#COVID19: 5 promising vaccine candidates currently in trial
With nearly 2.5 lakh deaths and over 35 lakh infections, COVID-19 has transformed from a mysterious pneumonia-like disease to the worst public health crisis of our time. The disease has swept across more than 170 countries, keeping people desperately waiting for some sort of cure or vaccine. But, the real question is: Where exactly are we with these efforts? Let's find out.
WHO has confirmed that at least 76 vaccine candidates have been developed to train the human immune system into recognizing the novel coronavirus (SARS-CoV-2) that causes COVID-19 and fight it off upon detection. However, out of all those efforts, only a handful have gone into the clinical trial phase, which involves administering the vaccine on humans and determining its efficacy and safety.
CanSino is testing Ad5-nCoV as a viral vector vaccine that uses a modified version of the common adenovirus, with coronavirus-like spike proteins, to generate an immune response. It teaches the body to detect the spikes and prevent the novel coronavirus from using them to latch on to cells. Ad5-nCoV is considered a front-runner by experts but there are concerns over fever being a side-effect.
US-based biotech firm Moderna Therapeutics has developed an mRNA vaccine that uses parts of the coronavirus' genetic material to generate an immune response from the body. The Phase I human trial of the vaccine is currently underway, with Phase II and III planned for later this year. Moderna has also partnered with Swiss firm Lonza Group AG to produce a billion vaccine doses.
Pennsylvania-based Inovio Pharmaceuticals has developed a DNA-based vaccine that delivers genetic material of the virus into the cells and increases the production of the antibodies known to fight it. The vaccine went into Phase I in April and is expected to go into Phase II in the coming months. Inovio is hoping to have a million doses of the vaccine before the year ends.
This particular vaccine, currently being tested on hundreds in a large Phase I trial, is one of the most promising candidates as it is expected to hit the markets by September-October, assuming all goes according to the plan. It uses a modified adenovirus to deliver the coronavirus' genetic material into the body and prime the immune system to fight off the COVID-19 infection.
China's Sinovac Biotech has developed a vaccine that uses an inactive SARS-CoV-2 to generate an immune response against the active version of the virus. It is being tested on 144 people as part of a Phase I trial and is likely to be tested on 744 individuals in Phase II. Animal tests suggest it could provide 'complete protection' but human results are still awaited.
While these vaccines are promising, we are going to see more experimental candidates move from pre-clinical to clinical trials in the near future. If all goes well, we may have a vaccine before the year ends, but there is a chance that the process might be delayed. On an average, companies estimate, fast-tracked vaccine development and production may take about 12-18 months.