Outcomes in Patients with Cancer Treated with Immunotherapy According to COVID19 Vaccination

Immune checkpoint inhibitor (ICI) monotherapy or in combination with other systemic treatment such as chemotherapy constitute the mainstay of treatment in metastatic cancers especially non-small cell lung cancer (NSCLC) and head and neck squamous cell cancer (HNSCC). Infectious vaccines administered intratumorally have been suggested to enhance anti-tumor immunity and improve host immune system function leading to better outcomes. However, no data are available on the effect of systemic administration of mRNA corona virus disease of 2019 (COVID-19) vaccines on clinical outcomes in patients treated with immunotherapy. The aim of the study is to investigate clinical outcomes in patients with metastatic NSCLC and HNSCC cancers who are treated with ICI including overall survival (OS), progression-free survival (PFS), and immune related adverse events (IRAEs) according to mRNA COVID-19 vaccination status. This exploratory study will highlight whether COVID-19 vaccination could lead to preferential outcomes and be synergistic to systemic immunotherapy or immunochemotherapy. In this IRB-approved study, we retrospectively analyzed clinical outcomes between (cohort A) of patients treated with ICI and who received at least one dose of an mRNA COVID-19 vaccine, and a historic control group of patients (cohort B) treated with ICI, and who did not receive mRNA COVID-19 vaccine and did not have documented COVID-19 infection. We included patients with metastatic NSCLC and HNSCC who were receiving ICI, either as monotherapy or in combination with chemotherapy. Patients were stratified by age, gender, ethnicity, COVID-19 vaccination status, number of vaccinations, COVID-19 infection status, treatment type (monotherapy versus combined), treatment line, and programmed-death ligand-1 (PD-L1) status. Major endpoints included overall survival, progression-free survival, and immune-related adverse events. A total of 151 patients met inclusion criteria (94 vaccinated and 57 control). Mean age at diagnosis was 62 years, the majority were female (51%), black (58.3%), and received ICI monotherapy (57.6%). There was prolonged OS in patients who received mRNA COVID-19 vaccination versus control group (p=0.04). There was no PFS difference between the two groups (p=0.13). In a multivariate analysis, patients in the COVID-19 arm were less likely to die (HR:0.049, p =0.044). There were no significant differences in the rate of IRAEs between vaccinated and non-vaccinated patients (p=0.71). In conclusion, in this sample of patients with metastatic NSCLC and HNSCC who received ICI, there was significant improvement in OS among patients in the COVID-19 arm (vaccinated patients) compared to the control group. There were no significant differences in IRAE, PFS. Further studies are required to assess whether there is a synergistic efficacy between mRNA COVID-19 vaccination and ICI.