The US Food and Drug Administration says it has authorised the use of Pfizer Inc's COVID-19 vaccine, with the first inoculations expected within days, marking a turning point in the United States where the pandemic has killed more than 295,000 people.
The US Food and Drug Administration on Friday granted an emergency use authorisation for the vaccine, developed with German partner BioNTech, which was shown to be 95 per cent effective in preventing the disease in a late-stage trial.
The FDA said the vaccine can be given to people aged 16 and older. Healthcare workers and elderly people in long-term care facilities are expected to be the main recipients of a first round of 2.9 million doses.
In a video posted on Twitter, President Donald Trump said the first vaccine would be "administered in less than 24 hours".
"The United states is the first nation in the world to produce a verifiably safe and effective vaccine. Today's achievement is a reminder of America's unlimited potential," Mr Trump said.
US health authorities, shipping services and hospitals stood ready to immediately launch a mass-inoculation campaign of unparalleled dimension.
Delivery companies United Parcel Service and FedEx Corp plan to ship millions of doses across the country under contract with the federal government, giving top priority to the vaccines on their airplanes and trucks.
Millions of Americans could begin getting vaccinated this month, especially if a second vaccine from Moderna Inc is quickly approved.
The Pfizer/BioNTech vaccine was first approved in Britain earlier this month, and UK residents began receiving the shots on Tuesday. Canada also authorised the vaccine and expects to start inoculations next week.
Mexico and Bahrain have also approved the Pfizer vaccine.
The authorisation has "huge importance," BioNTech Chief Executive Ugur Sahin said in an interview. "The emergency use authorisation allows us now to bring the vaccine at a time point which provides that extremely high medical need to the population," Professor Sahin said.
The FDA authorisation, known as an EUA, 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.
Margaret Keenan, 90, received the Pfizer-BioNTech COVID-19 vaccine at University Hospital in Coventry, England, on 8 December. Source: AAP
"The EUA was anticipated and it is one step in a sequence of steps that will bring this pandemic to an end," said Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security.
"I’m not going to feel that there is an EUA tomorrow when I’m taking care of COVID-19 patients. A lot of people will be infected, a lot will be hospitalised and a lot will die before the vaccine is able to have a meaningful impact on spread," he added.
Complex challenges
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.
Britain's health regulator has said there had been two reports of anaphylaxis and one report of a possible allergic reaction since rollout began. It advised some people with a history of anaphylaxis, an over-reaction of the body's immune system related to medicine or food, to avoid getting the vaccine.
The FDA in instructions to healthcare providers simply noted that "severe allergic reactions have been reported" outside clinical trials.
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.
'Some degree of normality'
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."
