Updated: Mon, 15 Aug 2022 04:39 PM IST
Bharat Biotech on August 15 announced that it completed the development for phase 3 trials and booster doses for BBV154 intranasal Covid-19 vaccine.
The manufacturer said that two separate and simultaneous clinical trials were conducted to evaluate BBV154 as a primary dose (2-dose) schedule and a heterologous booster dose for subjects who have previously received 2 doses of the two commonly administered Covid-19 vaccines in India.
Data from both Phase III human clinical trials have been submitted for approval to the National Regulatory Authorities, it added.
What Are Nasal Vaccines?
Nasal vaccines are administered, as the name suggests, through the nose. More accurately called intranasal vaccines, these vaccines are liquids that can be given as a spray or through a dropper or syringe.
The most common nasal vaccine is FluMist, a nasal spray that uses inactivated flu virus to protect against influenza.
Intranasal vaccines are best suited to protect against pathogens that enter through the nose, like the flu or the coronavirus.
By mimicking the first step of natural exposure to an airborne pathogen, these vaccines help train a person's immune system at the potential place of infection.
Scientists have shown that the first immune response in the respiratory tract after a person is exposed to an airborne virus can influence how sick a person gets.
Intranasal vaccines could provide better protection than vaccines given through a shot in the arm.
How Nasal And Intramuscular Vaccines Are Different?
When you get a COVID-19 shot in your arm, the vaccine triggers a strong immune response in the cells near where you got the shot.
It also causes your immune system to produce some coronavirus-specific antibodies and other immune cells in other locations throughout your body.
When the coronavirus begins infecting cells in a person's respiratory tract, the immune cells nearby will start mounting a defense. Your body will also send anti-viral immune cells and antibodies from other locations to the site of infection.
But by the time enough coronavirus-specific immune cells gather around the infection site to stop the virus from replicating, the virus has likely already begun to spread throughout the body, making it difficult for the immune system to keep up.
Nasal vaccines mimic the virus in order to prepare the immune system against a virus, just like any other vaccine.
But importantly, they mimic the process of infection, too, and boost protective response within the mucosal immune system of the nose and throat.
In simple terms, intranasal vaccines are like knowing there is going to be a break-in and putting your guards in the right location before the trouble even starts.
(With agency inputs)