Moderna and Pfizer Vaccine Trial Participants Report Serious Side Effects

Three patients taking part in clinical trials for Moderna's coronavirus vaccine candidate and two taking part in Pfizer's study have experienced intense side effects, according to a report published by CNBC. Those effects included high fever, pounding headaches, intense chills, and exhaustion.

Both of the trials in question are phase 3 studies. Pfizer - along with BioNTech, the Germany-based biotech it is partnering with -- and Moderna are considered by many to be among the front-runners in the race to bring a coronavirus vaccine to market.

For now, however, no COVID-19 vaccine has completed a full series of clinical trials and reported data sufficient to warrant calling it a success, nor have any candidates been approved by a major regulator.

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