BEIJING (Reuters) – China’s Walvax Biotechnology has recruited most of the 28,000 participants needed for a large clinical trial of its mRNA COVID-19 vaccine candidate, a senior company official said on Thursday.
China has yet to approve a Chinese vaccine of the novel messenger RNA (mRNA) technology and has yet to import a foreign mRNA vaccine.
The issue has become more urgent as studies have shown China’s most frequently used shots from Sinovac and Sinopharm are less effective against the highly contagious Omicron than against some previous variants.
From next week, a Phase III trial for Walvax’ potential mRNA vaccine will shift its focus from recruiting participants to identifying potential COVID-19 infections for data analysis, Walvax’s vice chairman Huang Zhen said on Thursday.
He declined to provide any timeline for when the trial could establish the efficacy of the vaccine.
“The first step is to identify all those cases and not to miss any,” Huang said in a phone call, citing concerns that some participants might not report their disease for fear of being quarantined.
Recruiting participants from overseas for the trial was slow initially, but accelerated after researchers moved the recruitment to smaller, less-vaccinated cities.
The ARCoV vaccine, which Walvax co-developed with Suzhou Abogen Biosciences and a Chinese military-backed research institution, is being tested in a Phase III trial across countries including China, Mexico and Indonesia.
Finding and analysing cases from a Phase III trial is essential to calculating a vaccine’s efficacy, which usually requires comparing the number of cases among those vaccinated and those not.
Another China-based clinical trial to test ARCoV as a booster dose has recruited more than 1,000 participants and collected blood samples for analysis, Huang said, without saying when the results could be ready.
Walvax has an annual capacity to make 200 million doses of the vaccine in the form of bulk substance, and the company intends to increase that capacity, Huang said.
(Reporting by Roxanne Liu and Ryan Woo; editing by Barbara Lewis)
