Ease of administration and dual protection of local and systemic immunity are promising drivers for intranasal vaccines’ adoption and compliance, particularly at a time when the mammoth task of prospective large scale vaccination is the need of the hour in the wake of the current COVID-19 pandemic, says GlobalData.

Late-stage clinical trials of intranasal COVID-19 vaccines are expected to begin in India in the coming months. Recently, India-based Bharat Biotech signed a licensing and distribution agreement with Washington University School of Medicine in St. Louis for a novel single-dose intranasal vaccine in all markets except the US, Japan and Europe. This is its second collaboration on intranasal vaccines.

Serum Institute of India has already started manufacturing Codagenix’s live-attenuated intranasal CDX-005 vaccine.

Sasmitha Sahu, Pharma Analyst at GlobalData, comments, “Although several parenteral vaccines for COVID-19 are expected to be launched post successful clinical trials, the actual efficacy and durability of immunity in real-world populations is uncertain. Despite India being the single largest manufacturer of vaccines in the world, it will be a mammoth task to cater to a world population of nearly 8 billion. Hence, alternative routes of vaccination like intranasal route of administration are gaining more research attention owing to their easy and non-invasive mode of administration.”

The intranasal route of vaccination triggers both local mucosal and systemic immunity and aims to provide more comprehensive protection.

GlobalData’s drug database shows that there are 17 intranasal vaccine candidates in the pipeline across multiple diseases, in Phase II and above, and eight marketed intranasal prophylactic vaccines, including three in India, all of which are for influenza.

Sahu adds, “The benefits of intranasal vaccines are yet to be fully realized in any other indication except in influenza. Regardless of the dearth of efficacy data, the growing number of trials of intranasal vaccine candidates is a confirmation for the need for alternative modes of delivery.”

However, unlike the influenza virus which replicates in the lower respiratory tract, COVID-19 virus was found to replicate in the nasal cavity and the upper respiratory tract.

Sahu concludes, “Traditional non-parenteral modes of vaccination like intranasal and oral do not need specific expertise for administration, facilitating rapid administration to large patient numbers, particularly during pandemics. Historically, other mucosal routes of vaccination have shown better adoption and compliance like in the case of oral polio vaccine that ultimately led to a better outreach of mass vaccination and complete eradication of the disease in populous nations like India.

“Due to novelty of these vaccines, appropriate dosage and formulation, designing proper delivery strategies and adequate real-world data around their safety and effectiveness on a periodic basis will be the other key factors that could favourably impact the adoption of intranasal vaccines.”