The Meals and Drug Administration on Wednesday agreed to permit Johnson & Johnson to increase the shelf lifetime of its coronavirus vaccine to 6 months.

The F.D.A.’s determination got here as state health officials were growing increasingly concerned about whether or not doses of the vaccine would expire and go to waste. The vaccines had been beforehand set to run out after 4 and a half months.

In a letter, the F.D.A. stated its determination was “relevant to batches that may have expired previous to the issuance of this concurrence letter” and had been saved on the correct temperature, between 2 to eight levels Celsius, or 35.6 and 46.4 Fahrenheit.

The one-dose Johnson & Johnson vaccine may be saved at regular refrigeration, which has helped states attain extra remoted communities the place it might be tough to handle a two-dose vaccine like these made by Pfizer-BioNTech and Moderna. Each of these should be saved at a lot decrease temperatures.

As of Wednesday, greater than 13 million People had acquired the one-shot Johnson & Johnson vaccine, based on information from the Centers for Disease Control and Prevention.

The Pfizer-BioNTech vaccine has been probably the most extensively administered in the US, with greater than 87 million People totally vaccinated with it. Greater than 63 million individuals in the US have been totally vaccinated with the Moderna method.