Intramuscular COVID-19 vaccines of Pfizer-BioNTech, Moderna, and Johnson & Johnson have been found effective against the virus, and now an experimental nasal vaccine is just a step closer.
Dr. Navin Varadarajan of the University of Houston and his colleagues have developed an intranasal subunit vaccine that shows promise in providing durable local immunity against inhaled pathogens, according to Medical Xpress.
The researchers published their findings in the journal iScience.
Dr. Varadarajan said, “Mucosal vaccination can stimulate both systemic and mucosal immunity and has the advantage of being a non-invasive procedure suitable for immunization of large populations.”
“However,” he added, “mucosal vaccination has been hampered by the lack of efficient delivery of the antigen and the need for appropriate adjuvants that can stimulate a robust immune response without toxicity.”
Dr. Varadarajan teamed up with Dr. Xinli Liu of the UH College of Pharmacy. They were able to encapsulate the agonist of the stimulator of interferon genes (STING) within liposomal particles to yield the adjuvant named NanoSTING, according to Medical Xpress.
The function of this adjuvant is to promote the body’s immune response.
Dr. Liu said, “NanoSTING has a small particle size around 100 nanometers, which exhibits significantly different physical and chemical properties to the conventional adjuvant.”
“We used NanoSTING as the adjuvant for intranasal vaccination and single-cell RNA-sequencing to confirm the nasal-associated lymphoid tissue as an inductive site upon vaccination,” Dr. Varadarajan explained. “Our results show that the candidate vaccine formulation is safe, produces rapid immune responses—within seven days—and elicits comprehensive immunity against SARS-CoV-2.”
The researchers said the nasal vaccine will also serve to equitably distribute vaccines worldwide.
Dr. Varadarajan said, “Equitable distribution requires vaccines that are stable and that can be shipped easily. As we have shown, each of our components, the protein (lyophilized) and the adjuvant (NanoSTING) are stable for over 11 months and can be stored and shipped without the need for freezing.”
Dr. Varadarajan is co-founder of AuraVax Therapeutics, a North Dakota-based pioneering biotech company developing novel intranasal vaccines and therapies to help patients overcome debilitating diseases, including COVID-19.
The company has announced that it has entered into an exclusive license agreement with the University of Houston with respect to the intellectual property covering the experimental intranasal vaccine. It has initiated the manufacturing process. The company plans to engage the FDA later this year.
