Two million doses will be delivered to pharmacies this week, up from 1 million.
Rep. Alexandria Ocasio-Cortez said the restrictions on high-flying stocks demand closer scrutiny from Congress.
Some see the market activity as a populist uprising that could eventually leave investors exposed to major losses.
Most American adults won’t get the vaccine probably until late summer, health officials said.
The action also orders reviews of other “extreme vetting” practices used by the Trump administration.
The move risks a shortage of vaccines when people’s second doses are due.
Treasuries jumped with the dollar as traders bet the prospect of divided government would make it harder to pass fresh stimulus.
Trump wants a capital-gains tax cut, but hasn
In some areas, the real number of infected people may be 12 times higher than reported infections.
Trump also said that a strong third quarter could cement his electoral chances.