All I know about it is that it can be stored in a regular refrigerator as opposed to a deep freeze. Looking up more:

The two-dose vaccine works by introducing a protein that prompts an antibody response, which blocks the ability of future coronavirus to bind to human cells and prevents infection. The protein is combined with Novavax's Matrix-M adjuvant, which is important in enhancing the immune response elicited by the protein antigen.

 Okay, so what this means is, the other vaccines were based on mRNA to make the body create the spike protein, while novavax is the spike protein itself.