Attigo

Third Harmonic Bio is a clinical-stage biopharmaceutical company focused on developing next-generation oral small-molecule inhibitors of KIT, a cell surface receptor that serves as the master regulator of mast cell function and survival. Originally founded as Attigo Biotherapeutics, the company targets mast cell-mediated inflammatory diseases, including chronic spontaneous urticaria and asthma. While its initial lead candidate, THB001, faced clinical setbacks due to liver toxicity, the company is now advancing THB335, a highly selective KIT inhibitor designed to improve safety and efficacy. Third Harmonic Bio aims to provide a potent, oral alternative to injectable biologics for patients with severe allergic and inflammatory conditions.