Brief Report: Declining Rates of SARS-CoV-2 Vaccine Uptake Among Patients With Thoracic Malignancies

• Patients with primary thoracic malignancies are at increased risk of complications and death from COVID-19. Multiple studies have demonstrated humoral immune responses to SARS-CoV-2 vaccinations in patients with cancer, though the degree of immunogenicity varies. Over the last year the United States CDC has issued recommendations for multiple additional ‘booster’ vaccine doses for patients with cancer for protection against severe disease. • In this study, we found that among 242 patients with primary thoracic malignancies who underwent initial vaccination against SARS-CoV-2, there was a marked decline in uptake of each subsequent additional vaccine dose. Specifically, among patients who received an initial mRNA-based vaccination series (mRNA-1273 or BNT162b2), 75% of eligible patients received the recommended third dose, 39% received the recommended fourth dose, and 5% received the recommended fifth dose at the time of data cutoff. Of note, we assessed serologic responses in a subset of patients receiving booster vaccinations and found that additional vaccinations increased humoral immunity, as expected. • With the recent CDC recommendation of novel bivalent mRNA-based vaccine booster doses for all individuals over the age of 12, our findings highlight the need for further understanding of the reasons behind decreased vaccine uptake and emphasize the importance of counseling by providers regarding public health recommendations for patients with lung cancer.