Background: Concerns about side effects and treatment interactions and delays may contribute to COVID-19 vaccine hesitancy amongst cancer patients. In the large prospective SerOzNET study of COVID-19 vaccine response in children and adults with cancer, vaccine beliefs, physician- and participant-reported adverse events (AE), treatment interruptions and quality of life (QoL) were studied. Methods: The Australian experience with COVID-19 gave a unique opportunity to study vaccination response in an infection- and vaccine-naive cancer population. Patients with current or recent solid or hematological malignancy, aged five and over, had serial assessments prior to and following multiple SARS-CoV-2 vaccinations. Electronic surveys were administered at baseline and after first, second and third doses to collect vaccine beliefs (Oxford Confidence and Complacency Scale), patient-reported toxicity and QoL (QLQC30 or PedsQL). Detailed toxicity data were collected at clinic visits and from medical records. Results: A total of 1385 vaccination doses were administered (93% BNT162b2), with at least 1 dose received by 499 patients, of whom only seven had known prior COVID-19 infection. Vaccine related beliefs were generally positive. There were no vaccine-related interruptions to cancer therapy. AE occurred in 95% of recipients, with the highest ranked severity being mild in 36% and moderate, severe or serious in 31%, 19% and 6% respectively. QoL showed no significant deterioration post-vaccination. Conclusion: This robust dataset provides evidence regarding safety and tolerance of SARS-CoV-2 vaccination in adults and children with cancer. Patients and families can be reassured that rates of AEs are comparable to the general population and do not impact delivery of cancer therapy or QoL.

The authors have declared no competing interest.

ACTRN: 12621001004853

Funding support from Cancer Australia, The Victorian Cancer Agency, The Leukaemia Foundation (Australia), Monash Health, and The Cancer Network of Western Australia.

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