In Reply On behalf of my coauthors, I appreciate the thoughtful response to our article on the disparities in clinical trial access for patients with advanced-stage cancer.¹ The Letter raises important points that we would like to address. Our study identified the presence of a registered clinical trial open for enrollment at specific zip codes to determine access. As noted, the database may not have captured all clinical trials, particularly those unregistered, even though sponsors and investigators in the US are mandated to submit information to ClinicalTrials.gov. It is possible that some US trials were not listed, which could have affected the comprehensiveness of our findings. Additionally, we acknowledge that age disparities between trial participants and the diagnosed disease population exist, especially in breast, prostate, colon, and lung cancer trials, as described by Zhao et al,² with such disparities increasing over time. This is a critical area for further investigation.