Company: DAWN
Filing Date: 2025-02-25
Form Type: 10-K
Source: 0000950170-25-026654
Chunk: 63

Company: Day One Biopharmaceuticals, Inc.
Filing Date: 2025-02-25
Form: 10-K
Item: Item 1
Chunk 63
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-13 or CB-002). DAY301 is a novel Antibody Drug Conjugate, or ADC, targeting protein-tyrosine kinase 7, or PTK7. In pre-clinical studies, DAY301 showed antitumor activity in a wide range of solid tumors. DAY301 targets PTK7, a highly-conserved, catalytically inactive transmembrane protein that is overexpressed in multiple adult cancers, including esophageal, ovarian, lung, and endometrial cancer, as well as pediatric cancers such as neuroblastoma, rhabdomyosarcoma and osteosarcoma. In 

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April 2024, the FDA cleared the investigational new drug application for DAY301. In January 2025, we cleared the first cohort (a single-patient accelerated titration cohort) in the Phase 1a portion of the DAY301 Phase 1a/b clinical trial.

We believe our business development capabilities combined with our extensive experience in oncology drug development and deep ties within the research and patient advocacy communities, particularly within the pediatric setting, positions us to be a leader in identifying, acquiring and developing therapies for patients of all ages. We hold exclusive rights to develop tovorafenib and VRK1 for all therapeutic areas worldwide and DAY301 for all therapeutic areas worldwide, excluding Greater China, subject to certain milestone and royalty payments. Further, we hold exclusive rights to commercialize tovorafenib in the United States subject to royalty payments. Pursuant to the Ipsen License Agreement, we licensed to Ipsen, on an exclusive basis, the right to commercialize tovorafenib outside of the United States, in exchange for certain milestone and royalty payments.

We seek to identify, acquire and develop first- or best-in-class products and product candidates that target high-value oncogenic drivers in childhood and adult cancers with high unmet need. The following table summarizes our product and product candidate pipeline.

Our first commercial product, tovorafenib, is an oral, brain-penetrant, highly selective type II RAF kinase inhibitor that inhibits both monomeric and dimeric RAF kinase. Approved BRAF products such as vemurafenib and encorafenib are referred to as type I RAF inhibitors, which only inhibit RAF monomers and are therefore limited to use in BRAF V600-altered tumors. Unlike type I RAF inhibitors, tovorafenib has not been shown to cause paradoxical activation in RAF wild-type cells at clinically active doses – a phenomenon