The race is on to find a COVID-19 vaccine to stop the spread of the COVID-19 virus. Countries around the world are using different vaccine technologies to try and find ones that can halt the pandemic. There are more than 102 candidate vaccines that researchers are working on, eight of which are now being tested in clinical trials in humans.

How long does it take to develop a vaccine

It is important to note that a vaccine fit for humans usually takes years to develop as it goes through a series of human trials to test its safety and efficiency. The World Health Organization is tracking the potential vaccines for COVID-19 in the clinical evaluation

Here’s taking a look at the four potential vaccines which are leading the race:

Oxford University vaccine

One of the potential vaccines against COVID-19 is also known as ChAdOx1 nCoV-19. It was developed by the Jenner Institute and Oxford Vaccine Group, at the University of Oxford.

The vaccine candidate uses a weakened strain of common cold virus (adenovirus) and is combined with the genetic material of the SARS-CoV-2 (the coronavirus causing COVID-19).

This will enable the body to identify the spike protein of the novel coronavirus. The vaccine candidate is now in a clinical trial phase-1 and healthy volunteers have already been injected to check its safety and efficiency.

Beijing-based Sinovac Biotech

The Chinese biopharmaceutical company is also doing phase-1 and phase-2 trials of its COVID-19 vaccine. The company said it is also in discussion with regulators in other countries, and the World Health Organization (WHO), to launch phase-3 clinical trials in regions where the novel coronavirus is still spreading rapidly.

Sinovac is also ahead in the race, as it was previously developing a vaccine against SARS, the 2003 pandemic that also originated in China and is caused by a type of coronavirus. The company had to abandon the development at the phase-1 stage as that outbreak was contained.

​Pfizer and BioNtech vaccine

US-based Pfizer pharmaceutical company and its German partner BioNtech are working together on four RNA vaccine candidates. They also began clinical trials of their vaccine candidate BNT162. Their vaccine candidate is based on specially designed messenger RNA (similar to the Moderna vaccine) and the trails for testing the vaccine are taking place in the USA and they plan to test the potential vaccine on 360 healthy volunteers.

Massachusetts-based Moderna vaccine

In the US, the Massachusetts-based biotech company Moderna is developing an RNA based vaccine in collaboration with the National Institute of Allergy and Infectious Diseases (NIAID). The vaccine candidate mRNA-1273 has already conducted phase 1 trials and is all set to begin phase 2 trials. The RNA vaccine works by entering the human cells and carries the molecular instructions to make the viral protein. Once, this viral protein is recognized by the body, the immune system of the body is triggered.