Janus kinase 1 inhibitor INCB054707 for patients with moderate-to-severe hidradenitis suppurativa: results from two phase 2 studies

European S2k guidelines for hidradenitis suppurativa/acne inversa part 2: Treatment

INTRODUCTION

This second part of the S2k guidelines is an update of the 2015 S1 European guidelines.

OBJECTIVE

These guidelines aim to provide an accepted decision aid for the selection, implementation and assessment of appropriate and sufficient therapy for patients with hidradenitis suppurativa/acne inversa (HS).

METHODS

The chapters have been selected after a Delphi procedure among the experts/authors. Certain passages have been adopted without changes from the previous version. Potential treatment complications are not included, being beyond the scope of these guidelines.

RESULTS

Since the S1 guidelines publication, validation of new therapeutic approaches has almost completely overhauled the knowledge in the field of HS treatment. Inflammatory nodules/abscesses/draining tunnels are the primary lesions, which enable the classification of the disease severity by new validated tools. In relation to the degree of detectable inflammation, HS is classified into the inflammatory and the predominantly non-inflammatory forms. While the intensity of the inflammatory form can be subdivided by the IHS4 classification in mild, moderate and severe HS and is treated by medication accordingly, the decision on surgical treatment of the predominantly non-inflammatory form is based on the Hurley stage of the affected localization. The effectiveness of oral tetracyclines as an alternative to the oral combination of clindamycin/rifampicin should be noted. The duration of systemic antibiotic therapy can be shortened by a 5-day intravenous clindamycin treatment. Adalimumab, secukinumab and bimekizumab subcutaneous administration has been approved by the EMA for the treatment of moderate-to-severe HS. Various surgical procedures are available for the predominantly non-inflammatory form of the disease. The combination of a medical therapy to reduce inflammation with a surgical procedure to remove irreversible tissue damage is currently considered a holistic therapeutic approach.

CONCLUSIONS

Suitable therapeutic options while considering HS severity in the therapeutic algorithm according to standardized criteria are aimed at ensuring a proper therapy.

Pilot study of topical ruxolitinib demonstrates efficacy and blunting of heterogeneous inflammatory processes in mild hidradenitis suppurativa

BACKGROUND

Therapeutic options for mild hidradenitis suppurativa (HS) represent a significant gap in the current treatment landscape, with no U.S. Food and Drug Administration-approved therapies for early-stage HS. Topical Janus kinase (JAK) inhibitors (JAKi) are a compelling option due to the known upregulation of inflammatory JAK signalling in HS lesions and the recent success of systemic JAKi for the treatment of moderate-to-severe HS.

OBJECTIVES

To assess the clinical efficacy of ruxolitinib in a pilot cohort and to investigate the underlying biologic mechanisms associated with clinical response.

METHODS

This was a pilot single-site open-label prospective 24-week clinical trial of topical ruxolitinib (NCT04414514). Men and women with mild HS (Hurley stage I or II), with active inflammatory nodules, were recruited. All participants were observed for 8 weeks to monitor lesion counts (observational phase); active therapy (treatment phase) was then administered for 16 weeks. Topical ruxolitinib 1.5% cream was applied twice daily, covering the entirety of each HS-affected body site. Clinician- and patient-reported outcome measures were recorded throughout the study. Lesional skin punch biopsies were taken at the start and end of treatment for downstream mechanistic RNA sequencing and histological analyses.

RESULTS

Ten participants were enrolled in the study; four dropped out before the treatment phase of the trial. Six individuals with Hurley stage I (no tunnels) HS completed the study, five of whom successfully achieved Hidradenitis Suppurativa Clinical Response (HiSCR50) through 16 weeks of therapy. In this interim analysis, differential gene expression and gene set enrichment analyses revealed reduced activation of JAK-dependent interferon, interleukin (IL)-6, IL-2 and epidermal growth factor receptor signalling, and antimicrobial and keratinocyte responses. In contrast, signatures of wound healing and lipid metabolism were increased following JAKi treatment, indicating a return to homeostasis. Histological analyses revealed that clinically responsive patients had significantly reduced epidermal and dermal inflammation. Affected inflammatory infiltrate included neutrophils, T cells and plasma cells, with the predominantly affected cell types specific to the patient.

CONCLUSIONS

Collectively, the broad activity of topical ruxolitinib on inflammatory signalling processes resulted in promising efficacy, even with heterogeneity in baseline inflammation, in this pilot cohort. Importantly, topical treatment not only resolved epidermal inflammation, but also cleared deeper inflammatory infiltrate. The observed efficacy provides rationale to further investigate topical JAKi and other novel topical treatments in HS.

Comprehensive and Updated Algorithm of Hidradenitis Suppurativa Management from the Experts

Management of hidradenitis suppurativa (HS) can be challenging and often requires a multimodal approach with use of on- and off-label medications. There has been a rapid expansion of available HS treatments in the years since the 2019 North American HS (NAHS) clinical management guidelines. Herein we present an up-to-date practical management algorithm based on the diagnosis and management strategies set forth by the 2019 NAHS guidelines using newly available literature. Evaluation and diagnosis of HS disease involves assessment of severity, extent of disease, and impact on patient quality of life. Initial diagnosis of HS should be shortly followed by comorbidity screening. The multimodal approach to HS treatment typically involves use of treatment stacking of topical therapies, systemic and topical antibiotics, retinoids, hormonal and metabolic therapies, biologics and small molecule inhibitors, systemic immunosuppressants, surgical treatment, pain management, lifestyle modifications, adjunctive treatment, wound care, and flare therapy. Thus, the proposed algorithm aims to guide clinicians in their implementation of treatment stacking in HS.

Future Directions and Pipeline Therapies for Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a painful, autoinflammatory condition with dramaticimpact on quality of life. As of January 1, 2024, there are 25 phase I-III clinical trials for topical and systematic medications in the management of HS. Only three medications, adalimumab, secukinumab and bemikizumab, are currently approved by the United States Food and Drug Administration for the treatment of moderate to severe HS. In addition, 15 nonmedication-based studies are ongoing, including those for various surgical techniques, botulinum toxin, laser and light-based therapies, differing wound care methods, and a variety of complementary and alternative medicine practices for HS.

North American clinical practice guidelines for the medical management of hidradenitis suppurativa in special patient populations

BACKGROUND

Hidradenitis suppurativa (HS) affects different patient populations that require unique considerations in their management. However, no HS guidelines for these populations exist.

OBJECTIVE

To provide evidence-based consensus recommendations for patients with HS in 7 special patient populations: (i) pregnancy, (ii) breastfeeding, (iii) pediatrics, (iv) malignancy, (v) tuberculosis infection, (vi) hepatitis B or C infection, and (vii) HIV disease.

METHODS

Recommendations were developed using the Grading of Recommendations Assessment, Development, and Evaluation system to ascertain level of evidence and selected through a modified Delphi consensus process.

RESULTS

One hundred eighteen expert consensus statements are provided for the management of patients with HS across these 7 special patient populations.

The Successful Use of Upadacitinib as Monotherapy for Hidradenitis Suppurativa and Ulcerative Colitis in the Setting of Refractory Disease

Hidradenitis suppurativa (HS) and ulcerative colitis (UC) are associated chronic inflammatory conditions with complex disease courses and potential for overlapping therapeutic management. We describe a case of severe pediatric HS and UC that were poorly controlled despite several standard-of-care therapies, including infliximab and ustekinumab. Transitioning the patient to upadacitinib monotherapy resulted in clinical improvement of both her UC and HS within 3 months, and she was then able to be weaned off her other systemic therapies. While upadacitinib is not currently FDA-approved for HS or pediatric UC, this case report shows promise for upadacitinib monotherapy for both of these complex inflammatory disorders.

Janus-kinase inhibitor use in immune-mediated inflammatory diseases beyond licensed indications: A scoping review

INTRODUCTION

The use of Janus kinase inhibitors (JAKis) in immune-mediated inflammatory diseases (IMIDs) beyond licence is expanding rapidly. The aim of this scoping review was to identify and present the available evidence on the efficacy of JAKis in all conditions without marketing authorisation.

METHODS

Through a systematic literature search we identified studies including 5 or more patients that assessed the use of any JAKi for any efficacy outcome. Quantitative analyses in the form of pairwise meta-analyses were performed for eligible data from randomised controlled trials (RCTs) only.

RESULTS

Eighty-three (n = 83) studies in total were included in our review, assessing efficacy of JAKis in 34 IMIDs. In most conditions, JAKis exhibited generally positive effects, though the majority of evidence came from observational, non-comparative studies. Pairwise meta-analyses were possible for hidradenitis suppurativa and systemic lupus erythematosus (SLE). For hidradenitis suppurativa, we found a clear benefit of treatment with JAKis compared with placebo in achieving clinical response [OR 2.35, 95 % CI (1.24 to 4.46)]. For treatment-resistant SLE, the results were equivocal; JAKi showed some benefit over placebo but statistical significance was only reached for one of the two meta-analysed outcome measures [SLE Responder Index 4, OR 1.41, 95 % CI (1.01 to 1.98); SLE Disease Activity Index 2000; OR 1.36, 95 % CI (0.99 to 1.88)].

CONCLUSIONS

There is a rapidly increasing use of JAKis beyond current licencing in most IMIDs. Large comparative trials are necessary to confirm efficacy and guide future licencing decisions.

Efficacy of Janus kinase inhibitors in immune-mediated inflammatory diseases-a systematic literature review informing the 2024 update of an international expert consensus statement

OBJECTIVE

This systematic literature review (SLR) on efficacy outcomes was performed to inform the 2024 update of the expert consensus statement on the treatment of immune-mediated inflammatory diseases (IMIDs) with Janus kinase inhibitors (JAKi).

METHODS

An update of the 2019 SLR was performed in MEDLINE, Embase, and the Cochrane Library. For efficacy, randomised, placebo (PLC)- or active-controlled trials on all JAKi investigated in IMIDs, as well as cohort and claims data for conditions where such studies were not available, were included.

RESULTS

In total, 10,556 records were screened, and 182 articles were included in the final analysis, investigating 21 JAKi in 51 IMIDs. Forty-three phase 2 and 59 phase 3 trials as well as 9 strategic trials and 72 pilot or cohort studies and case series were considered. JAKi demonstrated efficacy both in PLC-controlled trials as well as in head-to-head comparisons against active comparators, with 93 of 102 randomised controlled trials (RCTs) meeting their primary endpoints. Since 2019, 8 JAKi have received approval by the Federal Drug Agency and the European Medicine Agency for treatment of 11 IMIDs; of these, for 2, no approved disease-modifying antirheumatic drug (DMARD) therapy had previously been available.

CONCLUSIONS

JAKi are effective for treating IMIDs, and various compounds have recently been approved. The impact of Janus kinase (JAK) selectivity for distinct JAK-STAT pathways needs further investigation, and few data are also available on sustained disease control upon tapering or withdrawal or on the optimal strategic placement of JAKi in international treatment algorithms.

Improvements in moderate-to-severe hidradenitis suppurativa with upadacitinib: Results from a phase 2, randomized, placebo-controlled study

BACKGROUND

Hidradenitis suppurativa is a disabling inflammatory skin disease.

OBJECTIVE

To investigate the efficacy and safety of upadacitinib, a selective Janus kinase inhibitor.

METHODS

In this phase 2, randomized, placebo-controlled, double-blind clinical trial (NCT04430855), adults with moderate-to-severe hidradenitis suppurativa were randomized 2:1 to once-daily upadacitinib 30 mg or placebo. At 12 weeks, placebo patients switched to blinded upadacitinib 15 mg, and patients receiving upadacitinib 30 mg continued assigned treatment through week 48. The primary endpoint was ≥50% reduction in total abscess and inflammatory nodule count with no increase in abscess or draining fistula count relative to baseline (Hidradenitis Suppurativa Clinical Response [HiSCR50]) at week 12.

RESULTS

Forty-seven patients received upadacitinib; 21 patients received placebo. At week 12, a significantly greater proportion of patients receiving upadacitinib achieved HiSCR50 vs a prespecified historical placebo rate (38.3% vs 25.0%; 1-sided P = .018). Comparison with the in-trial placebo group showed an adjusted difference of 14.7% (nominal P = .087). HiSCR50 achievement with upadacitinib was consistent across baseline Hurley stage and prior tumor necrosis factor inhibitor exposure and maintained through week 40. Upadacitinib's safety profile was consistent with previous reports on dermatologic conditions.

LIMITATIONS

Sample size was small.

CONCLUSION

Findings support further investigation of upadacitinib for moderate-to-severe hidradenitis suppurativa.

Innovations in Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition characterized by painful, recurrent abscesses, inflammatory nodules, and draining tunnels. Biologic and small molecule therapeutics are effective for treatment of moderate-to-severe HS. The field of HS is rapidly growing with numerous ongoing clinical trials exploring novel agents. This review highlights the latest discoveries in the field of HS, with a particular focus on novel therapeutic agents and procedural management.

Infection risk with JAK inhibitors in dermatoses: a meta-analysis

Evolving evidence suggests that Janus Kinase Inhibitors (JAKi) may predispose to certain infections, including tuberculosis and human herpes viruses. This review aimed to compare the infection risk in patients on a systemic JAKi for a dermatologic indication to a placebo. A systematic review was carried out from inception to June 2023, using the EMBASE, Medline, SCOPUS, and Cochrane Library of Registered Trials databases. Eligible studies included placebo-controlled randomized trials that investigated the incidence of infection in patients with a dermatologic indication. Primary outcomes included the most commonly reported infections pertaining to serious and opportunistic infections, upper respiratory tract infections, nasopharyngitis, herpes simplex, varicella zoster, tuberculosis, neutropenia, and lymphopenia. A meta-analysis of incidence ratios was conducted to determine odds ratios (OR), with a 95% confidence interval (CI) analysis. The meta-analysis found no increased risk of serious (OR: 0.92, 95% CI: 0.61-1.43, P = 0.74) or opportunistic infections (OR: 0.65, 95% CI: 0.32-1.31, P = 0.23). The incidence of varicella-zoster infections was significantly higher in the JAKi cohort (OR: 1.72, 95% CI: 1.08-2.72, P = 0.022). From 25 studies, there was no overall increased risk of herpes simplex infections (OR: 1.43, 95% CI: 0.93-2.23, P = 0.102) to placebo; however, a significantly higher risk in those with atopic dermatitis to alopecia areata was demonstrated (OR: 1.73, 95% CI: 1.13-2.69, P = 0.013). The results of this analysis do not suggest an increased risk of serious and opportunistic infections in those on JAKi compared to placebo. However, they support an increased risk of varicella-zoster infections and a higher risk of herpes simplex infections in those with atopic dermatitis to alopecia areata. The results of this report support these agents' short-term safety but signal that vigilance should be practiced in patients at risk for serious or recurrent herpes virus infections.

Hidradenitis Suppurativa: A Review of the Biologic and Small Molecule Immunomodulatory Treatments

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease that presents as painful, deep-seated nodules, sinus tracts, and abscesses in about 1% of the population. Although the pathogenesis of HS is not perfectly understood, it is generally recognized to be caused by a combination of genetic, endocrine, environmental, and microbiological factors. The treatment principles of HS focus on decreasing the microbial load with antibiotics and/or modulating the host immune response to reduce inflammation. The treatment of adults with moderate-to-severe HS has significantly changed recently with the development of new biological medications and immunomodulators. While previously the mainstay of treatment of moderate-to-severe HS was adalimumab, a biologic tumour necrosis factor α inhibitor, the evidence for the use of other treatment classes such as interleukin (IL)-17 inhibitors, IL-1 inhibitors, and Janus kinase inhibitors has been growing. The goal of this review article is to review the available evidence that supports the efficacy and safety of biologics and small molecule immunomodulator treatments to treat adults with moderate-to-severe HS.

Selective small molecule inhibitors for hidradenitis suppurativa: Today and tomorrow

Hidradenitis suppurativa (HS) is an autoinflammatory condition characterized by abscesses, inflammatory nodules, and tunnels in intertriginous sites of the body. The pathogenesis of HS involves follicular occlusion in combination with environmental, genetic, hormonal, and metabolic factors. HS lesions are characterized by an influx of neutrophils, histiocytes, B and T cells, and upregulation of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1, interleukin-17, and interferons. Selective small molecule inhibitors (SMIs) are organic compounds that bind to active sites on target proteins involved in inflammatory signaling pathways, most commonly blocking enzymes, ion channels and receptors. SMIs are divided into conventional and selective SMIs. Selective SMIs are further subdivided into kinase and nonkinase SMIs. Currently there are five selective SMIs available in the United States with demonstrated efficacy for HS in clinical studies including apremilast, topical ruxolitinib, upadacitinib, fostamatinib, and sirolimus. These selective SMIs target four pathways hypothesized to be important to HS pathogenesis including phosphodiestase 4, Janus kinases, spleen tyrosine kinase, and mammalian target of rapamycin. Several new SMIs are currently in the clinical trial pipeline targeting Bruton's tyrosine kinase, aryl hydrocarbon receptors, heat shock protein 90 as well as interleukin-1 and -17 signaling pathways.

Quantitative analysis of JAK/STAT signaling pathway in patients of inflammatory skin disorders

BACKGROUND

Inflammatory skin diseases (ISDs), are characterized by dysregulated activation of innate and adaptive immune systems, with inflammatory cytokines playing a crucial role in their pathogenesis.

OBJECTIVES

This study aimed to investigate the involvement of Janus kinase/signal transduction and activator of transcription (JAK/STAT) signaling pathway in the pathogenesis of ISDs.

METHODS

The study analyzed a total of 117 skin biopsies, comprising 31 from pyoderma gangrenosum (PG), 25 from hidradenitis suppurativa (HS), 35 from psoriasis patients, and 26 from control subjects. To assess the expression levels of JAK/STAT pathway components, immunohistochemical staining was performed on both the dermal and epidermal layers of the skin. The Histo score (H score) was utilized as the immunoexpression score to evaluate the staining intensity.

RESULTS

The results indicated that all components of the JAK/STAT signaling pathway, except JAK2 and STAT6 in PG, JAK1, STAT4, and STAT6 in HS, and JAK1 in psoriasis, were overexpressed in the dermal skin compared to the control group (p < 0.05). Psoriatic skin had higher expression of STAT6 than both PG and HS and higher expression of JAK2 than PG (p < 0.05). Additionally, HS biopsies had higher expression of JAK2 and STAT6 compared to PG (p < 0.05). JAK1 expression was higher in PG than in HS, psoriasis, and the control group (mean H score was 265.8, 184.8, 191.4, and 113.1, p < 0.05, respectively).

CONCLUSIONS

This study provides new insights into the potential contribution of the JAK/STAT pathway to the pathogenesis of ISDs. The findings suggest that targeting this pathway could be a promising therapeutic strategy for treating these disorders.

[Janus kinase inhibitors for skin disorders]

Immune factors such as interferon‑ɣ and interleukin 4 belong to the group of cytokines that are dependent on type I/II receptors for their signal transmission. Upon activation, these receptors transmit their signal to the cell nucleus and, thus, modulate gene transcription via a signaling cascade consisting of Janus kinases (JAK). This family of four kinases (JAK 1, JAK 2, JAK 3, and tyrosine kinase 2 (TYK2)) subsequently activate members of the signal transducer and activator of transcription (STAT). This finding turned the JAK/STAT signaling pathway into a pharmacological target for the treatment of inflammatory diseases in which cytokines using type I/II receptors play a pathogenic role. In 2018, the European Medicines Agency (EMA) approved tofacitinib for the treatment of psoriatic arthritis. This was the first approval of a JAK/STAT pathway inhibitor for patients treated by dermatologists and rheumatologists. Since then, several new JAK inhibitors have been approved for dermatologic diseases such as atopic dermatitis, alopecia areata, vitiligo, and plaque-type psoriasis. In addition, JAK inhibitors are being investigated for the treatment of many other skin diseases. Thus, systemic JAK inhibitors complete the spectrum of immunotherapeutics with a broader immunological approach compared to monoclonal antibodies. The low molecular weight of JAK inhibitors enables the preparation of these drugs for both systemic and topical administration. Their utilization could represent a valuable alternative to topical steroids. The safety profile of JAK inhibitors must be taken into account. Possible long-term effects may become apparent in the next few years. This article describes both approved JAK inhibitors and relevant new JAK inhibitors that are promising candidates for approval as therapeutics in dermatology.

Hidradenitis Suppurativa: New Targets and Emerging Treatments

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that can be challenging to treat. Biologics and targeted small molecules have become an increasingly popular area of investigation for therapeutic development for moderate-to-severe HS, though only three biologics-adalimumab, secukinumab, and bimekizumab-have received US Food and Drug Administration (FDA) or European Medicines Evaluation Agency approval for treating HS. Promising agents under investigation are targeting interleukin 17A/F, JAK/STAT pathway, interleukin 36, interleukin 1, and more.

Essentials of hidradenitis suppurativa: a comprehensive review of diagnostic and treatment perspectives

Hidradenitis suppurativa, or acne inversa, is a chronic inflammatory skin condition with recurrent inflammatory nodules, abscesses, subcutaneous tracts, and scars. This condition may cause severe psychological distress and reduce the quality of life for affected individuals. It is considered to have one of the most damaging effects on quality of life of any skin disorder as a result of the discomfort and foul-smelling discharge from these lesions. Although the pathophysiology of HS is still unclear, multiple factors, including lifestyle, genetic, and hormonal factors, have been associated with it. The pathogenesis of HS is very complex and has wide clinical manifestations; thus, it is quite challenging to manage and often requires the use of combination treatments that must be tailored according to disease severity and other patient-specific factors. Although lifestyle changes, weight loss, quitting smoking, topical treatments, and oral antibiotics are adequate for mild cases, the challenge for healthcare professionals is dealing with moderate-to-severe HS, which often does not respond well to traditional approaches. This literature review, consisting of an overview of the various assessment tools and therapy strategies available for the diagnosis and treatment of HS from published literature, aims to be a guide for practicing clinicians in dealing with the complexities associated with this disease.

The use of biologics and JAK inhibitors in the management of moderate to severe Hidradenitis Suppurativa treatment: a scoping review

This scoping review aims to characterize the use of biologics and Janus Kinase inhibitors (JAKi) in the treatment of Hidradenitis Suppurativa (HS), which is a chronic inflammatory condition. A comprehensive literature search was conducted in PubMed/NCBI, Embase, Web of Science databases, and the Clinicaltrials.gov register. The search included interventional trials assessing the use of biologics or JAKi in HS, with no geographic or time restrictions. Secukinumab and adalimumab were identified as the only two drugs approved by the FDA for treating moderate to severe HS in adults. Several other drug classes showed promising results based on clinical studies reviewed. IL-12/23 inhibitor ustekinumab demonstrated improvements in disease severity scores and HiSCR rates in small trials. IL-17 inhibitors such as brodalumab, bimekizumab, and CJM112 showed preliminary positive responses in early-phase clinical studies and case reports. While evidence was mixed, some TNF-α inhibitors such as infliximab provided benefits according to a randomized controlled trial, though etanercept trials yielded non-significant or inconsistent findings. Larger, well-designed studies are required to further establish their efficacy and safety, but biologics and JAKis show potential as alternative treatment options for moderate to severe HS. The findings of this review contribute to the growing interest among patients and to enhancing the understanding of physician's regarding potential alternative therapeutic options for HS and provide a basis for further research in this field.

Biologics for Hidradenitis suppurativa: evolution of the treatment paradigm

INTRODUCTION

Hidradenitis suppurativa (HS) is an autoinflammatory skin disease with a high unmet need for effective medical management. Clinically, it is characterized by inflammatory nodules that may progress into abscesses, draining tunnels and extensive scarring, mainly affecting apocrine gland-bearing areas.

AREAS COVERED

Treatment options include topical and systemic medications and a variety of surgical procedures. The anti-TNF-α antibody adalimumab and the anti-IL-17 secukinumab are the only two approved biologics for HS, showing moderate efficacy. HS research is a rapidly growing field, with a wide range of agents leveraging distinct mechanisms of action currently under development. Drugs targeting the IL-17 and Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways are the most advanced in both ongoing and completed Phase 3 studies, promising deeper levels of response. Use of other, off-label biologics is also discussed.

EXPERT OPINION

A therapeutic algorithm is proposed based on comorbidities and existing evidence. Patient-tailored combinations between biologics and other biologics or small molecules will hopefully allow clinicians to target most events in HS pathophysiology in a complementary way while obtaining a meaningful effect on their devastating manifestations.

Rethinking Hidradenitis Suppurativa Management: Insights into Bacterial Interactions and Treatment Evolution

Hidradenitis suppurativa (HS), or acne inversa, is a chronic inflammatory dermatological condition characterized by painful and recurrent nodules and purulent abscesses. HS can have a devastating impact on the quality of life of patients. This condition is commonly localized to the axilla, groin, perineal, and inframammary regions, and can develop fistulas and sinus tracts over time. Its pathogenesis remains elusive and is best characterized at the moment as multi-factorial. Additionally, questions remain about the role of cutaneous dysbiosis as a primary HS trigger or as a secondary perturbation due to HS inflammation. This article features works in relation to HS and its interplay with bacterial microflora. We address current treatment approaches and their impact on HS-related bacteria, as well as areas of therapeutic innovation. In the future, disease-modifying or remittive therapy will likely combine an advanced/targeted anti-inflammatory approach with one that effectively modulates cutaneous and deep tissue dysbiosis.

Efficacy and safety of the oral Janus kinase 1 inhibitor povorcitinib (INCB054707) in patients with hidradenitis suppurativa in a phase 2, randomized, double-blind, dose-ranging, placebo-controlled study

BACKGROUND

Janus kinase 1 inhibition may alleviate hidradenitis suppurativa (HS)-associated inflammation and improve symptoms.

OBJECTIVE

To assess efficacy and safety of povorcitinib (selective oral Janus kinase 1 inhibitor) in HS.

METHODS

This placebo-controlled phase 2 study randomized patients with HS 1:1:1:1 to receive povorcitinib 15, 45, or 75 mg or placebo for 16 weeks. Primary and key secondary end points were mean change from baseline in abscess and inflammatory nodule count and percentage of patients achieving HS Clinical Response at week 16.

RESULTS

Of 209 patients randomized (15 mg, n = 52; 45 mg, n = 52; 75 mg, n = 53; placebo, n = 52), 83.3% completed the 16-week treatment. At week 16, povorcitinib significantly reduced abscess and inflammatory nodule count from baseline (least squares mean [SE] change: 15 mg, -5.2 [0.9], P = .0277; 45 mg, -6.9 [0.9], P = .0006; 75 mg, -6.3 [0.9], P = .0021) versus placebo (-2.5 [0.9]). More povorcitinib-treated patients achieved HS Clinical Response at week 16 (15 mg, 48.1%, P = .0445; 45 mg, 44.2%, P = .0998; 75 mg, 45.3%, P = .0829) versus placebo (28.8%). A total of 60.0% and 65.4% of povorcitinib- and placebo-treated patients had adverse events.

LIMITATIONS

Baseline lesion counts were mildly imbalanced between groups.

CONCLUSION

Povorcitinib demonstrated efficacy in HS, with no evidence of increased incidence of adverse events among doses.

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.)

Risk of infection in patients with hidradenitis suppurativa on biologics or other immunomodulators: a systematic review and meta-analysis

Hidradenitis suppurativa (HS) is a painful skin condition that significantly affects patients' quality of life. Biologic agents, including anti-TNF agents and IL-17 inhibitors, have shown promise as treatment options for HS. However, there is concern about the increased risk of infections associated with these therapies. We conducted a systematic review and meta-analysis following PRISMA and MOOSE guidelines. We searched PubMed and Embase until February 1, 2023. The primary outcome of interest was the incidence of any infectious complications. Secondary outcomes included serious and opportunistic infections in HS patients treated with biologics or other immunomodulators. Twenty-four studies met our inclusion criteria, comprising 1,696 patients. The pooled incidence rate for any infection was 24.2%, primarily consisting of mild respiratory and skin infections. Subgroup analysis based on the mechanism of action (MOA) showed a pooled incidence of 7.77% for anti-IL1, 14.24% for anti-PDE4, and 21.96% for anti-TNF. Notably, patients receiving anti-IL17 had the highest incidence rate of infection at 33.6%, but the relative risk compared to placebo was not significantly elevated (0.99, 95% CI: 0.86-1.14). Serious infections were rare, with pooled incidences of 0.39% for anti-IL17 and 0.03% for anti-TNF. Opportunistic infections were infrequent, with 10 reported cases, including eight oral candidiasis, one cryptosporidiosis, and one Blastocystis hominis infection. The use of biologic therapies in HS patients does not significantly increase the risk of infectious complications. Additionally, the occurrence of serious or opportunistic infections in HS patients treated with biologics appears to be minimal.

Hidradenitis Suppurativa: An Understanding of Genetic Factors and Treatment

Hidradenitis suppurativa (HS), recognized as a chronic and debilitating skin disease, presents significant challenges in both diagnosis and treatment. This review explores the clinical manifestations, genetic landscape, and molecular mechanisms underlying HS. The disease's association with a predisposing genetic background, obesity, smoking, and skin occlusion underscores the complexity of its etiology. Genetic heterogeneity manifests in sporadic, familial, and syndromic forms, with a focus on mutations in the γ-secretase complex genes, particularly NCSTN. The dysregulation of immune mediators, including TNF-α, IL-17, IL-1β, and IL-12/23, plays a crucial role in the chronic inflammatory nature of HS. Recent advancements in genetic research have identified potential therapeutic targets, leading to the development of anti-TNF-α, anti-IL-17, anti-IL-1α, and anti-IL-12/23 therapies and JAK inhibitors. These interventions offer promise in alleviating symptoms and improving the quality of life for HS patients.

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.

A systematic review of Janus kinase inhibitors and spleen tyrosine kinase inhibitors for Hidradenitis suppurativa treatment

BACKGROUNDS AND AIMS

Hidradenitis suppurativa (HS) is a challenging skin disease with an underlying inflammatory process. Substantial progress has been made in our understanding of HS over the last few years, with the advancement of novel treatment approaches. The current systematic review aims to evaluate the safety and efficacy of Janus kinase (JAK) inhibitors and spleen tyrosine kinase (Syk) inhibitors in treating HS.

METHOD

A thorough systematic search was performed on PubMed/Medline, Web of Science, and Ovid Embase databases up to September 23th, 2023. Clinical studies published in English were included.

RESULTS

Our search yielded ten articles with a total of 165 patients treated with four types of JAK inhibitors (upadacitinib, povorcitinib, tofacitinib, and baricitinib) and one Syk inhibitor (fostamatinib). Upadacitinib, povorcitinib, and tofacitinib improved clinical outcomes, with a significant reduction in hidradenitis suppurativa clinical response (HiSCR) and abscess and inflammatory nodule count (AN count) during the treatment period. Also, these drugs are well tolerated in most HS patients with minimal adverse events (AEs). Moreover, baricitinib depicted an amelioration in signs and symptoms of HS in one case report. Also, fostamatinib exhibited favorable tolerability throughout a 12-week in moderate-to-severe HS patients. The remarkable clinical improvement, as assessed through HiSCR and hidradenitis suppurativa severity (IHS4), corresponded closely with serological indicators of inflammation following fostamatinib administration was achieved.

CONCLUSION

JAK and Syk inhibitors are potentially efficacious in managing moderate-to-severe HS since the proinflammatory cytokines are mediated by JAK and Syk signaling pathways. However, further research with a more rigorous examination is mandatory to evaluate such medication's long-term safety and efficacy.

Secukinumab in Hidradenitis Suppurativa Patients Who Failed Adalimumab: A 52-Week Real-Life Study

Background

The treatment of hidradenitis suppurativa (HS) has always been a real challenge for dermatologists; to date, adalimumab the only biologic drug approved for HS is adalimumab, an anti-tumor necrosis factor (TNF)-α drug, the approval of this drug dates to 2015, data provided by real life show an effectiveness rate of about 60% percent. Recently (31 October 2023) FDA approves secukinumab for moderate-severe HS. The treatment and management of HS is very challenging as available treatments are very limited and show very variable outcomes.

Methods

We conducted a prospective monocentric study designed to evaluate the efficacy and safety of secukinumab treatment in HS patients in a real-life setting.

Results

The initial cohort of patients recruited included 21 HS patients including 12 females and 9 males. About 57.1% of patients achieved the primary endpoint and recorded significant decrease in all the severity assessment scales (IHS4, DLQI and VAS pain scale) at week 16 and 52, when HiSCR reached 71.4%.

Conclusion

The results of our study highlight that treatment with secukinumab in patients with severe HS who failed adalimumab may be a safe and effective therapeutic weapon.

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.

Improvement of Recalcitrant Dissecting Cellulitis of the Scalp After a Trial of Upadacitinib

Dissecting cellulitis of the scalp (DCS) is a rare condition characterized by painful inflammatory nodules and abscesses on the scalp, often leading to sinus tracts and scarring alopecia. We present a case of DCS in a 26-year-old male who experienced significant clinical improvement following a short course of upadacitinib, a Janus kinase (JAK) inhibitor. The patient received multiple standard treatments such as topical antimicrobials, oral antibiotics, corticosteroids, and intralesional triamcinolone injections, with limited success. However, following the initiation of upadacitinib, the patient reported reduced pain, pustular draining, and bleeding, with significantly improved quality of life. To our knowledge, there is currently a paucity of literature documenting the use of JAK inhibitors for DCS. This case aims to highlight the potential of JAK inhibitors as a therapy for refractory DCS, a condition with limited treatment options.

Synthesis and clinical application of small-molecule inhibitors of Janus kinase

Janus kinase (JAK) plays a crucial role in intracellular signaling pathways, particularly in cytokine-mediated signal transduction, making them attractive therapeutic targets for a wide range of diseases, including autoimmune disorders, myeloproliferative neoplasms, and inflammatory conditions. The review provides a comprehensive overview of the development and therapeutic potential of small-molecule inhibitors targeting JAK family of proteins in various clinical trials. It also discusses the mechanisms of action, specificity, and selectivity of these inhibitors, shedding light on the challenges associated with achieving target selectivity while minimizing off-target effects. Moreover, the review offers insights into the clinical applications of JAK inhibitors, summarizing the ongoing clinical trials and the Food and Drug Administration (FDA)-approved JAK inhibitors currently available for various diseases. Overall, this review provides a thorough examination of the synthesis and clinical use of typical small-molecule JAK inhibitors in different clinical stages and offers a bright future for the development of novel small-molecule JAK inhibitors.

NK and NKT cells in the pathogenesis of Hidradenitis suppurativa: Novel therapeutic strategy through targeting of CD2

Hidradenitis suppurativa (HS) is a chronic debilitating inflammatory skin disease with poorly understood pathogenesis. Single-cell RNAseq analysis of HS lesional and healthy individual skins revealed that NKT and NK cell populations were greatly expanded in HS, and they expressed elevated CD2, an activation receptor. Immunohistochemistry analyses confirmed significantly expanded numbers of CD2+ cells distributed throughout HS lesional tissue, and many co-expressed the NK marker, CD56. While CD4+ T cells were expanded in HS, CD8 T cells were rare. CD20+ B cells in HS were localized within tertiary follicle like structures. Immunofluorescence microscopy showed that NK cells (CD2 + CD56 dim ) expressing perforin, granzymes A and B were enriched within the hyperplastic follicular epidermis and tunnels of HS and juxtaposed with apoptotic cells. In contrast, NKT cells (CD2 + CD3 + CD56 bright ) primarily expressed granzyme A and were associated with α-SMA expressing fibroblasts within the fibrotic regions of the hypodermis. Keratinocytes and fibroblasts expressed high levels of CD58 (CD2 ligand) and they interacted with CD2 expressing NKT and NK cells. The NKT/NK maturation and activating cytokines, IL-12, IL-15 and IL-18, were significantly elevated in HS. Inhibition of cognate CD2-CD58 interaction with blocking anti-CD2 mAb in HS skin organotypic cultures resulted in a profound reduction of the inflammatory gene signature and secretion of inflammatory cytokines and chemokines in the culture supernate. In summary, we show that a cellular network of heterogenous NKT and NK cell populations drives inflammation, tunnel formation and fibrosis in the pathogenesis of HS. Furthermore, CD2 blockade is a viable immunotherapeutic approach for the management of HS.

JAK-STAT pathway inhibitors in dermatology

The JAK-STAT signaling pathway mediates important cellular processes such as immune response, carcinogenesis, cell differentiation, division and death. Therefore, drugs that interfere with different JAK-STAT signaling patterns have potential indications for various medical conditions. The main dermatological targets of JAK-STAT pathway inhibitors are inflammatory or autoimmune diseases such as psoriasis, vitiligo, atopic dermatitis and alopecia areata; however, several dermatoses are under investigation to expand this list of indications. As JAK-STAT pathway inhibitors should gradually occupy a relevant space in dermatological prescriptions, this review presents the main available drugs, their immunological effects, and their pharmacological characteristics, related to clinical efficacy and safety, aiming to validate the best dermatological practice.

Inborn Errors of Immunity in Hidradenitis Suppurativa Pathogenesis and Disease Burden

Hidradenitis suppurativa (HS), also known as Verneuil's disease and acne inversa, is a prevalent, debilitating, and understudied inflammatory skin disease. It is marked by repeated bouts of pathological inflammation causing pain, hyperplasia, aberrant healing, and fibrosis. HS is difficult to manage and has many unmet medical needs. There is clinical and pharmacological evidence for extensive etiological heterogeneity with HS, suggesting that this clinical diagnosis is capturing a spectrum of disease entities. Human genetic studies provide robust insight into disease pathogenesis. They also can be used to resolve etiological heterogeneity and to identify drug targets. However, HS has not been extensively investigated with well-powered genetic studies. Here, we review what is known about its genetic architecture. We identify overlap in molecular, cellular, and clinical features between HS and inborn errors of immunity (IEI). This evidence indicates that HS may be an underrecognized component of IEI and suggests that undiagnosed IEI are present in HS cohorts. Inborn errors of immunity represent a salient opportunity for rapidly resolving the immunological landscape of HS pathogenesis, for prioritizing drug repurposing studies, and for improving the clinical management of HS.

The Importance of the Pyrazole Scaffold in the Design of Protein Kinases Inhibitors as Targeted Anticancer Therapies

The altered activation or overexpression of protein kinases (PKs) is a major subject of research in oncology and their inhibition using small molecules, protein kinases inhibitors (PKI) is the best available option for the cure of cancer. The pyrazole ring is extensively employed in the field of medicinal chemistry and drug development strategies, playing a vital role as a fundamental framework in the structure of various PKIs. This scaffold holds major importance and is considered a privileged structure based on its synthetic accessibility, drug-like properties, and its versatile bioisosteric replacement function. It has proven to play a key role in many PKI, such as the inhibitors of Akt, Aurora kinases, MAPK, B-raf, JAK, Bcr-Abl, c-Met, PDGFR, FGFRT, and RET. Of the 74 small molecule PKI approved by the US FDA, 8 contain a pyrazole ring: Avapritinib, Asciminib, Crizotinib, Encorafenib, Erdafitinib, Pralsetinib, Pirtobrutinib, and Ruxolitinib. The focus of this review is on the importance of the unfused pyrazole ring within the clinically tested PKI and on the additional required elements of their chemical structures. Related important pyrazole fused scaffolds like indazole, pyrrolo[1,2-b]pyrazole, pyrazolo[4,3-b]pyridine, pyrazolo[1,5-a]pyrimidine, or pyrazolo[3,4-d]pyrimidine are beyond the subject of this work.

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.

Efficacy and safety of Janus kinase inhibitors in axial spondyloarthritis

Skin manifestations are common in axial spondyloarthritis (axSpA) and may precede axial involvement. Multidisciplinary management of patients with spondyloarthritis (SpA) is essential. Combined dermatology-rheumatology clinics are established for early recognition of the disease, comorbidities and a comprehensive treatment approach. Treatment options for axSpA are limited because conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and glucocorticoids are ineffective for axial symptoms. Janus kinase inhibitors (JAKi) are targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) that decrease transduction signalling to the nucleus, resulting in a reduced inflammatory response. Currently, tofacitinib and upadacitinib are approved for treating axSpA in patients with inadequate response to TNF inhibitors (TNFi). Upadacitinib has shown efficacy in non-radiographic axSpA (nr-axSpA), suggesting that JAKi are efficacious across the spectrum of axSpA. The availability of JAKi has opened more options for patients with active axSpA based on the efficacy data and the ease of administration.

The Current Clinical Trial Landscape for Hidradenitis Suppurativa: A Narrative Review

Hidradenitis suppurativa (HS) is a skin disease resulting from chronic, recurrent inflammation around hair follicles, characterized by proinflammatory cytokines such as IL-1, IL-17, IL-23, and TNF-α. While adalimumab, a TNF-α targeting human IgG monoclonal antibody, is the only approved treatment for HS, there are many other therapies being investigated now targeting other key players in inflammatory pathways such as the cytokines listed above, C5a in the complement pathway, and Janus kinase (JAK). This review discusses current clinical trials for biologics and small molecules, procedures, and wound dressings undergoing study in hidradenitis suppurativa.

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.

Modulation of Disease-Associated Pathways in Hidradenitis Suppurativa by the Janus Kinase 1 Inhibitor Povorcitinib: Transcriptomic and Proteomic Analyses of Two Phase 2 Studies

Janus kinase (JAK)/signal transducer and activator of transcription signaling (STAT) has been implicated in the pathophysiology of hidradenitis suppurativa (HS). This study evaluated treatment-related transcriptomic and proteomic changes in patients with moderate-to-severe HS treated with the investigational oral JAK1-selective inhibitor povorcitinib (INCB054707) in two phase 2 trials. Lesional skin punch biopsies (baseline and Week 8) were taken from active HS lesions of patients receiving povorcitinib (15 or 30 mg) once daily (QD) or a placebo. RNA-seq and gene set enrichment analyses were used to evaluate the effects of povorcitinib on differential gene expression among previously reported gene signatures from HS and wounded skin. The number of differentially expressed genes was the greatest in the 30 mg povorcitinib QD dose group, consistent with the published efficacy results. Notably, the genes impacted reflected JAK/STAT signaling transcripts downstream of TNF-α signaling, or those regulated by TGF-β. Proteomic analyses were conducted on blood samples obtained at baseline and Weeks 4 and 8 from patients receiving povorcitinib (15, 30, 60, or 90 mg) QD or placebo. Povorcitinib was associated with transcriptomic downregulation of multiple HS and inflammatory signaling markers as well as the reversal of gene expression previously associated with HS lesional and wounded skin. Povorcitinib also demonstrated dose-dependent modulation of several proteins implicated in HS pathophysiology, with changes observed by Week 4. The reversal of HS lesional gene signatures and rapid, dose-dependent protein regulation highlight the potential of JAK1 inhibition to modulate underlying disease pathology in HS.

Perifolliculitis capitis abscedens et suffodiens treatment with tumor necrosis factor inhibitors and baricitinib: A case report and literature review

Rationale

Perifolliculitis capitis abscedens et suffodiens (PCAS), also known as dissecting cellulitis of the scalp (DCS), is a part of the “follicular occlusion tetrad” that also includes acne conglobate (AC), hidradenitis suppurativa (HS), and pilonidal sinus, which share the same pathogenic mechanism, such as follicular occlusions, follicular ruptures, and follicular infections.

Patient concerns

A 15-year-old boy had multiple rashes on the scalp accompanied by pain.

Diagnosis

The patient was diagnosed with PCAS or DCS based on the clinical manifestations and laboratory examinations.

Interventions

The patient was initially administered adalimumab 40 mg biweekly and oral isotretinoin 30 mg daily for 5 months. Because the initial results were insufficient, the interval between adalimumab injections was extended to 4 weeks, and isotretinoin was changed to baricitinib 4 mg daily for 2 months. When the condition became more stable, adalimumab 40 mg and baricitinib 4 mg were administered every 20 and 3 days, respectively, for two more months until now.

Outcomes

After 9 months of treatment and follow-up, the original skin lesions of the patient were almost cured, and most inflammatory alopecia patches disappeared.

Conclusion

Our literature review did not find any previous reports on treating PCAS with TNF-α inhibitors and baricitinib. Accordingly, we presented the first successful treatment of PCAS with this regimen.

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.

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.

Initial validation of the Hidradenitis Suppurativa Quality of Life tool in a clinical trial setting

We tested a new patient-reported outcome tool, the Hidradenitis Suppurativa Quality of Life (HiSQoL) questionnaire, which is designed to measure quality of life (QoL) in adults with hidradenitis suppurativa (HS). The HiSQoL demonstrated validity and reliability, and may be a useful tool for measuring QoL, especially in clinical trials testing new drugs in HS.

Current Medical and Surgical Treatment of Hidradenitis Suppurativa-A Comprehensive Review

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease presenting with recurrent inflammatory lesions in intertriginous body regions. HS has a pronounced impact on patients' quality of life and is associated with a variety of comorbidities. Treatment of HS is often complex, requiring an individual approach with medical and surgical treatments available. However, especially in moderate-to-severe HS, there is an urgent need for new treatment approaches. In recent years, increased research has led to the identification of new potential therapeutic targets. This review aims to give a comprehensive and practical overview of current treatment options for HS. Furthermore, the clinically most advanced novel treatment approaches will be discussed.

Immunomodulatory Drugs in the Treatment of Hidradenitis Suppurativa-Possibilities and Limitations

Hidradenitis suppurativa, also known as acne inversa, is a chronic, progressive, debilitating, recurrent inflammatory skin disease characterized by the occurrence of very severe, persistent, painful nodules, abscesses, and fistulas, most commonly found in the skin folds of the axilla, groin, gluteal, and perianal areas. Treatment is rather difficult and typically requires the use of multiple modalities. Regardless of the presence of several therapeutic options, treatment often turns out to be ineffective or poorly selected concerning the clinical picture of the disease. Thus, the search for new biologics and other target treatments of hidradenitis suppurativa is ongoing. The safety and efficacy of adalimumab, still the only U.S. Food and Drug Administration approved biologic in the hidradenitis suppurativa treatment, paved the way for new drugs to be compared with it. Several more drugs with new immunological targets are currently under investigation for the treatment of acne inversa. The aim of the article was to present the current and future targets of acne inversa treatment, simultaneously providing insights into the molecular pathomechanisms of the disease.