TAMPA, Fla. (WFLA) — Pfizer has begun shipping the first set of their COVID-19 oral antiviral treatment. On Twitter, the company announced the treatment has officially left their Memphis distribution center.

The oral treatment is not yet fully approved for use by the U.S. Food and Drug Administration, but received emergency use authorization for patients 12-years or older that are at high-risk for COVID-19.

“The good news is we have a product now that has about a 90% efficacy in preventing hospitalization, but the sobering news is, unfortunately, it is really a quite complicated and complex synthetic process,” White House Chief Medical Advisor Dr. Anthony Fauci said yesterday.

The White House COVID-19 Response Coordinator, Jeffry Zeints, said the federal government had already pre-purchased 10 million doses of the treatment courses, with full production of the Pfizer pill expected to take six to eight months. There will be fewer than 300,000 courses available by the end of January, according to Zeints.

While the Pfizer pill is the first antiviral oral medication to win authorization, Merck’s pill was approved by the FDA for emergency use as well. It was approved this morning.

Both pills come as the omicron variant of COVID-19 takes over as the dominant variant of cases in the U.S.