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Covid-19 patient in intensive care unit: anti-inflammatory drugs could improve chances of recovery
Photo: Jefferson Bernardes / dpa / AP
The World Health Organization (WHO) has included three other possible drugs against Covid-19 in a large-scale, international series of studies.
Research teams from around the world can take part in the newly launched Solidarity Trial with as little bureaucratic effort as possible.
This is intended to accelerate the search for a drug against the Covid-19 disease caused by the coronavirus.
In a first step, four candidates and their combinations were tested last year, which were primarily intended to prevent the virus from spreading in the body.
However, these did not bring the hoped-for breakthrough in the therapy of Covid-19.
In the next phase, therefore, drugs that inhibit inflammation are to be tested.
This therapeutic approach has already proven to be very promising for seriously ill Covid 19 patients.
The effectiveness of these drugs against Covid-19 is now to be examined in more detail:
Infliximab
is a monoclonal antibody.
However, it is not directed against the coronavirus itself, but is used for therapy for autoimmune diseases such as Crohn's disease and rheumatoid arthritis.
It blocks a protein released by immune cells called macrophages, which promotes inflammation.
Imatinib
is usually used to treat cancer.
Researchers hope that it may bring therapeutic benefits in two ways.
On the one hand, it could prevent the virus from invading human cells and thereby dampen the spread of the pathogen.
On the other hand, it is said to reduce the activity of proteins that promote inflammation, so-called cytokines.
Artesunate
was originally developed to fight unicellular parasites that cause malaria.
It also has potential anti-inflammatory properties.
"We need drugs that we can deliver to many countries"
All drugs included in the study series have already been approved for the treatment of other diseases.
This has the advantage that they can be used quickly in clinical studies because they have already passed extensive basic tests.
Completely new remedies would first have to prove that they are well tolerated by humans.
That takes time.
However, it remains to be seen whether drugs against autoimmune diseases, cancer and malaria are actually effective against Covid-19.
The three active ingredients were selected because smaller studies have already provided indications of possible effectiveness and they are also available on a larger scale, said John-Arne Røttingen.
The Scientific Director of the Norwegian Public Health Institute heads the Steering Committee of the Solidarity Trial.
"We need at least promising signals that some of the active ingredients could work," he told the journal Nature.
"And we need medicines that we can deliver to many countries."
If a drug is found that reliably cures Covid-19 and prevents severe disease, it would be a breakthrough. Hospital beds remained empty, deaths would be prevented, and public life could pick up speed again. While vaccinations against the coronavirus could be developed at record speed, the big breakthrough in drug research is still a long way off.
The reason: unlike bacteria, which up to now could be reliably eliminated with antibiotics, viruses are much more difficult to get at with drugs.
In contrast to bacteria, viruses do not reproduce by themselves. They hijack the host's body cells and force them to produce countless copies of the pathogen.
Attacking viruses directly is therefore of little use.
Instead, they must be prevented from entering the cells in the first place.
When the Solidarity Trial started just over a year ago, research teams therefore focused primarily on drugs that can stop the virus early.
But the study results were sobering.
"None of the antiviral drugs had a strong effect on hospital patients," said Røttingen.
Presumably the funds were applied too late.
"The antiviral drugs could be of particular benefit if they are used very quickly immediately after the positive test," says Røttingen.
When the immune system runs amok
However, it has been shown that the anti-inflammatory drug dexamethasone can significantly improve the chances of recovery in seriously ill Covid-19 patients.
The remedy has long been used for other diseases, is widespread and inexpensive.
It especially helps seriously ill Covid-19 patients, for whom the virus is no longer the main problem, but an excessive reaction of the immune system.
The so-called cytokine storm leads to considerable inflammation and can be life-threatening.
Dexamethasone slows down the immune system and is already used as a standard drug for seriously ill Covid 19 patients in many countries, including Germany.
However, it does not bring the hoped-for success with all patients.
The studies that are now under way are intended to show whether other anti-inflammatory agents improve the chances of survival of seriously ill patients.
In contrast, the remedies are unlikely to be of any benefit to the mildly ill.
As long as there is no incorrect reaction, it would be counterproductive to inhibit the immune system of infected people.
That is why research into drugs that stop the virus early will continue.
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