Haryana minister Anil Vij tested positive for COVID-19 two weeks after being given a shot of the Covaxin, developed by the Bharat Biotech, Hyderabad.
Bharat Biotech responding to Anil Vij contracting the coronavirus said, Covaxin’s efficacy can be determined only 14 days after the second dose. In the case of this vaccine, trial volunteers receive two intramuscular injections approximately 28 days apart.
Elaborating more on this, Bharat Biotech added the Phase-III trials are double-blinded and randomised, where 50 per cent of subjects will receive the vaccine and 50 per cent will receive placebo, and the investigators, the participants and the company are not aware of who is assigned to which group.
Meaning of placebo
Dictionary definition of placebo:
A medicine or procedure prescribed for the psychological benefit to the patient rather than for any physiological effect
A substance that has no therapeutic effect, used as a control in testing new drugs
What is a placebo?
A placebo is something that seems to be a "real" medical treatment, but it isn't. It could be a pill, a shot, or some other type of "fake" treatment. All placebos do not contain an active substance meant to affect health.
How are placebos used?
For example a new medication to alleviate diabetes may be offered to certain individuals in a study. Others may have been offered a placebo.
None of the individuals in the sample will know if the true medication or placebo has been offered. The effects of the medication and placebo on the individuals in the sample will then be compared by researchers.
That way, the efficacy of the new medication can be assessed and side effects reviewed.
Many volunteers at a vaccine trial get placebo
Many volunteers are given placebo during the phases of Covid-19 vaccine studies. Experts claim that if actual vaccines are given to all the volunteers, the side effects and long-term outcomes are not real.
Placebos randomly assigned
Placebos have been used for decades in clinical trials. Neither the volunteers nor the inoculation suppliers know who is given a placebo or a true shot of vaccine because it is allocated to individuals randomly.
This is "blinding," as it is called, removing the risk that individuals will act differently based on the care they receive, possibly skewing the outcomes of the study.
When will people who got placebo during trials get the real Covid-19 vaccine shots?
True vaccinations are given to them only after the tests are over and the findings are obtained, but people question that they are given a placebo when they experience a life-threatening illness like others.
As many governments are in the process of announcing the emergency use of their Covid-19 vaccines by the masses, there is a controversy as to when the actual one will be received by the thousands of people who received placebo shots in trials.
Why vaccine makers give placebo instead of real shot?
The need for more data for the trials
To equate the wellbeing of those who have been vaccinated with those who have not been, placebos are used. Vaccine experts say that it would be devastating for the outcomes, effectiveness and safety of the trials to vaccinate placebo groups early.
Scientists would no longer be able to equate the wellbeing of those who were vaccinated with those who were not if any of the participants who got placebo shots were to get vaccinated suddenly.
Those that were in a placebo category in a study are the last people who would get vaccinated.
Experts claim that the ability to obtain robust data regarding a coronavirus vaccine will vanish if a placebo community disappears from a clinical trial.
For example, preliminary findings don't indicate how long the safety of a vaccine would last. It is likely that over the course of months, the immunity given by a vaccine could fade. That decline would lead to a rise in the number of vaccinated people getting ill.
The vaccine would be long-lasting if both groups stayed at a low risk of infection.
What is pharma firms’ policy on its placebo group?
On December 10, the US FDA will take up this topic for consideration, as companies have yet to agree on a placebo community policy.
It is also possible for certain individuals in placebo groups to drop out of two vaccine trials to get the approved vaccines.
The roll-out could have a greater effect in such drop-out situations. The real results of the trials will depend on the remaining unvaccinated placebo group.