Syringes with the Moderna COVID-19 vaccine are placed on a tray as vaccinations are given to Amazon employees at an Amazon fulfillment center on March 31, 2021 in North Las Vegas, Nevada. [Photo/Agencies] WASHINGTON - A new Phase 1 clinical trial has started in the United States to evaluate Moderna's investigational vaccine which is designed to protect against the B.1.351 coronavirus variant, the U.S. National Institutes of Health (NIH) announced on Wednesday. The trial, led and funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the NIH, will evaluate the safety and immunogenicity of the vaccine, known as mRNA-1273.351, in adult volunteers. The trial will enroll approximately 210 healthy adult volunteers at four clinical research sites in the United States, according to the NIH. "The B.1.351 SARS-CoV-2 variant, first identified in the Republic of South Africa, has been detected in at least nine states in the United States," said NIAID Director Anthony Fauci. "Preliminary data show that the COVID-19 vaccines currently available in the United States should provide an adequate degree of protection against SARS-CoV-2 variants. However, out of an abundance of caution, NIAID has continued its partnership with Moderna to evaluate this variant vaccine candidate should there be a need for an updated vaccine," Fauci said. The variant vaccine candidate differs from the currently-authorized Moderna vaccine in that it delivers instructions for making the SARS-CoV-2 spike that incorporates key mutations in the B.1.351 virus variant, according to the NIH. In addition to the Phase 1 clinical trial, investigators at NIAID's Vaccine Research Center are collaborating with Moderna to evaluate mRNA-1273.351 in animal models.