Eli Lilly has agreed to acquire Cambridge, Massachusetts-based Merida Biosciences, Inc., a private precision immunology company, for up to USD 2.875 billion in cash, adding a precision immunology platform led by the Phase I antibody therapeutic MER511, designed to selectively deplete pathogenic autoantibodies without broadly suppressing immune function. The deal extends Lilly's rapid immunology acquisition program, which has included multiple transactions in 2026 alone, as the US company builds a mechanism-differentiated pipeline across autoimmune and allergic disease.
Under the terms of the agreement, Lilly will pay an upfront cash amount plus contingent milestone payments, with total potential consideration capped at USD 2.875 billion. The split between upfront and milestone components was not disclosed. The all-cash transaction covers global rights to Merida's full pipeline and is subject to customary regulatory approvals, with closing expected in Q4 2026.
Merida's lead program, MER511 is an engineered TSHR-Fc biologic designed to selectively bind and clear pathogenic TSHR autoantibodies while also suppressing the B cells that produce them. The molecule is currently in Phase I development for Graves' disease and thyroid eye disease (TED). The company said the NEXUS study (NCT07305818) has generated initial Phase I data showing robust reductions in pathogenic thyroid-stimulating antibodies with a favorable early safety profile. Graves' disease affects approximately 3 million people in the US, with 25–40% developing TED. No approved therapy currently targets the autoantibodies directly. Merida's second disclosed program, MER769, is in IND-enabling studies for IgE-mediated allergic diseases including food allergy, asthma, and chronic spontaneous urticaria. Earlier-stage programs in membranous nephropathy and other immune-mediated conditions were also referenced in the announcement.
The TSHR space has attracted intensifying competition. Ethyreal Bio launched in June 2026 with USD 101 million to advance ETHY-001, a TSHR-blocking monoclonal antibody targeting both Graves' disease and TED, with first-in-human trials planned for H2 2026. Biohaven's IgG MoDE degrader BHV-1300 has reported greater than 80% reductions in TSHR autoantibodies in Phase Ib, and entered a pivotal Phase III Graves’ disease trial in June 2026. Regeneron and Immunovant are also active in the space via distinct mechanisms. Merida's differentiation rests on its Fc-engineering platform, which is designed to bind and eliminate specific pathogenic antibodies and their producing B cells through the body's natural antibody-clearance mechanisms, a precision depletion approach distinct from broad immunosuppression or FcRn inhibition.