Injectable COVID-19 vaccines may not be the only preventative measure against COVID-19 as there have been advances in the development of both intranasal vaccines and nasal sprays against the coronavirus.
Experts highlight that the nasal COVID-19 vaccine has the potential to become a game changer because injecting the vaccine intramuscularly could only potentially protect the lower lung. However, it is thought that a nasal vaccine can protect both the upper and lower lung and could prevent transmission of the virus as well as an infection. Recent studies have shown that in the absence of mucosal immunity, the nasal cavity may become a reservoir for the coronavirus, putting the patient at risk for reinfection or disease transmission to others.
A novel nasal spray that appears to hold potential, is REGN-COV2, a formulation by Regeneron, based on delivery of recombinant adeno-associated virus (AAV) encoding for antibodies against SARS-CoV-2. Researchers anticipate that the nasal spray could be squirted through the nostrils, with the AAV entering nasal epithelial cells and hijacking their protein-making machinery in order to produce Regeneron’s monoclonal antibodies casirivimab and imdevimab. AAV causes only a mild immune response so the side effects could be less severe than the frontrunner vaccines, which work by training the immune system to recognise a key protein of the virus. Penn Medicine and Regeneron hope to complete their animal studies on the nasal spray by January this year, before applying to the Food and Drug Administration to begin human trials.
Some other noteworthy developments regarding nasal delivery of vaccines or other antiviral approaches are cited below:
- Indian firm Bharat Biotech will be commencing Phase I trials of its intranasal COVID-19 vaccine candidate in February-March 2021
- UK’s Open Orphan and Codagenix have dosed the first patient in a Phase I study with COVI-VAC, an intranasal COVID-19 vaccine candidate in January this year. Initial data from the study are expected to be reported by mid-2021. Pending positive results of this Phase I trial, the partnership expects to begin advanced clinical testing in mid-2021
- Australian biotech Ena Respiratory revealed that its self-administered nasal spray INNA-051, when taken once or twice weekly, reduced viral replication of SARS-CoV-2 by up to 96%, according to one animal study conducted by Public Health England, and a second study investigating the treatment in rhinovirus infection in human airway cells. The company believes its nasal therapy can complement the distribution of approved COVID-19 vaccines as rollouts commence around the world to help suppress transmission of the virus.
Enough scientific evidence is available that vaccines given through the nasal route are more effective than injected ones. And for the nasal spray, it is believed it could provide people with around six months of protection from a single dose and therefore complement vaccines well.
#vaccines #aav #COVID19 #regeneron #enarespiratory #codagenix #bharatbiotech
Sources
https://www.europeanpharmaceuticalreview.com/news/139089/first-patient-dosed-with-covi-vac-an-intranasal-covid-19-vaccine-candidate/
http://www.pharmafile.com/news/566658/ena-respiratorys-nasal-spray-reduces-covid-19-replication-96