Experts are divided over FDA approval of plasma for COVID-19 treatment

Health experts are divided over the recent approval of convalescent blood plasma as a treatment for coronavirus patients in the US.

On Sunday, President Donald Trump announced the experimental therapy had been issued emergency use authorization by the US Food and Drug Administration (FDA).

The commander-in-chief lauded the news as a ”very big day’ and ‘truly historic’ just one day after suggesting, baselessly, that the FDA is waiting to approve treatments and vaccines until after the presidential election in November. 

At the same press conference, Health and Human Services Secretary Alex Azar noted a Mayo Clinic study in which there was 35 percent decrease in mortality among patients younger than age 80 who received plasma.

Some physicians and the American Red Cross have praised the approval and say they’ve seen plasma help save the lives of patients.

Dr Lawrence Young, a virologist at Warwick University in the UK, called the approval ‘great news’ and said he hoped hospitals in the country will be able to use the treatment regularly very soon. 

But others say the value of the treatment has yet to be established and say it might not be effective.

Dr Eric Feigl-Ding, an epidemiologist from Harvard, says the ’35 percent’ figure is misleading because the treatment was tested between two groups receiving plasma  and not against a control group. 

Convalescent plasma therapy is an experimental treatment in which plasma from a recovered COVID-19 patient is used on an infected patient in critical condition.

The hope is that the antibodies and immunity in the blood of a healthy person will be transferred to a sick person.

Ideally, the infected person will then develop the antibodies needed to fight off the coronavirus.

The treatment was first used during the Spanish Flu pandemic of 1918, a situation similar to the current pandemic.

People can donate plasma more than once, but have to wait several weeks after donating.

In April, the FDA allowed use of convalescent plasma to treat COVID-19 patients, but said it must be on a case-by-case basis, and patients who receive it must be experiencing conditions such as respiratory failure or multiple organ failure.

Doctors at UMass Memorial Medical Center in Worcester said they gave plasma to a patient who was near death. Within a few hours, his vital signs improved and he began to recover, WCVB reported.

Since April, the American Red Cross has collected  plasma from more than 14,000 donors and has distributed more than 32,000 products to hospitals throughout the country, according to a press release. 

‘This [emergency use authorization] will help ensure more patients have access to this potentially lifesaving treatment, providing greater hope to individuals and their families during this difficult time,’ the organization wrote.

Even physicians, such as Dr Justin Maykel, a colon and rectal surgeon at UMass Memorial, donated his plasma after recovering from the coronavirus.  

In May, a study from Mount Sinai in New York City compared 39 coronavirus patients who received plasma infusions compared to 156 who did not.

Researchers found patients who received plasma needed less oxygen support, were less likely die and more likely to be discharged from the hospital.  

Nearly 13 percent of plasma patients died and 72 percent  were discharged in comparison with 24 percent of control patients who died and 67 percent who were discharged. 

‘I just want to emphasize this point because I don’t want you to gloss over this number,’ HHS Secretary Azar said during the Sunday press conference, referencing the Mayo Clinic study.

‘We dream in drug development of something like a 35 percent mortality reduction. This is a major advance in the treatment of patients. This is a major advance.’

Trump claimed that more than 100,000 Americans have already enrolled to receive this treatment.  

But leading scientists say the study is a  ‘bad conclusion’ and that there is no conclusive proof that the treatment works.

The findings that led to emergency use authorization were published on a pre-print server, MedRxiv, on August 12. 

This means the research has not been peer-reviewed yet, a process in which scientists can scrutinize the findings – and often reveals flaws.

Among 35,000 coronavirus patients, the team said there were fewer deaths among people given plasma within three days of diagnosis and also among those given plasma with the highest levels of antibodies compared to less-rich plasma. 

Those treated with plasma containing the highest levels of antibodies had a 35 per cent lower risk of dying within a week compared to those treated with less-rich plasma. 

But it was not a formal study because patients were treated in different ways in hospitals around the country.

This means the Mayo Clinic cannot prove the plasma – as well as the other care they received – was the real reason for improvement. 

What’s more, experts say the ’35 percent mortality reduction’ is a misleading figure.

This is because researchers compared patients receiving plasma early on in infection compared to later, not plasma versus a placebo – the ‘gold standard’ of clinical trials. 

The findings show 8.7 percent of patients treated with plasma within three days of diagnosis died after seven days, compared to 11.9 percent who were treated four days or more.

That’s an absolute difference of 3.2 percent, not 35 percent, and not compared to a control group.

Additionally, the 35 percent figure comes from the relative risk of death in the high-plasma group as opposed to the low-plasma group after seven days. 

Former FDA commissioner Dr Scott Gottlieb told CNBC on Monday that blood plasma may work, but that it’s not the be-all and end-all treatment. 

‘I think that this could be beneficial. It might be weakly beneficial,’ he 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.’

Meanwhile, World Health Organization (WHO) says blood plasma is ‘experimental’ and that early results showing its success may are still ‘inconclusive.’ 

The WHO’s chief scientist Dr Soumya Swaminathan said studies looking at convalescent plasma have been small and provided ‘low-quality evidence.’