OBJECTIVE： To provide a reference for the use and management of unregistered drugs in China. METHODS： A historical review and evaluation was conducted for the legislative process of drug trial rights in the United States， and the differences and links between the drug trial rights and the previous extended sympathetic drug system were compared. RESULTS & CONCLUSIONS： At present， 41 states in the United States have completed the drug right to try law legislation. In 2018， the US Congress passed the federal legislation on drug right to try law. The right to drug right to try law has evolved from the development of sympathetic drugs， both of which are dedicated to establishing a new path beyond clinical trials to facilitate end-stage patients access to research drugs， so both have obvious similarity. However， the drug right to try law is committed to requiring medical decisions to be returned to patients and doctors， and to the exclusion of the US Food and Drug Administration. In the case of extended sympathetic drug system， the US Food and Drug Administration is committed to “balancing the maximum benefit with the minimum damage”. The two are significantly different in terms of supervision， patient criteria， duration， responsibility distribution， and informed consent. The implementation of the right to drug right to try law has brought hope to patients in the end stage， but it has not given them more opportunities for survival； and it is especially important to correctly guide the masses to make choices rationally.