Regeneron stock: Regeneron reports durable CIDEB results

Regeneron Pharmaceuticals reported on November 8 that a single subcutaneous dose of investigational CIDEBsiRNA produced sustained liver-fat reductions in adults with metabolic dysfunction-associated steatotic liver disease. The company said the findings were presented at AASLD The Liver Meeting 2026 and published simultaneously in The New England Journal of Medicine. The details come from a Regeneron Pharmaceuticals release.

CIDEB results extend pipeline focus

In the Phase 1/2 study, 30 participants received one of four CIDEBsiRNA dose levels and 10 received placebo. At week 36, liver fat reductions among treated participants ranged from 58% to 80%, compared with a mean 2.9% reduction for placebo, measured by MRI-PDFF. Liver fat fell below 5% in 62% of treated participants and in none of the placebo group.

Mean alanine aminotransferase levels declined across all dose groups, while aspartate aminotransferase changes moved in the same direction. The company said the primary goal was to assess safety and tolerability, with liver fat and liver-injury markers serving as secondary endpoints.

Clinical risk remains material

Overall adverse-event rates were generally similar between the CIDEBsiRNA and placebo groups. All events were mild or moderate except for one severe, serious hyperglycemia event in a treated participant; Regeneron said it was not caused by the study drug and was later attributed to adult-onset Type 1 diabetes. No participants discontinued treatment, and no nausea or vomiting events were reported in the CIDEBsiRNA groups.

The candidate remains investigational. Recruiting Phase 2a, Phase 2b and Phase 3 studies will test whether the early MRI-based improvements translate into durable effects on liver injury, disease progression and tissue-level outcomes.

Regeneron Pharmaceuticals stock traded at 855.75 euros on Lang & Schwarz at 16:10 CET on Friday, November 13, 2026.

US biotech shares remain part of a broader market backdrop tracked in current market reports.

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