Although the original Covid-19 vaccines offer strong protection, especially after the booster dose, pharma companies have started testing new approaches like combination shots or nasal drops to see if they can keep up with the mutating form of the coronavirus.
According to news agency AP, Moderna and Pfizer are testing 2-in-1 Covid-19 protection that they hope to offer this fall. Each “bivalent” shot would mix the original, proven vaccine with an Omicron-targeted version.
In addition to this, Moderna recently stated that a Covid-19 booster designed to target the Beta variant as well as the original coronavirus generated a better immune response against a number of virus variants including Omicron.
The company said the results were a good sign for its plans for future shots targeting two Covid-19 variants.
BioNTech also said last month that it has expanded an ongoing clinical trial programme to develop new vaccines and patterns of administration for better protection against the dominant Omicron coronavirus variant.
Are nasal vaccines future-proof?
It’s hard for a shot in the arm to form lots of virus-fighting antibodies inside the nose where the coronavirus latches on. But a nasal vaccine might offer a new strategy to prevent infections that disrupt people’s everyday lives even if they’re mild.
However, nasal vaccines are tricky to develop and it’s not clear how quickly any could become available. But several are in clinical trials globally.
One in late-stage testing, manufactured by India’s Bharat Biotech, uses a chimpanzee cold virus to deliver a harmless copy of the coronavirus spike protein to the lining of the nose.
This comes as an ICMR-National Institute of Virology study has revealed that beneficiaries who have received both doses of the Covidshield vaccine but have no history of Covid-19 possess the least neutralizing power against Omicron’s BA.1 variant, as compared to patients who have recovered from the infection and also inoculated.
For the purpose of the research, serum samples were collected from 24 people who had never contacted Covid 180 days after they were administered with the second dose of Covishield. In addition to this, 17 people who had earlier recovered from Covid and were vaccinated with two doses of Covishield also gave their samples.
In the third group, 46 people who got SARS-CoV-2 breakthrough infection after two doses of Covishield were included. The serum samples of the third group were collected 14-30 days after their infection and out of the total, the complete genome could be retrieved in only 21 cases.
Researchers found that all samples neutralized B.1, Beta and Delta variants more effectively than Omicron.
However, the average concentration of neutralising antibodies in the samples of Covid naive were found to be lowest against Omicron — at 0.11, while it was 11.28 and 26.25 in case of breakthrough cases.
The NIV had earlier also stated after a study that the antibody level of the double dose of the Covid vaccine waned after six months with regard to the Omicron variant.