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Guselkumab (GUS), an IL-23 antagonist, is being investigated for the treatment of IBD. GALAXI 1 is a ph2, double-blind, PBO-controlled study in pts with moderately to severely active CD with inadequate response or intolerance to conventional therapies (corticosteroid, immunosuppressant) and/or biologics (TNF antagonist, vedolizumab). Here we report early clinical outcome measures during induction with GUS vs PBO.

Pts with moderate to severe CD (CDAI score 220-450) were randomized 1:1:1:1:1 to GUS 200, 600 or 1200mg IV at Wks 0, 4, 8; ustekinumab (UST) ~6mg/kg IV at Wk 0 and 90mg SC at Wk8; or PBO IV. Clinical remission (CDAI score<150), clinical response (≥100-point reduction from baseline in CDAI score or CDAI score<150), and clinical-biomarker response (clinical response and ≥50% reduction from baseline in CRP or fecal calprotectin) were evaluated at Wks 4, 8 and 12 for pooled GUS arms vs PBO. UST was a reference arm.

Two hundred fifty pts were evaluated; about 50% failed previous biologic therapy. Baseline demographics and disease characteristics were generally similar among treatment groups (mean CD duration, 8.8yr; mean CDAI, 306.2; median CRP, 5.4mg/L; median fecal calprotectin, 594.0mg/kg). At Wk4, clinical remission was achieved in 20.0% of GUS-treated pts compared with 11.8% of PBO-treated pts. A greater proportion of GUS-treated pts achieved clinical remission compared with PBO-treated pts at Wk8 (42.0% vs 15.7%) and Wk12 (54.0% vs 15.7%). Similarly, within each subgroup of pts who failed biologic therapy(BIO-failures) or conventional therapy(CON-failures), GUS-treated pts achieved a higher rate of clinical remission at Wks 4, 8 and 12 compared with PBO (Fig 1). The proportion of pts who achieved clinical response and clinical-biomarker response was also higher at Wks 4, 8 and 12 among GUS-treated pts compared with PBO-treated pts. From Wks 4 to 8 to 12, the proportion of GUS-treated pts in clinical response increased from 44.0% to 56.0% to 66.0%, respectively, and the proportion in clinical-biomarker response increased from 26.0% to 43.3% to 48.0%. In contrast, the proportion of PBO-treated pts who achieved clinical response and clinical-biomarker response remained stable or decreased from Wks 4 to 8 to 12: 25.5% to 25.5% to 23.5% and 13.7% to 9.8% to 7.8%, respectively (Fig 2).

In pts with moderately to severely active CD, induction treatment with GUS combined treatments versus PBO resulted in higher rates of overall clinical remission, clinical-biomarker response, and clinical response as early as Wk4. This continued to increase through Wk12 with treatment. The early trend for achievement of clinical remission was also evident in sub-groups of pts who failed biologic or conventional therapy.

The gut microbiome directly affects the balance of pro-inflammatory and anti-inflammatory responses in the gut. As microbes thrive on dietary substrates, the question arises whether we can nourish an anti-inflammatory gut ecosystem. In this study, we investigated the relation between 173 dietary factors and the microbiome of 1425 individuals spanning four cohorts: Crohn’s disease, ulcerative colitis, irritable bowel syndrome and the general population.

Shotgun metagenomic sequencing was performed to profile gut microbial composition and function. Dietary intake was assessed through food frequency questionnaires. We performed unsupervised clustering to identify dietary patterns and microbial clusters. Next, linear models were conducted between dietary intake and microbial species and pathways, adding age, sex, caloric intake and sequencing read depth as covariates. Analyses were conducted per cohort, followed by a meta-analysis and heterogeneity estimation. Multiple testing correction was performed on the obtained p-values and a FDR <0.05 was defined as significance cut-off.

We identified 38 associations between dietary patterns and microbial clusters. Moreover, 61 individual foods and nutrients were associated with 61 species and 249 metabolic pathways in the meta-analysis across healthy individuals and patients with IBS, Crohn’s disease and UC (FDR<0.05, heterogeneity p-value>0.05). Processed foods and animal-derived foods were consistently associated with higher abundances of Firmicutes, Ruminococcus species of the Blautia genus and endotoxin synthesis pathways. The opposite associations were found for clusters comprising fish, nuts, bread and legumes. Moreover, while total plant protein intake was associated with a higher Bifidobacterium abundance (FDR=0.048, coef=4.98), animal-derived protein showed a negative association (FDR=1.30x10^-05, coef= -4.1). Lastly, we observed positive associations of fecal calprotectin with a fast food cluster (FDR=4.14x10^-4, coef=0.24) and a cluster comprised of high-fat meat, potatoes and gravy (FDR=0.003, coef =0.22), while the opposite was seen for clusters of fish and nuts (FDR=0.038, coef= -0.1) and bread and legumes (FDR=0.005, coef= -2.48).

We identified dietary patterns that consistently correlate with groups of bacteria with shared functional roles in both, health and disease. Moreover, specific foods and nutrients were associated with species known to infer mucosal protection and anti-inflammatory effects. A decrease in these bacteria has already been associated with both IBS and IBD. We propose microbial mechanisms through which the diet affects inflammatory responses in the gut as a rationale for future intervention studies.