Sinovac Biotech, one of China’s coronavirus vaccine front-runners, published mixed findings from its two first clinical trials Tuesday, raising the stakes in Indonesia, which has already declared plans to roll out Sinovac’s vaccine.
While the vaccine appeared to be safe in these early clinical trials, the company reported that it generated lower levels of protective antibodies in the bloodstream compared with those arising in recovered coronavirus patients. In comparison, Moderna and Pfizer, which have separate experimental vaccines, had reported antibody levels on par with or higher than those produced in recovered coronavirus patients.
These early results put Sinovac on the back foot to prove its vaccine is effective in ongoing Phase 3 trials.
“That is a concern,” said Thomas Campbell, associate dean for clinical research at the University of Colorado, of the low antibody levels in Sinovac’s Phase 2 trial. “It’s an important point here, in terms of comparing this vaccine to, for instance, the Moderna and Pfizer vaccines.”
Indonesia, the world’s fourth-most populous country, recently made a big bet on Sinovac’s vaccine as officials grapple with a severe coronavirus outbreak. In an interview with Reuters on Friday, President Joko Widodo said the government had sought emergency authorization from the country’s food and drug agency to roll out the vaccine by the end of the year.