In a recent perspective published in Science, the authors discussed the critical nature of the comprehensive safety testing conducted in preclinical and clinical trials. The history of vaccine development has paved the way for ensuring a coronavirus disease 2019 (COVID-19) vaccine is both safe and effective, according to the authors.1,2

Regardless of the urgent need for COVID-19 vaccines, the perspective said researchers must remain focused on ensuring safety and public confidence in vaccines by following the established clinical safety testing protocols throughout vaccine development, which includes the stages before and after the deployment of COVID-19 vaccines.1,2

The authors noted that if regulatory agencies maintain the well-documented safety testing protocols that have been developed over the years, COVID-19 vaccines will be safe and trustworthy. These protocols include practices such as testing all batches of vaccines for safety before vaccine deployment.1,2

It is also important that developers understand the mechanism of action and immune correlates of protection in relation to the vaccine, according to the authors. This is critical to ensuring that vaccines are able to induce the optimal immune response for protection while not creating nonproductive or counterproductive immune responses.1,2 The authors also explained an important lesson from past vaccine development research, which taught development researchers that if serious adverse events (AEs) are detected during a clinical trial, it is critical that the researchers begin additional clinical testing before progressing things further.1,2

In current regulatory practice, it is necessary to monitor rare AEs before and after vaccine licensure. Upon the detection of serious AEs, the authors said the trial or the use of the vaccine should be put on pause. During current COVID-19 vaccine research, occurrences of such safety pauses have occurred, demonstrating the value of extensive regulatory safety protocols, which should be neither rushed or undermined.1,2

“There is an urgent need for COVID-19 vaccines and exciting progress to that end, but there remains a critical public health obligation to conduct rigorous evaluation to ensure safety as well as efficacy,” the authors wrote in the study. “Vaccines remain one of the most successful biomedical tools for prevention of disease. The urgent need for COVID-19 vaccines must be balanced with the imperative of ensuring safety and public confidence in vaccines by following the established clinical safety testing protocols throughout vaccine development, including both pre- and postdeployment.”1

REFERENCES
  1. Knipe DM, Levy O, Fitzgerald KA, et al. Ensuring vaccine safety. Science. 2020:eabf0357. doi: 10.1126/science.abf0357.
  2. Comprehensive safety testing of COVID-19 vaccines based on experience with prior vaccines. American Association for the Advancement of Science; November 17, 2020. eurekalert.org/pub_releases/2020-11/aaft-cst111720.php. Accessed November 20, 2020.