Pfizer officials will meet with U.S. scientists about booster shots, which officials say aren’t necessary now.

Dr. Fauci said Sunday that there was no evidence at this point that booster shots were needed for either Pfizer-BioNTech or Moderna vaccines, which require two doses, or the one-dose Johnson and Johnson vaccine.

“Right now, given the data and the information we have, we do not need to give people a third shot, a boost,” Dr. Fauci said on CNN’s “State of the Union,” though he added, “There are studies being done now ongoing as we speak about looking at the feasibility about if and when we should be boosting people.”

At least one outside infectious disease expert, Dr. Carlos Del Rio of Emory University, criticized Pfizer-BioNTech for creating confusion and staging a “publicity stunt.” He also complained about Monday’s meeting being conducted in private instead of by the C.D.C.’s advisory committee on vaccine practices, known as A.C.I.P., which will ultimately make a recommendation on whether booster shots are necessary.

“I want to see the data and I think they should present it in an A.C.I.P. session,” Dr. Del Rio said, adding, “It’s very inappropriate of the company to, first of all, announce that we’re doing this, second to say we need a booster where there’s no evidence for that.”

Since the onset of the pandemic, Pfizer-BioNTech have pursued a “get to market first” strategy in manufacturing and marketing their coronavirus vaccine.

The companies did not take federal money or participate in Operation Warp Speed, former President Donald J. Trump’s fast-track vaccine initiative. They were the not only the first to win F.D.A. authorization for their coronavirus vaccine, the first to use novel mRNA technology, but also the first to gain authorization for their vaccine’s use in adolescents.

The strategy has “paid off as handsomely as anyone could ask for,” said Steve Brozak, president of WBB Securities, a research investment bank focused on biotechnology.