Nate Billings / The Oklahoman via AP
Monday, April 27, 2020 | 2 a.m.
Doctors in Las Vegas say they are “cautiously optimistic” about a treatment for COVID-19 patients that has already been used to remedy the sick for more than 100 years.
The so-called convalescent plasma treatment takes antibodies from a recovered coronavirus patient’s blood plasma and gives it to another patient who is struggling to ward off the virus. Until there is a vaccine, our body’s last line of defense against the virus is our untrained immune systems.
“If someone has a viral infection and gets better, they make neutralizing antibodies to the virus which are part of the immune system that help us fight infection,” said Dr. Marc Kahn, dean of the UNLV School of Medicine. A hematologist by training, Kahn is coordinating with Vitalant, the blood collection nonprofit, and University Medical Center to collect blood plasma from recovered donors and eventually distribute it to the critically ill patients.
Each particle of the novel coronavirus cell is studded with spikes, allowing it to attach itself to human cells by poking a hole and burrowing inside, according to a University of Minnesota study. In this case, the virus infiltrates cells found in the lungs, hijacking all of their cellular machinery. That’s why the immune system sends out antibodies — its soldiers — which inhibit the virus from sticking to the cells, doctors say.
Those antibodies temporarily patrol your immune system, armed with the experience they need to ward off another invader. That’s why it is assumed that recovered COVID-19 patients are — at least temporarily — immune to the virus, doctors say.
But not every one makes enough antibodies to overcome the coronavirus — others don’t make them at all, Kahn said.
That’s where convalescent plasma treatment comes in, it essentially provides immune systems struggling to fight the virus reinforcements they need. The treatment was first discovered in the 1890s to treat patients with diphtheria. It has since been used to treat patients with scarlet fever, whooping cough, the Spanish flu and even the Ebola virus.
“It was a game changer back then and to an extent is now,” said Dr. Domenic Martinello, chief medical officer at Southern Hills Hospital in Las Vegas.
Southern Hills is in the early stages of using the treatment on at least one of its patients. While it’s still too soon to know how effective it will be in Las Vegas, Martinello said it’s safe to say he’s “cautiously optimistic” about it.
The risks are relatively low, Martinello said, especially when compared to drug therapy treatments like remdesivir or hydroxychloroquine.
“With anything there’s always risk,” he said. “We never get a free lunch with these sorts of things. With convalescent plasma, we don’t have large amounts of data, we just have historical data on how well this has worked on other diseases. With it being relatively low risk, with potential for a large benefit, is why we’re moving forward with it.”
While promising, the biggest limitation is getting an adequate amount of plasma, which at this time, can only be taken from recovered human COVID-19 patients.
“With diphtheria patients, they were using guinea pigs to develop serum and we were utilizing them to produce this. Whereas right now, the only production facility, so to speak, is human serum. So we have to find patients who not only were infected and recovered from it, but also maintained high enough levels of antibodies to be able to provide that to someone else.”
Southern Hills has been getting its convalescent plasma from the American Red Cross, Martinello said.
So far, Kahn has only found a handful of potential donors. He encourages anyone interested in becoming a donor to wait 28 days after recovery, and then visit vitalant.org to schedule an appointment.
“We need as many as we can get,” he said. “If people who got the virus and have gotten better want to help, one of the best ways they can do is give plasma.”