Eli Lilly has agreed to acquire privately held Merida Biosciences for up to USD 2.875 billion in cash, comprising an undisclosed upfront and milestone-contingent consideration, with closing expected in the fourth quarter of 2026, in its thirteenth deal of the year and third immunology-focused acquisition after Ventyx Biosciences and Orna Therapeutics. The prize is not a late-stage asset but a mechanistic platform: Merida engineers Fc-based biologics that selectively bind pathogenic autoantibodies, route them to hepatic lysosomal degradation, and suppress the B-cells producing them, preserving normal humoral immunity – a departure from broad immunosuppression or indirect IgG-lowering via FcRn blockade.

Lead candidate MER511, in Phase I for Graves' disease and thyroid eye disease, targets TSH-receptor-stimulating autoantibodies and showed early reductions in pathogenic antibody titres with acceptable tolerability, while preclinical assets span food allergy, asthma, chronic spontaneous urticaria, and membranous nephropathy.