Answer： According to the definition of the US FDA, 'compared use' refers to the use outside of a clinical trial of an investigational medical product (i.e., one that has not been approved by FDA). According to the provisions of China's Drug Administration Law, drugs purchased and used for clinical diagnosis and treatment by medical institutions must be approved for production, marketing or import in accordance with the Drug Administration Law. Therefore, it can be considered that drugs that have not been approved for marketing or imported in China are limited to use in clinical trials. The Guiding Principles for Ethical Review of Clinical Trials of Drugs in China will include extended use, emergency use, or provision of medication out of sympathy as part of ethical review. This means that even if medication is provided out of sympathy, it still needs to comply with the relevant requirements for conducting clinical trials, have corresponding plans and informed consent forms, and submit them for ethical review and approval before use.