A new drug aimed at preventing lung damage and blood clots caused by Covid-19 is set to be trialled in UK hospitals.

The drug, a molecule known as TRV027, targets specific cell pathways that are thought to drive severe illness in coronavirus patients.

Medics have suggested that up to a third of patients who are seriously ill with coronavirus are developing dangerous blood clots, which is one reason why people are dying.

Severe inflammation in the lungs, a natural response of the body to the virus, is thought to be behind formation of the clots.

Some 60 patients in UK hospitals will take part in the trial for the drug, which is supported by researchers at the British Heart Foundation Centre of Research Excellence at Imperial College London.

The study will follow patients for eight days during a critical period when some patients suddenly get worse and go on to need treatment in intensive care, often with ventilation.

Half of the patients will be given TRV027, and half the patients will be given a placebo.

The molecule – developed by the drug company Trevena – aims to restore the balance between two hormones, angiotensin II and angiotensin 1-7, which control blood pressure and affect blood vessels.

Usually, this balance is maintained by ACE-2, a specific protein that, in the case of Covid-19, appears to provide the entry point for the virus to infect a wide range of human cells.

In Covid-19, it is thought the balance tips towards too much angiotensin II which makes the blood become more sticky, leading to clots throughout the body, and in particular the lungs.

The drug TRV027 is thought to have a dual action by both blocking angiotensin II activity and also mimicking angiotensin 1-7 activity which opposes angiotensin II.

By restoring the balance, experts hope to be able to control the virus’s ability to cause damage to the body.

The drug has been tested as a treatment for heart failure and was shown to be safe.

Dr Kat Pollock, senior clinical research fellow in vaccinology and honorary consultant at Imperial College London, who is jointly leading the study, said: “We need to move away from thinking of Covid-19 as solely a respiratory illness – it also has devastating effects on the rest of the body, including the blood vessels and heart.

“When this infection was first described, we were surprised to learn that people with heart and circulatory diseases appeared to be at risk.

“Our study will play an important role in understanding the mechanisms which make Covid-19 so dangerous and offers a potential treatment.”

Dr David Owen, senior clinical research fellow and clinical pharmacologist at Imperial College London, who is also leading the study, said: “This virus poses a huge challenge for researchers because so much about it is unknown.

“In order to fight it, we need a team effort. This project has brought together pathologists, virologists, pharmacologists and researchers who usually focus on heart and circulatory diseases.

“Drawing on this range of expertise will give us the best chance of finding a desperately needed treatment for Covid-19.”

Professor Sir Nilesh Samani, medical director of the British Heart Foundation, said: “Without an effective vaccine for Covid-19, we urgently need to find new treatments which can reduce the damage caused by this virus.

“People with heart and circulatory diseases are at greater risk of experiencing a more severe illness, and it’s vital we find out why and tackle this increased risk.

“As part of the BHF’s contribution to the fight against Covid-19, we have given the green light for researchers at our centres of research excellence to mobilise behind research that could lead to improved treatments for people suffering from the virus.”