Since the early days of the COVID-19 pandemic, researchers have been looking at convalescent plasma as a way to battle the virus.
Clinical plasma trials are now underway through the Lunenfeld-Tanenbaum Research Institute (LTRI), located at Mount Sinai hospital in Toronto.
What is convalescent plasma?
Blood is essentially made up of three components – red blood cells, white blood cells and plasma.
When a person gets infected with a virus, their immune system launches a response and antibodies are created to fight off the virus. Convalescent plasma refers to plasma obtained from the blood of such a person, which contains those antibodies after they’ve recovered.
How is the clinical trial conducted?
The LTRI clinical trial is called “Concor” and began just over a month ago – approximately five months after COVID-19 first made it’s appearance. Usually, clinical trials take several years to develop.
The trial is conducted on patients who have been admitted to hospital with a severe case of COVID-19 and require oxygen.
Patients are approached by a research coordinator to determine if they are eligible for the trial. They then explain the trial, its benefits, and risks.
“The majority of people that come into hospital really want to be part of the clinical trial,” said Dr. Michael Fralick, a clinician scientist working on the Concor trial.
Once enrolled, patients are then randomized to receive either convalescent plasma or standard of care – which refers to the regular course of hospital treatment for COVID-19, without convalescent plasma.
“If an individual is diagnosed with COVID-19, their immune system will mount a response and their immune system will generate these antibodies. The goal with giving them plasma is to give them that … extra boost of antibodies to help them fight the infection,” Fralick explained.
So far, about 60 patients have been enrolled in the clinical trial across different hospitals in Toronto and the province.
Is it working?
Fralick said preliminary data is encouraging and suggested there might be a benefit to administering convalescent plasma to COVID-19 patients — citing a study in China that had to be cut short because they simply ran out of patients to enroll.
Convalescent plasma is known to be safe, but the current trials are aiming to find out whether it’s actually effective in the fight against COVID-19.
As the study is still in the early stages, it’s still wait and watch.
“In order for us to know – is this curative or not – we need results from the clinical trial,” Fralick said. “Is it life saving? The only way we’ll know that is by completing the clinical trial Mt. Sinai is involved with as well as other clinical trials of this treatment.”
Fralick said they have to resist the temptation to look at the data too early — more patients need to be recruited into the study to get a definitive answer.
“There’s risks with everything in medicine. So we want to make sure that this has clear benefits before we roll it out to anyone who gets COVID-19 and is hospitalized.”
How can you donate plasma?
In order to donate plasma to be used in the clinical trials, there are some basic criteria that need to be met:
- You must be under the age of 67
- You must be completely recovered from COVID-19
- A month has passed since your recovery
Convalescent plasma is collected by Canadian Blood Services.
For more information on eligibility criteria and how to donate click here: Convalescent plasma donation
If I donate plasma, can they tell me if I had COVID-19?
Convalescent plasma donations are accepted from people who have recovered from COVID-19.
Testing for antibodies is able to detect residual traces of COVID-19, but currently, this type of testing is not aimed at determining whether or not a person had the virus. Tests to detect only whether a person had the virus in the past are currently not available.
Dr. Anne-Claude Gingras, Senior Investigator at LTRI, said there’s not much the average person can do with that information.
“You don’t know what that means in terms of – will it protect you from further infection?” she said.
She said the serology testing currently underway at LTRI is working to determine among other things:
- A better way to measure whether a person had the virus in order to track population health
- What type and how much of the antibodies were generated, when and how fast they were generated and how long they stay in the system and whether all those values relate to good vs. bad outcomes
- Whether those antibodies will prove to be protective if the person were to get infected again and how long would they last
- How this knowledge will further inform how to respond if one is infected again
Antibody testing is also being conducted to determine how prevalent the virus is in the Canadian population. Dr. Gingras said the LTRI study is associated with a government pilot program that is testing about 100,000 samples acquired through blood donations.
While each individual will not be called back with results, the findings of the study “should indicate whether they think that the prevalence rate is higher or lower than people have been guessing,” Dr. Gingras explained.
The results of that study are expected within a few weeks.