China now has five vaccines, one vector and four inactivated, that have entered the first two phases of clinical trials in China, a senior scientist said on May 15. Vaccine recipients in phase II trials have reported no major adverse effects, and these vaccines are set to complete their phase II trials in July.
“As of today, vaccine development is generally progressing smoothly,” Zeng Yixin, deputy director of the National Health Commission, said in a news briefing on Friday.
Zeng said some vaccine candidates are conducting phase I and II clinical trials concurrently in China, which is considered “an innovation” in the emergency approval mechanism of the National Medical Products Administration.
Right now, 2,575 volunteers in total have been administered the five vaccines, including 539 volunteers for phase I trials, Zeng said. “We have gained preliminary data for phase I trials on the vaccines’ safety and ability to create protective antibodies.”
The phase II trials, which enrolled 2,036 volunteers, aim to further evaluate the vaccines’ safety and potency. “Some volunteers are taking more than one dose now, and relevant research is ongoing,” he said.
“We have not recorded any major adverse effects for volunteers in these trials,” he said. “If everything goes according to plan, these projects would finish their phase II trial in July.”
China also has other types of vaccines in the works, but some have adjusted their research to improve efficacy, as “creating vaccine is a technique, but it is also a scientific exploration,” Zeng said, adding more vaccine varieties are expected to be approved in June for clinical trials.
The recombinant adenovirus vector-based vaccine, developed by the Academy of Military Medical Sciences of the People’s Liberation Army and Chinese firm CanSino Bio, entered its phase II trial on April 12.
A viral vector vaccine uses a chemically weakened virus, in this case an adenovirus, to transport pieces of the pathogen into the host tissue, according to the US Department of Health and Human Services.
As for the four inactivated vaccines, two are created by the China National Biotec Group Co Ltd, one by Sinovac Research & Development Co Ltd, and the manufacturer of the last one is unannounced as of writing.
An inactivated vaccine uses a killed version of the germ that causes a disease to trigger an immune response. This tried-and-true method is incredibly safe because dead germs can’t cause illness.
Being a well-established technique, the quality of inactivated vaccines is more guaranteed and can be accepted more easily by other countries due to the robust international efficacy and safety standards in place, Wu Yuanbin, director of the bureau for social development at the Ministry of Science and Technology, said in a news briefing last month.