Day One Biopharmaceuticals, Inc. is a commercial-stage biopharmaceutical company focused on developing and commercializing targeted therapies for people of all ages with life-threatening diseases. The Company partners with clinical oncologists, families, and scientists to identify, acquire, and develop cancer treatments. The Company’s commercial product, OJEMDA (tovorafenib), is an oral, brain-penetrant, selective type II rapidly accelerated fibrosarcoma (RAF) kinase inhibitor of mutant BRAF V600, wild-type BRAF, and wild-type CRAF kinases. Its pipeline product candidates include DAY301 and VRK1 program. The DAY301 candidate is a PTK7 targeted ADC composed of a novel humanized anti-PTK7 immunoglobulin G1 monoclonal antibody (mAb), conjugated with a topoisomerase I inhibitor through a stable and hydrophilic modified valine-alanine (VA) cleavable linker. Its VRK1 program is a novel target involved in the regulation of cell division and DNA damage repair.