Safety and Immunogenicity of Homologous and Heterologous Adenoviral-Vectored and mRNA COVID-19 Vaccine Regimens in Radiotherapy Patients
Anussara Prayongrat,
Patjaya Noppaving,
Thitiporn Chobarporn,
Natthinee Sudhinaraset,
Nattaya Teeyapun,
Nussara Pakvisal,
Watsamon Jantarabenjakul,
Jiratchaya Sophonphan,
Chawalit Lertbutsayanukul,
Yong Poovorawan
Affiliations
Anussara Prayongrat
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand
Patjaya Noppaving
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand
Thitiporn Chobarporn
Department of Surgery, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Natthinee Sudhinaraset
Center of Excellence in Clinical Virology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Nattaya Teeyapun
Department of Medical Oncology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand
Nussara Pakvisal
Department of Medical Oncology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand
Watsamon Jantarabenjakul
Center of Excellence for Paediatric Infectious Diseases and Vaccines, Department of Paediatrics, Faculty of Medicine, Bangkok 10330, Thailand
Jiratchaya Sophonphan
HIV-NAT, Thai Red Cross AIDS Research Centre, Bangkok 10330, Thailand
Chawalit Lertbutsayanukul
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand
Yong Poovorawan
Center of Excellence in Clinical Virology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Diminished immune response after vaccination occurs in cancer patients. This observational study evaluated the immune response and safety profile after COVID-19 vaccination in radiotherapy patients. The study comprised 53 cancer patients undergoing radiotherapy and voluntarily received the COVID-19 vaccine. The two regimens were homologous ChAdOx1-S recombinant (AstraZeneca, AZ), “AZ-AZ” and heterologous “AZ-mRNA”. The seroconversion rate and anti-RBD immunoglobulin geometric mean titers (GMT) were assessed and compared with healthy controls. Adverse effects were assessed using a questionnaire. The seroconversion rate was 52.4% 1 month after the first dose with GMT 4.3 U/mL (95%CI 1.4–13). Following the second dose, the AZ-AZ group achieved 95% seroconversion rate with GMT = 188.4 U/mL (95%CI 67.1–529), which was significantly lower than the healthy cohort, GMT = 945 U/mL (95%CI 708–1261). Cancer patients in AZ-mRNA group achieved a 100% seroconversion rate with a high GMT = 1400.8 U/mL (95%CI 429.5–4566), which was significantly lower than the healthy cohort, GMT = 5169.9 U/mL (95%CI 3582.2–7461.5). Most adverse effects were mild. Our findings suggest that radiotherapy patients had fair immunogenicity after the first dose, but achieved a high seroconversion rate after the second dose with manageable adverse effects. However, their immunologic response was lower than in healthy individuals, indicating that other preventive strategies are needed.
