Safety of Upadacitinib in Immune-Mediated Inflammatory Diseases: Systematic Literature Review of Indirect and Direct Treatment Comparisons of Randomized Controlled Trials.

INTRODUCTION: Immune-mediated inflammatory diseases including rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), non-radiographic axial spondylarthritis (nr-axSpA), atopic dermatitis (AD), ulcerative colitis (UC), and Crohn's disease (CD) pose a substantial burden on patients and their quality of life. Upadacitinib is an orally administered, selective, and reversible Janus kinase inhibitor indicated for seven conditions, but data on its safety versus other active treatments are limited. A systematic literature review of indirect and direct treatment comparisons of randomized controlled trials (RCTs) was conducted to assess the safety profile of upadacitinib. METHODS: MEDLINE, Embase, and Cochrane Library databases were searched for indirect and direct treatment comparisons of RCTs that (1) included licensed upadacitinib dosages; (2) studied any of the seven conditions; (3) reported any adverse events (AEs), serious AEs (SAEs), AEs leading to discontinuation, major adverse cardiovascular event, venous thromboembolism, malignancies, infections or serious infections, and death; and (4) were published between January 2018 and August 2022. RESULTS: A total of 25 studies were eligible for inclusion. SAEs, AEs leading to discontinuation, and any AEs were commonly studied. RA was the most studied condition, followed by AD and UC. Most studies (16/25, 64%) reported no statistically significant difference in the studied safety outcomes between upadacitinib and other active treatments (e.g., tumor necrosis factor blockers, interleukin receptor antagonists, integrin receptor antagonists, T cell co-stimulation modulator), or placebo (placebo ± methotrexate or topical corticosteroids). Other studies (9/25, 36%) reported mixed results of no statistically significant difference and either statistically higher (8/25, 32%) or lower rates (1/25, 4%) on upadacitinib. CONCLUSION: Most studies suggested that upadacitinib has no statistically significant difference in the studied safety outcomes compared to active treatments or placebo in patients with RA, PsA, AS, AD, UC, and CD. A few studies reported higher rates, but findings were inconsistent with limited interpretation.

Mathematical modeling of atopic dermatitis reveals "double-switch" mechanisms underlying 4 common disease phenotypes.

BACKGROUND: The skin barrier acts as the first line of defense against constant exposure to biological, microbial, physical, and chemical environmental stressors. Dynamic interplay between defects in the skin barrier, dysfunctional immune responses, and environmental stressors are major factors in the development of atopic dermatitis (AD). A systems biology modeling approach can yield significant insights into these complex and dynamic processes through integration of prior biological data. OBJECTIVE: We sought to develop a multiscale mathematical model of AD pathogenesis that describes the dynamic interplay between the skin barrier, environmental stress, and immune dysregulation and use it to achieve a coherent mechanistic understanding of the onset, progression, and prevention of AD. METHODS: We mathematically investigated synergistic effects of known genetic and environmental risk factors on the dynamic onset and progression of the AD phenotype, from a mostly asymptomatic mild phenotype to a severe treatment-resistant form. RESULTS: Our model analysis identified a "double switch," with 2 concatenated bistable switches, as a key network motif that dictates AD pathogenesis: the first switch is responsible for the reversible onset of inflammation, and the second switch is triggered by long-lasting or frequent activation of the first switch, causing irreversible onset of systemic TH2 sensitization and worsening of AD symptoms. CONCLUSIONS: Our mathematical analysis of the bistable switch predicts that genetic risk factors decrease the threshold of environmental stressors to trigger systemic TH2 sensitization. This analysis predicts and explains 4 common clinical AD phenotypes from a mild and reversible phenotype through to severe and recalcitrant disease and provides a mechanistic explanation for clinically demonstrated preventive effects of emollient treatments against development of AD.