That underlines the need for new treatments for Corona virus.

But several existing medicines for other conditions are undergoing trials in the world's biggest study off potential treatments.

As our medical correspondent Fergus Walsh tells us now, what would the world give for a cure for Corona virus?

It has turned hospital wards into alien landscapes.

Stafford Addenbrooke's in Cambridge must be shielded from the highly infectious virus.

Patients like Peter, who's 89 must rely on oxygen.

One thing known to help fighting for birth is very bad.

That was on about Day three.

Those order, the tone on individuals and their families, has been enormous.

Yes, of more average.

Peter is part of a national trial, which is examining five drugs used for other conditions to see if they work for Corona virus until they get results.

Doctors have limited options, so it's extraordinarily difficult to what a large number of patients get so incredibly unwell on know that we have no therapies anywhere in the world that are proven to be efficacious.

It means that there's an urgent health need to do research in the space so that we can understand what treatments work on what date drugs for HIV and malaria are being tried to see if they can help stop the virus replicating in the body.

Other patients are being given treatments to reduce inflammation and dampened the immune system, which can go haywire.

Jeff, who's 60 has had cancer.

He can't shake off Corona virus after being infected six weeks ago.

Twice I've been pretty with chemo twice of four.

Emissions on the last one was certainly end of last year.

And then when you get this, he signed up for two clinical trials.

What support?

What's important company in the hospital be pumped full of all sorts of things on.

Nobody really knows what, what?

What there is okay, probably will help me, but, you know, But it might help people that followed behind me.

The first results of the trials could come as early as June.

It'll be here at the Big Data Institute in Oxford that the trial results will be analysed in a little over a month.

Around 8000 patients from nearly 170 hospitals throughout the UK have been enrolled in what is the biggest clinical study in the world into Cove in 19 treatments.

At the peak, we were enrolling 400 patients a day.

Lessons have been learned from the swine flu pandemic when experimental treatments were not properly assessed.

The best example is 2009 Pandemic, where tens of thousands of patients were treated with drugs outside of clinical trials and we didn't get any results.

We can't afford to do that again.

We need to know what works for covered 19.

And so these trials, I think of critically important you need don't expect to cure.

But even a treatment that is partially effective could save thousands of lives and pave the way for other, better medicines.

And Fergus is with me now.

Clearly and understandably, there is intense interest in the progress that scientists and others are making in this area.

So how would you sum up where we are in terms of the search for a cure?

Will you?

None of the doctors or scientists I've spoken to is expecting a magic bullet, something that will stop Corona virus in its tracks.

For the majority of patients, it's great that the trials are underway, but they are trying drugs that were developed for other conditions on what we should hope for, perhaps is a moderate effect from those if they are successful, say something that reduced mortality by 20%.

It may not sound much, but in the UK that could save thousands of lives.

Now in the US Tonight there are some early results from an antiviral drug originally developed for a bowler, which are being hailed, which seemed to suggest that it's cut the duration of symptoms in patients with Corona virus from 15 to 11 days.

But it comes off the back of some other data that suggested it didn't work.

And that's why these trials are so important.

We've got to wait for them to come through in the coming months on.

Then, of course, we've got to wait for the dozens of vaccines that Aaron Development.

So it's gonna be a long hole.