A blood thinner normally injected into patients at risk of clots can help ease chronic lung diseases when it’s inhaled.
Researchers at the University of Portsmouth found that heparin, a drug that has been around for more than 100 years, significantly improves lung function and breathing in patients with chronic obstructive pulmonary disease (COPD).
COPD, which affects around a million people, is an umbrella term for lung diseases such as emphysema and chronic bronchitis; patients find it difficult to get air in and out of the lungs, partly because the airways become inflamed and narrow.
The main cause is smoking, but pollution and genetics have also been implicated. Over time, the walls of the airways thicken and mucus is produced, which worsens symptoms.
One of the first signs is a cough, but it eventually causes extreme breathlessness and wheezing.
Treatment involves medication, often through nebulisers, to reduce inflammation and allows more oxygen into the lungs, or exercise programmes to bolster lung capacity.
Now UK scientists have discovered that turning the drug heparin into an aerosol, which can be inhaled through a face mask, can boost patients’ lung function.
Heparin is normally used in injection form for patients at risk of a blood clot, such as those who’ve recently had surgery or have a faulty heart rhythm.
The drug binds to a protein in the blood which stops it clotting. But research has found the structure of the heparin molecule means it has potential roles in other treatments, according to Janis Shute, a professor of respiratory pharmacology, who led the new study at the University of Portsmouth.
For example, a laboratory study found that heparin has mucus-thinning properties, making it potentially useful for helping clear a patient’s airways.
To test this, the Portsmouth scientists reformulated heparin into fine particles that could be inhaled as an aerosol, and put these particles into a device connected to a mask which contained a propellant gas that would force it into the lungs.
In a pilot study involving 40 COPD patients, inhaled heparin was found to boost lung function by at least 10 per cent within days of treatment starting, and this made it significantly easier for patients to breathe in more air, according to a report in the European Respiratory Journal.
The patients had the treatment twice a day for three weeks, with each session lasting 15 minutes. Professor Shute said: ‘Heparin thins mucus in the airways, which allows patients to clear their airways more easily, but it also acts as an anti-inflammatory.’
It’s not clear yet whether COPD patients will need to inhale the drug every day, or just when symptoms are particularly bad.
The researchers are now planning a trial to see if heparin inhaled daily can benefit patients with cystic fibrosis, the genetic disorder that causes lungs to become seriously congested with mucus.
‘Nothing we have at the moment does anything to the mucus levels, and it’s a huge problem,’ says Jorgen Vestbo, a professor of respiratory medicine at University Hospital South Manchester NHS Foundation Trust.
14 May 2018