Table 2.

Probability of success of different vaccine technologies.

Property\vaccine technology	Synthetic peptides	Vector based (virus or RNA)
Epitope targeting receptor binding domains (neutralization)	Specifically selected	No selection. The immune system of each individual will select and present the most dominating epitopes
Epitope presented and likelihood for getting local or systemic toxicity (SAE)	Low to very low. In theory no SAE should be observed since all epitopes are non-human like.	Difficult to predict The epitopes presented will be a mixture of human like (78.4%) and non-human like (21.6%) epitopes
Antibody-dependent enhancement (ADE)	Low Since the antibodies are directed towards the receptor binding domain and other co-receptor domains	Difficult to predict In such vaccine designs, there is no innate guiding of where the antibodies should bind. However, due to continued boosting of these epitopes through life, there is an elevated risk for development of ADE which must be expected due to the fact that if the virus returns at a later date in a mutated form, having modified antigenic composition, partial binding may occur and hence result in ADE (Ricke D, et al., 2020 ; Negro et al., 2020 ).