In June 2018, FDA released a Q&A to help stakeholders interpret international guidance on nonclinical evaluation of cancer drugs. The Q&A includes statements about reduction of animal use or use of in vitro alternatives in these studies. S9 Nonclinical Evaluation for Anticancer Pharmaceuticals – Questions and Answers – Guidance for Industry” is available on the FDA website. This international guidance was developed through FDA participation in the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. The guidance discussed in the Q&A is being implemented by the U.S., the European Union, Japan, Brazil, Singapore, Canada, South Korea, China, Switzerland, and Taiwan, thereby increasing global impact on the 3Rs.