Clinical Implementation of Biologics and Small Molecules in the Treatment of Hidradenitis Suppurativa

Biologic drugs in hidradenitis suppurativa: what does the GP have to know? A narrative review

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease with a profound disease burden. In recent years, the advent of biologic therapies has improved the treatment landscape for patients with moderate to severe HS. In this new therapeutic era, the role of the general practitioner (GP) in HS treatment is becoming more important than ever. This review discusses how to recognize and diagnose HS by detailing common symptoms. HS can also present with multiple comorbidities. The GP's role in screening for and treating these important comorbidities is pivotal. This review highlights the HS treatment landscape, with a specific focus on what the GP can recommend. The three approved biologics for treating HS include adalimumab, secukinumab and bimekizumab; the benefits and concerns of biologics in everyday clinical practice are detailed. In summary, this review serves as a HS management guide for GPs, with a particular focus on the biologic treatment landscape.

Targeted therapy for immune mediated skin diseases. What should a dermatologist know?

BACKGROUND

Molecularly targeted therapies, such as monoclonal antibodies (mAbs) and Janus Kinase inhibitors (JAKis), have emerged as essential tools in the treatment of dermatological diseases. These therapies modulate the immune system through specific signaling pathways, providing effective alternatives to traditional systemic immunosuppressive agents. This review aims to provide an updated summary of targeted immune therapies for inflammatory skin diseases, considering their pathophysiology, efficacy, dosage, and safety profiles.

METHODS

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A systematic search was conducted on PubMed over the past 10 years, focusing on randomized clinical trials, case reports, and case series related to targeted immune therapies in dermatology. Eligibility criteria were applied, and data were extracted from each study, including citation data, study design, and results.

RESULTS

We identified 1360 non-duplicate articles with the initial search strategy. Title and abstract review excluded 1150, while a full-text review excluded an additional 50 articles. The review included 143 studies published between 2012 and 2022, highlighting 39 drugs currently under investigation or in use for managing inflammatory skin diseases.

STUDY LIMITATIONS

The heterogeneity of summarized information limits this review. Some recommendations originated from data from clinical trials, while others relied on retrospective analyses and small case series. Recommendations will likely be updated as new results emerge.

CONCLUSION

Targeted therapies have revolutionized the treatment of chronic skin diseases, offering new options for patients unresponsive to standard treatments. Paradoxical reactions are rarely observed. Further studies are needed to fully understand the mechanisms and nature of these therapies. Overall, targeted immune therapies in dermatology represent a promising development, significantly improving the quality of life for patients with chronic inflammatory skin diseases.

Associations between type 1 diabetes and autoimmune skin diseases: Mendelian randomization analysis

Background

Type 1 diabetes mellitus (T1DM) may be associated with various autoimmune diseases, but the causal relationship between T1DM and autoimmune skin diseases is not yet clear.

Methods

The summary statistical data on T1DM and nine autoimmune skin diseases in European populations were extracted for mendelian randomization (MR) analysis. Subsequently, the analysis was replicated in East Asian populations. In the MR estimation, inverse variance-weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode methods were utilized. Outliers were excluded using MR-PRESSO, and horizontal pleiotropy was assessed with MR-Egger. Additionally, a multivariable MR analysis was conducted to investigate whether T1DM has an independent effect on autoimmune skin diseases after adjusting for potential confounders.

Results

In Europe, the MR estimated based on IVW method indicated a causal association between genetically determined T1DM and systemic lupus erythematosus (SLE) (OR = 1.38, 95%CI: 1.26-1.50, p＜0.01), rheumatoid arthritis (RA) (OR = 1.15, 95%CI: 1.05-1.25, p＜0.01), as well as multiple sclerosis (MS) (OR = 1.17, 95%CI: 1.01-1.36, p = 0.04), but there is no association between T1DM and atopic dermatitis (AD), vitiligo, lichen planus (LP), hidradenitis suppurativa (HS), alopecia areata (AA) and systemic sclerosis (SS). After adjusting for time spent watching television, body mass index, type 2 diabetes mellitus, and body fat percentage, we found a causal relationship between T1DM and SLE (OR = 1.29, 95%CI: 1.16-1.44, p < 0.01), RA (OR = 1.28, 95%CI: 1.20-1.38 p < 0.01) and MS (OR = 1.11, 95%CI: 1.04-1.18, p < 0.01). Then, no genetic causal association was found between TIDM and SLE, and AD in East Asia. These results didn't exhibit horizontal pleiotropy, and "leave-one-out" analysis demonstrated result stability.

Conclusion

Our MR research indicates a causal relationship between T1DM and SLE, RA, and MS in Europe. However, no causal relationship between T1DM and SLE has been observed in East Asia. Therefore, it is important to regularly monitor relevant immunological markers of SLE, RA, and MS in T1DM patients and take preventive measures.

Surgical Management of Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic, relapsing inflammatory disease of the skin, characterized by recurrent draining sinuses and abscesses, predominantly in skin folds carrying terminal hairs and apocrine glands. Treatment for this debilitating disease has been medical management with antibiotics and immune modulators. With the advent of better reconstructive surgical techniques, the role of surgery in the treatment of HS has expanded, from being a last resort to a modality that is deployed earlier. Larger defects can be more easily reconstructed, allowing for a more radical excision of diseased areas. Locoregional flaps, perforator flaps, and propeller flaps that use the fasciocutaneous tissue allow reconstruction of defects with similar tissue, and provide better cosmetic and functional outcomes. They are easy to execute and can be performed even in resource-poor settings with concurrent use of immune modulators and postoperative antibiotics. Hidradenitis can be successfully treated with surgery in early stages as well as severe disease, due to the advances in understanding disease behavior, multidisciplinary care, and advanced reconstructive techniques. Coupled with a multidisciplinary care team, surgery offers a durable, lasting cure for HS, significantly reducing disease morbidity.

Secukinumab for Severe Hidradenitis Suppurativa in a Patient on Haemodialysis: Efficacy and Safety on 300 mg Every 2 Weeks Administration - A Case Report

This case study outlines the management of a 24-year-old male with a history of juvenile nephronophthisis who underwent renal transplantation at age 12 and later required dialysis at 18 due to chronic rejection and hypertension. Subsequently, the patient developed severe Hidradenitis Suppurativa (HS) affecting the axillary, groin, and gluteal regions. Despite undergoing various systemic and intravenous antibiotic therapies, as well as Adalimumab treatment, the HS remained refractory. Adalimumab was discontinued due to a detected ejection fraction of 45% during cardiologic follow-up, likely due to COVID-19 related myocarditis. Following this, the patient was initiated on secukinumab therapy, initially undergoing an induction phase followed by maintenance dosing. Significant improvements were observed in quality of life, pain scores, and HS activity after 5 weeks of secukinumab therapy, with sustained benefits at the 6-month follow-up. Secukinumab was well tolerated, with no reported adverse events. This case underscores the effectiveness and safety of secukinumab as a therapeutic option for refractory HS, particularly in patients with comorbidities such as renal transplant recipients.

Hidradenitis suppurativa as a potential risk factor of periodontitis: a multi-center, propensity-score-matched cohort study

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease associated with systemic symptoms. Periodontitis, a prevalent dental disease, shares immune-mediated inflammatory characteristics with HS. This cohort study aims to evaluate the association between HS and periodontitis. Methods: Using the TriNetX research network, a global-federated database of electronic health records, we conducted a retrospective cohort study. People being diagnosed of HS were identified and propensity score matching was performed to identify proper control group, via balancing critical covariates Within the follow-up time of 1 year, 3 year and 5 years, hazard ratios were calculated to assess the risk of periodontitis in HS patients compared to controls. Results: Within the 53,968 HS patients and the same number of matched controls, the HS patients exhibited a significantly increased risk of developing periodontitis compared to controls after 3 years of follow-up (HR: 1.64, 95% CI: 1.11, 2.44) and 5 years of follow-up (HR: 1.64, 95% CI: 1.21, 2.24) of follow-up. Sensitivity analyses supported these findings under various matching models and washout periods. While comparing with patients with psoriasis, the association between HS and periodontitis remained significant (HR: 1.73, 95% CI: 1.23, 2.44). Conclusion: The observed increased risk suggests the need for heightened awareness and potential interdisciplinary care for individuals with HS to address periodontal health.

Brepocitinib, Zimlovisertib, and Ropsacitinib in Hidradenitis Suppurativa

BACKGROUND: Hidradenitis suppurativa (HS) is a debilitating, inflammatory skin disease with limited treatment options and partially understood pathophysiology. Using an umbrella trial design, three kinase inhibitor immunomodulators with different mechanisms of action were evaluated. METHODS: This phase 2a, double-blind, parallel-group trial enrolled adults with moderate to severe HS who were then randomly assigned (1:1:1:1) to once-daily brepocitinib 45 mg (a JAK1/TYK2 inhibitor), zimlovisertib 400 mg (an IRAK4 inhibitor), ropsacitinib 400 mg (a TYK2 inhibitor), or matching placebo for 16 weeks. The primary end point was the percentage of participants achieving HS clinical response (HiSCR) at week 16. Safety, including treatment-emergent adverse events (TEAEs), was monitored throughout. RESULTS: Totals of 52, 47, 47, and 48 participants were assigned to brepocitinib, zimlovisertib, ropsacitinib, and placebo, respectively. At week 16, 28% were lost to follow-up and assumed to be nonresponders; HiSCR occurred in 33.3% (16/48) of participants receiving placebo and in 51.9% (27/52), 34.0% (16/47), and 37.0% (17/46) of those receiving brepocitinib, zimlovisertib, and ropsacitinib (difference in percentage points vs. placebo [90% confidence interval], 18.7 [2.7 to 34.6], 0.7 [−15.2 to 16.7], and 3.5 [−12.6 to 19.6]), respectively. TEAEs occurred more frequently with active treatment (brepocitinib, 30 [57.7%]; zimlovisertib, 26 [55.3%]; ropsacitinib, 29 [61.7%]; placebo, 23 [47.9%]). Most TEAEs (infections, skin disorders, and gastrointestinal symptoms) were mild; there were no deaths. CONCLUSIONS: Participants with moderate to severe HS treated with brepocitinib experienced greater clinical response, whereas those on zimlovisertib and ropsacitinib did not, compared with placebo. These results favor the JAK/STAT pathway as an immunologic target in HS and did not confirm a role for selective IRAK4 or TYK2 inhibition. These results should be confirmed in larger studies with longer follow-up. (Funded by Pfizer; ClinicalTrials.gov registration number, NCT04092452.)

New treatment of pyoderma gangrenosum and hidradenitis suppurativa: A review

Pyoderma gangrenosum (PG) and hidradenitis suppurativa (HS) are stubborn inflammatory skin diseases categorized as neutrophilic hypodermal dermatoses. These conditions exhibit connections with other autoinflammatory disorders driven by immune responses. Their pathogenesis is complex, rooted in significant imbalances in both innate and adaptive immune systems, particularly featuring elevated levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1, IL-8, IL-17, and IL-23. Studies involving skin tissue pathology and serology have indicated that targeting specific cytokines can bring therapeutic benefits. Indeed, many patients in clinical settings have responded positively to such interventions. Yet, given the diverse cytokines in play, focusing on a single one with antibody therapy might not always be effective. When resistance to biologics emerges, a combined approach targeting multiple overactive cytokines with immunosuppressants, for example cyclosporine and Janus kinase inhibitors, could be an option. In the current review, we explore recent therapeutic developments for PG and HS.

Janus-kinase inhibitors in dermatology: A review of their use in psoriasis, vitiligo, systemic lupus erythematosus, hidradenitis suppurativa, dermatomyositis, lichen planus, lichen planopilaris, sarcoidosis and graft-versus-host disease

Recent studies on molecular pathways have elucidated novel therapeutic approaches in inflammatory and autoimmune skin disorders. Specifically, the dysregulation of the Janus kinase signal transducer and activator of transcription (JAK-STAT) cascade plays a central role in the pathogenesis of many skin conditions. JAK inhibitors, with their ability to selectively target immune responses, are potential treatment options. Using the National Library of Medicine, we provide a comprehensive review of the use of United States Food and Drug Administration (FDA)-approved and emerging JAK or tyrosine kinase 2 (TYK2) inhibitors in a wide range of dermatologic conditions, including psoriasis, vitiligo, systemic lupus erythematosus, hidradenitis suppurativa, dermatomyositis, lichen planus, lichen planopilaris, sarcoidosis and graft-versus-host disease. In patients with psoriasis, oral deucravacitinib (TYK2 inhibitor) has been approved as a once-daily therapy with demonstrated superiority and efficacy over apremilast and placebo and tolerable safety profiles. In patients with vitiligo, topical ruxolitinib (JAK1 inhibitor) is approved as a twice-daily treatment for repigmentation. The efficacy of several other JAK inhibitors has also been demonstrated in several clinical trials and case studies for systemic lupus erythematosus, hidradenitis suppurativa, dermatomyositis, lichen planus, lichen planopilaris, sarcoidosis and graft-versus-host disease. Further investigations with long-term clinical trials are necessary to confirm their utility in treatment and safety for these diseases.

Association between hidradenitis suppurativa and atopic diseases: a multi-center, propensity-score-matched cohort study

Background: Cross-sectional evidence has suggested a high prevalence of atopic diseases in patients with hidradenitis suppurativa (HS). However, there is a lack of evidence based on longitudinal studies. This study aimed to assess the risk of different atopic diseases, including asthma, atopic dermatitis, and allergic rhinitis, in patients with HS. Methods: In this retrospective cohort study, data from the TriNetX research network were obtained. Patients with HS were enrolled, and a 1:1 propensity score matching was performed to select a non-HS control group. Matching covariates included age, sex, race, comorbidities, comedications, socioeconomic status, lab data, and medical utilization status. Hazard ratios (HR) for atopic diseases were assessed. Results: Over a 15-year follow-up period, patients with HS were found to be at a higher risk for atopic dermatitis (HR = 1.65; 95% CI, 1.44-1.90), asthma (HR = 1.41; 95% CI, 1.33-1.49), and allergic rhinitis (HR = 1.08; 95% CI, 1.03-1.13). A similar trend was observed in shorter follow-up periods. The association between HS, atopic dermatitis, and asthma was consistent across different age and sex subgroups. Conclusion: Atopic diseases including atopic dermatitis, asthma and allergic rhinitis are associated with HS. Further investigation is needed to assess the necessity of early screening for atopic diseases in patients with HS.

Use of multiple fasciocutaneous flaps for the management of extensive hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease with a relapsing nature that has a significant impact on the patient's quality of life. The clinical presentation of the disease includes deep dermal abscesses and sinus tracts. Long-term affliction of the disease may lead to contractures, scars and fibrosis. Management is still challenging and varies from medical to surgical options. We report the following case of a man in his 30s who presented with severe HS in the axillae, groins, perineum and lower sacral region. The patient has been treated by excision of the whole lesions followed by using multiple fasciocutaneous flaps as a reconstructive method.

Disease Burden and Treatment Patterns Among US Patients with Hidradenitis Suppurativa: A Retrospective Cohort Study

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, autoinflammatory skin disease associated with many comorbidities. One biologic (adalimumab) is approved for HS. This study assessed the sociodemographic characteristics, comorbidities, treatment patterns, healthcare resource utilization (HCRU) and associated costs of patients with HS following biologic approval.

METHODS

This non-interventional, retrospective cohort study involved adult (≥ 18 years) and adolescent (12-17 years) patients diagnosed with HS in the United States (US) using Optum's de-identified Clinformatics® Data Mart Database during the period 1 January 2016 to 31 December 2018.

RESULTS

Of 42,843 identified patients, 10,909 met the incident HS patient criteria (10,230 adults, 628 adolescents, 51 patients aged <12 years). Patients were mostly diagnosed by a general practitioner/pediatrician (adults: 41.6%; adolescents: 39.6%) or dermatologist (adults: 22.1%; adolescents: 30.6%). Commonly reported Charlson comorbidities at pre-index in adult patients were diabetes without complications (20.4%), chronic pulmonary disease (16.4%) and diabetes with complications (9.0%), and the most frequent Elixhauser comorbidities were uncomplicated hypertension (38.3%), obesity (22.5%), uncomplicated diabetes (19.0%) and depression (17.4%). The burden of comorbidities generally increased over time after diagnosis in both adults and adolescents. HS-related surgical procedures were uncommon in the 2-years post-index period: an incision and drainage procedure was reported in 7.6% of adults and 6.4% of adolescents. Patients were predominantly treated with both topical and systemic antibiotic treatments (adults: 25.0% and 65.1%, respectively; adolescents: 41.7% and 74.5%, respectively). Biologic prescription was higher in adults than adolescents (3.5% vs. 1.8%). Total healthcare costs for adult and adolescent patients in the 2-years post-index period were US$42,143 and US$16,057, respectively, with outpatient costs accounting for the majority of these costs (US$20,980 and US$8408, respectively).

CONCLUSION

In adult and adolescent patients with HS, comorbidity burden continues to increase after diagnosis. All-cause and HS-specific HCRU and costs are high in adults and adolescents with HS. These findings support the need for a multidisciplinary comprehensive care strategy for patients with HS.

Bimekizumab in hidradenitis suppurativa: a valid and effective emerging treatment

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease in which many inflammatory mediators such as interleukin-17 are involved in the pathophysiology. We describe a rapid improvement in the skin lesions of HS in patients with psoriasis treated with bimekizumab.

Narrative Review and Update on Biologic and Small Molecule Drugs for Hidradenitis Suppurativa: An Entity With a Promising Future

Hidradenitis suppurativa (HS) is a chronic inflammatory entity characterized by the appearance of multiple nodules, abscesses, and fistulas, predominantly in apocrine regions. In addition to its dermatological involvement, it is associated with multiple systemic comorbidities. Its treatment is combined: topical pharmacological, systemic pharmacological and surgical. Regarding biologic or small molecule drugs, currently only adalimumab is approved. A narrative review of the literature on biological or small molecule drugs used in the treatment of hidradenitis suppurativa is presented. The arsenal we found is large, with multiple targets: inhibitors of tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-17, IL-23, IL-1, inhibitors of the janus kinase (JAK) pathway, and multiple other drugs in study. New prospective studies and comparative trials are needed to analyze the effectiveness and safety of these treatments, in an entity with a promising future.

Narrative Review and Update on Biologic and Small Molecule Drugs for Hidradenitis Suppurativa: An Entity With a Promising Future

Hidradenitis suppurativa (HS) is a chronic inflammatory entity characterized by the appearance of multiple nodules, abscesses, and fistulas, predominantly in apocrine regions. In addition to its dermatological involvement, it is associated with multiple systemic comorbidities. Its treatment is combined: topical pharmacological, systemic pharmacological and surgical. Regarding biologic or small molecule drugs, currently only adalimumab is approved. A narrative review of the literature on biological or small molecule drugs used in the treatment of hidradenitis suppurativa is presented. The arsenal we found is large, with multiple targets: inhibitors of tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-17, IL-23, IL-1, inhibitors of the janus kinase (JAK) pathway, and multiple other drugs in study. New prospective studies and comparative trials are needed to analyze the effectiveness and safety of these treatments, in an entity with a promising future.

Adalimumab in conjunction with surgery compared with adalimumab monotherapy for hidradenitis suppurativa: A Randomized Controlled Trial in a real-world setting

BACKGROUND

Adalimumab, the only biologic registered for hidradenitis suppurativa, shows clinical response in up to 60% of patients, leaving many patients in need for other treatment options such as surgery.

OBJECTIVE

To compare the clinical effectiveness of adalimumab combined with surgery vs adalimumab monotherapy in patients with moderate to severe hidradenitis suppurativa.

METHODS

A pragmatic Randomized Controlled Trial was performed from August 2018 to July 2022. Primary outcome was the difference in mean International Hidradenitis Suppurativa Severity Score System reduction after 12 months of treatment with the difference in mean Dermatology Life Quality Index reduction as a key secondary outcome.

RESULTS

Thirty-one patients were included per arm. The mean International Hidradenitis Suppurativa Severity Score System at baseline was 23.9 ± 10.7 in the surgery group and 20.9 ± 16.4, in the monotherapy group. After 12 months of treatment the surgery group had a significantly greater reduction in International Hidradenitis Suppurativa Severity Score System compared with the monotherapy group (-19.1 ± 11.3 vs -7.8 ± 11.8, P < .001). Moreover, the surgery group showed a greater reduction in Dermatology Life Quality Index after treatment compared with the monotherapy group (-8.2 ± 6.2 vs -4 ± 7.7, P = .02).

LIMITATIONS

The study follow-up was too short to assess surgical recurrence rates.

DISCUSSION

Combining adalimumab with surgery resulted in greater clinical effectiveness and improved quality of life after 12 months in patients with moderate to severe hidradenitis suppurativa.

Guselkumab for the treatment of patients with moderate-to-severe hidradenitis suppurativa: A phase 2 randomized study

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that causes substantial physical, emotional and psychological burdens. Guselkumab, a monoclonal antibody that binds to the p19 subunit of interleukin-23, has demonstrated high levels of efficacy in the treatment of inflammatory diseases, including psoriasis and psoriatic arthritis.

OBJECTIVE

To evaluate the effect of guselkumab on the treatment of HS, a phase 2, multicentre, randomized, placebo-controlled, double-blind, proof-of-concept study was conducted.

METHODS

Patients ≥18 years of age with moderate-to-severe HS for ≥1 year were randomized to (1) guselkumab 200 mg by subcutaneous (SC) injection every 4 weeks (q4w) through Week 36 (guselkumab SC); (2) guselkumab 1200 mg intravenously (IV) q4w for 12 weeks, then switched to guselkumab 200 mg SC q4w from Weeks 12 through 36 (guselkumab IV); or (3) placebo for 12 weeks, with re-randomization to guselkumab 200 mg SC q4w at Weeks 16 through 36 (placebo → guselkumab 200 mg) or guselkumab 100 mg SC at Weeks 16, 20, 28 and 36 and placebo at Weeks 24 and 32 (placebo → guselkumab 100 mg). End points included HS clinical response (HiSCR) and patient-reported outcomes.

RESULTS

Although guselkumab SC or guselkumab IV resulted in numerically higher HiSCR versus placebo at Week 16 (50.8%, 45.0%, 38.7%, respectively), statistical significance was not achieved. Numerically greater improvements in patient-reported outcomes were also observed for guselkumab SC and guselkumab IV versus placebo at Week 16. Through Week 40, no clear differences to suggest a dose response were observed for HiSCR and patient-reported outcomes.

CONCLUSIONS

Despite modest improvements, the primary end point was not met and the overall findings do not support the efficacy of guselkumab in the treatment of HS.

CLINICALTRIALS

gov: NCT03628924.

Adalimumab-Induced Paradoxical Psoriasis Treated with Biologics Targeting the IL-17/IL-23 Axis in Patients with Hidradenitis Suppurativa

BACKGROUND

Paradoxical psoriasis (PP) has been mainly described in patients receiving tumor necrosis factor-α (TNFα) inhibitors for inflammatory bowel disease or psoriasis vulgaris, while such data in the context of hidradenitis suppurativa (HS) are scarce. The purpose of this study was to demonstrate the course of PP and the underlying HS upon switching from adalimumab to a biologic agent targeting the interleukin (IL)-17/IL-23 axis.

METHODS

The electronic medical database of the outpatient department for HS of a tertiary hospital for skin diseases was searched to identify patients with moderate-to-severe HS under treatment with adalimumab, who developed PP and were switched to biological therapy with an IL-17 or IL-23 inhibitor between February 2016 and January 2022. Disease assessment scores were evaluated at baseline, at time of PP development, as well as six and 12 months thereafter.

RESULTS

Among the 83 patients who received adalimumab for the treatment of HS between February 2016 and January 2022, 10 patients (12%) developed paradoxical psoriasiform skin reactions after a median time of seven (range, 2-48) months. There were four females (40%) and six males (60%) with a median age of 42.5 (range, 33-56) years. Five patients presented with plaque psoriasis and five with palmoplantar pustulosis, while four had intertriginous and three nail involvement. In most of the patients, HS responded well to adalimumab at onset of PP. Eight patients were changed to secukinumab, one to ustekinumab, and one to risankizumab. HS further improved in all but 2 patients, one receiving secukinumab and one receiving risankizumab. In addition, all patients achieved improvement of PP.

CONCLUSION

Despite the small number of patients, this study provides support that patients with adalimumab-induced PP may benefit from biologics targeting the IL-17/IL-23 axis. Further studies are needed to establish the optimal therapeutic strategy of the anti-TNFα-induced PP in the context of HS.

Emerging Treatments and the Clinical Trial Landscape for Hidradenitis Suppurativa Part I: Topical and Systemic Medical Therapies

Hidradenitis suppurativa (HS) is an oftentimes debilitating condition that presents with painful nodules, abscesses, and sinus tracts. This condition is challenging to treat, in part because the pathogenesis of the condition is incompletely understood but also because there are limited therapeutic options. HS research is undergoing explosive growth with multiple new molecular pathways under study, which will hopefully lead to improved disease control for patients. Part I of this review will provide an overview of the emerging topical and systemic therapies under investigation for HS.

Computational Drug Discovery in Ankylosing Spondylitis-Induced Osteoporosis Based on Data Mining and Bioinformatics Analysis

BACKGROUND

Ankylosing spondylitis (AS) and osteoporosis (OP) are both prevalent illnesses in spine surgery, with OP being a possible consequence of AS. However, the mechanism of AS-induced OP (AS-OP) remains unknown, limiting etiologic research and therapy of the illness. To mine targetable medicine for the prevention and treatment of AS-OP, this study analyzes public data sets using bioinformatics to identify genes and biological pathways relevant to AS-OP.

METHODS

First, text mining was used to identify common genes associated with AS and OP, after which functional analysis was carried out. The STRING database and Cytoscape software were used to create protein-protein interaction networks. Hub genes and potential drugs were discovered using drug-gene interaction analysis and transcription factors-gene interaction analysis.

RESULTS

The results of text mining showed 241 genes common to AS and OP, from which 115 key symbols were sorted out by functional analysis. As options for treating AS-OP, protein-protein interaction analysis yielded 20 genes, which may be targeted by 13 medications.

CONCLUSIONS

Carlumab, bermekimab, rilonacept, rilotumumab, and ficlatuzumab were first identified as the potential drugs for the treatment of AS-OP, proving the value of text mining and pathway analysis in drug discovery.

Systemic Antibiotic Therapy in Hidradenitis Suppurativa: A Review on Treatment Landscape and Current Issues

Hidradenitis suppurativa (HS) is a chronic, recurrent, and inflammatory skin disease characterized by painful, deep-seated, nodules, abscesses, and sinus tracts in sensitive areas of the body, including axillary, inguinal, and anogenital regions. Antibiotics represent the first-line pharmacological treatment of HS because of their anti-inflammatory properties and antimicrobial effects. This narrative review summarizes the most significant current issues on the role of systemic antibiotics in the management of HS, critically analyzing the main limits of their use (antibiotic resistance and toxicity). Although, in the last decades, several cytokines have been implicated in the pathomechanism of HS and the research on the use of novel biologic agents in HS has been intensified, antibiotics remain a valid therapeutic approach. Future challenges regarding antibiotic therapy in HS comprise their use in association with biologics in the management of acute flare or as a bridge therapy to surgery.

New Insight into the Molecular Pathomechanism and Immunomodulatory Treatments of Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is an immune-mediated inflammatory disorder characterized by deep-seated nodules, abscesses, sinus tracts and scars localized in the intertriginous areas. It is accompanied by pain, malodourous secretion and a dramatically decreased quality of life. Although the pathogenesis has not been entirely elucidated, the primary event is follicular hyperkeratosis of the pilosebaceous apocrine unit. Since the registration of the tumor necrosis factor-alpha inhibitor Adalimumab in 2015, several cytokines have been implicated in the pathomechanism of HS and the research of novel therapeutic targets has been intensified. We provide an update on the inflammatory cytokines with a central role in HS pathogenesis and the most promising target molecules of future HS management.

Efficacy and Safety of Biologics and Small Molecules for Moderate-to-Severe Hidradenitis Suppurativa: A Systematic Review and Network Meta-Analysis

Background: Treatment of hidradenitis suppurativa (HS) is difficult and current guidelines are based mainly on expert opinion and non-randomized controlled trials. Recently, there have been some targeted therapies using uniform primary endpoints for outcome assessment. Objective: Recommendations can be provided on selecting biologics and targeted synthetic small molecules for refractory HS by comparing the efficacy and safety of these medications. Methods: Databases including ClinicalTrial.gov, Cochrane Library, and PubMed were searched. Randomized controlled trials (RCTs) for moderate-to-severe HS were eligible. We performed random-effect network meta-analysis and ranking probability. The primary outcome was Hidradenitis Suppurativa Clinical Response (HiSCR) at 12-16 weeks. Secondary outcome included Dermatology Life Quality Index (DLQI) 0/1, mean change of DLQI from baseline, and adverse effects. Results: A total of 12 RCTs involving 2915 patients were identified. Adalimumab, bimekizumab, secukinumab 300 mg q4w and secukinumab 300 mg q2w showed superiority to placebo in HiSCR at weeks 12 to 16. In addition, there was no significant difference between bimekizumab and adalimumab as measured by HiSCR (RR = 1.00; 95% CI: 0.66-1.52) and DLQI 0/1 (RR = 2.40, 95% CI: 0.88-6.50). In terms of ranking probability for achieving HiSCR at 12-16 weeks, adalimumab ranked first, followed by bimekizumab, secukinumab 300 mg q4w, and secukinumab 300 mg q2w. All biologics and small molecules did not differ in the development of adverse effects compared to placebo. Conclusions: Adalimumab, bimekizumab, secukinumab 300 mg q4w and secukinumab 300 mg q2w represent four regimens that produce better outcomes than placebo without increased risk of adverse events. Adalimumab and bimekizumab exhibited best HiSCR and DLQI 0/1 between weeks 12-16.

Hidradenitis Suppurativa and JAK Inhibitors: A Review of the Published Literature

Background: Hidradenitis suppurativa (HS), also known as acne inversa or Verneuil's disease, is a chronic, inflammatory, recurrent, and debilitating skin disease of the hair follicles characterized by inflammatory, painful, deep-rooted lesions in the areas of the body characterized by the presence of the apocrine glands. Unfortunately, huge unmet needs still remain for its treatment. Objective: The purpose of our review was collecting all cases, case series, trials, and ongoing studies available in the literature on the use of this class of drugs for HS. Materials and Methods: The investigated manuscripts included trials, reviews, letters to the editor, real-life studies, case series, and reports. Manuscripts were identified, screened, and extracted for the relevant data following the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. Results: We selected 56 articles of which 25 met the selection criteria for our review. Among the JAK inhibitors to date, there is only one published clinical trial in the literature (Janus kinase 1 inhibitor INCB054707), a real-life study with 15 patients up to week 24 in which upadacitinib was used and a case series where tofacitinib was successfully used. Conversely, there are several ongoing clinical trials. Conclusions: Results to date in the literature show promising levels of efficacy and the safety of JAK inhibitors in HS. Several clinical trials are underway from which it will be very important to compare the available data. There are still too few studies conducted with a low sample size, so it remains critical to investigate this issue further in the future with a real-life study involving a large sample of patients in order to provide safe and viable therapeutic alternatives for HS.

Efficacy and Safety of Risankizumab for the Treatment of Hidradenitis Suppurativa: A Phase 2, Randomized, Placebo-Controlled Trial

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, immune-mediated skin condition characterized by inflammatory lesions that can cause pain, impaired physical activity, and reduced quality of life. This study evaluated the efficacy and safety of risankizumab, a humanized immunoglobulin G1 monoclonal antibody that specifically inhibits interleukin 23 by binding to its p19 subunit, for the treatment of HS.

METHODS

This phase II multicenter, randomized, placebo-controlled, double-blind study investigated the efficacy and safety of risankizumab in patients with moderate-to-severe HS. Patients were randomized 1:1:1 to receive subcutaneous risankizumab 180 mg; risankizumab 360 mg; or placebo at weeks 0, 1, 2, 4, and 12. Patients initially randomized to placebo received blinded risankizumab 360 mg at weeks 16, 17, and 18; patients initially randomized to risankizumab received blinded matching placebo at the same time points. From weeks 20-60, all patients received open-label risankizumab 360 mg every 8 weeks. The primary endpoint was the achievement of HS Clinical Response (HiSCR) at week 16. Safety was assessed by monitoring of treatment-emergent adverse events (TEAEs).

RESULTS

A total of 243 patients were randomized (risankizumab 180 mg, n = 80; risankizumab 360 mg, n = 81; placebo, n = 82). HiSCR was achieved by 46.8% of patients with risankizumab 180 mg, 43.4% with risankizumab 360 mg, and 41.5% with placebo at week 16. The primary endpoint was not met, and the study was terminated early. Incidence of TEAEs, severe TEAEs, TEAEs considered possibly related to study drug, and TEAEs leading to discontinuation of study drug were generally low and comparable across treatment groups.

CONCLUSION

Risankizumab does not appear to be an efficacious treatment for moderate-to-severe HS. Future studies to understand the complex molecular mechanisms underlying HS pathogenesis and develop improved therapies are warranted.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03926169.

Patient Preferences in the Management of Hidradenitis Suppurativa: Results of a Multinational Discrete Choice Experiment in Europe

BACKGROUND AND OBJECTIVE

Hidradenitis suppurativa is a chronic inflammatory skin disease that can lead to a substantial reduction in quality of life. Recent studies revealed high levels of unmet care needs of patients with hidradenitis suppurativa, but their preferences in treatment decision making have scarcely been investigated. This study aimed to reveal which treatment attributes adult patients with HS in Europe consider most important in treatment decision-making.

METHODS

A discrete choice experiment was conducted with adult patients with hidradenitis suppurativa in Europe to reveal which treatment attributes are most important when making treatment decisions. Participants were presented with 15 sets of two treatment options and asked for each to choose the treatment they preferred. The treatments were characterized by six attributes informed by a prior literature review and qualitative research: effectiveness, pain reduction, duration of treatment benefit, risk of mild adverse event, risk of serious infection, and mode of administration. A random parameter logit model was used to estimate patients' preferences with additional subgroup and latent class models used to explore any differences in preferences across patient groups.

RESULTS

Two hundred and nineteen adult patients with hidradenitis suppurativa were included in the analysis (90% women, mean age 38 years). For all six treatment attributes, significant differences were observed between levels. Given the range of levels of each attribute, the most important treatment attributes were effectiveness (47.9%), followed by pain reduction (17.3%), annual risk of a mild adverse event (14.4%), annual risk of a serious infection (10.3%), mode of administration (5.3%), and duration of treatment benefit (4.8%). Higher levels of effectiveness, namely a 75% or 100% reduction in the abscess and inflammatory nodule count, were preferred over levels of effectiveness primarily investigated in randomized clinical trials of hidradenitis suppurativa (a 50% reduction). Results were largely consistent across subgroups and three latent class groups were identified.

CONCLUSIONS

This study revealed the most important treatment characteristics for patients with hidradenitis suppurativa that can help inform joint patient-physician decision making in the management of hidradenitis suppurativa. Designing future hidradenitis suppurativa treatments according to stated preferences, namely, to offer higher levels of effectiveness and pain improvement without higher risks of adverse events, may increase patients' treatment concordance and lead to improved disease management outcomes.

Keratinocytes and immune cells in the epidermis are key drivers of inflammation in hidradenitis suppurativa providing a rationale for novel topical therapies

BACKGROUND

Hidradenitis suppurativa (HS) is a debilitating inflammatory skin disease characterized by painful nodules, drainage and scarring in skin folds. Injectable adalimumab is the only drug approved by the US Food and Drug Administration for the treatment of HS. Although systemic Janus kinase (JAK) inhibitors show promise, serious side-effects have been reported. There are no highly effective topical treatments for HS; furthermore, the contribution of epidermal keratinocytes to the intense inflammation has largely been unexplored.

OBJECTIVES

We investigated the role of keratinocytes and epidermal immune cells in HS inflammation at all Hurley stages of disease severity. We aimed to determine whether ruxolitinib can mitigate inflammation from keratinocytes and to develop a better understanding of how topical therapeutics might benefit patients with HS.

METHODS

We used skin samples from 87 patients with HS (Hurley stages I-III) and 39 healthy controls to compare keratinocyte- and immune cell-driven epidermal inflammation, in addition to the response of lesional HS keratinocytes to treatment with interferon (IFN)-γ and ruxolitinib. We used haematoxylin and eosin staining, immunohistochemistry, immunoblotting and quantitative reverse-transcription polymerase chain reaction assessments in whole skin, isolated epidermis, and cultured keratinocytes from healthy controls and both nonlesional and lesional HS skin to identify and define epidermal and keratinocyte-mediated inflammation in HS and how this may be targeted by therapeutics.

RESULTS

HS lesional keratinocytes autonomously secreted high levels of chemokines, such as CCL2, CCL3 and CXCL3, which recruited neutrophils, CD8 T cells, and natural killer cells to the epidermis. Keratinocytes were the dominant source of tumour necrosis factor-α and interleukin (IL)-6 in HS lesions with little to no contribution from underlying dermal immune cells. In the presence of IFN-γ, which is dependent on immune cell infiltrate in vivo, keratinocytes expressed increased levels of additional cytokines including IL-1β, IL-12, IL-23 and IL-36γ. The JAK inhibitor ruxolitinib mitigated the expression of inflammatory cytokines and chemokines in HS lesional keratinocytes, thus providing a rationale for future study as a topical treatment for HS.

CONCLUSIONS

This study demonstrates that keratinocytes actively recruit immune cells to HS epidermis and interactions between these cells drive a broad inflammatory profile in HS epidermis. Targeting epidermal inflammation in HS with novel topical formulations may be highly efficacious with reduced systemic side-effects.

Outcomes and Reliability of Perforator Flaps in the Reconstruction of Hidradenitis Suppurativa Defects: A Systemic Review and Meta-Analysis

INTRODUCTION

Hidradenitis suppurativa (HS) is a common and debilitating disease, in which the only effective treatment involves a wide excision of the affected skin. Secondary wound healing and skin grafting are two well-known options for managing these defects, but perforator flaps provide a new therapeutic alternative by ensuring reconstructions of large defects, reducing donor site morbidity, and enhancing functional recovery. The aim of this study was to achieve a systematic review of perforator flaps use in HS.

PATIENTS AND METHODS

PubMed and Cochrane databases were searched from 1989 to 2021. The PRISMA statement was used in the study selection process and the review was registered on PROSPERO. Furthermore, patient characteristics, operative technique, complications, and recurrences were searched.

RESULTS

Thirty-six articles were selected including 286 patients and 387 flaps. Axillary localization was mostly represented (83.2%). Direct donor site closure was achieved in 99.1% of cases. In total, 15.1% of the flaps presented at least one of the following complications: wound dehiscence (5.5%), partial necrosis (2.9%), hematoma or seroma (2.1%), infection (2.1%), venous congestion (1.8%), and nerve injury (0.3%). Two cases of total necrosis were recorded. Recurrence of the disease was observed in 2.7% of the defects.

CONCLUSIONS

Pedicled perforator flaps are a reliable and reproducible technique in the reconstruction of HS defects. They are associated with a low recurrence rate while ensuring an effective reconstruction with reduced morbidity and faster recovery compared to the techniques classically used in this indication.

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.

Targeting mitochondria in dermatological therapy: Beyond oxidative damage and skin aging

INTRODUCTION

The analysis of the role of the mitochondria in oxidative damage and skin aging is a significant aspect of dermatological research. Mitochondria generate most reactive oxygen species (ROS); however, excessive ROS are cytotoxic and DNA-damaging and promote (photo-)aging. ROS also possesses key physiological and regulatory functions and mitochondrial dysfunction is prominent in several skin diseases including skin cancers. Although many standard dermatotherapeutics modulate mitochondrial function, dermatological therapy rarely targets the mitochondria. Accordingly, there is a rationale for "mitochondrial dermatology"-based approaches to be applied to therapeutic research.

AREAS COVERED

This paper examines the functions of mitochondria in cutaneous physiology beyond energy (ATP) and ROS production. Keratinocyte differentiation and epidermal barrier maintenance, appendage morphogenesis and homeostasis, photoaging and skin cancer are considered. Based on related PubMed search results, the paper evaluates thyroid hormones, glucocorticoids, Vitamin D3 derivatives, retinoids, cannabinoid receptor agonists, PPARγ agonists, thyrotropin, and thyrotropin-releasing hormone as instructive lead compounds. Moreover, the mitochondrial protein MPZL3 as a promising new drug target for future "mitochondrial dermatology" is highlighted.

EXPERT OPINION

Future dermatological therapeutic research should have a mitochondrial medicine emphasis. Focusing on selected lead agents, protein targets, in silico drug design, and model diseases will fertilize a mito-centric approach.