BDTX-189

A Mutation Spectrum-Selective, Oral, Irreversible TKI

BDTX-189 is designed to be an orally available, irreversible small molecule inhibitor that targets undrugged oncogenic driver mutations of the ErbB kinases EGFR and HER2.

These include extracellular domain allosteric mutations of HER2, as well as EGFR and HER2 kinase domain exon 20 insertions, and additional activating oncogenic drivers of ErbB. The ErbB receptors are a group of receptor tyrosine kinases involved in key cellular functions, including cell growth and survival. These mutations are prevalent across a range of tumor types and cancers including in bladder, breast, colon, endometrial, gastric, and non-small cell lung cancer.

Currently, there are no medicines approved by the U.S. Food and Drug Administration (FDA) to target all of these oncogenic mutations with a single therapy. In preclinical models, BDTX-189 exhibited anti-tumor activity evidenced by potent tumor growth inhibition and tumor regression. Black Diamond’s IND for BDTX-189 was cleared by the FDA in December 2019 and the Company plans to start a combined Phase 1/2 clinical trial in the first half of 2020. The Phase 1 portion of the trial will evaluate escalating doses of BDTX-189 and is designed to determine the recommended Phase 2 dose and to assess preliminary indications of anti-tumor activity. The Phase 2 portion will determine the objective response rate (ORR) and duration of response in patients with solid tumors that have an allosteric HER2 mutation or EGFR or HER2 exon 20 insertion mutation using next-generation sequencing, or NGS.