Stemcentrx raised approximately $500M, including a $250M Series G in Aug 2015 backed by Fidelity, Founders Fund and Artis Ventures, and prior Series B and other rounds. Founded in 2008, Stemcentrx developed antibody-drug conjugates targeting cancer stem cells and companion diagnostics; multiple clinical candidates entered human trials with objective responses in several tumor types. Funding supported extensive R&D, IND filings, and early clinical development. The company was later acquired its scientific programs influenced oncology pipelines and partnerships in ADC development.