How are Chinese Sinovac and Sinopharm Covid vaccines?
China appears to have made two frontier vaccines from two front runners , Sinovac and Sinopharm . What do we know about these firms?
The Beijing-based biopharmaceutical company Sinovac is behind the CoronaVac, an inactivated vaccine. It use killed viral particles to expose the body’s immune system , like old style vaccine such as rabies vaccine , to stimulate the immune without risking a serious disease.
Which , by comparison , the Pfizer and Moderna vaccines being developed by mRNA virus , means that the virus’s genetic part is injected into the body , triggering the body to begin making viral proteins, but not the whole virus , which enough to train the immune system to attack.
The firm said that “”mRNA vaccines are a new type of vaccine and there is [currently] no successful example [of them] being used in the population,”
On paper , one of The Sinovac’s main advantages is that it can be stored in a standard refigerator at 2-8 C , like the vaccine from Oxford , which is made from genetically engineered common cold virus. The other two , Moderna’s vaccine needs -20 C and Pfizer’s vaccine at whopper -70 C .
How effective is it? It’s hard to tell right now.
A Chinese study published in the scientific journal The Lancet only has information from the first and second phase trials of CoronaVac in China. Zhu Fengcai, one of the authors of the article, said those results – based on 144 participants in the phase one trial and 600 in the phase two trial – meant that the vaccine was “suitable for emergency use.” CoronaVac has undergone phase three trials in several countries. Interim data from late-stage trials in Turkey and Indonesia showed that the vaccine was 91.25% and 65.3% effective, respectively.
Researchers in Brazil initially said it was 78% effective in their clinical trials, but in January 2021 they revised that figure to 50.4% after including more data in their calculations.
In early November, this trials were briefly stopped after the death of a volunteer, but resumed after death was not found to have no link to the vaccine. Sinovac has been approved for emergency use in high-risk groups in China since July. In September, Mr. Yin from Sinovac said the tests were conducted on more than 1,000 volunteers, of whom “some showed only minor fatigue or discomfort ,no more than 5%.”
And the Sinopharm vaccine?
Sinopharm, a Chinese state-owned company, is developing two Covid-19 vaccines, which, like Sinovac, are also inactivated vaccines that work in a similar way.
Sinopharm announced on December 30 that trials of the third phase of the vaccine showed it to be 79% effective, lower than that of Pfizer and Moderna. However, the United Arab Emirates, which approved a synopharmaceutical vaccine earlier this month, said the vaccine was 86% effective, based on interim results from its phase three trial.
A company spokeswoman declined to explain the discrepancy, saying detailed results would be released later, a Reuters report said. But even before the results of the third phase trials, the vaccine had already been distributed to nearly a million people in China as part of an emergency program.
Professor Dale Fisher of the National University of Singapore said at the time that it was “unconventional” to step up a vaccine program without going through late-stage trials first. “It is normal to wait for an analysis of the third phase trials before intensifying a vaccine program by authorizing emergency use,” he told the CNBC news site.
In early December, Peru suspended trials for the synopharm vaccine due to a “serious adverse event” that affected a volunteer. It later said it lifted the suspension. A pause in a clinical trial is not unusual. In September, the UK halted trials for another Covid-19 vaccine after a participant had a suspected adverse reaction, resuming after the vaccine was ruled out as the cause.
The spread of the coronavirus within China has for the most part been contained – and life is slowly but surely returning to a “new normal.”
Any other vaccine candidates?
At least two other Covid-19 vaccines are in development in China, according to a recent article in The Conversation. One of them is CanSino Biologics, which is reported in phase three clinical trials in countries including Saudi Arabia. The other is being developed by Anhui Zhifei Longcom. Its vaccine uses a purified piece of the virus to trigger an immune response, and it has recently entered phase three testing, according to the report
