Human trial of Covid-19 Vaccine

 11/05/2021  COVID-19

Reassuring news is coming out of the labs from across the world as scientists work tirelessly to find that one magical potion which will bring the planet back on its feet – a vaccine for the marauding Corona Virus. Human trials for COVID-19 vaccines are under way, with Russia, the United Kingdom, the United States of America and India at the forefront of the ongoing vaccine research to fight an invisible enemy. In India, about a thousand volunteers are participating in the human clinical trials.

Meanwhile, the human trial of the vaccine produced by Oxford University is showing promising results whereas Russia has claimed its vaccine is ready. At home, The Drugs Controller-General of India (DCGI) has permitted development of two vaccines — one being worked out by Bharat Biotech International Limited in collaboration with the Indian Council of Medical Research and the other by Zydas Cadila Healthcare Ltd. They are in phase 1 and 2 of human trials. Around the world, more than 140 vaccines are at the preclinical stage, 27 have managed to be applied for human trials and one has been approved for military use in China, as reported by Financial Express on 22nd July.

Why Human Trial of Vaccine is needed before launching

Human clinical trial of vaccine is done to establish the safety and efficiency of a vaccine prior to it being licensed. One vaccine formulated to cure any pandemic disease like Covid-19 needs clinical trial. Earlier, low-dose vaccines or medications were used to be injected into animals like monkeys, rabbits and hamsters, but in special cases like Covid-19, human trial is mandatory before launching any vaccine. The simple reason for human trial is that Covid19 is said to be affecting only humans, and not animals. For clinical trial, a set of human volunteers are being chosen with different health conditions. Any vaccinal trial on the human body, after a certain period of time, will show the side-effects or reactions. It is, therefore, necessary to test the effects on humans who are perfectly healthy as well as on people having conditions like hyper-tension, high blood sugar, and heart diseases.

According to the renowned U.S.-based health protection agency Centers for Disease Control and Prevention, the general stages of development of a vaccine are:

  • Exploratory stage
  • Pre-clinical stage
  • Clinical development
  • Regulatory review and approval
  • Manufacturing
  • Quality control
  • A vaccine for Covid-19 goes through four stages of human trials.

    Phase One Trial: in this stage, the targeted group of volunteers is given injection, and data collected thereafter on antibody production, any outcome or side-effects or illness due to infection. This is done to estimate the efficacy of the particular vaccine.

    Phase Two Trial: the second stage is focused on the immunogenic and toxicity results from phase one healthy volunteers. This stage engages more healthy volunteers to determine the reactions in sets of human volunteers on different test schedules.

    Phase Three Trial: the stage involves the continuous focus on monitoring the toxicity and immunogenicity on a larger scale of testing.

    Phase Four Trial: this stage is about monitoring the previous stages that collect information continuously on vaccine usage, adverse effects, and long-term immunity.

    A vaccine must claim to be safe and effective in natural disease conditions before being submitted for approval and mass production. More than 140 vaccines have been produced but haven’t made it to human trial yet. A clinical human trial of a certain vaccine takes a total time of 12 to 18 months but due to this pandemic situation and the resultant human crisis, the trial time has been reduced. As per data available, we might expect a vaccine by December 2020. But then, we will have to keep in mind that this vaccine will only be available in government and private hospitals under supervision of experts.

    Whenever existence has been at stake, humanity has always come together as a unified entity to fight and defeat odds. It feels great to know that so many people have volunteered for Human trials, and it doesn’t matter where they all came from. We hope people realize that our strengths lie in being together. The day may not be too far when we can celebrate life once again by successfully defeating the pandemic but as we do so, we must this time return to nature what we have been taking from it mindlessly. Nothing is granted on planet Earth, as the pandemic has proved, not even our existence.