"I think that this could be beneficial. It might be weakly beneficial," Gottlieb said on "Squawk Box." "It doesn't look like a home run, but right now we're looking for singles and doubles. There aren't really going to be any home runs on the horizon until we can get the other therapeutic antibodies on the market and hopefully eventually vaccines and better therapeutics."
The Food and Drug Administration announced on Sunday the emergency use authorization for using convalescent plasma to treat coronavirus patients. The Trump administration announcement came a day before the start of the Republican National Convention. President Donald Trump touted it as a "a breakthrough," just a few days after suggesting, without providing evidence, that opponents in the FDA may have been holding up emergency approval until after the Nov. 3 election.
Blood plasma treatment has cut Covid-19 mortality by 35%, Trump claimed on Sunday. However, results of the study by the Mayo Clinic that the FDA cited in its authorization of the treatment indicates that patients below age 80 who were not on a respirator and received plasma with a high level of antibodies within three days of diagnosis were about 35% more likely to survive another 30 days compared with patients who received plasma with a low level of antibodies. The study acknowledged, however, that its findings are limited, particularly because it did not have a placebo comparison.
Convalescent plasma is a century-old treatment that also was used on patients during the 1918 flu pandemic. It involves taking the blood from recovered Covid-19 patients who have developed antibodies against the disease, according to the Mayo Clinic, which is conducting studies on the treatment. The convalescent plasma is then given to people with the coronavirus, in hopes of preventing severe illness.
"We have a lot of experience using convalescent plasma in the setting of viral infections. We've seen situations where it does provide a benefit. We've seen some situations where it doesn't," said Gottlieb, who led the FDA in the Trump administration from May 2017 to April 2019.
In late March, in the early stages of the U.S. coronavirus outbreak, the FDA began allowing doctors to use convalescent plasma to treat Covid-19 patients on a case-by-case basis. In its release Sunday, the FDA stressed that clinical trials to determine its effectiveness "remain ongoing."
Gottlieb said he believed that convalescent plasma "certainly" met the standard for an emergency use approval "in the setting of a public health emergency."
"So the standard isn't the typical standard of safe and effective as it is for a new drug approval," he added. "I think on the basis of the data set that's available, it's reasonable to conclude that this may provide a benefit to patients who are suffering from Covid."
There are about 5.7 million confirmed cases of Covid-19 in the U.S., according to data compiled by Johns Hopkins University. At least 176,809 people have died. After a new surge of infections this summer, daily new cases of Covid-19 have started to decline.