Day One Expands Pipeline with Potential First-in-Class Clinical-Stage Antibody Drug Conjugate (ADC) Targeting PTK7 in Solid Tumors for Adult and Pediatric Cancers

Core Insights - The U.S. FDA has cleared the IND application for MTX-13, now known as DAY301, which has demonstrated antitumor activity in various solid tumors during pre-clinical studies [1][8] - DAY301 targets PTK7, a protein overexpressed in multiple adult and pediatric cancers, making it a promising therapeutic target due to its limited expression in normal tissues [2][8] - Day One Biopharmaceuticals has entered an exclusive licensing agreement with MabCare Therapeutics for the development and commercialization of DAY301, with potential milestone payments totaling $1.207 billion [3][8] Company Overview - Day One Biopharmaceuticals is focused on developing targeted therapies for life-threatening diseases, particularly in pediatric cancer, addressing a significant unmet need in therapeutic development [4][8] - The company aims to redefine cancer drug development and improve outcomes for patients of all ages, collaborating with clinical oncologists and families [4][9] - The pipeline includes other treatments such as tovorafenib (OJEMDA™) and pimasertib, with plans to expand through in-licensing clinical-stage assets [9] Financial Aspects - Under the licensing agreement, Day One will receive an upfront payment of $55 million and is eligible for up to $1.152 billion in additional milestone payments, along with royalties on net sales outside Greater China [3][8] - The company expects to begin dosing the first patient in the Phase I study of DAY301 in late 2024 or early 2025 [3][8]