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Background: High placebo responses have limited drug development in eosinophilic oesophagitis. The optimal configuration of trial outcomes is uncertain. Aims: To inform more efficient future trial designs, to characterise clinical, endoscopic and histologic placebo responses in eosinophilic oesophagitis randomised controlled trials (RCTs). Methods: We updated a Cochrane systematic review and meta‐analysis, searching multiple databases to January 1, 2024, to identify placebo‐controlled RCTs evaluating medical therapies for patients with eosinophilic oesophagitis. The primary outcome was the pooled proportion of study‐defined clinical, endoscopic and histologic responders and remitters randomised to placebo, using an intention‐to‐treat approach and random‐effects model. Sources of heterogeneity were explored using meta‐regression. Results: We included 25 RCTs. The pooled proportion of clinical response was 41.0% [95% CI: 29.7%–52.8%] with substantial heterogeneity (I2 = 74.9%). On meta‐regression, older age and a higher probability of being randomised to placebo reduced the likelihood of clinical response to placebo. The pooled proportion of histologic remission defined as a peak eosinophil count [PEC] ≤ 6 eosinophils per high power field [HPF] or ≤ 1 eosinophil/HPF was 4.3% [95% CI: 2.6%–6.2%] (I2 = 23.6%) and 1.3% [95% CI: 0.5%–2.5%] (I2 = 0%), respectively. The standardised mean difference in the Eosinophilic Oesophagitis Endoscopic Reference Score to placebo was −0.25 [95% CI: −0.41, −0.10]. Conclusions: Over 40% of patients in eosinophilic oesophagitis trials respond clinically to placebo, and this is associated with trial design factors such as randomisation ratio and trial population. Objective endoscopic and histologic measures are associated with very low placebo responses. [ABSTRACT FROM AUTHOR]

Inflammation is associated with, and may be causal of, a variety of ophthalmic pathologies. These pathologies are currently difficult to model in vitro because they involve complex interactions between the innate immune system, stromal cells, and other cells that normally maintain ocular tissue homeostasis. Using transscleral drainage channel fibrosis after glaucoma surgery as an example of inflammation-associated ocular fibrosis, we have assessed a simple but novel 3D cell culture system designed to reveal the immunomodulatory impacts of ocular connective tissue cells on monocytes, a major cellular component of the circulating immune system. Primary human Tenon's capsule fibroblasts derived from five unrelated patients were activated into myofibroblasts in 3D collagen matrices under isometric tension, with and without exposure to an inflammatory cytokine-enhanced milieu, and co-cultured with an immortalized human monocyte cell line (THP-1 cells). Quantitative PCR analyses were performed on 8 candidate genes to assess the impacts of inflammatory cytokines on the myofibroblasts and the monocytes in mono-cultures and compared to cells in co-culture to clearly distinguish any co-culture-induced impacts on gene expression. Our data indicate that both Tenon's capsule myofibroblasts in 3D mono-culture and THP-1 monocytes in suspension mono-culture were responsive to inflammatory cytokine stimuli. Co-culture with Tenon's capsule myofibroblasts significantly modulated the gene expression responses of THP-1 monocytes to inflammatory cytokine stimulation, indicative of an immunomodulatory "feedback" system between these cell types. Our findings provide proof of principle for the use of simple 3D co-culture systems as a means to enhance our understanding of ocular stromal cell interactions with cells of the innate immune system and to provide more informative in vitro models of inflammation-associated ophthalmic pathologies. [ABSTRACT FROM AUTHOR]