There is an assertion that the Sinovac vaccine uses the "outdated" technology of inactivated whole viruses, and that such "next generation" technologies as mRNA vaccines (NIH/Moderna) and live adenovirus vaccines into which Covid genes are introduced (Oxford/Astra Zeneca) are preferable.

There is no scientific basis for this assertion. Killed virus technologies are currently used for effective, licensed vaccines against influenza and polio. In contrast, no human vaccine using mRNA or adenovirus vector technology has ever been licensed on the basis of well-conducted Phase III trials, and several vaccine candidates against other infectious diseases using the adenovirus vector technology have failed to protect humans.

This is not to say that these newer approaches will fail, but rather that SARS-CoV-2 vaccines based on the well-established approach used by Sinovac, as well as on the newer approaches, should all undergo evaluation in human Phase III trials if supported by preclinical evidence and human Phase I-II study data showing safety and immunogenicity—as is the case for the Sinovac vaccine.

The statement has been jointly given by Prof John D Clemens, MD Executive Director, icddr,b, Prof Jan Holmgren, MD, PhD, University of Goteborg, Sweden, Dr K Zaman, MBBS, MPH, PhD, Senior Scientist, icddr,b, Dr Firdausi Qadri, PhD, Senior Scientist, icddr,b, and Prof Allen Ross, MD, PhD, Senior Director, Infectious Diseases Division, icddr,b.

Source: https://www.thedailystar.net/opinion/news/sinovacs-covid-19-vaccine-shows-great-promise-1948749