Corrections & Clarifications: The American Red Cross collected plasma in Tucson from a recovered COVID-19 patient on April 12. Information about the earliest donor in the state was incorrect in an earlier version of the article.

A Phoenix-area man who tested positive and fully recovered from COVID-19 donated his blood plasma April 15 as a possible treatment for critically ill patients.

Mayo Clinic has partnered with blood donation company Vitalant in a pilot program to collect plasma from recovered COVID-19 patients to treat currently infected patients. The American Red Cross also is working on this effort through a program out of Tucson and at clinics nationwide.

Plasma is liquid blood once blood cells and platelets are removed. The idea is that recovered patients have developed antibodies in their blood — called "convalescent plasma" — to fight off the infection. If that is passed on to individuals struggling to fight the virus, it may boost their immune response.

Jack Schmittlein, 21, who had been studying abroad in Spain, returned home to Scottsdale early after the Europe travel ban. He had minor symptoms and decided to get tested when he found out his roommate in Barcelona had COVID-19. Schmittlein tested positive on March 18, tested negative on April 2 and has fully recovered.

His Mayo Clinic doctors encouraged him to donate his plasma — and to become the program's first convalescent COVID-19 plasma donor.

“I am just grateful that I came out healthy and I can turn around and help other people,” he said in a released statement. “If I can make a difference for just one patient, that is a great thing to do!”

COVID-19 is a new virus and there's not yet a vaccine or proven treatment. A number of clinical trials are well underway, but significant progress could still be months out.

In the meantime, plasma could be a solution, said Dr. Jill Adamski, chair of laboratory medicine at Mayo Clinic in Arizona. Adamski has been leading the clinic's convalescent plasma collection efforts in partnership with Vitalant.

"We're bypassing the need to have a vaccine, because we don't have one," Adamski said. "We're able to essentially give somebody the same immunity that they would have received could we have vaccinated them."

What is convalescent plasma?

Plasma has been used as a medical therapy since the early 1900s to fight off illnesses such as measles, polio, SARS, Ebola, H1N1 and other viruses. Recovered individuals have made antibodies to fight the disease and have developed immunity. Their blood plasma can help others to do the same.

The Food and Drug Administration is still investigating the use of convalescent plasma for treatment of COVID-19. It is allowing health care providers to use it in clinical trials or for patients and donors who meet certain conditions, but not yet for widespread or routine use.

"Essentially the FDA is blessing us to move forward to do these investigations and to try it, just because of the track record of doing this same thing over and over and over again every time we encounter a new virus that we don't have immunity against or a vaccine against," Adamski said.

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How can recovered patients donate?

People must have tested positive for COVID-19 to be considered as donors. At this point, that means they need to have a confirmed positive test result, which, given the limitations on testing, significantly decreases the pool of possible donors.

That may change with the addition of antibody testing to see who has COVID-19 antibodies, regardless of symptoms, in the weeks ahead. That will allow health professionals to find people who previously had COVID-19. But for now, the only way to be certain an individual had the virus and will have useful plasma is through a positive test.

"The only way that we can feel confident that the plasma that we're giving to patients is going to truly be able to help them is if we have positive confirmation that the donors were infected with COVID-19," she said.

Individuals must be symptom-free for 14 days and test negative for the virus to be considered to make sure the infection is completely out of their system. Their blood will also be screened for diseases such as HIV and hepatitis to make sure it's safe for recipients.

The Mayo Clinic is identifying patients and employees who have tested positive and recovered to be potential donors. It has multiple donors identified and ready.

"Presumably, they've made very good antibodies because those antibodies have allowed them to beat the disease," Adamski said.

Adamski said the response from the Mayo community has been "amazing," with many recovered and recovering individuals eager to donate. "It's just been really remarkable how the whole community is stepping up to the plate."

Although Mayo is beginning with its own patients and staff because it has access to those positive test results, others are also eligible to donate through Vitalant.

Individuals who have tested positive can sign up directly on Vitalant's website. Individuals can fill out a form here to volunteer as a donor.

The blood collection will take around 25 to 45 minutes, in addition to time for paperwork beforehand and eating afterward.

“As this life-transforming program continues to expand, we’re putting out a call to those who have recovered from COVID-19 to help patients in need,” said Cliff Numark, Vitalant’s chief of marketing, in a statement. “We encourage those who are eligible to go through the process to make a real difference.”

The American Red Cross also has a plasma donation program based in Tucson. The organization hopes to expand it to Phoenix in the future, spokesman Colin Williams said.

Those interested can sign up to donate online at the Red Cross's plasma donation webpage. Donors must be at least 17 years old, at least 110 pounds and in good health. As with Vitalant, potential plasma donors must have had a "prior, verified" COVID-19 diagnosis but are now symptom-free and fully recovered.

The Red Cross completed its first convalescent plasma donation for COVID-19 on April 12 in Tucson.

Plasma for patient treatment

After Vitalant collects the plasma from donors, the samples will be frozen and distributed to area hospitals like Mayo. They can then be thawed and given to patients as necessary.

A donor in one sitting can provide enough plasma for five doses for up to five patients, Adamski said.

FDA guidelines currently mandate plasma can be used outside of clinical trials only for patients with "serious or immediately life-threatening COVID-19." Those include critically ill patients who have life-threatening infections and are likely intubated in the ICU, Adamski said.

Other hospitals, like Mayo's Rochester headquarters, are doing clinical trials to treat patients with plasma before they become critically ill, such as patients who may be sick and in the hospital but not yet in the ICU.

Adamski expects that if trials and treatment are successful, convalescent plasma will be used widely to treat COVID-19.

She said it can be used for patients who have the virus and also "in theory" to protect individuals from getting the virus. Individuals at high risk who have come into contact with an infected person could be treated with plasma as a preventive measure.

Broader nationwide effort

Mayo Clinic has been leading a broader effort with several other academic institutions, the White House, the FDA and blood donor centers such as the American Red Cross to advance plasma as a possible treatment, Adamski said.

Their website www.uscovidplasma.org has a portal where physicians can request the plasma they need to treat patients and where potential donors can find donation locations.

If the treatment proves effective, the goal is to create a national repository of convalescent plasma to which any health care provider across the county will have access, Adamski said.

And plasma is not the only treatment in the works. Scientists, researchers and physicians are experimenting with a great number of methods to treat or cure COVID-19.

"It is unbelievable how many clinical trials there are in place," Adamski said. "This is a very promising therapy, but there are many other drugs that are being looked at right now and clinical trials popping up every day."

Reach the reporter at Alison.Steinbach@arizonarepublic.com or at 602-444-4282. Follow her on Twitter @alisteinbach.

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