Clover Biopharmaceuticals became the sixth Chinese developer of a potential COVID-19 vaccine to move into human trials on Friday, launching a study in Australia that will test its vaccine with boosters.

China and the United States have faced off over the health crisis and are driving parallel efforts to get vaccines successfully approved and into large-scale production later this year.

There are currently no approved vaccines or treatments for the illness caused by the new coronavirus, but about a dozen vaccines are being trailed globally.

The virus emerged in the Chinese city of Wuhan late last year and has since spread globally, killing more than 450,000 people.

An increase in cases in China’s capital Beijing has forced authorities to study the genome of a possible new strain.

Clover’s trial, which is enrolling about 150 adult and elderly patients, will evaluate two different boosters, or adjuvants, from Britain’s GSK (GSK.L) and U.S.-based Dynavax (DVAX.O) in combination with its candidate shot, SCB-2019, the Chinese company said.

China's CanSino Biological, Sinopharm (1099.HK) and the Wuhan Institute of Biological Products are among those already testing vaccines, as are AstraZeneca (AZN.L), Moderna (MRNA.O) and Germany's CureVac. (here)

Clover said initial safety data from its study was expected in August this year, and it would aim to start broader studies by year end. Its vaccine is based on proteins called antigens that will be taken in combination with the adjuvants.(bwnews.pr/2YMttSB)

GSK, the world's largest vaccine maker, has shied away from developing its own vaccine and has instead focused efforts on contributing its adjuvant expertise in the global race. (bit.ly/3hJMY71)

Adjuvants, or efficacy boosters, are added to some vaccines to boost immune response with the aim of creating a longer immunity against an infection.

Dynavax’s booster CpG 1018, being tested with Clover’s shot, was developed as an adjuvant for the U.S. company’s Hepatitis B vaccine.