(AP) — Johnson & Johnson
announced Thursday that US regulators have extended the expiration date on millions of doses of its COVID-19 vaccine
by six weeks.
According to the company, a Food
and Drug Administration review concluded that the shots are safe and effective for up to four and a half months, despite the fact that they were only approved for three months previously.
State officials had previously warned that many unused doses in storage would expire before the end of the month.
Expiration dates for vaccines
are determined based on data submitted to regulators by the manufacturer proving how long the shots stay at the correct strength. The vaccine was approved for use within about six months, but the FDA has been reviewing those expiration dates as companies have continued to test samples of batches in the months since the shots first went on the market.
The extension will help maintain vaccine supplies even as the country's rate of new injections continues to decline. The country averaged about 800,000 new injections per day last week, down from a high of nearly 2 million per day two months ago. Government officials have turned to a growing number of incentives to encourage shots, ranging from paid time off
to $1 million lottery
rates have slowed, it has become clear that the United States
will fall short of President Joe Biden
's target of having 70% of American adults partially vaccinated by July 4. According to the Centers for Disease Control and Prevention
, roughly 64% of Americans over the age of 18 have received at least one dose. J&J's vaccine was highly anticipated because of its one-and-done formulation and easy-to-ship refrigerated packaging.
However, rival drugmakers Pfizer
have already supplied more than enough doses to meet U.S. demand, with more than 129 million Americans fully vaccinated with the companies' two-dose shots, compared to only 11 million Americans with the J&J shot.
The United States is expected to announce plans to donate 500 million Pfizer vaccine doses for global use over the next year, in addition to the 80 million doses pledged by the end of the month.
Contamination issues at a Baltimore factory that helps manufacture the shots have also hampered uptake in the United States. The facility was closed after an FDA inspection uncovered multiple problems in April
, and none of the vaccines made there have been distributed.___AP Health Writer
Linda A. Johnson contributed to this story.