**6. ChAdOx1 nCOVID-19 (AstraZeneca)**

A new COVID-19 vaccine is currently in clinical trials; it was developed largely to prevent MERS [43]. This vaccine involves the genetic code of the SARS-CoV-2 spike protein inserted inside an adenovirus vector. The results of the phase 1/2, singleblind, randomized controlled trial revealed that the spike-specific T cell response

was detected on day 14, whereas the anti-spike IgG antibodies peaked on day 28. Neutralizing antibodies were generated in 91% of individuals after receiving the first dose and all individuals generated neutralizing antibodies after the booster dose. The safety and immunogenicity results for the ChAdOx1 nCoV-19 candidate vaccine support the entry of this vaccine into phase 3 clinical trials [44].
