The drug and vaccine pricing issue centered around federal procurement regulations stipulating that the contracting officers negotiate "fair and reasonable" prices. Democrats charged Republicans were seeking to undermine the existing rules to let drugmakers negotiate above-market rates, while Republicans said Democrats wanted additional restrictions that could hinder investment in new treatments and vaccine development.

"That's one of the disputes that is holding up the bill right now. Our Republican friends don't want to see the kind of limitations that we want to see," Senate Minority Leader Charles E. Schumer, D-N.Y., said Tuesday. He allowed that a bill could still be sent to President Donald Trump's desk as early as this week, however.

House Majority Leader Steny H. Hoyer, D-Md., told CQ Roll Call earlier Tuesday he hopes to hold a floor vote on the unreleased COVID-19 aid bill Wednesday. A schedule update released Tuesday evening said consideration was still “possible.” Hoyer said that if negotiators can't quickly reach consensus on drug and vaccine affordability provisions, they should put that issue aside for now.

Potential treatments won't be ready for a few months at minimum anyway, pharmaceutical executives told Trump on Monday. And government health officials reminded Trump that approval on a vaccine was at least a year away.

"We need to get resources quickly and if that cannot be worked out, my thought … would be that we would make resources available and then continue to work on that issue because it's a longer term issue," Hoyer said. "I think they are proceeding and hopefully we will have a bill on the floor tomorrow. What I've told the caucus is I don't expect us to leave here this week without passing a supplemental through the House."