Etrasimod reduces circulating and mucosal inflammatory lymphocyte populations and alters innate immune and non-immune cell signatures in intestinal mucosa: ELEVATE UC phase 3 clinical data.

In 30 seconds

This analysis of the phase 3 ELEVATE UC randomised trials characterised blood and intestinal mucosal changes in patients with ulcerative colitis treated with etrasimod or placebo. At Week 12, etrasimod was associated with selective, partial reductions in circulating T- and B-cell subsets, with larger effects on CD4+ than CD8+ T cells and on naive and central-memory than effector-memory T cells. Biopsies showed corresponding lymphocyte reductions, fewer myeloid cells and neutrophils, and lower inflammatory signalling. Mucosal changes were most prominent among clinical remitters and included non-immune cell signatures consistent with tissue repair.

Key findings

• At Week 12, circulating T- and B-cell subsets were selectively and partially reduced with etrasimod versus placebo.
• Circulating reductions were greater for CD4+ than CD8+ T cells and for naive and central-memory than effector-memory T cells.
• Mucosal biopsies showed reductions in T- and B-cell subsets, myeloid cells and neutrophils, with downregulation of interleukin-17 and interleukin-8 signalling.
• Mucosal changes were most prominent in clinical remitters; monocyte and NK-cell numbers did not significantly change.

Why it matters

The findings link etrasimod treatment with changes in both circulating immune populations and intestinal tissue, including reduced inflammatory-cell signatures. The differences by cell subset and remission status help describe the biological response associated with treatment and clinical remission, while the absence of significant monocyte or NK-cell changes indicates that the observed effects were not uniform across immune-cell types.

What to keep in mind

The abstract reports cellular and molecular changes but does not provide effect sizes or detailed clinical outcome estimates for these analyses.