A health-care worker prepares a syringe to give a volunteer a dose of a vaccine produced by China’s Sinopharm during its trial at the Clinical Studies Center of the Cayetano Heredia University in Lima, Peru, on Dec. 9. (Ernesto Benavides/AFP/Getty Images)

In the race to vaccinate the world, China and Russia appear headed to becoming international players, as countries buy up doses and push ahead with approvals even before the release of crucial trial data.

Although both countries’ coronavirus vaccine efforts were initially viewed with skepticism, a growing list of nations remains eager to work with Beijing and Moscow to slow the virus’s deadly spread.

Much of this has to do with scarcity. Rich countries have snapped up most of the early doses of the promising vaccines by U.S.-based Moderna and Pfizer, which is working with Germany’s BioNTech. A multilateral effort to equitably distribute doses is moving slowly. For some, China and Russia are the only immediate option.

It also reflects a growing sense that the Chinese and Russian vaccines show some scientific promise and could play a role in ending the pandemic — even as questions about safety and transparency persist.

“The idea that the Russians and Chinese are just not as good at this as we are is just vaccine nationalism,” said Naor Bar-Zeev, an infectious-disease physician and statistical epidemiologist who is an associate professor at the Johns Hopkins Bloomberg School of Public Health.

“There’s no reason to think these vaccines won’t work,” he said. “But we have not seen Phase 3.”

The latest on the pandemic around the world

The view of China’s and Russia’s vaccines remains mixed, however.

Cambodian Prime Minister Hun Sen said Tuesday that his country is not ordering a vaccine candidate developed by the Chinese biotech firm Sinovac because it has not been certified by a global body. “Cambodia is not a dustbin . . . and is not a place for a vaccine trial,” he said.

But the questions over China’s and Russia’s candidates have not stopped other countries from moving forward with deals, approvals and vaccinations.

Moscow began distributing the Sputnik V covid-19 shot via 70 clinics on Dec. 5, marking Russia's first mass vaccination against the disease. (Video: Reuters)

Last week, the United Arab Emirates approved a vaccine from China’s Sinopharm for use, claiming it is 86 percent effective without providing much detail. Bahrain quickly followed suit.

Brazil’s most populous state, São Paulo, plans to use the vaccine from China’s Sinovac in what the governor hopes will be a mandatory vaccination push.

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The developers of Russia’s Sputnik V vaccine will share science with Anglo-Swedish pharmaceutical giant AstraZeneca to explore possible advances against the coronavirus, both sides announced Dec. 11.

Turkey expressed doubt about Russia’s offering, only to quickly walk back the criticism. Argentina announced it will start using Sputnik V this month.

The fast-moving decisions are all being made without complete and peer-reviewed data on clinical trials.

“It’s all tied to the results of Phase 3,” said Jennifer Huang Bouey, a researcher focused on China and global health at the Rand Corp. “We haven’t seen anything yet.”

From Bali to Brazil

China has made a bold bid to improve its scientific credentials and further its global reach by engaging in vaccine diplomacy, linking the pandemic fight with other efforts to expand its political and economic ties.

The country has five vaccine candidates in the final stages of trials, which have taken place in regions of strategic importance to Beijing. Testing is underway in more than a dozen countries, including Pakistan, Turkey, Egypt, Saudi Arabia, Indonesia and Brazil.

Mexico’s government said it hoped to finalize a contract with China’s CanSino for supplies of vaccine by the end of the month.

Beijing has faced questions from scientists and officials for rolling out the vaccines before clinical trials were complete. Sinopharm said in November that it had applied for final approval with Chinese regulators.

Sinovac’s vaccine has been politically divisive in countries such as Brazil, with São Paulo’s governor, João Doria, throwing his support behind it and calling it the safest among the options. Brazil’s president, Jair Bolsonaro, a coronavirus skeptic and frequent China critic, opposes his plans.

A state governor said this week that Brazil plans to purchase 46 million doses of Sinovac’s vaccine, according to Reuters.

China’s decision to hold Phase 3 trials around the world has helped build trust in the vaccines, with foreign governments able to oversee and observe the trials themselves.

These on-the-ground trials in other countries have been particularly helpful given the checkered history of China’s vaccine industry. Between the two front-runners, Sinopharm has had vaccine quality scandals in the past, while Sinovac’s CEO has admitted in court to bribing China’s drug regulator over previous products before the pandemic.

Despite corruption and quality scandals, China’s vaccine industry has developed technical proficiency over the years, in part through technology transfers from foreign firms and scientists who return to China after work and studies overseas.

The experience of the SARS pandemic from 2002 to 2004 — concentrated in China — also spurred an urgency for vaccine preparedness within the country.

A 'mistake' to dismiss them

“Some skepticism about Russian and Chinese vaccines may be warranted, but to automatically dismiss these vaccines as ineffective or unsafe would be a mistake,” said Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine.

“These countries have many very good scientists, including expertise on vaccines and immunology.”

He also noted that China helped kick off the unprecedented global vaccine effort by publishing “the relevant gene sequence” early in the pandemic.

Evans said the big unknown is what the trials look like. “We do not know that they are weak,” he said. But skepticism is fueled by “a lack of knowledge about the processes and monitoring.”

Shipments of Sinovac’s vaccine have already arrived in Brazil and Indonesia, putting pressure on the nations’ regulators to approve its use.

AstraZeneca and Russia’s Sputnik V lab to share data

In a boost for Russia, AstraZeneca on Dec. 11 said it would soon begin work with the Gamaleya National Center of Epidemiology and Microbiology, the developers of the Sputnik V vaccine, to explore combining components of both vaccines that are based on the common cold virus.

Sputnik V’s developers also have offered to share the Russian vaccine with France’s Sanofi and Britain’s GSK. The offer came when Sanofi and GSK announced that their vaccine would be delayed until the end of next year because results of the Phase 1/2 trial found a low immune response in older adults.

According to the latest update by the Russian Direct Investment Fund, Sputnik V’s efficacy at preventing infection is 91.4 percent and those who contract the coronavirus after receiving the vaccine would not get a “severe case.”

So far, 20,000 people have received both doses of the vaccine in Phase 3 trials.

Denis Logunov, the deputy director of the Gamaleya center, which developed the Sputnik V vaccine, said there were ethical questions about continuing to enroll people in ongoing trials and giving 25 percent the placebo when there was an effective vaccine available. Talks with the Health Ministry and others were underway on the future of the trials.

Russian officials were taken aback last week when Turkey publicly spurned it. Turkish Health Minister Fahrettin Koca told Haberturk news that Turkey had abandoned plans to take the vaccine and went further, casting doubts on Russia’s scientific methods.

Koca reversed himself the same day, calling a news conference to say that Turkey has “no problem in procuring the vaccine produced in Russia” if tests are “successful.” He gave no timetable.

Russian Prime Minister Mikhail Mishustin said last week he expected “explosive demand” overseas.

Bar-Zeev noted that if countries want to mass distribute vaccines overseas, they will probably eventually seek to “prequalify” through the World Health Organization, which could ease some doubts about safety and efficacy.

“It will get reviewed as all products get reviewed,” he said, “and will need to pass that bar before WHO would support its widespread use.”

Rauhala reported from Washington, Dou from Seoul and Dixon from Moscow.

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