Vaccine trial suspension is an expected response after reports of a single adverse event. It shows that proper protocols are being followed to determine if it is related to the vaccine. Phase 3 trials are designed to determine how larger and more diverse population groups respond.

Medical Mythbusting Commentary for September 9, 2020

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AstraZeneca’s COVID-19 shot trials on hold after suspected reaction

Should We Be Worried About COVID-19 Vaccines In Development?