Faculty Bibliography

OBJECTIVE:Individuals of racially and ethnically diverse backgrounds are underrepresented in psoriatic arthritis (PsA) research/clinical trials, despite evidence that their disease presentation, severity and course may be distinct. Here we aim to describe how race, ethnicity and other socioeconomic factors inform disease characteristics in PsA. METHODS:817 consecutive patients with PsA from a large, diverse metropolitan area, were enrolled in an observational, longitudinal registry. Demographics, medical history, medication use, and psoriatic disease phenotype and activity were all recorded and analyzed. RESULTS:The population was 77.4% non-Hispanic White, 2.2% Black, 7.1% Asian, and 9.9% identified as other races or multiracial, and 11.8% identified as Hispanic. Hispanic and non-White individuals had higher tender joint counts (p= 0.033) with similar swollen joint counts (p= 0.308) and medication use (p= 0.171). They also had high rates of radiographic axial disease. Hispanic individuals were significantly more likely to have higher tender joint counts (p= 0.029), higher RAPID3 scores (p= 0.004), and moderate-severe psoriasis (p= 0.010) compared with non-Hispanic White individuals. CONCLUSION/CONCLUSIONS:In this diverse cohort, 22.6% of patients identified as underrepresented racial and/or ethnic groups, mostly Asian or Hispanic. Despite similar swollen joint counts and medication use, non-white individuals have higher tender joint counts compared with white individuals. Phenotypically, they also were more likely to have radiographic axial involvement. These findings may reflect differences in PsA presentation, experience and outcomes in individuals of various racial and ethnic groups, which need to be taken into consideration in clinical care and research design.

OBJECTIVE:To evaluate whether the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) is a responsive instrument in psoriatic arthritis (PsA) and whether it differentiates between axial and peripheral disease activity in PsA. METHODS:Individuals with PsA initiating therapy in a longitudinal cohort study based in the United States were included. Axial PsA (axPsA), most often also associated with peripheral disease, was defined as fulfillment of the Assessment of Spondyloarthritis international Society axial spondyloarthritis classification criteria or presence of axial disease imaging features. Baseline BASDAI, individual BASDAI items, patient global assessment, patient pain, and Routine Assessment of Patient Index Data 3, and score changes following therapy initiation were descriptively reported. Standardized response means (SRMs) were calculated as the mean change divided by the SD of the change. RESULTS:The mean (SD) baseline BASDAI score at the time of therapy initiation was 5.0 (2.2) among those with axPsA (n = 40) and 4.8 (2.0) among those with peripheral-only disease (n = 79). There was no significant difference in patient-reported outcome scores between the groups. The mean change for BASDAI was similar among axial vs peripheral disease (-0.75 vs -0.83). SRMs were similar across axial vs peripheral disease for BASDAI (-0.37 vs -0.44) and the individual BASDAI items. CONCLUSION/CONCLUSIONS:BASDAI has reasonable responsiveness in PsA but does not differentiate between axPsA and peripheral PsA. (ClinicalTrials.gov: NCT03378336).

OBJECTIVES/OBJECTIVE:To identify phenotype clusters and their trajectories in psoriatic arthritis (PsA) and examine the association of the clusters with treatment response in a real-world setting. METHODS:In the multicentre PsA Research Consortium (PARC) study, we applied factor analysis of mixed data to reduce dimensionality and collinearity, followed by hierarchical clustering on principal components. We then evaluated the transition of PsA clusters and their response to new immunomodulatory therapy and tumour necrosis factor inhibitor (TNFi). RESULTS:Among 627 patients with PsA, three clusters were identified: mild PsA and psoriasis only (PsO) (Cluster 1, 47.4%), severe PsA and mild PsO (Cluster 2, 34.3%) and severe PsA and severe PsO (Cluster 3, 18.3%). Among 339 patients starting or changing, significant differences in response were observed (mean follow-up of 0.7 years, SD 0.8), with Cluster 3 showing the largest improvements in cDAPSA and PsAID. No differences were found among those starting TNFi (n=218). cDAPSA remission and PsAID patient acceptable symptom state were achieved in 10% and 54%, respectively. Clusters remained stable over time despite treatment changes, though some transitions occurred, notably from Cluster 3 to milder clusters. CONCLUSION/CONCLUSIONS:Data-driven clusters with distinct therapy responses identified in this real-world study highlight the extensive heterogeneity in PsA and the central role of psoriasis and musculoskeletal severity in treatment outcomes. Concurrently, these findings underscore the need for better outcome measures, particularly for individuals with lower disease activity.

The increasing prevalence of autoimmune and immune-mediated diseases (AIMDs) underscores the need to understand environmental factors that contribute to their pathogenesis, with the microbiome emerging as a key player. Despite significant advancements in understanding how the microbiome influences physiological and inflammatory responses, translating these findings into clinical practice remains challenging. This viewpoint reviews the progress and obstacles in microbiome research related to AIMDs, examining molecular techniques that enhance our understanding of microbial contributions to disease. We discuss significant discoveries linking specific taxa and metabolites to diseases such as rheumatoid arthritis, systemic lupus erythematosus and spondyloarthritis, highlighting the role of gut dysbiosis and host-microbiome interactions. Furthermore, we explore the potential of microbiome-based therapeutics, including faecal microbiota transplantation and pharmacomicrobiomics, while addressing the challenges of identifying robust microbial targets. We advocate for integrative, transdisease studies and emphasise the need for diverse cohort research to generalise findings across populations. Understanding the microbiome's role in AIMDs will pave the way for personalised medicine and innovative therapeutic strategies.

OBJECTIVE:Psoricatic disease remains underdiagnosed and undertreated. We developed and validated a suite of novel, smartphone sensor-based assessments that can be self-administered to measure cutaneous and musculoskeletal signs and symptoms of psoriatic disease. METHODS:Participants with psoriasis, psoriatic arthritis, or healthy controls were recruited between June 5, 2019, and November 10, 2021, at two academic medical centers. Concordance and accuracy of digital measures and image-based machine learning models were compared to their analogous clinical measures from trained rheumatologists and dermatologists. RESULTS:assessment categorized physician-assessed upper extremity involvement, considering joint tenderness or enthesitis (AUROC = 0.68 (0.47-0.85)). CONCLUSION/CONCLUSIONS:The Psorcast digital assessments achieved significant clinical validity, although they require further validation in larger cohorts before use in evidence-based medicine or clinical trial settings. The smartphone software and analysis pipelines from the Psorcast suite are open source and freely available.

Psoriatic arthritis (PsA) is a systemic chronic inflammatory disease that develops in up to 30% of patients with psoriasis. Mixed data variably support the potential ability to "prevent" and/or delay PsA through use of systemic therapies in psoriasis patients. Though intriguing, almost all of these studies are retrospective in nature, and hold substantial limitations and potential biases that challenge the ability to meaningfully interpretation their results. Thus, the authors believe prospective observational and interventional studies are crucial to understanding our ability to truly modify the transition from psoriasis to psoriatic arthritis and delay or prevent PsA onset.

Inflammatory epithelial diseases are spurred by the concomitant dysregulation of immune and epithelial cells. How these two dysregulated cellular compartments simultaneously sustain their heightened metabolic demands is unclear. Single-cell and spatial transcriptomics (ST), along with immunofluorescence, revealed that hypoxia-inducible factor 1α (HIF1α), downstream of IL-17 signaling, drove psoriatic epithelial remodeling. Blocking HIF1α in human psoriatic lesions ex vivo impaired glycolysis and phenocopied anti-IL-17 therapy. In a murine model of skin inflammation, epidermal-specific loss of HIF1α or its target gene, glucose transporter 1, ameliorated epidermal, immune, vascular, and neuronal pathology. Mechanistically, glycolysis autonomously fueled epithelial pathology and enhanced lactate production, which augmented the γδ T17 cell response. RORγt-driven genetic deletion or pharmacological inhibition of either lactate-producing enzymes or lactate transporters attenuated epithelial pathology and IL-17A expression in vivo. Our findings identify a metabolic hierarchy between epithelial and immune compartments and the consequent coordination of metabolic processes that sustain inflammatory disease.

BACKGROUND:Tumor necrosis factor inhibitors (TNFi) are frequently chosen as the first biologic for patients with psoriatic arthritis (PsA). Given that many patients with PsA are TNFi inadequate responders (TNF-IR; either inadequate efficacy or intolerance), treatments utilizing alternative mechanisms of action are needed. In phase 3 studies, the fully human interleukin (IL)-23p19 subunit-inhibitor, guselkumab, was efficacious in patients with active PsA, including TNFi-IR. Efficacy was generally consistent between TNFi-naïve and TNFi-experienced cohorts; however, in the latter, higher response rates have been observed with the Q4W dosing regimen relative to the Q8W dosing regimen for some endpoints, suggesting the need to evaluate whether more frequent dosing may provide an incremental clinical benefit for TNFi-IR patients. METHODS:The phase 3b SOLSTICE study will assess guselkumab efficacy and safety in TNFi-IR PsA patients. Eligibility criteria include a PsA diagnosis for ≥ 6 months; active disease (≥ 3 swollen, ≥ 3 tender joints, C-reactive protein ≥ 0.3 mg/dL); and inadequate efficacy with, and/or intolerance to, one prior TNFi. Participants will be randomized 1:1:1 to guselkumab Q4W or Q8W or placebo→guselkumab Q4W (at Week 24). The primary endpoint is the proportion of patients achieving ≥ 20% improvement in the American College of Rheumatology criteria (ACR20) at Week 24. Major secondary endpoints include ACR50, ACR70; an Investigator's Global Assessment (IGA) of psoriasis score of 0/1 plus ≥ 2-grade reduction and ≥ 90% improvement in Psoriasis Area and Severity Index (both among patients with ≥ 3% body surface area affected by psoriasis and baseline IGA ≥ 2); minimal/very low disease activity; and changes from baseline in Health Assessment Questionnaire-Disability Index, the 36-item Short-Form Health Survey Physical Component Summary, and Functional Assessment of Chronic Illness Therapy-Fatigue scores. The target sample size (N = 450) is estimated to provide > 90% power in detecting differences between each guselkumab group and the placebo group for the primary endpoint assuming a 2-sided α = 0.05. Cochran-Mantel-Haenszel testing and analyses of covariance will be used to compare efficacy for binary and continuous endpoints, respectively. DISCUSSION/CONCLUSIONS:Findings from the phase 3b SOLSTICE study, the design of which was informed by results from previously conducted phase 3 studies, is expected to provide important efficacy and safety information on guselkumab therapy in TNFi-IR patients with PsA. TRIAL REGISTRATION/BACKGROUND:This trial was registered at ClinicalTrials.gov, NCT04936308, on 23 June 2021.