Eli Lilly is acquiring Merida Biosciences for up to $2.9 billion, adding a platform designed to attack autoimmune disease in a precise way: by hunting down and destroying the specific malfunctioning antibodies that cause it, while leaving normal immunity intact.
That selectivity is the pitch. Rather than broadly suppressing the immune system — the trade-off with many current autoimmune drugs — Merida’s approach tags pathogenic autoantibodies for destruction. Its lead program, MER511, targets the autoantibodies behind Graves’ disease and thyroid eye disease, and entered Phase 1 in late 2025. Notably, existing Graves’ treatments don’t directly target those autoantibodies.
Lilly’s immunology spree
This is Lilly’s third immunology acquisition of 2026 (of a dozen deals that year, more than any peer), funded in part by windfall profits from its obesity drugs Zepbound and Mounjaro. “We’re building our pipeline around therapies that meaningfully change the course of disease, not just its downstream effects,” said Lilly immunology research head Francisco Ramírez-Valle. The deal is expected to close by the end of 2026.
Why it matters
Autoimmune diseases are a major frontier for big pharma, and “precision” approaches that neutralize only the disease-causing antibodies — sparing the rest of the immune system — could offer better safety than broad immunosuppression. Merida, launched only in April 2025 with $121 million in venture funding, is an early-stage bet, but a strategically aimed one.