Researchers from around the world are competing to develop a Covid-19 vaccine, with more than 140 candidate vaccines now tracked by the World Health Organization (WHO).
Vaccines typically require years of testing and additional time to produce at scale, but scientists hope to develop a coronavirus vaccine within 12 to 18 months.
Vaccines mimic the virus, or part of the virus, that protect and stimulate the immune system to develop antibodies. They must follow higher safety standards than other medications because they are administered to millions of healthy people.
How are vaccines tested?
At preclinical stage In tests, researchers administer the vaccine to the animals to see if it triggers an immune response.
In phase 1 In clinical trials, the vaccine is given to a small group of people to determine if it is safe and to learn more about the immune response it causes.
In Phase 2The vaccine is administered to hundreds of people so that scientists can learn more about its safety and the correct dosage.
In phase 3, the vaccine is administered to thousands of people to confirm its safety, including rare side effects, and its effectiveness. These trials involve a control group receiving a placebo.
Vaccines in clinical trials.
Phase in progress
Phase completed
Oxford University / AstraZeneca
The Oxford University vaccine is administered through a chimpanzee virus, called a vaccine vector. The vector contains the genetic code for the protein spikes found in the coronavirus and triggers a strong immune response in the human body. The vaccine is in a phase 2/3 combination trial in the UK and has recently entered phase 3 trials in South Africa and Brazil.
CanSino Biologics Inc./Biking Institute of Biotechnology
The vaccine developed by the Chinese company CanSino Biologics and the Beijing Biotechnology Institute, a university close to the Chinese military, reportedly showed promising results in phase 2 trials, although no data from the trial has been released. In a world first, the vaccine has now been approved for military use, but it is unclear how widely it will be distributed.
US biotech company Moderna is developing a candidate vaccine using messenger RNA (or mRNA for short) to trick the body into making viral proteins. No mRNA vaccine has been approved for an infectious disease, and Moderna has never brought a product to the market. But proponents of the vaccine say it may be easier to mass-produce than traditional vaccines.
Wuhan Biological Products Institute / Sinopharm
Beijing Biological Products Institute / Sinopharm
BioNTech / Fosun Pharma / Pfizer
Institute of Medical Biology, Chinese Academy of Medical Sciences
Gamaleya Research Institute
Clover Biopharmaceuticals Inc./GSK/Dynavax
Anhui Zhifei Longcom Biopharmaceutical / Institute of Microbiology, Chinese Academy of Sciences
Academy of Military Sciences of the People’s Liberation Army (PLA) / Walvax Biotech.
University of Melbourne / Murdoch Children’s Research Institute
The Murdoch Children’s Research Institute in Australia is conducting a phase 3 trial with a nearly 100-year-old tuberculosis vaccine. The vaccine is not believed to directly protect against Covid-19, but could increase the body’s nonspecific immune response.
Source: WHO. Last update July 2
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