More than 150,000 people have died with Covid-19, but no drug has yet proven to help doctors treat the disease.
So how far are we from these vital medicines?
What work is being done to find treatments?
Over 150 different drugs are being researched around the world. Most are existing drugs that are tested against the virus.
- The World Health Organization (WHO) has launched the Solidarity trial to assess the most promising treatments
- UK claims largest recovery trial in the world, with over 5,000 patients already participating
- And several research centers around the world are trying to use the blood of survivors as a treatment
What types of drugs might work?
Three main approaches are being studied:
- Antiviral drugs that directly affect the ability of the coronavirus to thrive inside the body
- Drugs that can calm the immune system – patients get seriously ill when their immune system overreacts and begins to cause collateral damage to the body
- Antibodies, from the blood of survivors or made in the laboratory, that can attack the virus
What is the most promising coronavirus drug?
Dr Bruce Aylward of the World Health Organization said that remdesivir was the only drug showing signs of efficacy after his visit to China.
The antiviral drug was originally designed to treat Ebola, but other options have proven to be more effective.
It has since been shown to be effective in treating other deadly coronaviruses (Middle East respiratory syndrome and severe acute respiratory syndrome) in animal studies, which suggests that it will also be effective against the Coronavirus Covid- 19.
Leaking results from trials at the University of Chicago also suggested the drug was working.
It is one of four drugs in the WHO Solidarity trial and its manufacturer, Gilead, is also running trials.
What should I know about coronavirus?
Can anti-HIV drugs treat coronavirus?
There has been much talk, but little evidence, that a pair of HIV drugs – lopinavir and ritonavir – would be effective in treating coronavirus.
There is evidence that they can work in the laboratory, but studies in people have been disappointing.
The combination did not improve recovery, reduced death or lower virus levels in patients with severe Covid-19.
However, as the trial was conducted in extremely ill patients (almost a quarter died), it may be too late for the drugs to work.
Can antimalarial drugs stop the coronavirus?
Antimalarial drugs are part of the Solidarity and Recovery tests.
Chloroquine and a related derivative, hydroxychloroquine, may have antiviral and calming immune properties.
Drugs have been brought to the fore as potential therapies for coronaviruses, largely due to President Trump’s claims, but there is still little evidence of their effectiveness.
Hydroxychloroquine is also used to treat rheumatoid arthritis because it can help regulate the immune system.
Laboratory tests have shown that it can inhibit the coronavirus, and there is anecdotal evidence from doctors saying it seems to help patients.
However, the WHO says there is no definitive proof of its effectiveness.
What about immune drugs?
If the immune system overreacts to the virus, it can cause inflammation throughout the body. This is useful in rallying the immune system to fight infection, but too much can cause collateral damage throughout the body and can be fatal.
- Coronavirus: its effects on the organism
The Solidarity trial is studying beta interferon, which is used to treat multiple sclerosis and reduce inflammation. Interferons are a group of chemicals released by the body when attacked by a virus.
The UK recovery trial is studying dexamethasone – a type of steroid used to reduce inflammation.
Can Survivors’ Blood Treat Coronavirus?
People who survive an infection should have antibodies in their blood that can attack the virus.
The idea is to take the blood plasma (the part that contains the antibodies) and give it to a sick patient as therapy.
The United States has already treated 500 patients with so-called “convalescent plasma”, and other countries are also involved.
- Plasma treatment to be tested
How long until we have a cure?
It is too early to know when we may have a drug capable of treating the coronavirus.
However, we should start getting test results in the coming months. It is much sooner than we will know if a vaccine (which protects against infection rather than treating it) is effective.
Doctors are testing drugs that have already been developed and are known to be safe enough to use, while vaccine researchers start from scratch.
Some completely new and experimental anti-coronavirus drugs are also being tested in the laboratory, but are not yet ready for human testing.
Why do we need treatment?
The most obvious reason for wanting treatment is that it will save lives, but it could also help lift some locking measures.
Effective treatment would essentially make coronavirus a milder disease.
If this prevented people admitted to the hospital from needing ventilation, the risk of saturation in intensive care units would be reduced, so controls over people’s lives would not have to be as tight.
So how do doctors treat patients now?
If you are infected with a coronavirus, then for most people it would be mild and can be treated at home with bed rest, paracetamol and lots of fluids.
But some people need more intensive hospital treatment, which involves oxygen support such as ventilation.
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