Cancer Artificial intelligence (AI) applications are being developed to improve cancer drug discovery and administration. Moreover, AI can improve clinical trial design and therapeutic dosing strategies such as adaptive therapy, whereby patients are treated according to tumor response to avoid resistance. In a Perspective, Ho discusses how AI applications can improve cancer drug development and the challenges to be overcome. Science , this issue p. [982][1] [1]: /lookup/doi/10.1126/science.aaz3023