Moderna COVID-19 vaccine
A Palestinian medic displays a vial of the Moderna COVID-19 vaccine, at the health ministry, in the West Bank city of Bethlehem. Image Credit: AP

Moderna Inc said on Monday it had dosed the first participant in an early-stage study of a new COVID-19 vaccine candidate that could potentially be stored and shipped in refrigerators instead of freezers.

The company said its new candidate could make it easier for distribution, especially in developing countries where supply chain issues could hamper vaccination drives.

The early-stage study will assess the safety and immunogenicity of the next-generation vaccine, designated as mRNA-1283, at three dose levels, and will be given to healthy adults either as a single dose or in two doses 28 days apart, the company said.

Moderna also plans to evaluate the new vaccine, mRNA-1283, as a potential booster shot in future studies.

Last week, Moderna began dosing the first participants in a study testing COVID-19 booster vaccine candidates targeting the variant, known as B.1.351, that first emerged in South Africa.

The booster vaccine candidates, designated mRNA-1273.351, will be tested in a trial of both a variant-specific shot and a multivalent shot, according to the company's announcement.