The United States Food and Drug Administration has authorised the Pfizer-BioNTech COVID-19 vaccine for emergency use.
US President Donald Trump confirmed in a video on Saturday that the vaccine had been given the greenlight, calling it a "medical miracle". It's expected that millions of highly vulnerable people could begin receiving the vaccination in the coming days, with Trump said the first dose would be administered in less than 24 hours.
"We have delivered a safe and effective vaccine in just nine months. This is one of the greatest scientific accomplishments in history," Trump said.
The outgoing President said it will save millions of lives "and soon end the pandemic".
"A vaccine will vanquish the virus and return life back to normal. The pandemic may have begun in China, but we are ending it right here in America."
He thanked those who worked on developing the vaccine, which he described as very safe.
"We have already begun shipping the vaccine to every state and zipcode in the country."
It's reported that the vaccine can be given to those over the age of 16. Healthcare workers and the elderly in long-term care facilities will be prioritised for the first round of 2.9 million doses.
The vaccine, which has been shown to be 95 percent effective, has already been approved in several countries, including in the UK, where it began its rollout this week. Doses are expected to become available in Canada sometime in coming weeks, while Mexico also authorised the vaccine on Saturday.
The FDA decision is a significant milestone for the US, which has seen more than 16.2 million people infected with the SARS-CoV-2 virus. According to Worldometers, more than 300,000 people have died from the respiratory illness COVID-19 in the US.
Dr Stephen Hahn, the FDA Commissioner, was reportedly told this week by White House Chief of Staff Mark Meadows that if the vaccine wasn't approved on Friday (US time), he should start looking for a new job.
The FDA authorisation comes at a time when infections, hospitalisations and deaths are soaring to record levels in the United States, which has failed to mount a coordinated effort to slow the spread of the virus. Earlier this week, the one-day COVID-19 death total topped 3,000, while hospital intensive care units across the country are nearing capacity, threatening to overwhelm healthcare systems.
Others with vaccines in advanced development include Moderna, which could win emergency US authorisation as soon as next week, AstraZeneca Plc with Oxford University, and Johnson & Johnson.
BioNTech began developing the vaccine in January, using a technology called synthetic messenger RNA (mRNA) that had yet to produce an approved product. The technology uses a chemical messenger to instruct cells to make proteins that mimic part of the new coronavirus, which the immune system learns to recognise as an invader. BioNTech struck a development deal with Pfizer in March.
The vaccine comes with complex distribution challenges as it must be shipped and stored at -70 Celsius (-94 F), requiring specialised ultra-cold freezers or supplies of dry ice.
Moderna's vaccine employs the same technology but does not need to be stored at sub-Arctic temperatures.
Pfizer has developed a special shipping container that will be filled with dry ice to keep the vaccine from spoiling. Many states are concerned about whether there is enough dry ice for shipments to rural areas that lack the specialised freezers, but Pfizer believes there should be sufficient supply.
The US quest for a vaccine has been the central response to the pandemic from a Trump administration that has mostly otherwise left states to fend for themselves. It has said it will have enough to supply all of the 330 million US residents who wish to be vaccinated by the middle of 2021.
The government has ordered 100 million doses of the Pfizer vaccine - enough to inoculate 50 million people - through its Operation Warp Speed virus development program and could negotiate for more. The status of those talks are unclear.
Pfizer board member and former FDA commissioner Scott Gottlieb said in an interview with CNBC earlier this week that the company had offered to sell the United States more doses as recently as last month but had been turned down.
The United States has agreed to buy 200 million doses of Moderna's two-dose vaccine. The government also has supply deals with J&J and AstraZeneca, but authorisation of those vaccines are not imminent.
Top US infectious diseases expert Dr. Anthony Fauci said if distribution goes well and enough Americans agree to get vaccinated, relief for a pandemic weary nation may be on the horizon.
"If we do it efficiently enough by the second quarter of 2021, and by the end of summer or end of third quarter, we may actually have enough herd immunity protecting our society," he said. "And as we get to the end of 2021, we could approach very much some degree of normality that is close to where we were before."
Newshub / Reuters