Excellergy raises $70M to reinvent allergy treatment with multi-action drug

Biotech startup Excellergy secured $70 million to advance a new class of allergy drugs that act on the immune system in three distinct ways for faster, more comprehensive relief. This amount came from investors that include Red Tree, Samsara BioCapital, and Decheng Capital.

Why it matters: Current treatments for IgE-mediated allergies, like Xolair, are limited and slow-acting. Excellergy’s trifunctional approach could offer a breakthrough for millions with food allergies, chronic hives, and other allergic conditions.

Backstory: Founded in 2021 with backing from Red Tree Venture Capital, Excellergy is building on research from Stanford and the University of Bern. Its drug targets IgE, the antibody responsible for allergic reactions, by both removing it and suppressing the immune cell receptor it binds to.

Zoom in: The drug class is called effector cell response inhibitors (ECRIs). Early clinical trials will begin in 2026, with food allergies and urticarias as likely lead indications. Unlike Xolair, ECRIs also remove IgE already bound to receptors, without triggering immune overreaction.

Big picture: With over $1 billion invested in immunology startups this year, Excellergy joins a crowded but fast-growing field, competing with major players like Regeneron and Novartis. The company believes many patients are still under- or untreated, leaving a large untapped market.