Comparison of immunogenicity for Sinovac-CoronaVac vaccine vs. natural infection during cancer treatment

E. Çakır, D. Saydan, B. Gülbagcı, M. Özen, İ. Uğurlu, A. Demirci, F. Bilir, İ. Hacıbekiroglu, N. Yıldız, S. Akcali, M. Altindis, C. Varım, S. Yaylaci, C. Bilir

Department of Medical Oncology, Medicine Faculty, Sakarya University, Sakarya, Turkey. ceyhunvarim@sakarya.edu.tr

---

• Infectious Diseases

OBJECTIVE: Efficacy of the COVID-19 vaccines in cancer patients, especially during their active treatment, are lacking. Most of the studies in the literature compared the immunity in cancer patients with a cross-sectional cohort or retrospectively. Our study investigated Sinovac-CoronaVac COVID-19 vaccine immunogenicity and compared it with natural COVID-19 disease in cancer patients during their cancer therapy.

PATIENTS AND METHODS: A total of 111 patients with cancer and who are on active treatment were included in the study. This is a single-center study and was designed prospectively. Two group of patients were included in the study, natural disease and vaccinated group.

RESULTS: A total of 111 patients were included in the study, 34 of whom had natural COVID-19 disease. Antibody levels following the first dose vaccine were 0.4 (0-1.9) U/ml while after the second dose of vaccine were 2.6 (1.0-7.25) U/ml. Immunogenicity levels were 82.4% in the natural disease group and 75.8% in the vaccinated group after the second shot of the vaccine. Immunogenicity rate was significantly higher in non-chemotherapy (receiving immunotehrapy/targeted therapy or biologic agent) group compared to chemotherapy drug (92.9% vs. 63.3%, p=0.004). There was a difference between the antibody levels following the first and second vaccination [median (IQR): 0.3 (0-1.0) and 3.3 (2.0-6.7), p=0.001, respectively].

CONCLUSIONS: The present study revealed that the Sinovac-CoronaVac vaccine showed an acceptable immunogenicity following two shots in cancer patients who were receiving active systemic therapy. On the other hand, natural disease immunogenicity was higher than vaccinated group.

Free PDF Download