A few weeks ago we wrote about how scientists around the globe are working to bring a COVID-19 vaccine to market. With infection rates increasing in many countries and some seeing a resurgence after weeks without new cases, a vaccine is our best chance of beating the coronavirus and getting back to normal.
Each day, we seemingly come closer to a vaccine becoming a reality. In today’s post, we’ll look at the progress to date and discuss when we’re likely to see a vaccine being rolled out.
How do Scientists Develop Vaccines?
Vaccines must adhere to higher safety standards than other drugs because they are given to millions of healthy people. Usually, it takes years for a new drug to be approved for use. However, due to the severity of the COVID-19 pandemic, scientists are working to have a vaccine available in just 12-18 months.
Here’s what has to happen with a drug for it to be approved for use in the general population:
Before a new drug can be tested in humans, it’s first given to animals. This stage is used to determine whether it triggers the immune response that scientists are hoping to achieve.
If the drug shows potential in pre-clinical tests, it’s then given to a small group of people. This stage is used to test its safety and to discover more about the immune response it delivers.
The medicine is given to hundreds of people to learn more about its safety. Phase 2 is also used to find the correct dosage of the drug.
Next, the vaccine is given to thousands of people to check for rare side-effects or adverse reactions. Phase 3 also uses a placebo, a substance that has no therapeutic effect, which is given to a control group to measure the effectiveness of the new drug.
140 Vaccine Candidates
Vaccines work by mimicking the virus that they are designed to protect against. This stimulates our immune system to develop antibodies that can fight the virus if we come into contact with it.
At the time of writing, the World Health Organization (WHO) is tracking more than 140 candidate vaccines. These candidates are at the following stages:
- Pre-clinical: 142
- Phase 1: 17
- Phase 2: 13
- Phase 3: 5
- Approved: 0
Although there are some promising candidates in development, the WHO has warned that “there is no silver bullet at the moment.” As such, the only chance we have of stopping outbreaks right now is for governments to test, isolate, and treat patients, and for the public to practice good hygiene, stick to social distancing recommendations, and wear a face mask in public places.
Which Vaccine Candidates are Most Promising?
The race is on to be the first to bring a vaccine to market, and several labs are nearing the finish line. These are some of the candidates that are fighting to be first.
Sinovac is a Chinese company working to develop a vaccine based on inactivated COVID-19 particles. Testing shows that the vaccine has a promising safety profile and stage 3 trials are in progress in Brazil.
Wuhan Institute of Biological Products/Sinopharm
This vaccine was the first to enter phase three clinical trials, which have been underway in the United Arab Emirates since late-June. The vaccine candidate did not show any severe adverse side effects in the first stages of clinical trials and so far it looks to be safe, which is extremely promising.
University of Oxford/AstraZeneca
Scientists at the prestigious UK university has developed a vaccine delivered via a vaccine vector, which uses a chemically weakened virus to make the immune system respond accordingly. The vector contains genetic code from the coronavirus and preliminary results from the University of Oxford vaccine show that it generates a strong immune response.
US biotech company Moderna is using a technique that tricks the body into producing viral proteins itself. This type of vaccine has never been approved for use against infectious disease, but it has the benefit of potentially being faster to develop and easier to produce than traditional vaccines.
Will US Citizens be Vaccinated?
Despite many of us around the globe waiting anxiously for a vaccine, research shows that as many as 50% of people in the US do not plan to be vaccinated. Anti-vaccine activists have been vocal online since the pandemic began, with many taking to Twitter to argue that COVID-19 is a scam with the aim of companies profiting from an eventual vaccine. And, as the crisis has grown over the past several months, the mistrust in vaccines has grown.
The Centers for Disease Control and Prevention (CDC) is currently working on a plan to build “vaccine confidence” as labs continue to develop possible candidates. Only time will tell whether it will be successful in its mission.