A news report by Qu Jian from Science and Technology Daily:

The Phase I/II clinical trials of the world's first inactivated COVID-19 
vaccine, developed by Wuhan Institute of Biological Products under the China 
National Biotec Group (CNBG) affiliated to the China National Pharmaceutical 
Group (Sinopharm), produced antibodies in every participant, it was announced 
on Tuesday.

According to a meeting held simultaneously in Beijing and Henan province on 
Tuesday, the clinical trial results showed that the vaccination was safe 
without any serious adverse reaction, and after different procedures and 
different doses of vaccination were adopted, participants in the vaccine group 
all produced high titers of antibodies. 

People who received two doses of the vaccine at an interval of 28 days, saw 
their neutralizing antibody positive conversion rate reach 100%.

According to CNBG, the Phase I/II clinical trials were randomized, 
double-blind, placebo-controlled clinical studies. On April 12, the vaccine 
obtained the world's first clinical trial approval, and Phase I/II clinical 
trials were then launched in Wuzhi county of Henan province.

Under the leadership and guidance of the Henan Center for Disease Control and 
Prevention, the clinical trials were conducted for 66 consecutive days and 
obtained data on the safety and efficacy of the COVID-19 inactivated vaccine 
after the administration of the two injections. The data presented research 
results on different ages, different procedures, different doses, and different 
injection times in a relatively comprehensive manner. This is also the clinical 
COVID-19 vaccine research that has the longest time span, produces the most 
comprehensive data and obtains the best research results, thus providing 
scientific and evaluable data for epidemic prevention and control as well as 
emergency use.

CNBG said the study was designed to evaluate the safety and immunogenicity of 
the COVID-19 inactivated vaccine in healthy subjects aged from 18 to 59 for 
low, medium and high dosages and injections at intervals of 14, 21 and 28 days. 

The study focused on the changes in cellular immunity after vaccination and 
explored vaccination procedures, immunization dosage, safety, immunogenicity 
and changes in antibody levels in vivo. Up to now, all the 1,120 subjects that 
took part in the Phase I/II clinical studies have completed two injections.

For those aged 18 - 59 who received two medium-dose injections through the 
14-day and 21-day interval procedures, they had a neutralizing antibody 
positive conversion rate of 97.6%. 

For those who received two medium-dose injections at an interval of 28 days, 
the neutralizing antibody positive conversion rate reached 100%.

In response to recent new cases in Beijing and the discovery of a new genotype 
of the virus through whole-genome sequencing, some experts worry that for the 
new genotype, "the vaccine may weaken or even not work." 

However, Yang Xiaoming, chief scientist of the national "863 Program" vaccine 
project and chairman of CNBG, told Science and Technology Daily he had noticed 
the new genotype, but it is "still within the coverage of the vaccine whose 
Phase I/II unblinding occurred today", so it will not affect the effectiveness 
of the current inactivated vaccine.

CNBG also said that it is now actively developing overseas cooperation in the 
Phase III clinical research and has confirmed cooperative intentions with 
companies and institutions in various countries. It has completed building a 
high biosafety grade production workshop, which is currently the only COVID-19 
vaccine production workshop in the world meeting the requirements of biosafety 
and GMP standards and capable of meeting the needs of widespread emergency 
vaccination.

SOURCE  Science and Technology Daily