Johnson and Johnson COVID-19 vaccine: The US last week lifted the pause on the use of the single-dose COVID-19 vaccine developed by Johnson and Johnson. The pause was lifted by the US Food and Drug Administration (FDA), the drug regulatory authority in the country, and its Centers for Disease Control and Prevention (CDC), the nodal health agency of the US. The Johnson and Johnson vaccine is the only single-dose vaccination regimen developed by any manufacturer for the coronavirus as of now. Earlier this month, the vaccine developer had also reached out to Indian drug regulatory authorities, communicating its interest in holding bridging studies for the vaccine in India.
The reason behind Johnson and Johnson vaccine pause
The administration of the Johnson and Johnson vaccine had been paused in the US after there were six reports of people showcasing rare and severe types of blood clot after having been administered the vaccine. Such cases were mostly found to be present among women aged between 18 years and 49 years. During the use ban, the FDA and the CDC looked at the data to ascertain any type of risk or thrombosis, or the process of the clotting of blood, or thrombocytopenia, in which the blood platelet counts are low.
What has changed now?
Based on their assessment, the two US agencies determined that the Johnson and Johnson vaccine was safe to be used and was also effective in the prevention of COVID-19. The FDA also said that the known as well as potential benefits of the vaccine were enough to outweigh any possible risks among individuals aged 18 years or above. The CDC, on the other hand, said that while currently, the chances of TTS occurring were very low, the two agencies would continue to be vigilant in this regard and continue to investigate. Accordingly, now, the use of the vaccine would once again begin in the country, but it would come with a label warning about the possibility of the occurrence of a rare blood clot.
The working of the Johnson and Johnson vaccine
The Ad26.COV2.S, which is what the vaccine is being called at the moment, makes use of the genetic code of the SARS-CoV-2 to make the spike protein, like many other vaccines, because this is the protein using which the virus binds with the human cells. What it does with this code is, it injects this into the body, triggering the immune system and leading to the creation of antibodies in the human body. This way, when or if the actual virus enters the body of a vaccinated person, these antibodies help in the recognition of this actual virus and fight it off.
However, unlike other vaccines, which are mRNA-based, the Johnson and Johnson vaccine is a non-replicating viral vector-based vaccine, meaning that the genetic material which the vaccine contains would not replicate itself upon entering the human body.