As Digital Journal’s Karen Graham has reported, Donald Trump has overridden the U.S. Food and Drug Administration and authorized the use of convalescent plasma (“see: “Trump pushes authorization by FDA to use plasma to treat Covid-19“). As Graham reports, Trump, speculating on August 23, 2020, proceeded to issue an emergency use authorization (EUA) for investigational convalescent plasma for the treatment of COVID-19 in hospitalized patients on Sunday August 23. This is a controversial step, given that the plasma treatment is still undergoing clinical trials and scientific assessment.
What is convalescent plasma?
Blood plasma is a yellow colored fluid and a component of blood that keeps blood cells in suspension (plasma forms around 55 percent of blood volume). Plasma contains proteins (around 700), some of which help blood to clot. The liquid also functions to transport substances through the blood. Blood plasma also contains glucose and other dissolved nutrients. About half of blood volume is composed of blood cells.
Convalescent plasma refers to a plasma therapy based on plasma or plasma derivatives obtained from donors having recovered from a severe infection. This plasma, after processing, is then infused into newly infected individuals. The basis of the therapy is with convalescent plasma being rich in antibodies (immunoglobulins) from those who have already tested positive, and then recovered from coronavirus. By giving this plasma, through infusion, to those who are struggling to develop their own immune system’s response, the aim is to help promote the infected individual to recover faster.
In the U.S., convalescent plasma has already been used on over 70,000 people under an Expanded Access Program launched in April 2020. The program opened up use to patients who were seriously ill or involved in clinical trials,
Implications of Trump’s actions
In overriding medical experts, Trump also displayed a lack of awareness of the use of convalescent plasma, stating that it was a ‘new’ treatment, despite convalescent plasma first being tried during 1918 Spanish flu pandemic (this had mixed results, although more recent success has been shown with plasma transfusion from selected donors in relation to the Ebola virus).
According to the science journal Nature, the actions of Trump has proved deeply concerning for researchers and clinicians around the world. Scientists are concerned that the new push to distribute blood plasma actually undermines the clinical trials needed to determine whether plasma therapy actually works against COVID-19. So far evidence in favor of convalescent plasma therapy against the SARS-CoV-2 virus is not yet strong enough for the treatment to be rolled out on a larger scale, according to FDA commissioner Robert Califf.
In addition, the Infectious Diseases Society of America has said in a statement, quoted by PharmaPhorum, that “we lack the randomised controlled trial data we need to better understand [convalescent plasma’s] utility in COVID-19 treatment”.
The reason for the concerns relate to trials that are taking place at the Mayo Clinic. While a lot of positives can be drawn from the trials to date, it would appear that the overall trial was not rigorous enough in that the transfusing convalescent plasma was also mixed with other therapies and activities. This should mean that further study is required. It is also possible that, given the properties of intravenous immunoglobulins, that the plasma was dosed too late to give the best effect in that by the time it was dosed the viral load could have be too high (this is speculation, given that the details have yet to be released).
Why scientific advice matters
Central to the development of a new medicine are clinical trials. While laboratory based testing can provide an assessment of how well a drug might work, and while animal tests can inform about the relative safety of a novel therapy, only human based clinical trials can bring everything together. A clinical trial is a study that prospectively assigns human participants to a health-related interventions in order to scientifically evaluate the effects of the intervention (be that a drug, medical device, or new surgical technique) on health outcomes (both safety and efficacy).
At the heart of the issue is the importance of independent scientific advice and the dangers of political bias. Medicines need to be examined on their merits as assessed carefully of efficacy and safety. Clinical trials take time. In the coronavirus era, while the public want rapid treatments, it should be the role of politicians to enforce other protective measures and to adequately fund research, and not to ride roughshod over informed opinion.
