On Sunday, the US Drug Administration approved a major use of blood plasma from people cured by Covid-19 to treat infected patients. A decision that pleases US President Donald Trump, much less the scientific community.
A “historic breakthrough” in violation of scientific rigor? On Sunday, August 23, US President Donald Trump welcomed the decision by the US Food and Drug Administration (FDA) to “urgently” approve a major use of blood plasma from people cured by Covid -19 to treat patients infected with coronavirus. But this administrative green light has aroused some of the scientific community who emphasize that there is no definitive evidence of the effectiveness of this type of treatment yet.
The FDA recalled that this technology had already been used on more than 70,000 patients, either in critical condition or in clinical trials since the onset of the Covid-19 pandemic in the United States. The US Bureau claimed that all tests performed suggest that patients who receive blood plasma containing a large number of antibodies have a significantly higher chance of surviving the disease than people who received plasma with low antibodies. It took no more for Donald Trump to describe this treatment as a “historic breakthrough” that would save “a large number” of people.
A treatment used since the end of XIXecentury
It has been several months since the use of blood plasma from individuals who survived Covid-19 has been one of the most promising treatment options, and some researchers even say “liquid gold“, due to the golden color of plasma. Several countries, including France, Austria or China, have also authorized the use of this treatment under certain conditions. “Clinical research and use in hospitals in fact indicate that blood plasma transfusions can reduce hospital stays and reduce the death rate,” said Joakim Dillner, epidemiologist at Karolinska Institutet in Stockholm, contacted by France 24.
The principle is simple: people who have over-competent disease donate their blood, from which plasma is extracted. It is then necessary to ensure that this fluid used to transport blood cells contains enough antibodies before it is injected into infected patients to increase their own defense against the disease. “We administer one dose per day as long as the virus is present in the body,” said Joakim Dillner, who found that “any presence of Covid-19 can disappear in two days.”
This technology has been used since the end of XIXe century to fight certain viral or bacteriological infections. It has been particularly experienced in the fight against Ebola virus and during previous coronavirus epidemics (Sars 2002 and Mers-Cov 2012). But its effectiveness has never been proven 100%.
Clinical trials that are difficult to perform
And this is still the case with Covid-19. What is missing is a randomized trial [aléatoire] controlled and it is very unusual for the FDA to approve a treatment without waiting for the results of such a test, “said Stephen Evans, a pharmaco-epidemiological researcher in the Department of Medical Statistics at the School of Hygiene and Tropical Medicine in London, contacted by France 24 This type of test is the holy grail of medical research because “without this phase, we can not be sure that it is really the use of blood plasma that is the source of the improvement of the patient’s condition and not another factor,” states the British researcher. This method “makes it possible to ensure that the effectiveness of a promising treatment has not been overestimated”, concludes Joakim Dillner.
The problem with randomized controlled trials of blood plasma therapies is the difficulty of conducting them. We have to recruit a large number of volunteers from inpatients and get enough plasma from ex-patients, which means that the epidemic must already be in an advanced phase, Joakim Dillner recalls. In addition, “it is also necessary to know how to measure the number of antibodies that are necessary in plasma for the treatment to be effective, which is difficult to do”, the Swedish researcher adds. That is why in the past these tests never succeeded before the end of the epidemic.
With Covid-19, the world does not have the luxury to wait, believes this researcher who understands the FDA’s decision to have taken liberties with the traditional validation procedure. A point of view not shared by Stephen Evans. According to him, the US Drug Administration gave a terrible blow to the work of researchers. “It will be much more difficult to do randomized blood plasma trials now because patients prefer to receive the treatment in hospital rather than participating in a randomized clinical trial where they are not sure they are in the group that the right treatment will be administered,” he said. he apologizes.
But for Donald Trump, the time for scientific research is incompatible with his election calendar. The FDA gave him a huge gift when the Republican convention begins on Monday that officially nominated him as the party’s candidate for the US presidential election in November.