How Blood Plasma From COVID-19 Survivors Could Save Lives
Promising treatments for COVID-19 are worryingly scarce.
There was some hope early in the pandemic that hydroxychloroquine would help, but researchers have found it could actually increase the risk of sudden cardiac death. Dr. Anonthy Fauci, arguably the most trusted American voice in this pandemic, recently said the drug remdesivir appears to speed recovery times, according to a study from the National Institutes of Health.
But there is another treatment, one that’s deceptively simple, and one that relies on what’s actually a growing resource right now: the blood plasma of people who’ve already recovered from the disease. One Tulane researcher believes it will be a “cornerstone” in the treatment of COVID-19. Here’s what you need to know — including how to donate.
First, a 101 on plasma
Plasma is the liquid part of the blood, and it contains important proteins, including antibodies. When someone recovers from an infection, they develop the antibodies to that infection in their plasma, explains Dr. Nakhle Saba, an associate professor of medicine at Tulane University who specializes in hematology and oncology.
Plasma is collected via the same mechanisms we use for donating blood. During this pandemic, when it seems many public health efforts must be created from scratch or ramped up to never-before-seen levels, blood donation is already well embedded in our health care systems.
And plasma actually has a long history as a treatment for diseases
“The story goes back to hundreds of years ago, when plasma collected from patients who had recovered from certain infections was used to treat those infections,” said Saba, who’s also the lead on the Tulane University study into plasma treatment for COVID-19. Similar studies are being conducted across the state, the country and the world, including research at Louisiana State University and a major national study comprising 46 states.
Convalescent plasma has been used to treat polio, the measles, influenza, Hepatitis B, Ebola and most recently SARS, “which is very close to the current virus COVID-19,” Saba said.
How it’s actually done is fairly straight-forward
The clinical study at Tulane, like others, has two components. The first is collecting the plasma.
Donors need to have had a documented infection from COVID-19. They also need to have completely recovered from the disease and be totally asymptomatic for 14 days.
“And there is a reason for that,” Saba said, “to give them enough time to make sure that they have enough circulating antibodies in their plasma, and also to make sure that the people who are collecting are safe. You don't want to send someone who still has the virus to the Blood Center or to whatever they have to donate to give their plasma. You don't want to infect other people.”
As with all blood donation, donors are screened for infections to ensure their blood is safe for others to receive. The entire process usually takes about two hours, Saba said, and each donor could give between 200 and 800 milliliters of plasma, or between one to four units of blood.
The blood is processed and can be stored for up to six months or transfused. And each donor can donate every month, Saba adds.
The second step is treating the patient. The Tulane study is testing plasma therapy on those who’ve had a documented case of COVID-19 in the past 14 days, especially those with severe disease symptoms, such as pneumonia. Patients have to consent to the treatment, and patients that are intubated need to have a proxy consent in their place.
“We give them medication to prevent reaction to the plasma, mostly with acetaminophen and an anti-allergic, and then we transfuse the plasma over one to two hours,” Saba said. “That's it. Just a single unit in most cases, one time, and then we observe patients on the go.”
Anecdotally, the outcomes appear promising
Tulane has treated a small number of people so far, Saba said, and he won’t give any definitive results. But the appetite to test this treatment is global. In the UK, thousands have signed up for a national study into the treatment and it’s been contemplated in the EU, Saudi Arabia and the Philippines, based on plasma therapy’s success in treating other diseases. Early reports — including one small study in China — offer “really good news,” Saba said.
But the true evidence will come from the results of the many plasma studies
“We do not have evidence that they work” yet, Saba said. And that’s what he tells patients.
“We tell them that based on anecdotal data, we know that there might be a strong signal that these antibodies work, and also based on historic data with viruses that are similar to COVID-19, such as SARS and MERS, where convalescent plasma therapy was used successfully,” Saba said. “We tell them that extrapolating from this anecdotal data and similar viruses, we think that this will help.”
Saba said he expects results from U.S. research, including the major national study, are perhaps weeks or months away.
COVID-19 antibodies could eventually have other uses, too
Scientists are also working to isolate the specific neutralizing antibodies for COVID-19, Saba said. Those could be concentrated into a vaccine, which would provide what’s dubbed “passive” immunity. And some are even looking at engineering these antibodies.
For now, though, plasma therapy is “like a shortcut” to delivering antibodies right now, before other treatments have been developed, Saba said.
Here’s how you can donate
To participate in Tulane’s study, you can visit their website to register or call 504-321-1740. Details on registering for LSU’s study are here. You can also sign up through The American Red Cross and The Blood Center.