It comes days after the drugmaker announced that its vaccine appears 95% effective at preventing mild to severe COVID-19 disease in a large, ongoing study.
The data suggests that those aged over 70, who are at higher risk of serious illness and death from COVID-19, could build robust immunity.
A final analysis of the Phase 3 trial of Pfizer's coronavirus vaccine shows it was 95 per cent effective in preventing infections.
Airlines are now considering options ranging from a large plug-in freezer that can cost about as much as a small car to a multi-layered canister that uses liquid nitrogen to ship vaccines requiring a deep freeze.
Trump's defiant remarks comes amid a record breaking surge in new COVID-19 cases in the United States.
Pfizer cautioned the initial protection rate might change by the time the study ends. Even revealing such early data is highly unusual.
If it works, a vaccine would allow the world to return to some measure of normality after the tumult of the pandemic.