High-quality randomized controlled trials (RCTs) are regarded as the gold standard for assessing the efficiency and safety of drugs. However, conducting RCTs is expensive and time consumed, and providing timely evidence by RCTs for regulatory agencies and medical decision-makers can be challenging, particularly for new or emerging serious diseases. Additionally, the strict design of RCTs often results in a weakly external validity, making it difficult to provide the evidence of the clinical efficacy and safety of drugs in a broader population. In contrast, large simple clinical trials (LSTs) can expedite the research process and provide better extrapolation and reliable evidence at a lower cost. This article presents the development, features, and distinctions between LSTs and RCTs, as well as special considerations when conducting LSTs, in accordance with literature and guidance principles from regulatory agencies both from China and other countries. Furthermore, this paper assesses the potential of real-world data to bolster the development of LSTs, offering relevant researchers’ insight and guidance on how to conduct LSTs.
