DALIAN, China -- Major Chinese drugmakers are rushing to expand production capacity for COVID-19 vaccines to aid inoculation drives around the world, but mounting doubts over how well their shots work may cloud global demand down the line.
Hammering sounds reverberated across a Beijing construction site one June day as workers put up walls for a new Sinopharm-affiliated vaccine factory. "Construction is going on 24 hours a day so the plant can go online July 1," a security guard said.
Sinopharm calls the plant its "birthday present" to the Chinese Communist Party, which celebrates its 100th anniversary Thursday. The company is on track to roughly quintuple total output capacity from March to 5 billion doses a year, including a Wuhan factory and an existing facility in Beijing.
Nor is Sinopharm the only Chinese player expanding production. Sinovac Biotech launched a third plant in Beijing this April, doubling annual capacity to 2 billion doses. CanSino Biologics began operating a joint-venture factory in Shanghai this June.
These moves come as China steps up its vaccine diplomacy, mainly among participants in its Belt and Road infrastructure-building initiative. It has supplied shots to roughly 80 countries so far in Asia, Africa and elsewhere.
However, confidence in Chinese vaccines has been undercut worldwide.
J.P. Morgan Asset Management recently reported that nine countries, including the U.S. and the U.K., saw new cases plunge after administering the Pfizer, Moderna and AstraZeneca vaccines to at least 40% of the population.
But among eight countries using the Sinopharm shot, new cases decreased only in Hungary. Others -- like Bahrain, the Maldives and Seychelles -- saw no improvement.
Bahrain and the United Arab Emirates, which both administered Sinopharm vaccines to their populations, began offering the Pfizer shot as a booster after suffering new waves of infections. Chile continues to experience widespread infections despite importing and administering large numbers of Sinovac shots.
The Sinopharm vaccine is 78% effective for those aged 18 to 59, but its efficacy among older individuals is unknown, according to the World Health Organization. The Sinovac shot has ranged from 50% to 84%, depending on the country. Meanwhile, the Pfizer and Moderna vaccines have been found to be more than 90% effective.
Whether based on the WHO data or the companies' own, "the protection efficacies for Sinovac and Sinopharm COVID-19 vaccines are lower than those from Pfizer and Moderna," said Lu Shan, a professor at the University of Massachusetts Medical School. "It is due to the technology difference."
The major Chinese vaccines use inactivated viruses, similar to the flu shot and other conventional vaccines. The Pfizer and Moderna shots use messenger RNA technology, delivering genetic code for part of the coronavirus to recipient cells. mRNA and other nucleic acid vaccines "can induce better antibody responses," Lu said.
Sinopharm executive Yang Xiaoming has told Chinese media that the company's decision to go the inactivated route enabled it to develop a vaccine so quickly, since it already had years of experience in the technology. Subsidies and other government support shortened the timeline as well.
But not everyone endorses this approach. "The novel coronavirus reproduces more slowly inside the human body than the flu virus, so some say that inactivated vaccines are not a good fit," said Kazuhiko Fuji, a consulting fellow at Japan's Research Institute of Economy, Trade and Industry.
"U.S. and European drugmakers likely decided against the option because it would not have been as effective," he said.
Chinese pharmaceutical companies are still playing catch-up with the U.S. and European players that have long dominated the market. For example, more than 90% of Sinopharm's roughly 590 billion yuan ($91 billion) in annual revenue comes through its wholesale and pharmacy business in China, with its drugmaking business supplying just a few percent. It also lags in cutting-edge technology and appears to have fallen short on efficacy by rushing out a vaccine.
Some Chinese players are working on mRNA vaccines, like Yunnan Walvax Biotechnology in partnership with the Academy of Military Medical Sciences. But the shot is still in clinical trials, and its efficacy and release date have yet to be determined.
China is expected to top the world in COVID-19 vaccine production this year with about 6.5 billion doses, significantly outpacing the 4.5 billion expected in the second-ranked U.S. But without confidence in the Chinese products, demand from abroad will wane and leave capacity at risk of going to waste.