tuxobertinib (BDTX-189)

P1, N=91, Terminated, Black Diamond Therapeutics, Inc. | Phase classification: P1/2 --> P1

In human recombinant CYP3A4, 13 metabolites were detected, and CYP3A4 was the primary enzyme responsible for tuxobertinib metabolism. This is the first report on the metabolism of tuxobertinib, which provided an overview of the metabolism profiles of tuxobertinib in vitro, which is helpful in understanding its safety and action.

P1/2, N=91, Terminated, Black Diamond Therapeutics, Inc. | Completed --> Terminated; The development of BDTX-189 was discontinued by the sponsor.

P1/2, N=91, Completed, Black Diamond Therapeutics, Inc. | Active, not recruiting --> Completed | Trial completion date: Dec 2023 --> Sep 2022 | Trial primary completion date: Jun 2023 --> Sep 2022

STX-721 demonstrates EGFR exon 20 mutant selectivity approaching the selectivity of Osimertinib in EGFR T790M mutants, warranting further exploration of this potential best-in-class exon 20 inhibitor in the clinic. Ba/F3: proliferation selectivity vs. EGFR WT Human cells: proliferation selectivity (vs.

P1/2, N=91, Active, not recruiting, Black Diamond Therapeutics, Inc. | Recruiting --> Active, not recruiting | N=200 --> 91

While several small molecules have been approved (mobocertinib) or are in clinical development (e.g. CLN-081, BDTX-189) none have demonstrated meaningful CNS activity and they can be associated with treatment-limiting adverse events, including wild-type (WT) EGFR-mediated toxicities. LNG-451 potently suppressed EGFR phosphorylation in tumor tissue (e.g. 99%, 3 h post 50 mg/kg dose) but had minimal-to modest suppression of phospho-EGFR in large intestine tissue (e.g. 4.2%, 3h post 50 mg/kg dose) and skin tissue (e.g 1.9%, 3h post 50 mg/kg dose). Taken together, LNG-451 is a wild-type EGFR-sparing, CNS-penetrant EGFR Ex20ins inhibitor that is expected to provide strong anti‑tumor efficacy for patients with advanced/metastatic solid cancers harboring oncogenic EGFR exon 20 insertions with reduced WT EGFR-driven toxicities.

While several small molecules have been approved (mobocertinib) or are in clinical development (e.g. CLN-081, BDTX-189) none have demonstrated meaningful CNS activity and they can be associated with treatment-limiting adverse events, including wild-type (WT) EGFR-mediated toxicities. An ex vivo imaging analysis of the brain and spinal cords from all animals at the end of the study showed a dose-dependent decrease in the bioluminescent signal in both brain and spinal cords from mice treated with LNG-451 relative to the vehicle control animals. Taken together, LNG-451 is a CNS-penetrant, wild-type EGFR-sparing, EGFR Ex20ins inhibitor that is expected to provide strong anti‑tumor efficacy for patients with advanced/metastatic solid cancers harboring oncogenic EGFR exon 20 insertions with reduced WT EGFR driven toxicities.

P1/2, N=100, Ongoing, Black Diamond Therapeutics, Inc.

Enrollment began 1/2020. Research Funding: Black Diamond Therapeutics