Blog of Bloodworks Northwest

COVID-19, Bloodworks, and you: What is convalescent plasma?

Can plasma from a COVID-19 survivor help someone currently battling the disease? History says it’s possible, and Bloodworks is at the forefront of the work to prove it.

There’s still much we don’t know about SARS-CoV-2, the virus that has caused over 8 million confirmed cases of COVID-19 worldwide and resulted in 440,000 deaths.

An old treatment for a new virus

When a virus like SARS-CoV-2 attacks, the body responds by producing antibodies against the virus. Antibodies are proteins that can bind to foreign substances to help the body mount an attack against diverse pathogens, from viruses to bacteria and more. Antibodies play an important role in blocking the actions of the invading pathogen.

Convalescent plasma (also known as recovered plasma) may provide an effective treatment in the fight against COVID-19. The term refers to plasma, the liquid component of blood, that is collected from a person who is fully recovered from an infection: in this case, the SARS-CoV-2 virus. When patients recover, antibodies to the virus can remain in the blood plasma.

Convalescent plasma contains antibodies to SARS-CoV-2 and can help boost immunity in patients with active disease. Recent studies suggest that convalescent plasma, and purified antibodies to SARS-CoV-2, may be an effective therapy for COVID-19.

Bloodworks Medical Director Dr. Rebecca Haley explains, “Since the people who are getting COVID 19 have never had a chance to see this disease before, we want to take the plasma from the people who have already been through this process, take some of their antibodies, and see if we can help the new patients fight off the disease.”

Many scientists are excited about this possibility because similar therapies have enabled recovery from dangerous infectious diseases including tetanus, tuberculosis, the 1918 Spanish Influenza, and H1N1.

While convalescent plasma is potentially an important treatment option for a new virus, please note that it is not a vaccine or substitute for a vaccine.

How do we collect convalescent plasma?

Like many other blood donations, units of convalescent plasma are collected via an apheresis machine, and then receive a special tag to mark them specifically for use in COVID-19 patients.

The apheresis process filters out a desired blood component (in this case, plasma, where the antibodies live) and returns the rest of the blood to the donor’s body.

Each convalescent plasma donation can be split into several units, and, like all other plasma donations, can be frozen to extend longevity.

Bloodworks’ focus is on two forms of treatment: convalescent plasma therapy and purified antibodies (hyperimmune globulin treatment).

Convalescent Plasma therapy

Convalescent plasma therapy administers plasma directly to the patient in hopes that the antibodies will help their body fight off infection. You may have seen this form of convalescent plasma in the news or on Bloodworks’ social media. COVID-19 survivor Tom Hanks famously donated his celebrity plasma.

Bloodworks made national news when it collected Washington’s first convalescent plasma unit on April 10. Seattle resident Elizabeth Schneider was our first donor and we featured her on a recent episode of our podcast, Bloodworks 101.

Convalescent plasma treatment for COVID-19 has not been yet approved by the FDA, so is considered an investigational new drug (IND) that first must pass a series of clinical trials to be formally added to the officially-sanctioned treatment protocol.

Mayo Clinic and other researchers have been investigating the effectiveness of convalescent plasma as a treatment for COVID-19. In May, scientist-reported safety data from 5,000 patients concluded that convalescent plasma therapy is safe for severely ill COVID-19 patients. Further controlled studies will help us to understand if convalescent serum can be used as an effective treatment for COVID-19.

Because the clinical efficacy of convalescent plasma is still under investigation, doctors must register their patients in studies in order to receive this experimental treatment. In many cases, these patients have few remaining options for treatment.

Over the last three months, Bloodworks has collected enough plasma to meet the demand for eligible patients throughout the Pacific Northwest, including new hospital partners.

“We’re really proud to be able to provide that level of patient support,” said Bloodworks Medical Director Dr. Kirsten Alcorn.

Hyperimmune globulin treatment

Hyperimmune globulin therapy is a more precise form of antibody treatment; “globulin” means “protein” and “immunoglobulin” is another term for antibody.

Hyperimmune products are made by pooling, purifying, and concentrating large numbers of plasma donations, often in the hundreds or thousands. The benefit of hyperimmune globulin over therapeutic plasma is that doctors know exactly how many antibodies are in each dose administered.

Bloodworks is working with partners across the country to determine if concentrated antibodies can be an effective therapeutic to treat disease.

There is also a hope that the therapy can be used to preventatively treat people, like healthcare workers, who are at the highest risk of getting COVID-19.

For this portion of Bloodworks’ COVID-19 study, participants need to have a high titer (number) of antibodies in their blood. We draw blood samples from participants and send them to the NIH to determine their titer.

Bloodworks’ Expertise and Innovation

Convalescent plasma dovetails research and community donation in a departure from how blood centers like Bloodworks usually function. The study has been a monumental undertaking across the company, and every department within Bloodworks Northwest has played a role.

We currently have room for 60 plasma collections a week at our Central Seattle Donor center and Patient Services clinic, up from 30 at the beginning of the study. Our Contact Center staff have been working hard to book these appointments and fill spots for community blood needs.

But our reach extends beyond collection. We’ve been a world-class center for hematology and transfusion medicine since our start in 1944. By leveraging experts across the organization, we have been able to pull together experts in blood collection, blood science, and products.

Our renowned researchers and clinicians have worked beside our specialized product team to develop agile solutions for collection, processing, and distribution of biological products to researchers across the country, enabling Bloodworks to amplify the generosity of our donor community.

“Everyone continues to pull out the stops and get a lot done really fast,” said Aaron Posey, Executive Vice President of Bloodworks Bio.

To date, Bloodworks collected nearly 350 units for 23 participating hospitals and transfused around 150 units.

How to participate

We continue to recruit people with a confirmed positive COVID-19 test who have been recovered from COVID-19 for at least 28 days.

Please note: we are not testing for COVID-19, so even if you are relatively sure you had it but don’t have a confirmed positive result, you are not eligible to participate at this point.

Research participants must meet the criteria to donate blood as well as the following additional requirements:

  1. Age of at least 18 years at time of providing informed consent
  2. Legally qualified to receive study reimbursement
  3. Reliably capable of receiving US mail, electronic mail and telephone calls
  4. Anticipated to be available for scheduled donation(s)
  5. Donors must have been diagnosed with COVID-19
  6. Either:
    1. 28 days since positive screening
    2. 28 days since last symptoms
    3. OR a negative test

A donor can donate plasma every seven days, up to 20 times; donors with a high titer will be invited to participate as many times as possible. A typical plasma donation takes about 45 minutes. Qualifying participants are invited to donate plasma multiple times. Donations are confidential, and your identity is hidden from researchers by law.

If you are a regular blood donor, you will be deferred from donating to the community supply for the duration of your participation but know that your donations are as lifesaving as ever.

If you think you qualify, please fill out our pre-screening questionnaire.

If you are healthy and have never been diagnosed with COVID-19, donating blood is always a way you can support your community, and even amid the pandemic, it remains a safe activity.

And if you can’t donate blood, consider making financial gift.

Bloodworks continues to advance COVID-19 research and treatment. Stay tuned for more updates and information on our COVID-19 programs.

June 18, 2020 2:48PM

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