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How are vaccines developed? What are the stages? - A guide to the stages of vaccine development

In the 21st century, the Covid-19 vaccine is definitely the most anticipated medical discovery. Research organizations and pharmaceutical companies across the globe are working on their own versions of the vaccine with the goal of eradicating the novel coronavirus. With us constantly monitoring the vaccine development process, learning about the various stages of development will help in gainingperspective into this scientific process.

The Process of Vaccine Development

Vaccine development is a long and complicated process that can take as long as 10-15 years.It consists of different stages and phases that involve thorough research and many tests before the final product is approved and manufactured at a massive scale. But with advanced technology, medical expertise, and quicker approvals, experts are of the opinion that it may take about 12-18 months before the Covid-19 vaccine is ready for the public.

Until then, it is important to take all possible precautions and also buyhealthinsuranceonline or through an agent for uncertain times. You can also take thecoronavirus health insurance policyboth for yourself and your loved ones. Corona Kavach health insurance not only ensures quality treatment, but also saves you from the unpredictable hospital bills.

Here is some information on how vaccines are developed by medical experts and researchers.

Different stages of vaccine development

The main stages of vaccine development are:

  • Exploratory Stage

  • Pre-clinical Stage

  • Clinical Development

  • Regulatory Review and Approval

  • Manufacturing Stage

1. Exploratory Stage: This is the first stage when scientists and medical experts conduct basic laboratory research. This may last for about 2-4 years. In this stage, the experts look for natural or scientific antigens that can help treat a disease or prevent it. The antigens may contain weakened bacteria or viruses, virus-like particles, and other substances obtained from pathogens.

Research is a slow and extensive process that requires many approvals, secure funding, and minute study of every result. However, now when the entire world is fighting the novel coronavirus pandemic, many countries around the world are trying to expedite the process and develop a vaccine at the earliest.

2. Pre-clinical Stage: In this stage, the developed vaccine is tested on animal subjects such as mice and monkeys to know if it has any positive cellular response on them. This also gives researchers an idea about the possible response the vaccine might have on humans. Based on the test results, researchers can also decide on the safe starting dose for the next phase of research and the best mode of administering them.

Researchers also try to make the vaccine more effective in this stage. Many times, they administer the vaccineto the subject animals and then infect them with the pathogen to check the results.

3. Clinical Development: This consists of 3 sub-phases. It is one of the most important stages as many promising potential vaccines often fail here.
Phase I trial: In this phase, a trial is performed on some 20-80 humans to assess if the vaccine is safe or not. It also gives researches an idea about the kind of immune response the vaccine has. The vaccinated participants are monitored carefully in this phase and the conditions are controlled. IfPhase I trial is successful, researchers progress to the next phase.
Phase II trial: In this phase, researchers test the candidate vaccine on several hundred individuals of different age groups. Some may even belong to groups that are at a higher risk of acquiring the disease. The test helps determine the vaccine’s safety and its effect on the immune system. In Phase II, scientists may also try to find out immunogenicity or the ability of an antigen to provoke an immune response in the body. They may determine the proposed doses, immunization schedules, and methods of delivery as well.
Phase III trial:
After the success ofPhase II candidate vaccine, researchers conduct trials on a larger scale and vaccinate thousands of people. They see how many unvaccinated people get infected compared to those who have been vaccinated. Researchers or scientists also look for any side effects of the vaccine.

4. Regulatory Review and Approval:
If Phase III trial is successful, the vaccine developer submits a Biologics License Application (BLA) to the FDA. Once the FDA grants approval, labelling of the vaccine is done. After granting the license, the FDA will continue to inspect the facilities, monitor vaccine production, and review the vaccines for safety, potency, and purity.
Phase IV trial:
This is done after the vaccine has been released. In this phase, the manufacturer continues to test the vaccine for its effectiveness and safety. They may also check if the vaccine has any other potential uses.

5. Manufacturing Stage:
The vaccine is manufactured in a mass scale following stringent quality control measures. It is then distributed to the most vulnerable sections of the society first. In case the vaccine has a negative effect on any candidate, it is sent back to the laboratory for further research.


Now when Covid-19 has already gripped the world, a vaccine is the best way to stop the spread.While scientists and medical experts in many countries are working on it diligently, all we can do is take the necessary precautions and stay safe. Also, make sure you have a coronavirus health insurance policy or Corona Kavach policythat covers the entire family. In case you or a loved one gets infected, this healthinsurance plan will ensure access to quality healthcare. Buy medical insurance online today and save yourself from hassles!

Disclaimer: The above information is for illustrative purpose only. For more details, please refer to policy wordings and prospectus before concluding the sales.

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