Contrary to some media claims, neither CanSino Biologics’ Convidecia Air nor Bharat Biotech’s BBV154 are the first inhaled COVID-19 vaccines to market, according to GlobalData, which highlights that two such vaccines were approved in Russia in March and July this year. However, the leading data and analytics company notes that the trend towards inhaled vaccines is a positive move, as they have the potential to build ‘mucosal immunity’, where the COVID-19 virus is ‘blocked’ from entering the body via the nose, throat or lungs.
Janet Beal, Senior Research Analyst in Health Economics and Market Access at GlobalData, comments: “As the current set of intramuscular COVID-19 vaccines reduce the likelihood of severe infection but do not block transmission, and vaccinated individuals can pass on infection while asymptomatic, there remains a high risk of being stuck in a cycle of ‘waves’ of infection, despite high primary and booster vaccination rates, as we try to emerge from the pandemic. However, if these new inhaled vaccines generate mucosal immunity, as has been demonstrated for other inhaled or oral vaccines against several pathogens and allergens, they could effectively block COVID-19 viral entry across the mucosa and subsequent transmission, representing a step-change in our global emergence from the pandemic—a way to break the cycle.
“The current evidence base for such activity from human clinical trials of inhaled COVID-19 vaccines is still relatively limited, but these initial four inhaled vaccines are likely to be the first of several coming through trials—with developers in countries ranging from the US and Japan to Cuba, Iran and Mexico.”
GlobalData’s World Markets Healthcare has documented that the first inhaled vaccine for COVID-19 to reach the market was a nasal spray version of the widely-approved injectable vaccine Sputnik V, approved in March 2022. This was followed by Salnavac, a nasal drop form of Sputnik V, in July 2022; Convidecia Air on September 4, 2022; and, most recently, BBV154 on September 6, 2022.
“While both of these vaccines received emergency approvals from a relatively limited evidence base (Phase I/II safety and immunogenicity data only), both are closely based on the well-established injectable vaccine Sputnik V, approved in many countries around the world. The Gamaleya Institute is currently planning late-stage trials, following a similar scheme to the pathway followed for Sputnik V itself, for which protective efficacy was only fully confirmed after the vaccine had received its initial emergency approval for public use. Both of these inhaled vaccines would normally be considered to have promise as boosters, with convenient administration and the potential to block infection. However, in the current climate under international sanctions, their export and use beyond Russia looks unlikely in the near term.”
