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Clinical human trials begin for COVID-19 vaccine in China

Brazil to acquire 100 mln Chinese CoronaVac vaccines: Health Minister
Source: Xinhua| 2021-01-08 10:19:17|Editor: huaxia

BRASILIA, Jan. 7 (Xinhua) -- Brazil has signed an agreement with the Butantan Institute of Sao Paulo to purchase 100 million doses of CoronaVac COVID-19 vaccines, developed by Chinese company Sinovac, Brazilian Health Minister Eduardo Pazuello said on Thursday.

A total of 46 million doses will be delivered in April and another 54 million doses by the end of the year, Pazuello said during a press conference.

All vaccines from the Butantan Institute will be incorporated into the national immunization plan, and will be fairly distributed throughout the country, the minister said.

The purchase of the CoronaVac vaccine was made possible on the basis of a decree announced by President Jair Bolsonaro on Wednesday, which allows the federal government to purchase COVID-19 vaccines in advance without the approval of the Brazilian National Health Surveillance Agency, Pazuello said.

On Thursday, the country reported a record daily count of 87,843 COVID-19 cases with 1,524 more deaths.
 
Coronavirus: WHO chief Tedros Adhanom Ghebreyesus tells rich countries to stop cutting the coronavirus vaccines queue
  • Ghebreyesus called on countries who have ordered excess doses to immediately hand them over to the Covax vaccine-sharing facility
  • The scramble for shots has accelerated as governments struggle to tame more infectious variants identified in Britain and South Africa


 
People's Daily, China @PDChina
China state-affiliated media

#Thailand is expected to buy two million doses of #COVID19 #vaccine developed by China's pharmaceutical company Sinovac Biotech, the World Health Organization (WHO) in Thailand said Sunday.

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3:00 AM · Jan 4, 2021
Global Times @globaltimesnews
China state-affiliated media

#Ukraine has signed an agreement to buy 1.8 million doses of China's Sinovac #COVID19 #vaccine which are expected to arrive in the country soon, the presidential office said on Wed.

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10:40 PM · Dec 30, 2020
 
Sinovac releases vaccine data in Brazil: 100% effective in preventing severe cases, could reduce hospitalizations by 80%
By Global TimesPublished: Jan 13, 2021 01:03 AM

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Quality inspectors on Sinovac vaccine production lines use digital technology platforms to monitor the quality and efficiency of vaccine packaging on Sunday. Photos: Li Hao/GT

Sinovac's COVID-19 vaccine is 100 percent effective in preventing severe and moderate infections, 77.96 percent effective in preventing mild cases, and has an overall efficacy of 50.4 percent in Brazil's final-stage trials.

Experts say the result is good enough considering almost all participants in Brazil are high-risk medical workers, and the 77.96 efficacy for mild-case protection means the vaccine can reduce 78 percent of people from needing hospitalization.

We have today one of the best vaccines in the world, Dimas Covas, director of the Butantan Institute in Brazil, said during a news conference on Tuesday.

Almost all of participants in the trials are medical workers at high risk of contracting the coronavirus. "The vaccine was able to 100 percent prevent severe illness in such a high-risk population, and effectively control the morbidity, and protect at least 50% of people from infection, which is good enough," Wang Guiqiang, director of the Infectious Disease Department at Peking University First Hospital, told the Global Times on Tuesday.

"Currently, the manufacturer requires a 0-14 vaccination doses program (Day 1 for first dose, Day 14 for second dose), but this probably cannot bring the highest level of antibody which then partly lowered the efficacy result. That's why some manufactures ask for a 0-21 vaccination program. But overall, its protective effects in such high-risk population is good enough," Wang stressed.

The manufacturer of the vaccine, named CoronaVac, requires recipients receive two doses 14 days apart, and if this was not adhered to, the efficacy could have been higher, Wang said.

The most frequent systemic effects were headache and myalgia and those events were mild and did not interfere with the participants' daily routine. There were no severe events associated with the vaccine.

Adverse events were very rare, Dimas Covas, director of the Butantan Institute, which cooperates with Sinovac on the trials in Brazil, said during a news conference on Tuesday.

Covas said it predicts that higher effectiveness will be seen in community use, and that it expects the vaccine will have a very high effectiveness among the general population similar to trials in other countries.

We chose the broadest number of symptoms. We would like to capture even the most simple symptoms. Those symptoms have not been included in similar studies, he said.

A 77.96 efficacy rate for mild-case protection means the vaccine can reduce 78 percent of people from needing hospitalization, effectively avoiding medical system collapse, Wang said.

Sinovac's vaccine has been undergoing Phase III clinical trials in Brazil, Indonesia and Turkey, which have designed different clinical plans based on their own domestic conditions, reads a document the Global Times obtained from Sinovac.

The plans, using vaccines from the same batch and the same immunization schedules, achieved different results of efficacy: 91.3 percent in Turkey; 100 percent protection against severe symptoms and 78 percent for mild cases in Brazil; and 65.3 percent in Turkey, which is normal and shows objectivity of clinical trials, according to the document.

Despite the difference in efficacy, the general conclusion is that the vaccine is protective, especially in preventing people from getting medium and severe symptoms, noted the Sinovac document.

For example, seven people who were hospitalized or critical cases in Brazil were all in the placebo group, which means the vaccine's protection rate for severe cases is 100 percent.

Meanwhile, in Turkey, the six hospitalized cases were also all in the placebo group, also showing a 100 percent protection rate for these cases.

These results demonstrate that the Sinovac vaccine would not lead to antibody-dependent enhancement which could bring about the failure of vaccines and infections that are even more serious.

Volunteers for Sinovac's vaccine in Brazil are all medical workers who are at the highest risk of infection. It is also the world's first Phase III clinical trials conducted among only medical workers, reads the Sinovac document.

The trials in Brazil also recorded the biggest ratio of slight symptom cases - 85 percent - as the team used highly sensitive Polymerase Chain Reaction (PCR) test.

There were also 1,394 volunteers who received two doses three weeks apart instead of two weeks apart. Efficacy among the former group is about 20 percent higher than the latter group, which means the overall efficacy could improve if all volunteers follow a 21 day schedule for second doses, Shao Yiming, one of the vaccine developers and AIDS expert at the China's CDC, told the Global Times on Tuesday.

Medical workers are in a high exposure population, which would decrease vaccine's protection efficacy, Shao noted, citing an example of previous international Phase III clinical trials on an AIDS vaccine.

The trials show that the vaccine's efficacy is 30 percent in Thailand but 0 percent in South Africa while AIDS incidence rate in South Africa is four times that of Thailand.

The more a vaccine is attacked by the virus, the lower its efficacy would be, which could explain the comparatively low efficacy of COVID-19 vaccines in medical workers, Shao explained.

Recently, AstraZeneca released detailed data on its vaccine which shows it has a 70 percent efficacy for people showing symptoms and 27 percent efficacy for silent virus carriers.

Meanwhile, the incidence rates in placebo groups of Pfizer and Moderna's Phase III clinical trials were 7.29 percent and 3.34 percent respectively, which were lower than the US' overall incidence rate during the same period. The phenomenon is abnormal under a high-sensitivity supervision system in clinical trials, according to Shao.

It is notable that the infection risk of Sinovac's trial environment is three times higher than Pfizer's and six times higher than Moderna's, Shao stressed. He said that the protection rate of a vaccine not only depends on its efficacy but also its environment of infection risk. He thought that Sinovac's vaccine would show better protection rate in the public.

The exceedingly high-sensitive system Sinovac used would drag down efficacy, Shao said.

CoronaVac's clinical trials on children and pregnant women will be conducted soon, according to Brazilian official.
 
WHO team working with Chinese vaccine producers ahead of potential emergency use: WHO director-general
Source: Xinhua| 2021-01-13 12:42:20|Editor: huaxia

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Photo taken on Jan. 6, 2021 shows COVID-19 vaccines at a packaging plant of Sinovac Research and Development Co., Ltd. in Beijing, capital of China. (Xinhua/Zhang Yuwei)

WHO continues to ask vaccine manufacturers from around the world to move swiftly to provide necessary data that will allow the organization to consider them for emergency use listings, Tedros said.

GENEVA, Jan. 13 (Xinhua) -- The World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus has said that a WHO team in China is working with producers of the Sinovac and Sinopharm vaccines for potential emergency use listings.

"I'm pleased that a WHO team is in China currently working with producers of the Sinovac and Sinopharm vaccines to assess compliance with international quality manufacturing practices ahead of potential emergency use listing by WHO," Tedros said at a recent media briefing.

He noted that WHO continues to ask vaccine manufacturers from around the world to move swiftly to provide necessary data that will allow the organization to consider them for emergency use listings.

"While we are hopeful about the safe and effective vaccines that are being rolled out, we want to see this sped up and vaccines allocated equitably in the coming weeks," Tedros said.
 
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