As COVID-19 continues to evolve, there is an urgent need for vaccines that are cheaper, easier to produce, and more effective against emerging variants of concern. This is especially important for low-income countries, which face challenges in accessing current vaccines. Peter Palese and his colleagues – Weina Sun, Adolfo García-Sastre and Florian Krammer – at the Icahn School of Medicine at Mount Sinai are developing innovative new COVID-19 vaccines based on the Newcastle disease virus – or ‘NDV’. Read More
The team’s vaccines use a harmless version of NDV to deliver spike proteins from the coronavirus. This platform can be rapidly manufactured using the same facilities that produce flu vaccines. This means that countries with existing flu vaccine infrastructure can quickly and affordably produce NDV-based COVID-19 vaccines.
One of the team’s most promising vaccines is a trivalent formulation, which includes spike proteins from three different viral strains: the original Wuhan strain, the Beta variant, and the Delta variant. By including multiple spike proteins, these vaccines stimulate the immune system to produce a wide range of antibodies that can neutralize many variants – including distantly related strains such as Omicron. They can also be rapidly adapted to incorporate new spike proteins, allowing for even greater protection against new COVID variants.
In pre-clinical animal models, the team’s trivalent vaccine has shown remarkable success in lowering viral levels in the respiratory tract, which is a key measure of protection. It also prompted the production of antibodies capable of neutralizing newer variants, such as Omicron.
The team has also tested sequential vaccination strategies, allowing individuals to receive a vaccine based on one variant followed by a booster using a different variant. However, their studies suggest that combining multiple variants into a single vaccine preparation – consisting of a cocktail of three different vaccine variants – is more effective than the sequential approach.
Another innovative concept being developed by the team is an intra-nasal formulation of their NDV-based vaccine – consisting of a cocktail of three different vaccine variants. Intra-nasal vaccines offer many advantages over injections. By delivering the vaccine directly to the respiratory tract, intra-nasal formulations can provide a stronger defense at the site of infection. They should also be easier to store and could even be self-administered, which would be a gamechanger in regions with limited healthcare resources.
The team’s research could have profound implications for global vaccination efforts. Current mRNA vaccines require advanced manufacturing technology and careful storage, making them expensive and less accessible to many countries. In contrast, the NDV-based vaccines developed by Professor Palese and his team can be manufactured in large quantities at low cost. In addition, the mucosal/intranasal vaccine should reduce breakthrough infection and SARS-CoV-2 transmission. With ongoing trials and further development, these vaccines could play a critical role in increasing global access to COVID-19 vaccines and protecting against future variants of concern.