The COVID-19 pandemic has affected cancer clinical trials, but there is limited information about its impact. During the pandemic, from February 2020 to January 2021, 4.5% of patients treated on the neoadjuvant I-SPY 2 trial for high-risk early breast cancer experienced interruption of treatment due to COVID-19 infection, providing information on the pandemic's impact on clinical trials. While COVID-19 vaccination is expected to reduce attrition from trials, vaccine hesitancy and poor vaccine access in underserved communities are significant barriers to inclusive cancer clinical trials. Based on a recent poll, 28% of patients identifying as white said they would decline vaccination, whereas patients identifying as being of color may have less access to vaccination, related to health equity issues. Vaccine education is needed to build trust when facts are insufficient. Improved vaccine distribution is also needed. Both are essential for inclusive trials and require partnership between government and health care organizations.