of HS in the USA is estimated to be 0.10%, with worldwide reports suggesting a prevalence closer to 1%. There is limited real-world evidence available on the care of patients with HS. We aimed to evaluate the trends in clinical care and treatment in the patient population with HS in the USA in a real-world setting.

METHODS

A cohort study was conducted using claims data from IBM MarketScan Databases, including the US Commercial Claims and Encounters with Medicare Supplemental and Coordination of Benefits (CCAE+MDCR) database and IBM US Medicaid database.

RESULTS

The annual prevalence of HS increased from 0.06% (2008) to 0.14% (2017), and from 0.17% (2008) to 0.31% (2017) among CCAE+MDCR and Medicaid patients, respectively. Dermatologist visits increased from 31.9% (2008) to 47.8% (2019) in CCAE+MDCR patients, and decreased from 10.9% (2008) to 8.5% (2018) in Medicaid patients. Opioid use decreased from 45.4% (2008) to 25.5% (2019) among CCAE+MDCR patients, and from 71.3% (2008) to 48.1% (2018) among Medicaid patients. Only 8.4% of CCAE+MDCR patients and 5.8% of Medicaid patients were exposed to any biologic in 2018.

CONCLUSIONS

Improved care and treatment of HS over the last decade, including the emergence of new treatments, have been accompanied by an increase in awareness and reported prevalence of the disease. However, there are still gaps in access to dermatologic care and low utilization of biologic therapies among patients with HS. INFOGRAPHIC.

Overview and comparison of the clinical scores in hidradenitis suppurativa: A real-life clinical data

Introduction

Partly due to its clinical heterogeneity, hidradenitis suppurativa (HS) is difficult to score accurately; illustrated by the large number of disease scores. In 2016, a systematic review by Ingram et al. reported the use of about thirty scores, and since then, this number has increased further. Our aim is twofold: to provide a succinct but detailed narrative review of the scores used to date, and to compare these scores with each other for individual patients.

Materials and methods

The review of the literature was done among articles in English and French, on Google, Google scholar, Pubmed, ScienceDirect and Cochrane. To illustrate the differences between scores, data from some Belgian patients included in the European Registry for HS were selected. A first series of patients compares the severity of the following scores: Hurley, Hurley Staging refined, three versions of Sartorius score (2003, 2007, 2009), Hidradenitis Suppurativa Physician Global Assessment (HS-PGA), International Hidradenitis Suppurativa Severity Scoring System (IHS4), Severity Assessment of Hidradenitis Suppurativa (SAHS), Hidradenitis Suppurativa Severity Index (HSSI), Acne Inversa Severity Index (AISI), the Static Metascore, and one score that is not specific to HS: Dermatology Life Quality Index (DLQI). A second set of patients illustrates how some scores change over time and with treatment: Hurley, Hurley Staging refined, Sartorius 2003, Sartorius 2007, HS-PGA, IHS4, SAHS, AISI, Hidradenitis Suppurativa Clinical Response (HiSCR), the very new iHS4-55, the Dynamic Metascore, and DLQI.

Results

Nineteen scores are detailed in this overview. We illustrate that for some patients, the scores do not predictably and consistently correlate with each other, either in an evaluation of the severity at a time-point t, or in the evaluation of the response to a treatment. Some patients in this cohort may be considered responders according to some scores, but non-responders according to others. The clinical heterogeneity of the disease, represented by its many phenotypes, seems partly to explain this difference.

Conclusion

These examples illustrate how the choice of a score can lead to different interpretations of the response to a treatment, or even potentially change the results of a randomized clinical trial.

Switching from Adalimumab Originator to Biosimilar in Patients with Hidradenitis Suppurativa Results in Losses of Response—Data from the German HS Registry HSBest

Since 2021, adalimumab biosimilar ABP 501 can be used alternatively to adalimumab originator (ADAO) in the treatment of hidradenitis suppurativa (HS). Effectiveness and safety data remain scarce. We investigated the impact of switching from ADAO to ABP 501 on disease severity and the occurrence of adverse events (AEs) in patients with HS. We analyzed clinical data on patients enrolled in the German HSBest registry. Evaluation outcomes were assessed at three time points (baseline of originator (t0), prior to switching to biosimilar (t1) and 12 to 14 weeks after switching (t2)) and included patient-reported AEs and disease severity using the International Hidradenitis Suppurativa Severity Score System (IHS4) score. In total, 94 patients were switched from ADAO to ABP 501. Overall, 33.3% (n = 31/94) of the patients developed AEs and/or loss of response (LoR) within 12 to 14 weeks after switching. Of these, 61.3% (n = 19/31) experienced LoR but no AEs, 22.6% (n = 7/31) LoR combined with AEs and 16.1% (n = 5/31) AEs only. Our study showed that switching HS patients from ADAO to ABP 501 does significantly affect treatment effectiveness. Switching patients who are on remission maintenance therapy should be viewed critically.

New and Emerging Targeted Therapies for Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic, recurrent, inflammatory skin disease deriving from the hair follicles. The formation of inflammatory nodules, abscesses, fistulas, and sinus tracts is characterized by a large inflow of key pro-inflammatory mediators, such as IFN-γ, TNF-α, IL-1, IL-17, and IL-12/23. Adalimumab is currently the only Food and Drug Administration (FDA)- and European Medicines Agency (EMA)-approved biologic therapy for moderate to severe HS in adults and adolescents. However, the long-term effectiveness of this TNF-α inhibitor in HS patients has shown to be highly variable. This review aims to review the evidence for emerging therapies that target the main pro-inflammatory cytokines in HS pathogenesis. A review of the literature was conducted, using the PubMed and Google Scholar repositories, as well as Clinicaltrials.gov. Presently, the most promising biologics in phase III trials are anti-IL-17 antibodies, secukinumab, and bimekizumab. Furthermore, an anti-IL-1 biologic, bermekimab, is currently in phase II trials, and shows encouraging results. Overall, the clinical efficacies of all new targeted therapies published up to this point are limited. More studies need to be performed to clarify the precise molecular pathology, and assess the efficacy of biological therapies for HS.

New approaches in management and treatment of 'Hidradenitis suppurativa'

Background / Aim: Hidradenitis suppurativa (HS) is a chronic inflammatory disease that most often affects apocrine gland-bearing areas of the skin. The treatment depends on the severity of the clinical presentation. The paper objective was to present new modalities in management and treatment of HS. Methods: The subjects in this research included the patients suffering from the severe form of HS, who were treated in the University Clinical Centre of the Republic of Srpska for the past three years. The effect of treatment of HS were monitored. In four patients, biologic therapy with adalimumab or adalimumab biosimilars was administered, while four patients received radiotherapy and 17 of them, were treated surgically. Depending on the type of treatment, the effects of therapy were monitored after 6-12 weeks by using clinical examination and by assessing the disease stage according to the Hurley staging. Due to a small number of subjects, especially in patients treated with biologic and radiotherapy, it was not possible to perform any statistical analysis and the results were presented by description, in tables and photographs. Results: Biologic therapy: Adalimumab was administered subcutaneously 80 mg, twice a month. After 12 weeks, in 4 patients was observed a regression of changes by 60-70 % when compared to previous skin changes. Radiotherapy: the total radiation dose was 5 Gy, distributed in 5 or 10 fractions. After 12 weeks an improvement by 60-70 % was observed. Surgical treatment: after 6-8 weeks, the patients were fully recovered. Conclusions: Application of biologic and radiotherapy after 12 weeks had similar results, ie it brought to regression of changes by 60-70 %. The best results were achieved after surgical treatment of HS.

Hidradenitis Suppurativa and Comorbid Disorder Biomarkers, Druggable Genes, New Drugs and Drug Repurposing-A Molecular Meta-Analysis

Chronic inflammation and dysregulated epithelial differentiation, especially of hair follicle keratinocytes, have been suggested as the major pathogenetic pathways of hidradenitis suppurativa/acne inversa (HS). On the other hand, obesity and metabolic syndrome have additionally been considered as an important risk factor. With adalimumab, a drug has already been approved and numerous other compounds are in advanced-stage clinical studies. A systematic review was conducted to detect and corroborate HS pathogenetic mechanisms at the molecular level and identify HS molecular markers. The obtained data were used to confirm studied and off-label administered drugs and to identify additional compounds for drug repurposing. A robust, strongly associated group of HS biomarkers was detected. The triad of HS pathogenesis, namely upregulated inflammation, altered epithelial differentiation and dysregulated metabolism/hormone signaling was confirmed, the molecular association of HS with certain comorbid disorders, such as inflammatory bowel disease, arthritis, type I diabetes mellitus and lipids/atherosclerosis/adipogenesis was verified and common biomarkers were identified. The molecular suitability of compounds in clinical studies was confirmed and 31 potential HS repurposing drugs, among them 10 drugs already launched for other disorders, were detected. This systematic review provides evidence for the importance of molecular studies to advance the knowledge regarding pathogenesis, future treatment and biomarker-supported clinical course follow-up in HS.

Efficacy and Safety of Bimekizumab in Moderate to Severe Hidradenitis Suppurativa: A Phase 2, Double-blind, Placebo-Controlled Randomized Clinical Trial

Question

What is the efficacy and safety of bimekizumab in individuals with moderate to severe hidradenitis suppurativa (HS)?

Findings

In this double-blind, placebo-controlled, phase 2 randomized clinical trial including 90 randomized patients with HS (73 completed the trial), bimekizumab demonstrated clinically meaningful and consistent improvements in participants with HS vs placebo across all assessed outcome measures. Serious adverse events occurred in 2 of 46 bimekizumab-treated participants (4%) and 2 of 21 placebo-treated participants (10%).

Meaning

These initial clinical efficacy and safety data suggest that dual inhibition of interleukin 17A and 17F by bimekizumab may be a viable treatment approach for HS, with the potential to achieve deep responses in clinical outcome measures, and support further evaluation.

Importance

Hidradenitis suppurativa (HS) is a chronic inflammatory disease with a high burden for patients and limited existing therapeutic options.

Objective

To evaluate the efficacy and safety of bimekizumab, a monoclonal IgG1 antibody that selectively inhibits interleukin 17A and 17F in individuals with moderate to severe HS.

Design, Setting, and Participants

This phase 2, double-blind, placebo-controlled randomized clinical trial with an active reference arm was performed from September 22, 2017, to February 21, 2019. The study included a 2- to 4-week screening period, a 12-week treatment period, and a 20-week safety follow-up. Of 167 participants screened at multiple centers, 90 were enrolled. Eligible participants were 18 to 70 years of age with a diagnosis of moderate to severe HS 12 months or more before baseline.

Interventions

Participants with HS were randomized 2:1:1 to receive bimekizumab (640 mg at week 0, 320 mg every 2 weeks), placebo, or reference arm adalimumab (160 mg at week 0, 80 mg at week 2, and 40 mg every week for weeks 4-10).

Main Outcomes and Measures

The prespecified primary efficacy variable was the proportion of participants with a 50% or greater reduction from baseline in the total abscess and inflammatory nodule count with no increase in abscess or draining fistula count (Hidradenitis Suppurativa Clinical Response [HiSCR] at week 12. Exploratory variables included proportion achieving a modified HiSCR with 75% reduction of HiSCR criteria (HiSCR₇₅) or a modified HiSCR with 90% reduction of HiSCR criteria (HiSCR₉₀), change in Patient’s Global Assessment of Pain, and Dermatology Life Quality Index total scores.

Results

Eighty-eight participants received at least 1 dose of study medication (61 [69%] female; median age, 36 years; range, 18-69 years). Seventy-three participants completed the study, including safety follow-up. Bimekizumab demonstrated a higher HiSCR rate vs placebo at week 12 (57.3% vs 26.1%; posterior probability of superiority equaled 0.998, calculated using bayesian analysis). Bimekizumab demonstrated greater clinical improvements compared with placebo. Improvements in the International Hidradenitis Suppurativa Severity Score (IHS4) were seen at week 12 with bimekizumab (mean [SD] IHS4, 16.0 [18.0]) compared with placebo (mean [SD] IHS4, 40.2 [32.6]). More bimekizumab-treated participants achieved positive results on stringent outcome measures compared with placebo. At week 12, 46% of bimekizumab-treated participants achieved HiSCR₇₅ and 32% achieved HiSCR₉₀, whereas 10% of placebo-treated participants achieved HiSCR₇₅ and none achieved HiSCR₉₀; in adalimumab-treated participants, 35% achieved HiSCR₇₅ and 15% achieved HiSCR₉₀. One participant withdrew because of adverse events. Serious adverse events occurred in 2 of 46 bimekizumab-treated participants (4%), 2 of 21 placebo-treated participants (10%), and 1 of 21 adalimumab-treated participants (5%).

Conclusions and Relevance

In this phase 2 randomized clinical trial, bimekizumab demonstrated clinically meaningful improvements across all outcome measures, including stringent outcomes. Bimekizumab’s safety profile was consistent with studies of other indications, supporting further evaluation in participants with HS.

Trial Registration

ClinicalTrials.gov Identifier: NCT03248531

Anti-COVID-19 measurements for hidradenitis suppurativa patients

The reported incidence of COVID‐19 among cohorts of patients with inflammatory bowel and skin diseases under treatment with biologicals is low. Treatment may further modify disease severity as some biological modifiers, such as anakinra, are also proposed for the management of COVID‐19 patients potentially providing HS patients with an advantage.

The above preliminary evidence suggests that hidradenitis suppurativa (HS) does probably not provide an increased susceptibility for COVID‐19 and that any susceptibility is unlikely to be modified negatively by treatment with biologicals.

On the occasion of its 10th International Conference, experts of the European Hidradenitis Suppurativa Foundation e.V. have prepared a consensus statement regarding anti‐COVID‐19 measurements for HS patients. Based on the available knowledge, patients with HS may be vaccinated against SARS‐CoV2 and patients affected by metabolic syndrome constitute a high‐risk group for COVID‐19 and should be vaccinated at the earliest convenient point in time. HS patients on treatment with adalimumab can be vaccinated with non‐living virus anti‐SARS‐CoV2 vaccines. A possible suboptimal effect of the vaccine may be suspected but might not be expected universally. The management of the biological treatment in HS patients is at the discretion of the dermatologist / responsible physician.

Target molecules for future hidradenitis suppurativa treatment

The registration of the tumour necrosis factor-α inhibitor adalimumab in 2015 was a major step forward in the treatment of hidradenitis suppurativa/acne inversa (HS). However, it soon became evident that the effectiveness of adalimumab in daily practice was highly variable. A significant unmet medical need of HS patients remained, and the search for novel therapeutic targets was intensified. During the 10th European Hidradenitis Suppurativa Foundation (EHSF) e.V. Conference, reknown international HS investigators virtually presented and discussed the published data on these potential target molecules for future HS treatment. This article addresses the most promising molecules currently under investigation from a pathophysiological and clinical point of view. With phase III trials ongoing, the anti- interleukin (IL)-17 biologics bimekizumab and secukinumab are in the most advanced stage of clinical development showing promising results. In addition, targeting IL-1α with bermekimab has shown encouraging results in two clinical trials. Directing treatment at neutrophil recruitment and activation by targeting IL-36 with spesolimab fits well in the pathogenic concept of HS and clinical phase II trial results are pending. In contrast to in situ evidence, Complement 5a (C5a) and C5a receptor blockade have only shown greater clinical benefit in patients with severe HS. Inhibition of Janus kinase (JAK) 1 signalling in HS showed clinical efficacy only in the highest dosage, highlighting that careful surveillance of the balance between safety and efficacy of JAK inhibition is warranted. Overall, clinical efficacies of all novel treatments reported so far are modest. To guide drug development, more and better-defined translational data on the pathogenesis of this severe and enigmatic inflammatory skin disease are required.

Phenotypes and Pathophysiology of Syndromic Hidradenitis Suppurativa: Different Faces of the Same Disease? A Systematic Review

<b><i>Background:</i></b> There is growing evidence that (certain) hidradenitis suppurativa (HS) comorbidities comprise syndromes including HS as a key cutaneous manifestation. These apparently autoinflammatory syndromes and their diagnostic delay might have detrimental effects on affected patients. <b><i>Methods:</i></b> A systematic review was performed on the databases MEDLINE, EMBASE, and CENTRAL utilizing a standardized extraction form according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. <b><i>Results:</i></b> Sixty-four eligible articles on syndromic HS were retrieved. The identified syndromes included already described ones (pyoderma gangrenosum-acne-suppurative hidradenitis, pyogenic arthritis-pyoderma gangrenosum-acne-suppurative hidradenitis, psoriatic arthritis-pyoderma gangrenosum-acne-suppurative hidradenitis, pyoderma gangrenosum-acne vulgaris-hidradenitis suppurativa-ankylosing spondylitis, synovitis-acne-pustulosis-hyperostosis-osteitis) and further novel symptom constellations. Cutaneous signs, including HS lesions, usually precede signs from other organs. The cutaneous signs of a considerable proportion of patients appear refractory to conventional treatment, and monotherapy with biologics does not suffice to sustain remission. <b><i>Conclusion:</i></b> The results are subsequently discussed with focus on the pathophysiology and treatment of the detected syndromes. The dermatologist’s role in the precise diagnosis and early treatment administration of HS is pivotal. The purpose of the treatment should be the effective prevention or delay of the autoinflammatory march and its irreversible consequences.

Biologics for hidradenitis suppurativa: an update

Hidradenitis suppurativa (HS) is a chronic, inflammatory dermatosis characterized by an occurrence of nodules, abscesses, sinus tracks and scarring. Its pathogenesis is multifactorial and still not fully understood, therefore, current systemic therapies still remain a serious challenge. Increased levels of several proinflammatory cytokines have been reported in patients suffering from HS, therefore biologics appear as a new approach to therapy for this condition. Adalimumab is the only one internationally registered agent and should be considered first after the conventional therapies appear insufficient. The efficacy and safety profile of some preparations, like infliximab and etanercept was confirmed so far in randomized trials, but there are some new biologics which are still being evaluated and require more rigorous examination.

Adalimumab Dose Intensification in Recalcitrant Hidradenitis Suppurativa/Acne Inversa

BACKGROUND

Adalimumab is the only approved compound for the treatment of adult patients with moderate-to-severe hidradenitis suppurativa (HS) who did not respond to a systemic classical treatment. Despite its significant short- and long-term efficacy, a percentage of patients do not respond sufficiently. Moreover, some primary responders experience a response loss with time.

OBJECTIVE

To analyse the effectiveness of adalimumab dose intensification in HS patients.

METHODS

A case series of adalimumab 80 mg/week subcutaneously (s.c.) compassionate use in patients with HS, who did not respond sufficiently or in primary responders with progressive response loss to the registered adalimumab dose of 40 mg/week s.c. Patients were collected and evaluated retrospectively. Patients' data were extracted from medical records.

RESULTS

The 14 patients collected were Caucasian with HS of Hurley stage II-III and moderate or severe International HS Severity Score System (IHS4) stage. Adalimumab dose intensification significantly improved IHS4 score, Pain Index, HS-Physician Global Assessment, pain, and Cardiff Dermatology Life Quality Index. Two young female patients with HS and Crohn's disease developed psoriatic lesions during the treatment with adalimumab 80 mg/week s.c.

CONCLUSION

An enhanced level of effectiveness was assessed in the majority of the HS patients treated with adalimumab dose intensification (80 mg/week s.c.). Larger studies are required to evaluate this observation.

Biologic Treatment for Hidradenitis Suppurativa

Patients with hidradenitis suppurativa (HS) are often undertreated and there are limited efficacious therapies available for treating this population. Biologics are an emerging therapeutic modality used in the management of many inflammatory conditions including HS. Implementation of biologics is typically reserved for moderate-to-severe cases or in those cases that are refractory to treatment. Though many biologics have been trialed for use in HS, only one biologic, adalimumab, is currently US FDA (Food and Drug Administration) approved for the treatment of moderate-to-severe HS. Limitations in the use of biologics for HS include the many scoring systems utilized in research studies and the relatively few well-designed, adequately powered clinical trials.

Pathogenetic Characteristics of Mesenchymal Stem Cells in Hidradenitis Suppurativa

Importance

Hidradenitis suppurativa (HS) is a disease of the terminal hair follicle in apocrine gland-enriched skin areas, where immunobiology dysregulation of mesenchymal stem cells (MSCs) may have a key role.

Objective

To investigate the MSC profile in patients with HS and in healthy controls.

Design, Setting, and Participants

In this prospective case-control study, patients with HS were recruited from the Dermatological Clinic at the Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, Ancona, Italy. Biopsy specimens were analyzed at the Histology Section of the Department of Clinical and Molecular Sciences. Participants included 11 patients with HS and 9 healthy controls, who were recruited into the study between January 20, 2015, and September 20, 2016, and underwent punch biopsy from axillary skin. None of the participants had received any antibiotics (systemic or topical therapy) within almost 12 weeks before the study.

Main Outcomes and Measures

The immunophenotypic profile of MSCs was characterized following the minimal criteria established by the International Society for Cellular Therapy for the identification of MSCs. Levels of 12 cytokines belonging to helper T-cell subtypes 1, 2, and 17 pathways were examined on the secretome of isolated cells by enzyme-linked immunoabsorbent assay.

Results

Skin MSCs were characterized in 11 patients with HS (8 women and 3 men; mean [SD] age, 35.8 [7.9] years) and 9 healthy controls (7 women and 2 men; mean [SD] age, 36.7 [6.9] years). The healthy controls were matched with patients with HS for body mass index. Mesenchymal stem cells isolated from patients with HS (HS-MSCs) and from healthy controls (C-MSCs) met the International Society for Cellular Therapy minimal criteria. Compared with C-MSCs, cytokine analyses of HS-MSCs revealed statistically significant overexpression of interleukin (IL) 6 (median [interquartile range {IQR}], 8765.00 [7659.00-9123.00] vs 2849.00 [2609.00-3001.00] pg/mL; P = .008), IL-10 (median [IQR], 29.46 [26.35-35.79] vs 21.36 [19.89-23.33] pg/mL; P = .004), IL-12 (median [IQR], 15.25 [13.27-16.25] vs 11.89 [10.73-12.33] pg/mL; P = .03), IL-17A (median [IQR], 15.24 [13.23-17.24] vs 11.24 [10.28-11.95] pg/mL; P = .008), tumor necrosis factor (median [IQR], 42.54 [42.20-43.94] vs 32.55 [31.78-33.28] pg/mL; P = .004), transforming growth factor β1 (median [IQR], 1728.00 [1535.00-1979.00] vs 500.80 [465.00-634.50] pg/mL; P = .004), and interferon γ (median [IQR], 11.49 [10.71-12.35] vs 9.45 [9.29-10.01] pg/mL; P = .005).

Conclusions and Relevance

Mesenchymal stem cells isolated from the skin of patients with HS seem to be activated toward an inflammatory status. The imbalance between proinflammatory and anti-inflammatory activities of MSCs favors the hypothesis of their pathogenic involvement in HS.

T helper 17 cell/regulatory T-cell imbalance in hidradenitis suppurativa/acne inversa: the link to hair follicle dissection, obesity, smoking and autoimmune comorbidities

BACKGROUND

Disintegration of the infundibula of terminal hair follicles (HFs) in intertriginous skin areas exhibits the histological hallmark of hidradenitis suppurativa (HS)/acne inversa, featuring a dissecting terminal hair folliculitis. Elevated serum levels of interleukin (IL)-17 and local increase in the ratio of proinflammatory T helper (Th)17 cells and anti-inflammatory regulatory T cells (Tregs) have been reported. Perifollicular Tregs play a key role in HF stem cell homeostasis and infundibular integrity.

OBJECTIVES

In this review, we evaluate the Th17/Treg ratio in HS, its aggravating conditions and associated comorbidities. Furthermore, we intended to clarify whether drugs with reported beneficial effects in the treatment of HS readjust the deviated Th17/Treg axis.

METHODS

PubMed-listed, peer-reviewed original research articles characterizing Th17/Treg regulation in HS/acne inversa and associated comorbidities were selected for this review.

RESULTS

This review presents HS as a disease that exhibits an increased Th17/Treg ratio. Perifollicular deficiencies in Treg numbers or function may disturb HF stem cell homeostasis, initiating infundibular dissection of terminal HFs and perifollicular inflammation. The Th17/Treg imbalance is aggravated by obesity, smoking and decreased Notch signalling. In addition, HS-associated autoimmune diseases exhibit a disturbed Th17/Treg axis resulting in a Th17-dominant state. All drugs that have beneficial effects in the treatment of HS normalize the Th17/Treg ratio.

CONCLUSIONS

HS immunopathogenesis is closely related to deviations of the Th17/Treg balance, which may negatively affect Treg-controlled HF stem cell homeostasis and infundibular integrity. Pharmacological intervention should not only attenuate Th17/IL-17 signalling, but should also improve Treg function in order to stabilize HF stem cell homeostasis and infundibular integrity.

Long-term adalimumab efficacy in patients with moderate-to-severe hidradenitis suppurativa/acne inversa: 3-year results of a phase 3 open-label extension study

BACKGROUND

The optimal long-term dosing strategy for adalimumab (ADA) in hidradenitis suppurativa/acne inversa (HS) was evaluated by pooling the results of the PIONEER phase 3 trials and an open-label extension (OLE) study.

OBJECTIVE

To assess the response to and tolerability of long-term administration of ADA in HS.

METHODS

The durations of the PIONEER I/II periods A, B, and OLE were 12, 24, and 52 or more weeks, respectively. Patients who entered the OLE and received ADA (40 mg every week continuously) and responders plus partial responders (PRRs) were evaluated. Primary efficacy assessments included measurement of HS clinical response (HiSCR), lesion counts, skin pain, and Dermatology Life Quality Index (DLQI). Treatment-emergent adverse events were assessed.

RESULTS

At week 12, 52.3% of those receiving ADA weekly and 73.0% of PRRs achieved HiSCR. Achievement of HiSCR was maintained through week 168 in 52.3% of patients who received ADA weekly and 57.1% of PRRs. Sustained improvement in lesion counts, skin pain, and DLQI score were also observed. The safety profile throughout the OLE was similar to the profiles observed in the PIONEER studies.

LIMITATIONS

The OLE was uncontrolled.

CONCLUSION

Continuous weekly dosing with ADA, 40 mg, is a reasonable treatment option for long-term control of moderate-to-severe HS.

Clinical Signs, Pathophysiology and Management of Cutaneous Side Effects of Anti-Tumor Necrosis Factor Agents

Approximately one in four patients treated with anti-TNF agents (infliximab, etanercept, adalimumab, certolizumab, and golimumab) develops cutaneous adverse events, typically months to years after the initiation of treatment, with xerosis cutis, eczema (often psoriasiform), psoriasis, palmoplantar pustulosis, cutaneous infections, alopecia, and skin cancer being the most frequently encountered. The typical skin lesion of anti-tumor necrosis factor (TNF)-treated patients is orange-red psoriasiform eczema affecting the flexures, genitalia, scalp, or face, with high susceptibility to bacterial superinfection with Staphylococcus aureus. When adequate dermatological treatment is administered to patients with skin lesions receiving anti-TNF treatment, the discontinuation of anti-TNF agents is only rarely required. Smoking, female sex, and Crohn's disease are most frequently observed as risk factors for anti-TNF-induced cutaneous adverse events. The underlying pathophysiology is still poorly understood, but epidermal permeability barrier dysfunction, increased susceptibility to bacterial superinfection, and cytokines derived from T helper (Th) 1 (interferon-γ), Th17 cells (interleukin [IL]-17A and IL-22), plasmocytic dendritic cells (interferon-α), and keratinocytes (IL-36γ and IL-17C) appear to play a role. In this review, we describe the clinical characteristics, risk factors, pathophysiology, and management of cutaneous adverse events of patients treated with anti-TNF agents. In addition, we try to give some practical guidance on how to prevent and manage the skin changes in anti-TNF-treated patients, based on our own experience with dermatological care in a large cohort of inflammatory bowel disease patients receiving anti-TNF therapy.