3565 - COVID-19 Vaccination Timing Prior to Immune Checkpoint Inhibitor Initiation and Survival Outcomes In Non-Small Cell Lung Cancer
Presenter(s)
K. M. Morgan1,2, D. Sabater Minarim3, B. J. Jacobs4, S. A. Copling5, A. Grippin6, and B. S. Rose1,2; 1VA San Diego Health Care System, La Jolla, CA, 2Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA, 3Department of Radiation Medicine and Applied Sciences, La Jolla, CA, 4Department of Radiation Medicine and Applied Sciences, University of California - San Diego, La Jolla, CA, 5McGovern Medical School, Houston, TX, 6Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Gainesville, FL
Purpose/Objective(s):
Recent reports suggest mRNA COVID-19 vaccines sensitize tumors to immune checkpoint inhibitors (ICI) therapy, with maximal immunogenic effect hypothesized within the 30 days following vaccination. We evaluated whether the timing of COVID-19 vaccination relative to ICI initiation impacts overall survival (OS) and non-COVID-related mortality in Non-Small Cell Lung Cancer (NSCLC) patients.Materials/Methods:
We conducted a retrospective analysis within the Veterans Health Administration (VHA) database of patients diagnosed with NSCLC on or after December 11, 2020 who received an mRNA COVID-19 vaccine and initiated ICI within one year of vaccination between December 11, 2020 and December 31, 2024. Outcomes were ascertained through February 1, 2026. Patients were stratified by time from most recent COVID-19 vaccination to ICI initiation: 0-30 days, 31-100 days, and 101-365 days. Covariates included age at diagnosis, staging, Charlson Comorbidity Index, race/ethnicity, marital status, smoking history, alcohol use history, gender, and year of ICI initiation. Cox proportional hazards models were used for OS and non-COVID-related death. COVID-related death was defined as a COVID-19 diagnosis within 30 days of death. As a negative control, identical analyses were performed stratifying by influenza vaccination timing. Significance was defined as p<0.05Results:
The final cohort included 2,017 patients, with COVID vaccine timing breakdown as follows: 0-30 days (n=247), 31-100 days (n=510), and 101-365 days (n=1,260). Compared to vaccination 0-30 days prior to ICI initiation, patients vaccinated 101-365 days prior had worse OS (Hazard Ratio (HR) 1.21, 95% Confidence Interval (CI) 1.02-1.44, p=0.025) and those vaccinated 31-100 days prior trended toward worse OS (HR 1.15, 95% CI 0.95-1.38, p=0.15). A similar pattern was observed for non-COVID-related death, with the 101-365 day group demonstrating worse outcomes (HR 1.21, 95% CI 1.02-1.44, p=0.028) and the 31-100 day group trending in the same direction (HR 1.15, 95% CI 0.95-1.39, p=0.15). In the influenza vaccination negative control analysis, no timing group demonstrated a significant association with OS or non-COVID-related death compared to vaccination 0-30 days prior to ICI initiation.Conclusion: COVID-19 vaccination within 30 days preceding ICI initiation was associated with improved overall survival and reduced non-COVID-related mortality in NSCLC patients compared to more distal vaccination timing. The null findings in the influenza vaccination control analysis suggest this effect may be specific to mRNA COVID-19 vaccines rather than a general vaccination phenomenon, consistent with preclinical data demonstrating mRNA vaccine-mediated tumor sensitization to immune checkpoint blockade. Prospective investigation is warranted to determine optimal vaccination-to-ICI sequencing.