70 vaccines in development globally for COVID-19, human trials progressEuropost
There are 70 coronavirus vaccines in development globally included three already being tested in human trials, according to the World Health Organisation, and even more research teams will reach that stage within weeks. In the past week, the international agency released a “draft landscape of COVID-19 candidate vaccines”.
The furthest along – in phase two – is the “adenovirus type five vector” candidate vaccine developed by the Academy of Military Sciences and biotech firm CanSino in China’s capital of Beijing. The clinical trial was given the green light in March, shortly after US drug developer Moderna said it had begun human tests for their vaccine with the US National Institutes of Health, jabbing 45 healthy volunteers in Seattle.
“This vaccine incorporates the spike protein which is the protein that is on the surface of the virus,” NIH lead scientist Dr Kizzmekia Corbett told CNN this week. “That protein is the reason, essentially, why the virus is able to attach to a cell and then get into a cell and cause an infection. So from our perspective, if we can incorporate that protein into our vaccine, and essentially allow the body to create a response to that protein that may block an infection later, we’ve created a successful vaccine.” Their “rapid response” was multi-layered, Dr Corbett said.
She said they received the sequence online from the Chinese Government “at the same time as the rest of the world” but given their previous research into coronavirus vaccine development and prior agreed collaboration with Moderna on other testing, they were able to push for the vaccine to “get into a human trial in 66 days”. Dr Corbett said their plan “is to have people vaccinated all over the world by next Spring (March to May 2021)”.
The third candidate vaccine to be at the human trial stage is by fellow US drugmaker Invio Pharmaceuticals. One of the 67 others in preclinical evaluation is at the University of Queensland, in collaboration with biopharmaceutical company Dynavax as a Coalition for Epidemic Preparedness Innovations (CEPI) initiative.
“We are proud to contribute to this global effort to develop a vaccine to prevent COVID-19 in collaboration with the exceptional team of researchers at the University of Queensland,” Dynavax chief executive Ryan Spencer said in a statement.
Pre-clinical trials are also in progress at labs across the globe including Japan, Germany, Sweden, India, Belgium, Spain and Russia.
One of those being developed, at Oxford University’s Jenner Institute in the UK, is set to graduate in the next fortnight to a human trial designed to enrol up to 510 participants aged 18 to 55.
Vaccinology Professor Sarah Gilbert on Saturday told The Times she was “80 per cent confident” it would work.
“We had recently started thinking about an appropriate response to Disease X; how could we mobilise and focus our resources to go more quickly than we had ever gone before,” Prof Gilbert said in peer-reviewed medical journal The Lancet. “And then Disease X arrived.”
She said the “best-case scenario” is that by autumn in the UK, September to November 2020, “we have an efficacy result from phase three and the ability to manufacture large amounts of the vaccine”.
“But these best-case time frames are highly ambitious and subject to change,” Prof Gilbert said. “Our ability to determine vaccine efficacy will be affected by the amount of virus transmission in the local population over the summer (June to August), and we are also beginning to think about initiating trials with partners in other countries to increase our ability to determine vaccine efficacy.”
A team at the University of Pittsburgh School of Medicine in the United States said they were able to move quickly in developing a potential COVID-19 vaccine after working on other coronaviruses that cause Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS).
When tested in mice, the prototype vaccine - which the researchers have called PittCoVacc - generated what they described as “a surge of antibodies” against the new coronavirus within two weeks.
The Pittsburgh researchers cautioned that because the animals have not been tracked for very long as yet, it is too early to say whether and for how long the immune response against COVID-19 lasts. But they said that in comparable tests in mice with their MERS experimental vaccine, a sufficient level of antibodies was produced to neutralise the virus for at least a year.
In addition to the 70 listed by the WHO, China has approved early-stage human tests for two experimental vaccines, state media Xinhua reported on Tuesday.
The vaccines are being developed by a Beijing-based unit of Nasdaq-listed Sinovac Biotech, and by the Wuhan Institute of Biological Products, an affiliate of state-owned China National Pharmaceutical Group.
Professor Ian Frazer from the University of Queensland, who was involved in developing the vaccine for HPV which causes cervical cancer, said one challenge of developing a vaccine for the coronavirus is that it infects the upper respiratory tract.
“It’s a separate immune system, if you like, which isn’t easily accessible by vaccine technology,” he told ABC’s Health Report. "I think it would be fair to say even if we get something which looked quite encouraging in animals, the safety trials in humans will have to be fairly extensive before we would think about vaccinating a group of people who have not yet been exposed to the virus.
"They might hope to get protection but certainly wouldn't be keen to accept a possibility of really serious side effects if they actually caught the virus."