Secukinumab efficacy on resolution of enthesitis in psoriatic arthritis: pooled analysis of two phase 3 studies

Targeting cytokines in psoriatic arthritis

Psoriatic arthritis (PsA) is part of the psoriatic disease spectrum and is characterized by a chronic inflammatory process that affects entheses, tendons and joints. Cytokines produced by immune and non-immune cells play a central role in the pathogenesis of PsA by orchestrating key aspects of the inflammatory response. Pro-inflammatory cytokines such as TNF, IL-23 and IL-17 have been shown to regulate the initiation and progression of PsA, ultimately leading to the destruction of the architecture of the local tissues such as soft tissue, cartilage and bone. The important role of cytokines in PsA has been underscored by the clinical success of antibodies that neutralize their function. In addition to biologic agents targeting individual pro-inflammatory cytokines, signaling inhibitors that block multiple cytokines simultaneously such as JAK inhibitors have been approved for PsA therapy. In this review, we will focus on our current understanding of the role of cytokines in the disease process of PsA and discuss potential new treatment options based on modulation of cytokine function.

Enthesitis in patients with psoriatic arthritis treated with secukinumab or adalimumab: a post hoc analysis of the EXCEED study

OBJECTIVES

To evaluate enthesitis treatment response, including time to resolution and data from multiple enthesitis instruments, in patients with PsA treated with secukinumab or adalimumab for 52 weeks.

METHODS

In this post hoc analysis of the EXCEED study, patients receiving secukinumab 300 mg or adalimumab 40 mg per the label were grouped by presence or absence of baseline enthesitis based on the Leeds Enthesitis Index (LEI) and the Spondyloarthritis Research Consortium of Canada Enthesitis Index (SPARCC). Efficacy was assessed according to several enthesitis-related instruments using non-responder imputation for the achievement of enthesitis resolution (LEI/SPARCC = 0), Kaplan-Meier analysis for time to resolution, and as-observed data for other outcomes.

RESULTS

Enthesitis was present at baseline in 498 of 851 patients (58.5%) as assessed by LEI and in 632 of 853 patients (74.1%) as assessed by SPARCC. Patients with baseline enthesitis generally presented with greater disease activity. Similar proportions of patients receiving secukinumab or adalimumab achieved resolution of LEI and SPARCC at weeks 24 (secukinumab: LEI/SPARCC, 49.6%/45.8%; adalimumab: LEI/SPARCC, 43.6%/43.5%) and 52 (secukinumab: LEI/SPARCC, 60.7%/53.2%; adalimumab: LEI/SPARCC, 55.3%/51.4%), with comparable mean time to enthesitis resolution. Improvements were similar for both drugs at individual enthesitis sites. Resolution of enthesitis with secukinumab or adalimumab was associated with improvements in quality of life at week 52.

CONCLUSION

Secukinumab and adalimumab showed similar efficacy, including time to resolution, with respect to resolution of enthesitis. Inhibition of IL-17 with secukinumab reduced clinical enthesitis similarly to TNF-α inhibition.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02745080.

Real-world effectiveness and persistence of secukinumab in the treatment of patients with psoriatic arthritis

Introduction

Psoriatic arthritis (PsA) is a complex and heterogeneous inflammatory disease. Secukinumab, a biologic disease-modifying antirheumatic drug (bDMARD), has extensive clinical evidence of efficacy and safety in the treatment of PsA but data in clinical practice are still limited. This study aims to provide real-world evidence on secukinumab use, effectiveness, and persistence in PsA.

Methods

A retrospective, multicenter study was conducted on patients diagnosed with PsA and treated with secukinumab up to June 2021 at 12 centers in the Valencian Community (Spain). Data on DAS28-CRP, DAPSA, Tender and Swollen Joint Counts (TJC, SJC), enthesitis, dactylitis, skin and nail involvement, pain, patient and physician global assessment (ptGA, phGA) using 100-mm visual analog scale (VAS), and persistence for up to 24 months were collected.

Results

A total of 178 patients were included (49% men; mean [standard deviation, SD] age: 51.4 [10.5] years; 39% obese). Secukinumab was used as a first-, second-, or ≥ third-line bDMARD in 37, 21, and 42% of patients, respectively. The percentage of patients achieving at least low disease activity (DAS28-CRP ≤ 3.2) increased from 25% at baseline to 66% at month 6 (M6) and was maintained (75%) up to M24. Mean (SD) DAS28-CRP baseline values (3.9 [1.2]) decreased to 2.9 (1.1) (p < 0.001) at M6 and remained low through M24 (2.6 [1.1]) (p < 0.001). Secukinumab also improved peripheral arthritis increasing the percentage of patients with TJC = 0 (20% baseline; 57% M24) and SJC = 0 (37% baseline; 80% M24). Treatment reduced the percentage of patients with enthesitis (25% baseline; 6% M24), dactylitis (20% baseline; 4% M24), and skin (70% baseline; 17% M24), and nail (32% baseline; 2% M24) involvement. Additionally, we observed improvements in the mean pain VAS (-26.4 mm M24), ptGA (-26.2 mm M24), and phGA (-24.8 mm M24). Secukinumab showed an overall 24-month persistence rate of 67% (95% confidence interval [CI]: 60-74%). Patients receiving first-line secukinumab showed the highest 24-month persistence rate (83, 95% CI: 73-92; p = 0.024).

Conclusion

Secukinumab showed long-term effectiveness across the six key PsA domains thus reducing disease activity and pain, which are major treatment goals. This was accompanied by high persistence rates, especially in bDMARD naive patients.

Neutrophil function following treatment of psoriatic arthritis patients with secukinumab: altered cytokine signalling but no impairment of host defence

OBJECTIVES

Identifying that dysfunction of the IL-23/17 axis underlies PsA has led to the development of effective targeted therapies such as the IL-17A inhibitor secukinumab. As IL-17A stimulates the secretion of neutrophil chemoattractants, such as CXCL8 (IL-8), we examined the effect of secukinumab on neutrophil function in PsA.

METHODS

Nineteen patients with active PsA were treated with secukinumab. Clinical response [PsA Response Criteria (PsARC) and Psoriasis Area and Severity Index (PASI)] and peripheral blood neutrophil function (apoptosis, receptor expression, phagocytosis/killing, chemotaxis and RNA expression) were measured at 12 week intervals for 48 weeks and compared with age- and sex-matched healthy controls.

RESULTS

At 12 weeks, 12/16 (75%) patients had a PsARC response (100% at 36 weeks) and 10/14 (71%) achieved a 90% PASI response. At baseline, there were no differences in PsA neutrophil reactive oxygen species generation, constitutive or cytokine-delayed apoptosis, chemotaxis or phagocytosis of opsonized Staphylococcus aureus compared with healthy controls. Similarly, there were no differences in these functions from baseline to 12 weeks of therapy. However, surface levels of CD11b/CD18 and CD63 increased and expression of CD16 decreased during therapy. In addition, in a subgroup of early (12 week) responders to secukinumab, RNA sequencing revealed transcriptome changes predicting down-regulation of cytokine signalling and chemotaxis pathways and up-regulation of de novo gene expression pathways, including translation initiation, mRNA catabolism and translation.

CONCLUSION

Complex changes in the properties of circulating neutrophils occur with secukinumab treatment in PsA that may indicate altered responsiveness to changes in both local and systemic levels of pro-inflammatory cytokines. However, host defence processes of neutrophils were unaltered.

Efficacy of tofacitinib on enthesitis in patients with active psoriatic arthritis: analysis of pooled data from two phase 3 studies

BACKGROUND

Tofacitinib is an oral Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA). This post hoc analysis assessed tofacitinib efficacy on enthesitis by baseline location and severity, and impact on disease activity and patient-reported outcomes (PROs), in patients with PsA.

METHODS

Data were pooled from two phase 3 studies (NCT01877668/NCT01882439) in patients with PsA receiving tofacitinib 5 or 10 mg twice daily to month (M)6 or placebo to M3. Endpoints were: change from baseline in Leeds Enthesitis Index (LEI) or Spondyloarthritis Research Consortium of Canada Enthesitis Index (SPARCC); proportions of patients with enthesitis, relapsed enthesitis after resolution, de novo enthesitis, low disease activity (LDA) or remission (minimal disease activity/very low disease activity; Psoriatic Arthritis Disease Activity Score; Disease Activity Index for Psoriatic Arthritis, and Composite Psoriatic Disease Activity in Psoriatic Arthritis); and PROs (Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-F] total and arthritis pain Visual Analog Scale scores). Descriptive statistics were generated by visit and treatment. Change from baseline in PROs was evaluated by multivariate linear regression.

RESULTS

Seven hundred ten patients from two studies were included: 479 had LEI > 0; 545 had SPARCC > 0; and 136 had LEI = 0 and SPARCC = 0 at baseline. At baseline, among patients with LEI > 0 or SPARCC > 0, mean LEI and SPARCC across treatments and enthesitis locations/severities ranged from 1.0-4.4 and 1.3-9.4, respectively. Across several baseline enthesitis locations/severities, changes from baseline in LEI and SPARCC up to M3 were greater with tofacitinib (-2.0-0.4 and -3.5-0.2) vs placebo (-‍0.9-‍0.4 and -1.5-1.1). Enthesitis at M6 was more common in patients with greater baseline enthesitis severity. At M6, ≤ 40% of patients with baseline LEI > 0 or SPARCC > 0 whose enthesitis had resolved by M1/M3 experienced a relapse, and < 14% of patients with baseline LEI = 0 and SPARCC = 0 had de novo enthesitis. LDA/remission rates generally increased with tofacitinib over time. Baseline LEI location was significantly associated with change from baseline in arthritis pain score, while baseline SPARCC severity was significantly associated with change from baseline in FACIT-F total and arthritis pain scores.

CONCLUSION

Tofacitinib treatment resulted in improvements in enthesitis in patients with PsA, regardless of baseline location or severity.

TRIAL REGISTRATION

NCT01877668;NCT01882439.

Consensus on targeted drug therapy for spondyloarthritis

Spondyloarthritis (SpA) is a group of chronic inflammatory diseases that predominantly involve the spine and/or peripheral joints. The clinical manifestations of SpA are highly heterogenous and complicated with various comorbidities. SpA is a disabling disease and adversely affects the quality of life of patients. Many new medications that target cytokines or pathways specific for the pathogenesis of SpA have been developed and they are becoming increasingly important in the treatment of SpA. However, identifying the target patient population and standardizing the usage of these drugs are critical issues in the clinical application of these "targeted therapeutic drugs". Under the leadership of National Clinical Research Center for Dermatologic and Immunologic Diseases (NCRC-DID), managed by Peking Union Medical College Hospital, the "Consensus on targeted drug therapy for spondyloarthritis" has been developed in collaboration with the Rheumatology and Immunology Physicians Committee, Chinese Medical Doctors Association, Rheumatology and Immunology Professional Committee, Chinese Association of Rehabilitation Medicine, and Chinese Research Hospital Association Rheumatology and Immunology Professional Committee. This consensus has been developed with evidence-based methodology and has followed the international standard for consensus development.

Consensus statements for pharmacological management, monitoring of therapies, and comorbidity management of psoriatic arthritis in the United Arab Emirates

OBJECTIVE

Psoriatic arthritis (PsA), a chronic inflammatory disease characterized by heterogeneous clinical manifestations, substantially impacts the quality of life of affected individuals. This article aims at developing consensus recommendations for the management of PsA and associated comorbidities and screening and monitoring requirements of PsA therapies in the United Arab Emirates (UAE) population.

METHODS

An extensive review of present international and regional guidelines and publications on the pharmacological management, monitoring of therapies in the context of PsA was performed. Key findings from guidelines and literature were reviewed by a panel of experts from the UAE at several meetings to align with current clinical practices. Consensus statements were formulated based on collective agreement of the experts and members of Emirates Society for Rheumatology.

RESULTS

The consensus recommendations were developed to aid practitioners in clinical decision-making with respect to dosage recommendations for pharmacological therapies for PsA, including conventional drugs, non-biologic, and biologic therapies. Consensus recommendations for therapeutic options for the treatment of PsA domains, including peripheral arthritis, axial disease, enthesitis, dactylitis, psoriasis, and nail disease, were developed. The panel emphasized the importance of monitoring PsA therapies and arrived at a consensus on monitoring requirements for PsA therapies. The expert panel proposed recommendations for the management of common comorbidities associated with PsA.

CONCLUSION

These consensus recommendations can guide physicians and healthcare professionals in the UAE in making proper treatment decisions, as well as efficiently managing comorbidities and monitoring therapies in patients with PsA.

A clinical practice guideline for the screening and assessment of enthesitis in patients with spondyloarthritis

Objective

The aim of this review is to provide guidance on the selection of approaches to the screening and assessment of enthesitis in patients with spondyloarthritis (SpA).

Methods

Twenty-four questions regarding the approaches to the screening and assessment of enthesitis and the implementation details were devised, followed by a systemic literature review. The Grading of Recommendations Assessment, Development, and Evaluation methodology was employed in the development of this guideline, with modifications to evaluate non-interventional approaches under comprehensive consideration of costs, accessibility, and evidence strength. A consensus from the voting panel was required for the inclusion of the final recommendations and the strength of each recommendation.

Results

Seventeen recommendations (including five strong recommendations) were included in this guideline. The voting panel expressed unequivocal support for the necessity of screening and assessment of enthesitis in patients with SpA. It was agreed unanimously that symptom evaluation and physical examination should serve as the initial steps to the recognition of enthesitis, whereas Maastricht Ankylosing Spondylitis Enthesitis Score is a reliable tool in both clinical trials and daily medical practice. Ultrasound examination is another reliable tool, with power Doppler ultrasound as an informative addition. Notwithstanding its high resolution, MRI is limited by the costs and relatively low accessibility, whereas radiographs had low sensitivity and therefore should be rendered obsolete in the assessment of enthesitis. PET/CT was strongly opposed in the detection of enthesitis.

Conclusion

This guideline provides clinicians with information regarding the screening and assessment of enthesitis in patients with SpA. However, this guideline does not intend on dictating choices, and the ultimate decisions should be made in light of the actual circumstances of the facilities.

Health care utilization and costs associated with functional status in patients with psoriatic arthritis

BACKGROUND: The Health Assessment Questionnaire Disability Index (HAQ-DI) has been validated and widely used in psoriatic arthritis (PsA) clinical trials for the assessment of patient functional status. Significant improvements in the HAQ-DI have been reported in response to therapeutic interventions; however, few US studies have evaluated the economic impact of functional disability in patients with PsA. OBJECTIVE: To evaluate the association of functional status with health care resource utilization (HCRU) and total health care costs in US patients diagnosed with PsA. METHODS: This retrospective study included adult patients with PsA enrolled in FORWARD between July 2009 and June 2019 who completed 1 or more HAQ-DI questionnaires between January 2010 and December 2019. Patient demographics, clinical characteristics, and patient-reported outcomes were collected from the most recent questionnaire. HCRU and total health care costs (2019 US dollars) for all hospitalizations, emergency department (ED) visits, outpatient visits, diagnostic tests, and procedures were assessed for the 6 months prior to survey completion. Negative binomial regression models (HCRU outcomes) and generalized linear models with γ distribution and log-link function (cost outcomes) were used to assess the relationship between HAQ-DI and HCRU and cost outcomes, respectively. RESULTS: A total of 828 patients with PsA who completed HAQ-DI questionnaires were included. The mean (SD) age was 58.5 (13.5) years, 72.3% were female, and 92.3% were White. The mean (SD) disease duration was 17.5 (12.4) years, and the mean (SD) HAQ-DI score at the time of the patients' most recent questionnaire was 0.9 (0.7). More severe functional disability, measured by higher HAQ-DI score, was significantly associated with increased risk (incident rate ratio [95% CI]) of hospitalizations (1.68 [1.11-2.55]), ED visits (2.09 [1.47-2.96]), outpatient visits (1.14 [1.05-1.24]), and diagnostic tests (1.42 [1.16-1.74]). There was also a significant positive association between greater HAQ-DI score and increased total annualized health care costs (incremental amount [95% CI], 1.13 [1.03-1.23]) and medical costs (1.38 [1.13-1.69]), but there was no significant association found with pharmacy costs. Total adjusted average patient medical costs increased with increasing HAQ-DI score. CONCLUSIONS: Among patients with PsA enrolled in FORWARD, more functional disability-as measured by higher HAQ-DI scores-was associated with greater HCRU and increased total health care costs. These results suggest that improving functional status in patients with PsA may reduce economic burden for health care payers and systems. DISCLOSURES: Dr Ogdie has received consulting fees from Amgen, AbbVie, Bristol Myers Squibb, Celgene, CorEvitas (formerly Corrona), Gilead, Janssen, Lilly, Novartis, Pfizer, and UCB and has received grant support from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatology Research Foundation, National Psoriasis Foundation, Pfizer (University of Pennsylvania), Amgen (FORWARD), and Novartis (FORWARD). Dr Hwang has received consulting fees from Novartis and UCB and has received grant support (5KL2TR003168-03) from the University of Texas Health Science Center at Houston Center of Clinical and Translational Sciences KL2 program. Drs Veeranki and Shafrin were employees of PRECISIONheor at the time of this analysis. Ms Portelli and Mr Sison are employees of PRECISIONheor. Ms Pedro has nothing to disclose. Dr Hass is an employee of H. E. Outcomes, providing consulting services to Novartis. Dr Hur was an employee of Novartis at the time of this analysis. Dr Kim was a postdoctoral fellow at the University of Texas at Austin and Baylor Scott and White Health, providing services to Novartis at the time of this analysis. Dr Yi is an employee of Novartis. Dr Michaud received grant funding from the Rheumatology Research Foundation at the time of this analysis. This study was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ.

Efficacy and safety of secukinumab in patients with spondyloarthritis and enthesitis at the Achilles tendon: results from a phase 3b trial

OBJECTIVE

ACHILLES aimed to demonstrate efficacy of secukinumab on Achilles' tendon enthesitis in spondyloarthritis (SpA) patients.

METHODS

Patients ≥18 years (n = 204) with active PsA or axial SpA and heel enthesitis were randomized 1:1 to secukinumab 150/300 mg or placebo up to week 24, and thereafter placebo patients were switched to secukinumab.

RESULTS

At week 24, a higher, yet statistically non-significant (P = 0.136), proportion of patients in secukinumab vs placebo reported resolution of Achilles tendon enthesitis in affected foot (42.2% vs 31.4%; odds ratio [OR] = 1.63; 95% CI: 0.87, 3.08). Proportion of patients reporting resolution of enthesitis based on Leeds Enthesitis Index was higher with secukinumab vs placebo (33.3% vs 23.5%; OR = 1.65; 95% CI: 0.85, 3.25) at week 24. Mean change from baseline in heel pain at week 24 was higher in secukinumab patients vs placebo (-2.8 [3.0] vs -1.9 [2.7]). Greater improvements with secukinumab were observed in heel enthesopathy activity and global assessment of disease activity. Imaging evaluation by local reading confirmed heel enthesitis on MRI at screening for all patients. Based on central reading, 56% presented with bone marrow oedema and/or tendinitis; according to Heel Enthesitis MRI Scoring System (HEMRIS) post hoc analysis, 76% had signs of entheseal inflammation while 86% had entheseal inflammation and/or structural changes.

CONCLUSION

A substantial proportion of patients showed no signs of inflammation on the centrally read MRIs despite a clinical diagnosis of heel enthesitis, thus highlighting that the discrepancy between the clinical and imaging assessments of enthesitis requires further investigation. Although ACHILLES did not meet the primary end point, the study reported clinically meaningful improvements in patient-related outcomes.

TRIAL REGISTRATION

clinicaltrials.gov, NCT02771210.

Effectiveness and safety of secukinumab in 608 patients with psoriatic arthritis in real life: a 24-month prospective, multicentre study

OBJECTIVES

To evaluate in a multicentric Italian cohort of patients with psoriatic arthritis (PsA) on secukinumab followed for 24 months: (1) the long-term effectiveness and safety of secukinumab, (2) the drug retention rate and minimal disease activity (MDA), (3) differences in the outcomes according to the biological treatment line: biologic-naïve patients (group A) versus multifailure (group B) patients.

METHODS

Consecutive patients with PsA receiving secukinumab were evaluated prospectively. Disease characteristics, previous/ongoing treatments, comorbidities and follow-up duration were collected. Disease activity/functional/clinimetric scores and biochemical values were recorded at baseline (T0), 6(T6), 12(T12) and 24(T24) months. Effectiveness was evaluated overtime with descriptive statistics; multivariate Cox and logistic regression models were used to evaluate predictors of drug-discontinuation and MDA at T6. Infections and adverse events were recorded.

RESULTS

608 patients (41.28% men; mean (SD) age 52.78 (11.33)) were enrolled; secukinumab was prescribed as first-line biological treatment in 227 (37.34%) patients, as second (or more)-line biological treatment in 381 (62.66%). Effectiveness of secukinumab was shown with an improvement in several outcomes, such as Ankylosing Spondylitis Disease Activity Score (T0=3.26 (0.88) vs T24=1.60 (0.69) ;p=0.02) and Disease Activity Index for Psoriatic Arthritis (T0=25.29 (11.14) vs T24=7.69 (4.51); p<0.01). At T24, group A showed lower Psoriasis Area Severity Index (p=0.04), erythrocyte sedimentation rate and C reactive protein (p=0.03 ;p=0.05) and joint count (p=0.03) compared with group B. At T24, MDA was achieved in 75.71% of group A and 70.37% of group B. Treatment was discontinued in 123 (20.23%) patients, mainly due to primary/secondary loss of effectiveness, and in 22 due to adverse events. Retention rate at T24 was 71% in the whole population, with some difference depending on secukinumab dosage (p=0.004) and gender (p=0.05).

CONCLUSIONS

In a real-life clinical setting, secukimumab proved safe and effective in all PsA domains, with notable drug retention rate.

Clinical Trials Supporting the Role of the IL-17/IL-23 Axis in Axial Spondyloarthritis

The term spondyloarthritis (SpA) encompasses a heterogeneous group of inflammatory musculoskeletal diseases with several common genetic background and clinical features, including the possible involvement of the axial skeleton with peripheral mono- or oligo- arthritis and frequently coexisting skin, eye and intestinal manifestations. When the sacroiliac joints or other parts of the spine or thoracic wall are predominantly affected at magnetic resonance or X-ray imaging with inflammatory back pain, the disease is classified as axial SpA and the therapeutic choices are significantly different compared to cases of peripheral arthritis. Moving from the narrow effectiveness and safety profiles of non-steroidal anti-inflammatory drugs, there has been a significant research effort aimed at identifying new treatments based on our better understanding of the pathogenesis of SpA. Indeed, in parallel with the solid data demonstrating that IL-17 and IL-23 are key cytokines in the development of enthesitis and spondylitis, monoclonal antibodies interfering with this pathway have been developed for the treatment of axial SpA. Furthermore, the IL-17/IL-23 axis is key to extra-articular manifestations such as inflammatory bowel disease, uveitis, and psoriasis which are frequent comorbidities of SpA. Currently available drugs act through these mechanisms recognizing IL-23 and targeting IL-17, such as secukinumab and ixekizumab. These therapeutic approaches are now envisioned in the international treatment recommendations for psoriatic arthritis with an axial phenotype as well as for ankylosing spondylitis (AS). We will provide herein a concise comprehensive overview of the clinical evidence supporting the use of these and other drugs acting on IL-23 and IL-17 in axial SpA.

The IL-23/IL-17A axis in spondyloarthritis: therapeutics informing pathogenesis?

PURPOSE OF REVIEW

To give an overview of the recently published trials relating to IL-23/IL-17 pathway in spondyloarthritis (SpA).

RECENT FINDINGS

Recent studies in psoriasis confirmed the efficacy of targeting the IL-23/IL-17 pathway, with emerging evidence from head-to-head studies suggesting functional hierarchy of these inhibitors. In psoriatic arthritis (PsA), recent studies have indicated the efficacy of inhibiting IL-23p19, in addition to IL-23p40 and IL-17A, albeit all with lower hurdle results than those seen in psoriasis. The first head-to-head study of an IL-17A and tumour necrosis factor inhibitor in PsA has also recently been published. Recent studies have demonstrated the efficacy of the IL-17A inhibitor, ixekizumab, across the axial SpA spectrum. In contrast, inhibition of IL-12/IL-23p40 and IL-23p19 both failed in axial SpA. In inflammatory bowel disease (IBD), recent studies indicate efficacy of IL-23p40 and IL-23p19 inhibition, in contrast to the previous failed studies of IL-17 inhibition.

SUMMARY

Clinical trials of IL-23/IL-17 inhibition have been transformative in psoriasis, with more mixed results in PsA and differential responses in axial SpA and IBD. These results pose challenges to our fundamental understanding of SpA pathogenesis and further head-to-head studies and more subtle evaluation of the local tissue-specific aspects will be required.

Resolution of Enthesitis by Guselkumab and Relationships to Disease Burden: 1-Year Results of Two Phase-3 Psoriatic Arthritis Studies

Objective

To further characterize the effect of guselkumab, a selective IL-23p19-subunit inhibitor approved for PsA, on enthesitis and assess relationships between enthesitis resolution and patient status/outcomes.

Methods

Adults with active PsA despite standard therapies in the phase 3 DISCOVER-1 and DISCOVER-2 studies were randomized 1:1:1 to guselkumab 100 mg every 4 weeks (Q4W); guselkumab 100 mg at week 0, week 4, Q8W; or placebo through week 20 followed by guselkumab 100 mg Q4W. Independent assessors evaluated enthesitis using the Leeds Enthesitis Index (LEI; total score 0–6). Enthesitis findings through week 24 were pre-specified to be pooled across studies; post hoc and week 52 analyses also employed pooled data.

Results

Among 1118 randomized, treated patients in DISCOVER-1 and 2 who had ≥1 LEI site evaluated, 65% had enthesitis at baseline. These patients exhibited numerically more swollen and tender joints, systemic inflammation and impaired physical function than patients without enthesitis. Guselkumab Q4W and Q8W were superior to placebo in resolving pre-existing enthesitis at week 24 (45 and 50% vs 29%; both adjusted P = 0.0301). Enthesitis resolution rates continued to rise; 58% of guselkumab-randomized patients achieved resolution at week 52, including patients with mild (LEI = 1; 70–75%), moderate (LEI = 2; 69–73%) or severe (LEI = 3–6; 42–44%) enthesitis at baseline. Among guselkumab-randomized patients with resolved enthesitis at week 24, 42% achieved minimal disease activity at week 52, vs 17% of patients with unresolved enthesitis.

Conclusion

Guselkumab resulted in higher proportions of PsA patients with resolved enthesitis by week 24, with maintenance of resolution rates through 1 year. As enthesitis confers greater disease burden, sustained resolution could portend better patient outcomes.

Clinical trial registration

DISCOVER 1 (NCT03162796) and DISCOVER 2 (NCT03158285)

The IL-17/IL-23 Axis and Its Genetic Contribution to Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory disease belonging to the family of spondyloarthropathies (SpA). PsA commonly aggravates psoriasis of the skin and frequently manifests as an oligoarthritis with axial skeletal involvement and extraarticular manifestations including dactylitis, enthesitis, and uveitis. The weight of genetic predisposition to psoriasis and PsA is illustrated by the concordance rates in monozygotic twins which clearly demonstrate that genomics is insufficient to induce the clinical phenotype. The association of PsA with several single nucleotide polymorphisms (SNPs) at the IL23R locus and the involvement of Th17 cells in the immunopathogenesis of PsA clearly put the IL-23/IL-17 axis in the spotlight. The IL-23 and IL-17 cytokines have a pivotal role in the chronic inflammation of the synovium in PsA and are also prominent in the skin lesions of those with PsA. In this review, we focus on the genetic association of the IL-23/IL-17 axis with PsA and the contribution of these master cytokines in the pathophysiology of the disease, highlighting the main cell types incriminated in PsA and their specific role in the peripheral blood, lesional skin and joints of patients. We then provide an overview of the approved biologic drugs targeting the IL-23/IL-17 axis and discuss the advantages of genetic stratification to enhance personalized therapies in PsA.