We are a clinical-stage biopharmaceutical company focused on the development of the next wave of medicine for the treatment of allergic and inflammatory diseases. Our lead product candidate, THB001, is a highly selective, oral small molecule inhibitor of KIT, a cell surface receptor that acts as the master survival and functional regulator of mast cells. Mast cells are a part of the immune system, and dysfunctional mast cell activity has been implicated in the pathophysiology of a broad range of allergic and other inflammatory disorders, including urticaria (hives), asthma and gastrointestinal disorders, among others. KIT inhibition has shown positive clinical responses in mast cell mediated diseases such as asthma and chronic urticaria. In our recently completed Phase 1a clinical trial, THB001 demonstrated dose-dependent reductions of serum tryptase, a key biomarker of mast cell activity, which has been shown to correlate with clinical benefit in chronic urticaria patients.

We submitted a clinical trial application, or CTA, in Europe for our dose escalation Phase 1b proof-of-concept trial in chronic inducible urticaria in May 2022, expect to initiate the trial in the second half of 2022, and expect to report initial data from this trial in the second half of 2023. We also intend to submit a CTA to support initiation of a Phase 1b trial in asthma in the first half of 2023 and expect to report initial data from this trial in the second half of 2024. We intend to submit both a CTA in Europe and an investigational new drug application, or IND, in the United States to support initiation of a Phase 2 trial in chronic spontaneous urticaria in the first half of 2024. We are also exploring development opportunities across a range of other indications where THB001 may provide benefit to patients suffering from mast cell-driven inflammation to demonstrate the “pipeline-in-a-product” potential of THB001.

Mast cells are a main driver of allergic inflammatory responses. They are present throughout the body in connective and vascularized tissues, most prominently along surface boundaries with exposure to the external environment: in the skin, the respiratory tract and the gastrointestinal tract. For many patients suffering from allergic conditions, inhibition of mast cell- derived mediators, including histamines, leukotrienes, and prostaglandins, has demonstrated insufficient therapeutic value to-date given that many mast cell-driven disorders involve multiple pro-inflammatory mediators. As a result, we believe that targeting mast cells directly through highly selective inhibition of KIT is key to achieving the clinical efficacy needed for broad symptomatic relief across a range of allergic and other inflammatory disorders.

*Note: Third Harmonic Bio has not generated any revenues. Its net loss is for the year ended Dec. 31, 2021, according to the prospectus.

(Note: Third Harmonic Bio, Inc. increased its IPO at pricing to 10.9 million shares, up from 9.0 million shares, and priced the IPO at $17 – the mid-point of its $16-to-$18 range – on Sept. 14, 2022, to raise $185.3 million. By adding 1.9 million shares and pricing the deal at the $17.00 mid-point, Third Harmonic Bio raised $32.3 million more than it would have under the terms in the prospectus. Third Harmonic Bio, Inc. disclosed terms for its IPO – 9.0 million shares at $16.00 to $18.00 to raise $153.0 million – in an S-1/A filing dated Sept. 8, 2022. Third Harmonic Bio, Inc. filed its S-1 on Aug. 23, 2022. The company filed confidential IPO documents with the SEC on May 13, 2022.)