Moderna said on Wednesday the U.S. Food and Drug Administration has agreed to review its influenza vaccine after it had initially refused to do so, citing flaws in the trial design.

The FDA has accepted Moderna's revised approach seeking full approval for the shot for adults aged between 50 and 64, and accelerated approval for those aged 65 and above, the company said.

The company will also conduct an additional post-marketing study in older adults.

The regulator is expected to make a decision on the candidate by August 5.