ENGLEWOOD, Colo. (CBS4) – Doctors at Swedish Medical Center waiting on a decision by the Food and Drug Administration about a booster shot for COVID-19 vaccines say more time should be spent studying the idea. An FDA panel will discuss on Friday whether another dose of Pfizer and Moderna vaccines would benefit healthy adults who already have two doses.

“These studies have certain limitations and the data is not compelling one way or another,” said Dr. Jaya Kumar, chief medical officer at Swedish, which is located in Englewood. “The protection may still be there, we’re not sure if it will add anything to it.”

Kumar and other experts say people who are immunocompromised would benefit from a third dose but still want to see additional research on whether a booster shot is needed for the general population like other vaccines have required in the past. Both Pfizer and Moderna are recommending the FDA move forward with this idea, with Pfizer providing evidence that their vaccine loses effectiveness in six months but improves with a third dose.

“This virus is a novel coronavirus and there’s no data on how long the protection from a booster will last,” Gov. Jared Polis said on Monday.

Polis supports the plan for booster shots, calling on the FDA to approve it at a news conference earlier in the week. But the governor acknowledged there is not as much research available on its impact. He announced plans to have Pfizer patients begin receiving booster shots on Sept. 20, Moderna patients could get their booster shot a few weeks later. In both cases, people would receive another dose based on when they got their second shot.

“We’ve come along way and there’s a long way to go. Let’s not be impatient,” Kumar told CBS4 on Thursday.

While the U.S. does not lead the world in vaccination rates, it is above the global average with many more countries struggling to get doses and shots into arms. Some have called on the U.S. to donate more of its supply and make vaccinating the rest of the world with initial doses more of a priority than a booster shot for Americans. Experts are divided on whether the country can do both at the same time.

The Colorado Department of Public Health and Environment told CBS4 on Thursday that in the past the state donated 199,780 doses of Moderna and 100,620 doses of Pfizer back to the federal pool between May 21 and June 10. The federal government can then decide what to do with the additional supply of vaccine. Moving forward, CDPHE says it is only asking for vaccine as it needs it and will take into consideration what supply will be required for booster shots.

There is no state plan for a booster shot of the Johnson & Johnson vaccine, the FDA has yet to announce the potential for another dose pending more research.