Improved clinical effectiveness of adalimumab when initiated with clindamycin and rifampicin in hidradenitis suppurativa.

BACKGROUND: Adalimumab monotherapy for hidradenitis suppurativa (HS) is often insufficient with a maximum clinical efficacy of 60% in Hidradenitis Suppurativa Clinical Response (HiSCR) and limited effect on draining tunnels. Data suggest that adalimumab therapy could be improved by concomitant antibiotics. OBJECTIVE: To compare the clinical effectiveness of adalimumab with clindamycin and rifampicin versus adalimumab monotherapy after 12 weeks. METHODS: This retrospective study included patients who started adalimumab with additional clindamycin and rifampicin and patients treated with adalimumab monotherapy, matched on sex and refined Hurley score. The primary outcome measure was the difference in change in the International Hidradenitis Suppurativa Severity Score System (IHS4) at 12 weeks. RESULTS: In total, 62 patients were included in the combination therapy group (n = 31) and adalimumab monotherapy group (n = 31), showing comparable IHS4 scores; 32.5 versus 29, p = 0.87 at baseline respectively. The combination therapy demonstrated greater clinical effectiveness expressed in median IHS4 improvement (-20 vs. -9, p < 0.001), IHS4-55 (74% vs. 36%, p = 0.002), median draining tunnel reduction (-4 vs. -2, p < 0.001) and pain response (47% vs. 27%, p = 0.02). CONCLUSION: Adalimumab initiated with clindamycin and rifampicin shows greater clinical effectiveness than adalimumab monotherapy. An important difference in effect was observed in the decrease of draining tunnels, addressing a serious limitation of adalimumab monotherapy.

Complement activation in Hidradenitis suppurativa: Covert low-grade inflammation or innocent bystander?

Hidradenitis suppurativa (HS) is a chronic auto-inflammatory skin disease with a complex and multifactorial pathogenesis involving both the innate and adaptive immune system. Despite limited evidence for local complement activation, conflicting results have been published on the role of systemic complement activation in HS. It was hypothesized that complement was consumed in highly inflamed HS skin, trapping complement from the circulation. Therefore, the aim of this study was to evaluate this local complement deposition in HS skin lesions using routine and commonly used complement antibodies.Direct immunofluorescence for C1q, C3c, C4d, C5b-9, and properdin was performed on frozen tissue sections of 19 HS patients and 6 controls. C5a receptor 1 (C5aR1) was visualized using immunohistochemistry. Overall, we found no significant local complement deposition in HS patients versus controls regarding C1q, C3c, C4d, C5b-9, or properdin on either vessels or immune cells. C5aR1 expression was exclusively found on immune cells, predominantly neutrophilic granulocytes, but not significantly different relatively to the total infiltrate in HS lesions compared with controls. In conclusion, despite not being able to confirm local complement depositions of C1q, C3c, C4d, or properdin using highly sensitive and widely accepted techniques, the increased presence of C5aR1 positive immune cells in HS suggests the importance of complement in the pathogenesis of HS and supports emerging therapies targeting this pathway.

Primary alterations during the development of hidradenitis suppurativa.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory disease of the apocrine gland-rich (AGR) skin region. The initial steps of disease development are not fully understood, despite intense investigations into immune alterations in lesional HS skin. OBJECTIVES: We aimed to systematically investigate the inflammatory molecules involved in three stages of HS pathogenesis, including healthy AGR, non-lesional HS and lesional HS skin, with the parallel application of multiple mRNA and protein-based methods. METHODS: Immune cell counts (T cells, dendritic cells, macrophages), Th1/Th17-related molecules (IL-12B, TBX21, IFNG, TNFA, IL-17, IL10, IL-23A, TGFB1, RORC, CCL20), keratinocyte-related sensors (TLR2,4), mediators (S100A7, S100A8, S100A9, DEFB4B, LCN2, CAMP, CCL2) and pro-inflammatory molecules (IL1B, IL6, TNFA, IL-23A) were investigated in the three groups by RNASeq, RT-qPCR, immunohistochemistry and immunofluorescence. RESULTS: Epidermal changes were already detectable in non-lesional HS skin; the epidermal occurrence of antimicrobial peptides (AMPs), IL-1ß, TNF-α and IL-23 was highly upregulated compared with healthy AGR skin. In lesional HS epidermis, TNF-α and IL-1ß expression remained at high levels while AMPs and IL-23 increased even more compared with non-lesional skin. In the dermis of non-lesional HS skin, signs of inflammation were barely detectable (vs. AGR), while in the lesional dermis, the number of inflammatory cells and Th1/Th17-related mediators were significantly elevated. CONCLUSIONS: Our findings that non-lesional HS epidermal keratinocytes produce not only AMPs and IL-1ß but also high levels of TNF-α and IL-23 confirm the driver role of keratinocytes in HS pathogenesis and highlight the possible role of keratinocytes in the transformation of non-inflammatory Th17 cells (of healthy AGR skin) into inflammatory cells (of HS) via the production of these mediators. The fact that epidermal TNF-α and IL-23 appear also in non-lesional HS seems to prove these cytokines as excellent therapeutic targets.

Quantitative intracellular oxygen availability before and after 5-aminolevulinic acid skin photodynamic therapy.

BACKGROUND: During photodynamic therapy (PDT) oxygen is transformed into reactive oxygen species (ROS) to induce cellular apoptosis in (pre)malignant cells. Real time oxygen availability measurement is clinically available with the Cellular Oxygen Metabolism (COMET) monitor. METHODS: Primary objective is to show that mitochondrial oxygen availability (mitoPO2) measurement is possible during clinical ALA-PDT. The secondary aim was to determine the pain sensation, because it is the most commonly reported side effect of PDT. Before and after the two fraction PDT treatment, with a 2-hour dark period, mitoPO2 was measured and reported pain was documented with a visual analog scale (VAS) 0-100. RESULTS: Nine patients were included. Before the first PDT session the median signal quality was [IQR] 55.0% [34.2-68.0], which decreased after session one to 0% [0.0-10.0]. MitoPO2 was 40.0 [17.7-53.8] mmHg and increased afterwards to 61.8 [38.2-64.8] mmHg. This likely the result of the delay time between the illumination stop and the mitoPO2 measurements in a vasodilated, visibly red lesion. Before session two signal quality was 10.4% [0-20.15], 40% lower than at the start. In 5 patients the signal quality after session 2 was too low because of photobleaching and insufficient regeneration of PpIX, median 0% [0-10]. Subjects reported low median VAS scores, all below 3, directly after the mitoPO2 measurements. CONCLUSION: With COMET we were able to reliably measure mitochondrial oxygen concentrations during photodynamic therapy. Signal quality drastically decreases after a PDT session because of PpIX deterioration during the illumination phase.

Adalimumab and infliximab survival in patients with hidradenitis suppurativa: a daily practice cohort study.

BACKGROUND: Biologics are often required for the treatment of hidradenitis suppurativa (HS). However, data on the drug survival of biologics in daily practice are currently lacking. OBJECTIVES: To assess the drug survival of antitumour necrosis factor biologics in a daily practice cohort of patients with HS and to identify predictors for drug survival. METHODS: A retrospective multicentre study was performed in two academic dermatology centres in the Netherlands. Adult patients with HS using biologics between 2008 and 2020 were included. Drug survival was analysed with Kaplan-Meier survival curves and predictors of survival with univariate Cox regression analysis. RESULTS: The overall drug survival of adalimumab (n = 104) at 12 and 24 months was 56·3% and 30·5%, respectively, which was predominantly determined by infectiveness. Older age (P = 0·02) and longer disease duration (P < 0·01) were associated with longer survival time. For infliximab (n = 44), overall drug survival was 58·3% and 48·6% at 12 and 24 months, respectively, and was predominantly determined by infectiveness and side-effects. Surgery during treatment was associated with a longer survival time (P = 0·01). CONCLUSIONS: Survival rates were comparable for adalimumab and infliximab at 12 months, and were mainly determined by ineffectiveness. Age, disease duration (adalimumab) and surgery (infliximab) are predictors for longer survival.

A novel nicastrin mutation in a three-generation Dutch family with hidradenitis suppurativa: a search for functional significance.

BACKGROUND: Mutations in the γ-secretase enzyme subunits have been described in multiple kindreds with familial hidradenitis suppurativa (HS). OBJECTIVE: In this study, we report a novel nicastrin (NCSTN) mutation causing HS in a Dutch family. We sought to explore the immunobiological function of NCSTN mutations using data of the Immunological Genome Project. METHODS: Blood samples of three affected and two unaffected family members were collected. Whole-genome sequencing was performed using genomic DNA isolated from peripheral blood leucocytes. Sanger sequencing was done to confirm the causative NCSTN variant and the familial segregation. The microarray data set of the Immunological Genome Project was used for thorough dissection of the expression and function of wildtype NCSTN in the immune system. RESULTS: In a family consisting of 23 members, we found an autosomal dominant inheritance pattern of HS and detected a novel splice site mutation (c.1912_1915delCAGT) in the NCSTN gene resulting in a frameshift and subsequent premature stop. All affected individuals had HS lesions on non-flexural and atypical locations. Wildtype NCSTN appears to be upregulated in myeloid cells like monocytes and macrophages, and in mesenchymal cells such as fibroblastic reticular cells and fibroblasts. In addition, within the 25 highest co-expressed genes with NCSTN we identified CAPNS1, ARNT and PPARD. CONCLUSION: This study reports the identification a novel NCSTN gene splice site mutation which causes familial HS. The associated immunobiological functions of NCSTN and its co-expressed genes ARNT and PPARD link genetics to the most common environmental and metabolic HS risk factors which are smoking and obesity.

Current and future treatment of hidradenitis suppurativa.

This scholarly review on the current and future treatment of hidradenitis suppurativa (HS) focuses on medical and surgical treatment options, while novel pipeline drugs are also discussed. Treatment goals are to limit the incidence and duration of flares, reducing inflammation and suppuration, achieving local cure after surgery and, most importantly, to improve the quality of life of patients with HS. The type of medication and/or surgery should be chosen based on the stage of the disease and the degree of inflammation. However, the lack of a simple scoring system and the lack of clear surgical outcome definitions hamper the interpretation of treatment efficacy and the comparison between different treatment strategies. The therapeutic pipeline for HS is gradually expanding, and will probably lead to a broader panel of more effective therapeutic options.

Adalimumab medium-term dosing strategy in moderate-to-severe hidradenitis suppurativa: integrated results from the phase III randomized placebo-controlled PIONEER trials.

BACKGROUND: Weekly adalimumab (Humira® ) is approved for the treatment of hidradenitis suppurativa (HS) based on the 12-week placebo-controlled periods of the two phase III PIONEER trials. OBJECTIVES: Using PIONEER integrated trial results, we aimed to evaluate the optimal medium-term adalimumab maintenance dosing strategy for moderate-to-severe HS. METHODS: Each trial had two double-blind periods; 12-week Period A and 24-week Period B. Patients randomized to adalimumab 40 mg every week (ADAew) (Period A), were rerandomized in Period B to ADAew (ADAew/ew), ADA every other week (ADAew/eow), or placebo (ADAew/pbo). Placebo-randomized patients were reassigned in Period B to ADAew (PIONEER I) or placebo (PIONEER II). The primary outcome was HS Clinical Response (HiSCR). Patients who lost response during Period B were discontinued from the study and offered an option to enter the open-label extension (OLE) to receive ADAew. Results are reported across the two study periods, and data were combined from the two study periods and the OLE. RESULTS: For week-12 HiSCR achievers, the HiSCR week-36 rate was 48·1% (ADAew/ew) vs. 46·2% (ADAew/eow) and 32·1% (ADAew/pbo). Combining (post hoc) these patients with week-12 partial responders further differentiated outcomes in Period B (ADAew/ew 55·7% vs. ADAew/eow 40·0% and ADAew/pbo 30·1%). Period-B adverse-event rates were ADAew/ew 59·6% vs. ADAew/eow 57·4% and ADAew/pbo 65·0%. One patient (ADAew/ew) reported a serious infection. CONCLUSIONS: Weekly adalimumab treatment, effective throughout 36 weeks, was the optimal maintenance medium-term dosing regimen for this population. At least partial response after 12 weeks with continued weekly dosing had better outcomes than dose reduction or interruption. Patients who do not show at least a partial response to weekly adalimumab by week 12 are unlikely to benefit from continued therapy. No new safety risks were identified. What's already known about this topic? Hidradenitis suppurativa (HS) is a chronic inflammatory disease, commonly misinterpreted as an infection and treated with long-term antibiotic regimens or surgical incisions. Based on the chronicity of HS and the lack of evidence for efficacious and safe long-term HS treatments, it is important to evaluate medium- to long-term therapies for HS. Weekly adalimumab (Humira® ) is approved for the treatment of moderate-to-severe HS based on the two phase III PIONEER trials. What does this study add? This study pooled data from the two PIONEER trials, providing a more robust assessment of outcomes. After at least partial treatment success with weekly adalimumab short-term therapy (12 weeks), continuing weekly dosing during the subsequent 24 weeks had better outcomes than dose reduction or treatment interruption. Patients who do not show at least a partial response to weekly adalimumab by week 12 are unlikely to benefit from continued therapy.

The anti-inflammatory potency of biologics targeting tumour necrosis factor-α, interleukin (IL)-17A, IL-12/23 and CD20 in hidradenitis suppurativa: an ex vivo study.

BACKGROUND: Biologics targeting inflammatory mediators can achieve clinical improvements in hidradenitis suppurativa (HS). However, their clinical efficacy shows great interpatient variability in daily practice. OBJECTIVES: To investigate the anti-inflammatory potency of a selection of currently available biologics and prednisolone for the treatment of HS in an ex vivo skin culture system using lesional HS biopsies. METHODS: Lesional skin samples from 10 patients with HS and skin samples from five healthy controls were cultured ex vivo and exposed to prednisolone or biologics targeting tumour necrosis factor (TNF)-α, interleukin (IL)-17A, IL-12/23p40 or CD20 (adalimumab, infliximab, secukinumab, ustekinumab and rituximab, respectively). Real-time quantitative polymerase chain reaction and cytokine bead arrays were used to measure the inhibitory effect of the biologics on cytokines and antimicrobial peptides (AMPs). RESULTS: The relative mRNA expression of all tested cytokines and AMPs was significantly downregulated by all anti-inflammatory agents (P < 0·001). The protein production of the proinflammatory cytokines TNF-α, interferon γ, IL-1ß, IL-6 and IL-17A was significantly inhibited by adalimumab, infliximab, ustekinumab, prednisolone (all P < 0·001) and rituximab (P = 0·0071), but not by secukinumab (P = 0·0663). On both mRNA and protein levels, adalimumab, infliximab and prednisolone reduced the levels of a broader mix of individual cytokines than secukinumab, ustekinumab and rituximab. Moreover, a significant inhibitory effect on mRNA expression levels of inflammatory markers in healthy control skin was observed only for TNF-α inhibitors (P < 0·001) and prednisolone (P = 0·0015). CONCLUSIONS: This ex vivo study suggests that TNF-α inhibitors and prednisolone are the most powerful inhibitors of proinflammatory cytokines and AMPs in HS lesional skin, which concurs with our clinical experience in patients with HS.

Hidradenitis suppurativa/acne inversa: a practical framework for treatment optimization - systematic review and recommendations from the HS ALLIANCE working group.

Hidradenitis suppurativa (HS)/acne inversa is a debilitating chronic disease that remains poorly understood and difficult to manage. Clinical practice is variable, and there is a need for international, evidence-based and easily applicable consensus on HS management. We report here the findings of a systematic literature review, which were subsequently used as a basis for the development of international consensus recommendations for the management of patients with HS. A systematic literature review was performed for each of nine clinical questions in HS (defined by an expert steering committee), covering comorbidity assessment, therapy (medical, surgical and combinations) and response to treatment. Included articles underwent data extraction and were graded according to the Oxford Centre for Evidence-based Medicine criteria. Evidence-based recommendations were then drafted, refined and voted upon, using a modified Delphi process. Overall, 5310 articles were screened, 171 articles were analysed, and 65 were used to derive recommendations. These articles included six randomized controlled trials plus cohort studies and case series. The highest level of evidence concerned dosing recommendations for topical clindamycin in mild disease (with systemic tetracyclines for more frequent/widespread lesions) and biologic therapy (especially adalimumab) as second-line agents (following conventional therapy failure). Good-quality evidence was available for the hidradenitis suppurativa clinical response (HiSCR) as a dichotomous outcome measure in inflammatory areas under treatment. Lower-level evidence supported recommendations for topical triclosan and oral zinc in mild-to-moderate HS, systemic clindamycin and rifampicin in moderate HS and intravenous ertapenem in selected patients with more severe disease. Intralesional or systemic steroids may also be considered. Local surgical excision is suggested for mild-to-moderate HS, with wide excision for more extensive disease. Despite a paucity of good-quality data on management decisions in HS, this systematic review has enabled the development of robust and easily applicable clinical recommendations for international physicians based on graded evidence.