BEIJING, Feb 1 (Reuters) - As the COVID-19 pandemic evolves in China with the Omicron variant driving infections, domestic companies are racing to develop an Omicron-targetted vaccine using messenger RNA (mRNA) technology.
China's home-grown vaccines are widely considered less effective than Pfizer-BioNTech and Moderna's mRNA vaccines.
It has declined to use mRNA vaccines from abroad and has yet to approve a domestic one.
Below are the major mRNA vaccine candidates being developed in China:
WALVAX BIOTECHNOLOGY CO LTD
AWcorna, developed by Walvax, is the front runner and received an emergency use approval from Indonesia in September 2022.
Indonesia's food and drugs agency said the vaccine, previously known as ARCoV, was 83.58% effective against wild-type coronavirus strains considered common, though its efficacy dropped to 71.17% against moderate cases of the Omicron variant.
Walvax, which is based in the southwestern Chinese city of Kunming, said in June the candidate had triggered a stronger antibody response against Omicron as a booster dose than Sinovac's shot in a clinical trial.
At the time the shot, co-developed with Suzhou Abogen Biosciences and a Chinese military-backed research institution, was the most advanced Chinese mRNA candidate in terms of clinical trial progress.
It was being tested in China, Mexico and Indonesia.
Walvax said the vaccine could be transported and stored at a temperatures of from 2 Celsius to 8 Celsius, greatly reducing the cold chain challenges in developing countries.
CANSINO BIOLOGICS
On Jan. 5, Tianjin-based CanSino Biologics reported "positive" interim data for its experimental mRNA booster in a mid-stage trial and said it had begun "test production".
The vaccine, known as CS-2034, targets Omicron, and the company said it could produce 100 million doses of the vaccine during the first phase of manufacturing.
SUZHOU ABOGEN BIOSCIENCES CO
The firm said in December that it launched Phase III trials in the Philippines and the United Arab Emirates of an optimised version of the original ARCoV vaccine, targeting the BA.4/5 subvariants of Omicron.
SINOPHARM
Sinopharm said in January its biotech unit received Chinese regulatory approval for clinical trials of its mRNA COVID-19 vaccine targeting Omicron.
The unit, based in the commercial hub of Shanghai, has built a research and development platform, as well as workshops with annual production capacity of 2 billion doses of mRNA vaccine, Sinopharm said.
STEMIRNA THERAPEUTICS
It said in December that it received an emergency use authorisation from the Ministry of Health in Laos for its mRNA vaccine.
After getting approval in China it would be ready for mass production and the company is building a plant in Laos that can produce 20 million doses annually, the biotech startup said.
Compared with inactivated boosters, Stemirna's vaccine showed a 27.4-fold increase in neutralizing antibodies against the Omicron 14 days after booster immunisation.
The company, with backers including private equity fund Sequoia Capital China, said the vaccine is stable under temperature conditions of minus 15 Celsius to minus 25 Celsius with a shelf life of up to two years.
CSPC PHARMACEUTICAL GROUP LTD
The firm got approval to conduct trials of its mRNA shot in April last year, at about the same time as CanSino.
Last August, it reported a "good" safety profile for the shot, called SYS6006, and in a November 2022 filing revealed positive progress of the candidate in several clinical studies.
GUANGZHOU RIBOBIO CO LTD
It began an early stage clinical trial in China in January 2022 and said in June last year that its mRNA candidate specifically targeting Omicron has been approved for clinical trial in the Philippines.
AIM VACCINE CO LTD
It said in January 2022 its candidate appeared safe and able to trigger an immune response based on data from an early-stage Phase I trial.
Last October, it filed for a clinical trial in China of its Omicron BA.5 subvariant targeting vaccine candidate.
RNACURE
It has partnered with Walvax to develop mRNA vaccines targeting variants. It said in January 2022 it was applying for clinical trials for a candidate that showed broad-spectrum protection against variants in animal tests. (Compiled by Ethan Wang and Bernard Orr; Editing by Miyoung Kim, Robert Birsel)
