IL-23 past, present, and future: a roadmap to advancing IL-23 science and therapy.

Interleukin (IL)-23, an IL-12 cytokine family member, is a hierarchically dominant regulatory cytokine in a cluster of immune-mediated inflammatory diseases (IMIDs), including psoriasis, psoriatic arthritis, and inflammatory bowel disease. We review IL-23 biology, IL-23 signaling in IMIDs, and the effect of IL-23 inhibition in treating these diseases. We propose studies to advance IL-23 biology and unravel differences in response to anti-IL-23 therapy. Experimental evidence generated from these investigations could establish a novel molecular ontology centered around IL-23-driven diseases, improve upon current approaches to treating IMIDs with IL-23 inhibition, and ultimately facilitate optimal identification of patients and, thereby, outcomes.

Association between enthesitis/dactylitis resolution and patient-reported outcomes in guselkumab-treated patients with psoriatic arthritis.

OBJECTIVES: To evaluate the association between enthesitis resolution (ER) and dactylitis resolution (DR) and meaningful improvements in patient-reported outcomes (PROs) among biologic-naïve patients with PsA receiving guselkumab in the DISCOVER-2 study. METHODS: Enthesitis and dactylitis, characteristic lesions of PsA, were evaluated by independent assessors using the Leeds Enthesitis Index (range, 0-6) and Dactylitis Severity Score (range, 0-60). Proportions of patients with ER or DR (score = 0) among those with score > 0 at baseline were determined at weeks 24, 52, and 100. PROs included: fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-Fatigue]), pain (0-100 visual analog scale), physical function (Health Assessment Questionnaire-Disability Index [HAQ-DI]), and health-related quality of life (36-item Short-Form Health Survey physical/mental component summary [SF-36 PCS/MCS]). Meaningful responses were defined as: improvements of ≥ 4 for FACIT-Fatigue, ≥ 0.35 for HAQ-DI, and ≥ 5 for SF-36 PCS/MCS and absolute scores of ≤ 15 for minimal pain and ≤ 0.5 for normalized HAQ-DI. Associations between ER/DR status and PRO response status were tested using a Chi-square test. RESULTS: Guselkumab-treated patients with ER were more likely than those without ER to achieve minimal pain (p < 0.001), normalized HAQ-DI (p < 0.001), and PCS response (p < 0.05) at weeks 24, 52, and 100. Patients with DR were more likely than those without DR to achieve FACIT-Fatigue response at week 24 and week 52 (both p ≤ 0.01) and minimal pain at week 24 and normalized HAQ-DI at week 52 (both p ≤ 0.03). CONCLUSION: In biologic-naïve patients with active PsA treated with guselkumab, achieving ER or DR was associated with durable improvements in selected PROs, including those of high importance to patients. TRIAL REGISTRATION: ClinicalTrials.gov ( https://clinicaltrials.gov ) NCT03158285; Registered: May 16, 2017. Key Points • At week 100, 65% and 76% of guselkumab-treated patients achieved enthesitis and dactylitis resolution (ER/DR). • Achieving ER was associated with achieving DR and vice versa through the end of study. • Achieving ER or DR was associated with durable and meaningful improvements in selected patient-reported outcomes.

Bimekizumab treatment in patients with active psoriatic arthritis and prior inadequate response to tumour necrosis factor inhibitors: 52-week safety and efficacy from the phase III BE COMPLETE study and its open-label extension BE VITAL.

OBJECTIVES: To assess 52-week safety and efficacy of bimekizumab in patients with active psoriatic arthritis (PsA) and prior inadequate response/intolerance to tumour necrosis factor inhibitors. METHODS: Patients completing the 16-week phase III double-blind, placebo-controlled BE COMPLETE (NCT03896581) study entered the open-label extension, BE VITAL (NCT04009499). All patients in BE VITAL received 160 mg bimekizumab every 4 weeks. Safety and efficacy are reported to week 52. RESULTS: A total of 347/400 (86.8%) patients completed week 52. To week 52, the exposure-adjusted incidence rate/100 patient-years for ≥1 treatment-emergent adverse event (TEAE) was 126.0, and was 7.0 for serious TEAEs. The most frequent TEAEs were SARS-CoV-2 (COVID-19), oral candidiasis, nasopharyngitis and urinary tract infection. All fungal infections were mild or moderate in severity and localised; two patients discontinued the study due to oral candidiasis. No cases of active tuberculosis, uveitis or inflammatory bowel disease were reported. One sudden death occurred. Sustained efficacy was observed with bimekizumab from week 16 to |52 across clinical and patient-reported outcomes. At week 52, 51.7% bimekizumab-randomised and 40.6% placebo/bimekizumab patients (receiving bimekizumab from week 16 to 52) had ≥50% improvement in the American College of Rheumatology criteria. Complete skin clearance (Psoriasis Area and Severity Index 100) was achieved by 65.9% bimekizumab and 60.2% placebo/bimekizumab patients at week 52. Minimal disease activity was achieved by 47.2% bimekizumab and 33.1% placebo/bimekizumab patients at week 52. CONCLUSIONS: Bimekizumab demonstrated a safety profile consistent with previous reports; no new safety signals were identified. Sustained efficacy was observed from week 16 to 52.

Vaccination recommendations for adults receiving biologics and oral therapies for psoriasis and psoriatic arthritis: Delphi consensus from the medical board of the National Psoriasis Foundation.

BACKGROUND: For psoriatic patients who need to receive nonlive or live vaccines, evidence-based recommendations are needed regarding whether to pause or continue systemic therapies for psoriasis and/or psoriatic arthritis. OBJECTIVE: To evaluate literature regarding vaccine efficacy and safety and to generate consensus-based recommendations for adults receiving systemic therapies for psoriasis and/or psoriatic arthritis receiving nonlive or live vaccines. METHODS: Using a modified Delphi process, 22 consensus statements were developed by the National Psoriasis Foundation Medical Board and COVID-19 Task Force, and infectious disease experts. RESULTS: Key recommendations include continuing most oral and biologic therapies without modification for patients receiving nonlive vaccines; consider interruption of methotrexate for nonlive vaccines. For patients receiving live vaccines, discontinue most oral and biologic medications before and after administration of live vaccine. Specific recommendations include discontinuing most biologic therapies, except for abatacept, for 2-3 half-lives before live vaccine administration and deferring next dose 2-4 weeks after live vaccination. LIMITATIONS: Studies regarding infection rates after vaccination are lacking. CONCLUSION: Interruption of antipsoriatic oral and biologic therapies is generally not necessary for patients receiving nonlive vaccines. Temporary interruption of oral and biologic therapies before and after administration of live vaccines is recommended in most cases.

IL-23 induces CLEC5A+ IL-17A+ neutrophils and elicit skin inflammation associated with psoriatic arthritis.

IL-23-activation of IL-17 producing T cells is involved in many rheumatic diseases. Herein, we investigate the role of IL-23 in the activation of myeloid cell subsets that contribute to skin inflammation in mice and man. IL-23 gene transfer in WT, IL-23RGFP reporter mice and subsequent analysis with spectral cytometry show that IL-23 regulates early innate immune events by inducing the expansion of a myeloid MDL1+CD11b+Ly6G+ population that dictates epidermal hyperplasia, acanthosis, and parakeratosis; hallmark pathologic features of psoriasis. Genetic ablation of MDL-1, a major PU.1 transcriptional target during myeloid differentiation exclusively expressed in myeloid cells, completely prevents IL-23-pathology. Moreover, we show that IL-23-induced myeloid subsets are also capable of producing IL-17A and IL-23R+MDL1+ cells are present in the involved skin of psoriasis patients and gene expression correlations between IL-23 and MDL-1 have been validated in multiple patient cohorts. Collectively, our data demonstrate a novel role of IL-23 in MDL-1-myelopoiesis that is responsible for skin inflammation and related pathologies. Our data open a new avenue of investigations regarding the role of IL-23 in the activation of myeloid immunoreceptors and their role in autoimmunity.

Distinct mast cell subpopulations within and around lymphatic vessels regulate lymph flow and progression of inflammatory-erosive arthritis in TNF-transgenic mice.

Objective: Inflammatory-erosive arthritis is exacerbated by dysfunction of joint-draining popliteal lymphatic vessels (PLVs). Synovial mast cells are known to be pro-inflammatory in rheumatoid arthritis (RA). In other settings they have anti-inflammatory and tissue reparative effects. Herein, we elucidate the role of mast cells on PLV function and inflammatory-erosive arthritis in tumor necrosis factor transgenic (TNF-tg) mice that exhibit defects in PLVs commensurate with disease progression. Methods: Whole mount immunofluorescent microscopy, toluidine blue stained histology, scanning electron microscopy, and in silico bioinformatics were performed to phenotype and quantify PLV mast cells. Ankle bone volumes were assessed by µCT, while corresponding histology quantified synovitis and osteoclasts. Near-infrared indocyanine green imaging measured lymphatic clearance as an outcome of PLV draining function. Effects of genetic MC depletion were assessed via comparison of 4.5-month-old WT, TNF-tg, MC deficient KitW-sh/W-sh (cKit-/-), and TNF-tg x cKit-/- mice. Pharmacological inhibition of mast cells was assessed by treating TNF-tg mice with placebo or cromolyn sodium (3.15mg/kg/day) for 3-weeks. Results: PLVs are surrounded by MCT+/MCPT1+/MCPT4+ mast cells whose numbers are increased 2.8-fold in TNF-tg mice. The percentage of peri-vascular degranulating mast cells was inversely correlated with ICG clearance. A population of MCT+/MCPT1-/MCPT4- mast cells were embedded within the PLV structure. In silico single-cell RNA-seq (scRNAseq) analyses identified a population of PLV-associated mast cells (marker genes: Mcpt4, Cma1, Cpa3, Tpsb2, Kit, Fcer1a & Gata2) with enhanced TGFß-related signaling that are phenotypically distinct from known MC subsets in the Mouse Cell Atlas. cKit-/- mice have greater lymphatic defects than TNF-tg mice with exacerbation of lymphatic dysfunction and inflammatory-erosive arthritis in TNF-tg x cKit-/- vs. TNF-Tg mice. Cromolyn sodium therapy stabilized PLV mast cells, increased TNF-induced bone loss, synovitis, and osteoclasts, and decreased ICG clearance. Conclusions: Mast cells are required for normal lymphatic function. Genetic ablation and pharmacological inhibition of mast cells exacerbates TNF-induced inflammatory-erosive arthritis with decreased lymphatic clearance. Together, these findings support an inflammatory role of activated/degranulated peri-PLV mast cells during arthritic progression, and a homeostatic role of intra-PLV mast cells, in which loss of the latter dominantly exacerbates arthritis secondary to defects in joint-draining lymphatics, warranting investigation into specific cellular mechanisms.

Multi-omics analysis identifies IgG2b class-switching with ALCAM-CD6 co-stimulation in joint-draining lymph nodes during advanced inflammatory-erosive arthritis.

Introduction: Defective lymphatic drainage and translocation of B-cells in inflamed (Bin) joint-draining lymph node sinuses are pathogenic phenomena in patients with severe rheumatoid arthritis (RA). However, the molecular mechanisms underlying this lymphatic dysfunction remain poorly understood. Herein, we utilized multi-omic spatial and single-cell transcriptomics to evaluate altered cellular composition (including lymphatic endothelial cells, macrophages, B-cells, and T-cells) in the joint-draining lymph node sinuses and their associated phenotypic changes and cell-cell interactions during RA development using the tumor necrosis factor transgenic (TNF-Tg) mouse model. Methods: Popliteal lymph nodes (PLNs) from wild-type (n=10) and TNF-Tg male mice with "Early" (5 to 6-months of age; n=6) and "Advanced" (>8-months of age; n=12) arthritis were harvested and processed for spatial transcriptomics. Single-cell RNA sequencing (scRNAseq) was performed in PLNs from the TNF-Tg cohorts (n=6 PLNs pooled/cohort). PLN histopathology and ELISPOT along with ankle histology and micro-CT were evaluated. Histopathology of human lymph nodes and synovia was performed for clinical correlation. Results: Advanced PLN sinuses exhibited an increased Ighg2b/Ighm expression ratio (Early 0.5 ± 0.1 vs Advanced 1.4 ± 0.5 counts/counts; p<0.001) that significantly correlated with reduced talus bone volumes in the afferent ankle (R2 = 0.54, p<0.001). Integration of single-cell and spatial transcriptomics revealed the increased IgG2b+ plasma cells localized in MARCO+ peri-follicular medullary sinuses. A concomitant decreased Fth1 expression (Early 2.5 ± 0.74 vs Advanced 1.0 ± 0.50 counts, p<0.001) within Advanced PLN sinuses was associated with accumulation of iron-laden Prussian blue positive macrophages in lymph nodes and synovium of Advanced TNF-Tg mice, and further validated in RA clinical samples. T-cells were increased 8-fold in Advanced PLNs, and bioinformatic pathway assessment identified the interaction between ALCAM+ macrophages and CD6+ T-cells as a plausible co-stimulatory mechanism to promote IgG2b class-switching. Discussion: Collectively, these data support a model of flare in chronic TNF-induced arthritis in which loss of lymphatic flow through affected joint-draining lymph nodes facilitates the interaction between effluxing macrophages and T-cells via ALCAM-CD6 co-stimulation, initiating IgG2b class-switching and plasma cell differentiation of the expanded Bin population. Future work is warranted to investigate immunoglobulin clonality and potential autoimmune consequences, as well as the efficacy of anti-CD6 therapy to prevent these pathogenic events.

Bimekizumab treatment in biologic DMARD-naïve patients with active psoriatic arthritis: 52-week efficacy and safety results from the phase III, randomised, placebo-controlled, active reference BE OPTIMAL study.

OBJECTIVES: Bimekizumab (BKZ) is a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F in addition to IL-17A. BKZ treatment has demonstrated superior efficacy versus placebo (PBO) at Week 16 in biologic disease-modifying antirheumatic drug (DMARD)-naïve patients with active psoriatic arthritis (PsA). Here, we report long-term efficacy and safety to Week 52. METHODS: BE OPTIMAL comprised a 16-week, double-blind, PBO-controlled period, then 36 weeks treatment-blind. Patients were randomised 3:2:1 to subcutaneous BKZ 160 mg every 4 weeks, PBO with switch to BKZ at Week 16, or reference arm (adalimumab (ADA) 40 mg every 2 weeks). Efficacy outcomes included the American College of Rheumatology (ACR) response criteria 20/50/70, Psoriasis Area and Severity Index (PASI) 75/90/100 in patients with baseline psoriasis affecting ≥3% body surface area and minimal disease activity (MDA); non-responder imputation. RESULTS: ACR20/50/70, PASI75/90/100 and MDA responses were sustained with BKZ to Week 52, consistent with results observed at Week 16. Patients who switched to BKZ at Week 16 demonstrated improvements in efficacy with similar results to BKZ-randomised patients by Week 52.To Week 52, 555/702 (79.1%) patients had ≥1 treatment-emergent adverse event (TEAE) during BKZ treatment; 113/140 (80.7%) on ADA. On BKZ, 46 (6.6%) patients had serious TEAEs. 54 (7.7%) Candida infections occurred during BKZ treatment and 1 (0.7%) during ADA; all cases were localised and non-serious. One death occurred in a BKZ-treated patient, unrelated to treatment. CONCLUSIONS: The efficacy of BKZ in bDMARD-naïve patients with PsA was sustained from Week 16 to Week 52. BKZ was well tolerated with no new safety signals observed. TRIAL REGISTRATION NUMBER: NCT03895203.

Guselkumab Modulates Differentially Expressed Genes in Blood of Patients With Psoriatic Arthritis: Results from Two Phase 3, Randomized, Placebo-Controlled Trials.

OBJECTIVE: To evaluate gene expression in blood of patients with psoriatic arthritis (PsA) versus healthy controls and identify changes associated with guselkumab treatment. METHODS: Whole blood transcriptome profiling via paired-end RNA sequencing was conducted using samples from DISCOVER-1 and DISCOVER-2 at baseline (n = 673) and at weeks 4 and 24 from a representative subgroup that received placebo or guselkumab (n = 227 [longitudinal PsA cohort]). Baseline samples were compared with demographically matched healthy controls (n = 21). Guselkumab-mediated changes in gene expression were assessed in participants from the longitudinal PsA cohort who did versus did not achieve at least 20% improvement in American College of Rheumatology response criteria (ACR20) or at least 75% improvement in Psoriasis Area and Severity Index (PASI75). Differential gene expression was analyzed using edgeR. RESULTS: At baseline, 355 upregulated and 314 downregulated genes (PsA-associated genes) were identified in patients with PsA versus healthy controls. Upregulated genes were related to neutrophil, mononuclear cell, and CD11b+ gene sets. No cell type-specific gene sets were identified among downregulated genes. Most PsA-associated genes were modulated by guselkumab treatment. At week 24, genes downregulated by guselkumab were enriched with neutrophil, monocyte, eosinophil, and macrophage gene sets; genes upregulated by guselkumab were enriched with B cell, T cell, and natural killer cell gene sets. Reductions in expression of upregulated PsA-associated gene sets were more pronounced in ACR20 and PASI75 responders than in nonresponders. CONCLUSION: These findings suggest a dysregulation of immune cell profiles in blood from patients in the baseline PsA cohort that approached levels in healthy controls after guselkumab treatment.

Guselkumab, a Selective Interleukin-23 p19 Subunit Inhibitor, Resolves Dactylitis in Patients With Active Psoriatic Arthritis: Pooled Results Through Week 52 From Two Phase 3 Studies.

OBJECTIVE: Previous analyses of pooled DISCOVER-1 and DISCOVER-2 data through Week 24 showed significantly higher rates of dactylitis resolution in patients treated with guselkumab compared with placebo. Here, we investigate associations between dactylitis resolution and other outcomes through 1 year. METHODS: Patients were randomized 1:1:1 to receive subcutaneous injections of guselkumab 100 mg at Week 0, Week 4, and then every 4 or 8 weeks, or placebo with crossover to guselkumab at Week 24. Independent assessors determined dactylitis severity score (DSS; 0-3/digit; total = 0-60). Dactylitis resolution (DSS = 0) (prespecified) and at least 20%, at least 50%, and at least 70% DSS improvement from baseline (post hoc) were determined through Week 52 (nonresponder imputation for treatment failure through Week 24 and for missing data through Week 52). ACR50, tender/swollen joints, low disease activity (LDA) as assessed by composite indices, and radiographic progression (DISCOVER-2 only) were assessed in patients with dactylitis versus without dactylitis resolution at Week 24 and Week 52. RESULTS: Patients with dactylitis at baseline (473 of 1118) had more severe joint and skin disease than those without dactylitis (645 of 1118). At Week 52, approximately 75% of guselkumab-randomized patients with dactylitis at baseline had complete resolution; approximately 80% had at least 70% DSS improvement. Through Week 52, new-onset dactylitis (DSS ≥1) was uncommon among patients with a DSS of 0 at baseline. Guselkumab-randomized patients with dactylitis resolution were more likely to achieve ACR50, at least 50% reduction in tender and swollen joints, and LDA at Week 24 and Week 52 than those without resolution. At Week 52, patients with dactylitis resolution had numerically less radiographic progression from baseline (DISCOVER-2). CONCLUSION: Through 1 year, approximately 75% of guselkumab-randomized patients had complete resolution of dactylitis; patients exhibiting resolution were more likely to achieve other important clinical outcomes. Given the high burden of dactylitis, resolution may be associated with better long-term patient outcomes.

Multidomain Efficacy and Safety of Guselkumab Through 1 Year in Patients With Active Psoriatic Arthritis With and Without Prior Tumor Necrosis Factor Inhibitor Experience: Analysis of the Phase 3, Randomized, Placebo-Controlled DISCOVER-1 Study.

OBJECTIVE: To evaluate efficacy and safety of the interleukin-23p19-subunit inhibitor, guselkumab, in DISCOVER-1 patients with active psoriatic arthritis (PsA) by prior use of tumor necrosis factor inhibitor (TNFi). METHODS: The phase 3, randomized, placebo-controlled DISCOVER-1 study enrolled patients with active PsA (swollen joint count ≥3, tender joint count ≥3, and C-reactive protein level ≥ 0.3 mg/dl) despite standard therapies; approximately one-third could have received two or fewer prior TNFi. Patients were randomized to 100 mg of guselkumab every 4 weeks (Q4W); 100 mg of guselkumab at week 0, at week 4, and every 8 weeks (Q8W); or placebo with crossover to guselkumab Q4W at week 24. Efficacy end points of ≥20% and ≥50% improvement in individual American College of Rheumatology (ACR) criteria and achieving the minimal disease activity (MDA) components were summarized by prior TNFi status. RESULTS: In DISCOVER-1, 118 (31%) patients previously received one or two TNFi. As previously reported, rates for acheiving ≥20% improvement in the composite ACR response at week 24 and week 52 were similar in TNFi-naive and TNFi-experienced patients randomized to guselkumab Q4W (76% and 68%, respectively) and Q8W (61% and 58%, respectively). Similar trends were observed for response rates of ≥20% and ≥50% improvement in individual ACR criteria and for achieving individual MDA components at week 24; TNFi-naive patients were more likely to achieve end points related to physical function and pain than TNFi-experienced patients. Overall, response rates were maintained or increased through week 52 regardless of prior TNFi use. Through week 60 in guselkumab-treated TNFi-naive and TNFi-experienced patients, 62% and 64%, respectively, reported one or more adverse events (AEs); 4% and 6% had serious AEs, respectively. CONCLUSION: Through 1 year, 100 mg of guselkumab Q4W and Q8W provided sustained improvements across multiple domains in both TNFi-naive and TNFi-experienced patients with active PsA.

Implementation of automated behavior metrics to evaluate voluntary wheel running effects on inflammatory-erosive arthritis and interstitial lung disease in TNF-Tg mice.

BACKGROUND: Although treatment options and algorithms for rheumatoid arthritis (RA) have improved remarkably in recent decades, there continues to be no definitive cure or pharmacologic intervention with reliable long-term efficacy. For this reason, the combination of medications and healthy lifestyle modifications are essential for controlling joint disease, and extra-articular manifestations of RA, such as interstitial lung disease (ILD) and other lung pathologies, which greatly impact morbidity and mortality. Generally, exercise has been deemed beneficial in RA patients, and both patients and clinicians are motivated to incorporate effective non-pharmacologic interventions. However, there are limited evidence-based and specific exercise regimens available to support engagement in such activities for RA patients. Here, we provided the continuous opportunity for exercise to mice and implemented automated recording and quantification of wheel running behavior. This allowed us to describe the associated effects on the progression of inflammatory-erosive arthritis and ILD in the tumor necrosis factor transgenic (TNF-Tg) mouse model of RA. METHODS: Wild-type (WT; males, n=9; females, n=9) and TNF-Tg (males, n=12; females, n=14) mice were singly housed with free access to a running wheel starting at 2 months until 5 to 5.5 months of age. Measures of running included distance, rate, length, and number of run bouts, which were derived from continuously recorded data streams collected automatically and in real-time. In vivo lung, ankle, and knee micro-computed tomography (micro-CT), along with terminal micro-CT and histology were performed to examine the association of running behaviors and disease progression relative to sedentary controls. RESULTS: TNF-Tg males and females exhibited significantly reduced running distance, rate, length, and number of run bouts compared to WT counterparts by 5 months of age (p<0.0001). Compared to sedentary controls, running males and females showed increased aerated lung volumes (p<0.05) that were positively correlated with running distance and rate in female mice (WT: Distance, ρ=0.705/rate, ρ=0.693 (p<0.01); TNF-Tg: ρ=0.380 (p=0.06)/ρ=0.403 (p<0.05)). Talus bone volumes were significantly reduced in running versus sedentary males and negatively correlated with running distance and rate in TNF-Tg mice (male: ρ=-903/ρ=-0.865; female: ρ=-0.614/ρ=-0.594 (p<0.001)). Histopathology validated the lung and ankle micro-CT findings. CONCLUSIONS: Implementation of automated wheel running behavior metrics allows for evaluation of longitudinal activity modifications hands-off and in real-time to relate with biomarkers of disease severity. Through such analysis, we determined that wheel running activity increases aerated lung volumes, but exacerbates inflammatory-erosive arthritis in TNF-Tg mice. To the end of a clinically relevant model, additional functional assessment of these outcomes and studies of pain behavior are warranted.

Near-Infrared Imaging of Indocyanine Green Identifies Novel Routes of Lymphatic Drainage from Metacarpophalangeal Joints in Healthy Human Hands.

Background: Collecting lymphatic vessel (CLV) dysfunction has been implicated in various diseases, including rheumatoid arthritis (RA). RA patients with active hand arthritis exhibit significantly reduced lymphatic clearance of the web spaces adjacent to the metacarpophalangeal (MCP) joints and a reduction in total and basilic-associated CLVs on the dorsal surface of the hand by near-infrared (NIR) imaging of indocyanine green (ICG). In this pilot study, we assessed direct lymphatic drainage from MCP joints and aimed to visualize the total lymphatic anatomy using novel dual-agent relaxation contrast magnetic resonance lymphography (DARC-MRL) in the upper extremity of healthy human subjects. Methods and Results: Two healthy male subjects >18 years old participated in the study. We performed NIR imaging along with conventional- or DARC-MRL following intradermal web space and intra-articular MCP joint injections. ICG (NIR) or gadolinium (Gd) (MRL) was administered to visualize the CLV anatomy of the upper extremity. Web space draining CLVs were associated with the cephalic side of the antecubital fossa, while MCP draining CLVs were localized to the basilic side of the forearm by near-infrared indocyanine green imaging. The DARC-MRL methods used in this study did not adequately nullify the contrast in the blood vessels, and limited Gd-filled CLVs were identified. Conclusion: MCP joints predominantly drain into basilic CLVs in the forearm, which may explain the reduction in basilic-associated CLVs in the hands of RA patients. Current DARC-MRL techniques show limited identification of healthy lymphatic structures, and further refinement in this technique is necessary. Clinical trial registration number: NCT04046146.

The effect of guselkumab on inhibiting radiographic progression in patients with active psoriatic arthritis: study protocol for APEX, a Phase 3b, multicenter, randomized, double-blind, placebo-controlled trial.

BACKGROUND: Guselkumab, a fully human monoclonal antibody targeting the interleukin (IL)-23p19 subunit, is approved to treat adults with active psoriatic arthritis (PsA). In the Phase 3 DISCOVER-2 trial of 739 bilogico-naïve patients with active PsA, guselkumab 100 mg resulted in less radiographic progression, assessed via change from baseline in PsA-modified van der Heijde-Sharp (vdH-S) score, compared with placebo at week (W) 24 when given at W0, W4, and then every 4 weeks (Q4W) or Q8W. The least squares mean differences from placebo were -0.66 for guselkumab Q4W (p=0.011) and -0.43 for guselkumab Q8W (p=0.072). Reports suggest baseline C-reactive protein (CRP) and joint erosions are strongly prognostic of poor outcomes, especially radiographic progression, in PsA patients. We designed a trial (APEX) to further assess the effect of guselkumab on radiographic progression in patients with active PsA and risk factors for radiographic progression. METHODS: Patients are eligible for APEX if they have had PsA for ≥6 months and active disease (≥3 swollen and ≥3 tender joints, CRP ≥0.3 mg/dL) despite prior therapy with conventional synthetic disease-modifying antirheumatic drugs, apremilast, and/or nonsteroidal anti-inflammatory drugs, with ≥2 joints with erosions on baseline radiographs (hands and feet). The primary and major secondary endpoints are the proportion of patients achieving ≥20% improvement in American College of Rheumatology response criteria (ACR20) response at W24 and change from baseline at W24 in PsA-modified vdH-S score, respectively. Sample sizes of 350/250/350 for guselkumab Q8W/guselkumab Q4W/placebo are expected to provide >99% power to detect significant differences in W24 ACR20 response rates for each guselkumab group vs placebo, as well as ≥90% (Q4W vs placebo) and ≥80% (Q8W vs placebo) power to detect a significant difference in PsA-modified vdH-S score change at W24. A Cochran-Mantel-Haenszel test and analysis of covariance will compare treatment efficacy for the primary and major secondary endpoints, respectively. DISCUSSION: DISCOVER-2 findings informed the design of APEX, a Phase 3b study intended to further evaluate the impact of guselkumab in patients with active PsA and known risk factors for radiographic progression. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov, NCT04882098 . Registered on 11 May 2021.

The Enigmas of Lymphatic Muscle Cells: Where Do They Come From, How Are They Maintained, and Can They Regenerate?

Lymphatic muscle cell (LMC) contractility and coverage of collecting lymphatic vessels (CLVs) are integral to effective lymphatic drainage and tissue homeostasis. In fact, defects in lymphatic contractility have been identified in various conditions, including rheumatoid arthritis, inflammatory bowel disease, and obesity. However, the fundamental role of LMCs in these pathologic processes is limited, primarily due to the difficulty in directly investigating the enigmatic nature of this poorly characterized cell type. LMCs are a unique cell type that exhibit dual tonic and phasic contractility with hybrid structural features of both vascular smooth muscle cells (VSMCs) and cardiac myocytes. While advances have been made in recent years to better understand the biochemistry and function of LMCs, central questions regarding their origins, investiture into CLVs, and homeostasis remain unanswered. To summarize these discoveries, unexplained experimental results, and critical future directions, here we provide a focused review of current knowledge and open questions related to LMC progenitor cells, recruitment, maintenance, and regeneration. We also highlight the high-priority research goal of identifying LMC-specific genes towards genetic conditional- inducible in vivo gain and loss of function studies. While our interest in LMCs has been focused on understanding lymphatic dysfunction in an arthritic flare, these concepts are integral to the broader field of lymphatic biology, and have important potential for clinical translation through targeted therapeutics to control lymphatic contractility and drainage.

Bimekizumab in patients with psoriatic arthritis, naive to biologic treatment: a randomised, double-blind, placebo-controlled, phase 3 trial (BE OPTIMAL).

BACKGROUND: Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17A and IL-17F. We assessed the efficacy and safety of bimekizumab in patients with active psoriatic arthritis who were naive to biologic disease-modifying antirheumatic drugs (DMARDs). METHODS: BE OPTIMAL was a 52-week, phase 3, multicentre, randomised, double-blind, placebo-controlled, active reference (adalimumab) trial done at 135 sites (hospitals, clinics, doctors' offices, and research centres) in 14 countries. Eligible patients were 18 years or older with a documented diagnosis of adult-onset psoriatic arthritis that met the Classification Criteria for Psoriatic Arthritis for at least 6 months before screening. Participants were randomly assigned with an interactive-voice and web-response system on the basis of a predetermined randomisation schedule (3:2:1, stratified by region and bone erosion number at baseline) to bimekizumab 160 mg every 4 weeks, placebo every 2 weeks, or the reference group (adalimumab 40 mg every 2 weeks), all administered subcutaneously. At week 16, patients randomly assigned to placebo switched to bimekizumab 160 mg every 4 weeks. The primary endpoint was the proportion of patients reaching 50% or greater improvement in American College of Rheumatology criteria (ACR50) at week 16 (non-responder imputation). Efficacy analyses included all patients who were randomly assigned (intention-to-treat population); the safety analysis set comprised patients who received one or more doses of treatment. Data are presented to week 24 (preplanned analysis). This trial is registered at ClinicalTrials.gov, NCT03895203. FINDINGS: Between April 3, 2019, and Oct 25, 2021, 1163 patients were screened and 852 were randomly assigned to bimekizumab (n=431), placebo (n=281), and reference (adalimumab; n=140) groups. At week 16, significantly more patients receiving bimekizumab (189 [44%] of 431) reached ACR50 response versus placebo (28 [10%] of 281; odds ratio 7·1 [95% CI 4·6-10·9], p<0·0001; adalimumab 64 [46%] of 140). All secondary hierarchical endpoints were met. Treatment-emergent adverse events up to week 16 were reported in 258 [60%] of 431 patients receiving bimekizumab, 139 [49%] of 281 patients receiving placebo, and 83 [59%] of 140 patients receiving adalimumab. No deaths occurred. INTERPRETATION: Bimekizumab treatment had superior improvements in joint, skin, and radiographic efficacy outcomes at week 16 compared with placebo in patients with psoriatic arthritis who were naive to biologic DMARDs. The safety profile of bimekizumab, including the occurrence of fungal infections, was consistent with previous phase 3 studies in patients with plaque psoriasis, and with IL-17A inhibitors. FUNDING: UCB Pharma.

Bimekizumab in patients with active psoriatic arthritis and previous inadequate response or intolerance to tumour necrosis factor-α inhibitors: a randomised, double-blind, placebo-controlled, phase 3 trial (BE COMPLETE).

BACKGROUND: Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits interleukin (IL)-17F and IL-17A. This study compared the efficacy and safety of bimekizumab with placebo over 16 weeks in patients with active psoriatic arthritis and previous inadequate response or intolerance to tumour necrosis factor-α (TNFα) inhibitors. METHODS: BE COMPLETE was a phase 3, multicentre, randomised, double-blind, placebo-controlled trial conducted across 92 sites (including hospitals, clinics, and research centres) in 11 countries (Australia, Canada, Czech Republic, Germany, Hungary, Italy, Japan, Poland, Russia, the UK, and the USA). Eligible patients were aged 18 years or older with adult-onset psoriatic arthritis (meeting the Classification Criteria for Psoriatic Arthritis for at least 6 months before screening) with a history of inadequate response or intolerance to treatment with one or two TNFα inhibitors for either psoriatic arthritis or psoriasis. We stratified patients with active psoriatic arthritis by region and previous TNFα inhibitor use. Patients were randomly assigned (2:1) to receive subcutaneous bimekizumab 160 mg every 4 weeks or placebo by an interactive-voice and web-response system on the basis of a predetermined randomisation schedule. The primary endpoint was the proportion of patients with 50% or greater improvement in American College of Rheumatology criteria (ACR50) at week 16 (non-responder imputation). Efficacy analyses were done in the randomised population. The safety analysis set comprised patients who received one or more doses of study treatment. This trial was registered at ClinicalTrials.gov, NCT03896581, and is completed. FINDINGS: Between March 28, 2019, and Feb 14, 2022, 556 patients were screened and 400 patients were randomly assigned to bimekizumab 160 mg every 4 weeks (n=267) or placebo (n=133). The primary and all hierarchical secondary endpoints were met at week 16. 116 (43%) of 267 patients receiving bimekizumab reached ACR50, compared with nine (7%) of 133 patients receiving placebo (adjusted odds ratio [OR] 11·1 [95% CI 5·4-23·0], p<0·0001). 121 (69%) of 176 patients with psoriasis affecting at least 3% body surface area at baseline who received bimekizumab reached 90% or greater improvement in the Psoriasis Area and Severity Index (PASI90), compared with six (7%) of 88 patients who received placebo (adjusted OR 30·2 [12·4-73·9], p<0·0001). Treatment-emergent adverse events up to week 16 were reported in 108 (40%) of 267 patients receiving bimekizumab and 44 (33%) of 132 patients receiving placebo. There were no new safety signals and no deaths. INTERPRETATION: Bimekizumab treatment led to superior improvements in joint and skin efficacy outcomes at week 16 compared with placebo in patients with psoriatic arthritis and inadequate response or intolerance to TNFα inhibitors. The safety profile of bimekizumab was consistent with previous phase 3 studies in patients with plaque psoriasis, and studies of IL-17A inhibitors. FUNDING: UCB Pharma.

Guselkumab provides sustained domain-specific and comprehensive efficacy using composite indices in patients with active psoriatic arthritis.

OBJECTIVES: To evaluate the efficacy of guselkumab for the treatment of active PsA utilizing composite indices. METHODS: Data were pooled from the phase 3 DISCOVER-1 (n = 381) and DISCOVER-2 (n = 739) studies. In both studies, patients were randomized 1:1:1 to subcutaneous guselkumab 100 mg every 4 weeks (Q4W); guselkumab 100 mg at week 0, week 4, then Q8W; or placebo Q4W with crossover to guselkumab 100 mg Q4W at week 24. Composite indices used to assess efficacy through week 52 included Disease Activity Index for Psoriatic Arthritis (DAPSA), Psoriatic Arthritis Disease Activity Score (PASDAS), minimal disease activity (MDA), and very low disease activity (VLDA). Through week 24, treatment failure rules were applied. Through week 52, non-responder imputation was used for missing data. RESULTS: Greater proportions of guselkumab- than placebo-treated patients achieved DAPSA low disease activity (LDA) and remission, PASDAS LDA and VLDA, MDA, and VLDA at week 24 vs placebo (all unadjusted P < 0.05). At week 52, in the guselkumab Q4W and Q8W groups, respectively, response rates were as follows: DAPSA LDA, 54.2% and 52.5%; DAPSA remission, 18.2% and 17.6%; PASDAS LDA, 45.3% and 41.9%; PASDAS VLDA, 16.9% and 19.5%; MDA, 35.9% and 30.7%; and VLDA, 13.1% and 14.4%. In the placebo-crossover-to-guselkumab group, response rates for all composite indices increased after patients switched to guselkumab, from week 24 through week 52. CONCLUSION: Treatment with guselkumab provided robust and sustained benefits across multiple PsA domains through 1 year, indicating that guselkumab is an effective therapy for the diverse manifestations of PsA. TRIAL REGISTRATION: NCT03162796; NCT03158285.