Current messenger RNA vaccines appear to offer at least some protection against new SARS-CoV-2 variants, including Omicron, especially for people who have received boosters. But manufacturing costs and the need for ultra-cold refrigeration have limited availability of these vaccines in low-and middle-income countries. That’s where emerging protein-based COVID-19 vaccines — including two candidates developed at Boston Children’s Hospital — could change the game.
Protein-based vaccines are potentially much cheaper to manufacture at scale than mRNA vaccines and may not require ultra-cold storage. This would help get more vaccines to parts of the world like Africa where vaccination rates are currently very low.
Existing COVID-19 vaccines are based on the full SARS-CoV-2 spike protein. In contrast, both Boston Children’s vaccines use just a portion of the spike, namely the receptor-binding domain or RBD. The RBD is the same part that latches onto our cells’ angiotensin-converting enzyme 2 (ACE2) receptors. But the two vaccines use very different methods to stimulate immune responses.
