Russia is also trying to play a role in developing countries or countries such as India with  large populations, parts of which have inadequate access to healthcare.

The Chinese government, which claims that millions of emergency use doses – the figures vary – have been administered, touts the country’s ample capacity to manufacture large volumes relatively quickly at lower costs than US or European rivals.

Many in the West are skeptical about the Chinese numbers, saying that the manufacturers have shared scant data about their ongoing Phase 3 clinical trials or the emergency-use inoculations carried out. Confusion about the accuracy of efficacy figures has also done little to build trust.

Up to seven candidates in Phase 3 trials

China is considered to have five to seven candidates in Phase 3 clinical trials currently, and Beijing is known to grant conditional approvals even if the manufacturers have not yet completed the clinical trials, if needed to cope with public health emergencies at home or abroad. Drugmakers must still submit final results after they receive conditional approval.

Several Chinese companies are developing Covid vaccines, and state-owned Sinopharm Biotech’s candidate has received conditional approval (similar to the approval procedure practiced in the EU) from the Beijing government, while privately owned Sinovac has received emergency use authorization, analog to the approvals in the US and UK so far. 

Other Chinese manufacturers with Covid vaccine candidates under development include CanSino Biologics, which is working closely with the country’s military, along with another state-run manufacturer, China National Biotech Group (CNBG).

CanSino, whose vaccine, like the AstraZeneca/Oxford and Johnson & Johnson candidates takes a viral vector approach, has been carrying out trials in Mexico and according to health officials there plans to submit interim results of Phase 3 to Mexican authorities soon. The vaccine was authorized for emergency use in the Chinese military in June 2020. The two CNBG shots are being tested in several countries, including the United Arab Emirates, Egypt, Peru and Argentina.

By its own account, the People’s Republic aims to inoculate 50 million people with domestic Covid-19 vaccines ahead of the Lunar New Year celebrations that begin on Feb. 11, with the Sinopharm candidate being offered free to Chinese citizens.

Most of the clinical trials are being carried out in other countries, as China has too few people that have not been in contact with the virus. Indonesia and Bahrein were among the first countries to approve a Chinese vaccine, and Turkey has authorized emergency use. Trials are reportedly in progress in Russia, Egypt and Mexico.

While regulatory authorities in Beijing reported no severe side effects for Sinopharm’s candidate, its rollout was accompanied by a drum roll naming multiple side effects, not unexpectedly from Taiwan.
 

Efficacy estimates diverge widely

Sinopharm claims 79% efficacy for its vaccine, which Chinese officials said is already in mass production, even though the company has not provided details on how the trial results were determined, including how many participants received a placebo or vaccine. Detailed data will be released later, Sinopharm has promised.

Both of the latter two Chinese shots are traditional type vaccines, using an inactivated version of the SARS-CoV-02 virus to spark an immune response to expose the body's immune system to the virus without risking a serious disease response.

Due not least to the lack of Phase 3 data, the present discussion of the Chinese shots revolves around efficacy. Turkish researchers said the Sinovac product was 91.25% effective, while Indonesia, which started mass vaccinations in January, said it was 65.3% effective, based on a trial with 1,600 participants.  Both interim results were from late-stage trials.

The most heated discussion is raging in Brazil, one of the countries worst affected by Covid-19 and where the government’s response is widely seen as chaotic. While Sinovac initially reported an efficacy figure of 78% in the Brazilian trial with 12,000 healthcare workers, the local Butantan Institute, which conducted the trials, subsequently said it was just 50.4%, barely meeting the World Health Organization’s minimum threshold of 50%.

The institute asserted that the vaccine had been shown to provide 100% protection against severe cases of the disease but later acknowledged that this was based on a group of seven volunteers who had become seriously ill in the placebo group, a sample size too small to have any statistical significance. Reuters reported last month that Brazil’s federal government plans to purchase 46 million doses of the CoronaVac vaccine in any case.

Sinovac chairman Yin Weidong said the results of trials with its candidate in Turkey, Indonesia and Brazil prove it is sufficiently safe and effective, stressing that the most important factor in Brazil was the 100% efficacy rate against serious cases of Covid-19 as reported by Butantan. Yin said the company would analyze and review the data before seeking approval for conditional use in China.

The CoronaVac maker claims to have built up enough capacity by now to produce 500 million doses and said that by February it could double output to 1 billion doses annually. The Chines company said it has received orders far exceeding that amount, in particular from Indonesia, Turkey, Malaysia, Singapore and the Philippines.

Pakistan’s minister for science and technology, Chaudhry Fawad Hussain, said on Twitter that his country would buy 1.2 million doses of the Sinopharm vaccine in this year’s first quarter.

Those monitoring the global vaccine discussion have attempted to reconcile the various discussion points. Penny Lukito, head of Indonesia’s National Agency of Drug and Food Control, said differences in efficacy were not the primary base of vaccine access in Indonesia. Other important factors included finding vaccines that can be easily and safely distributed.

An Indonesian epidemiologist at Griffith University in Australia told BBC News that the Sinovac vaccine could be very useful for his country because it was likely to be cheap and didn’t need to be stored at extreme temperature.

In contrast, Jerome Kim, director of the International Vaccine Institute in Seoul, Korea, told the newspaper Wall Street Journal that without more details and an explanation from the company, it was not yet possible to judge whether countries should be using CoronaVac. The way the vaccine has been rolled out “reduces confidence,” he said.

Author: Dede Williams, Freelance Journalist