New beta-blocker for heart disease and angina

Aug 28 2008

Researchers at The University of Nottingham have been awarded £2.8 million by the Wellcome Trust to develop a new drug that could ease the suffering of hundreds of thousands of heart disease patients who are unable to take beta-blockers.

In the UK, 2.6 million people suffer from heart disease and most are able to have their symptoms effectively managed with the prescription of beta-blocker drugs which stop adrenaline from making the heart work too hard.

However, a major side effect of beta-blockers is that they make the symptoms of asthma and other breathing problems worse, so that around 300,000 patients in the UK who also suffer from respiratory conditions are prevented from taking them.

Now, a team of scientists from the University's Schools of Biomedical Sciences and Pharmacy will use the Wellcome Trust's funding, made under the Seeding Drug Discovery initiative, to conduct a three-year study to develop a modified type of beta-blocker that will treat heart disease and angina without exacerbating any underlying respiratory problems.

If successful, the new drug could become the general medicine of choice for all heart patients because its targeted action will lead to a significant reduction in overall side effects.

Even the best currently available beta-blockers are poor at discriminating between the heart and lungs, causing the muscles in the lungs to tighten and making breathing more difficult in some patients who have a pre-existing lung complaint.

In patients suffering from asthma, in which environmental factors cause muscle contractions leading to a narrowing of the airway, taking these medicines can trigger an attack or, even if tolerated enough to be taken regularly, can stop other asthma drugs from working.

Doctors are also extremely wary in prescribing beta-blockers for patients suffering from heart disease and chronic obstructive pulmonary disease (COPD), a progressive condition which causes the destruction of lung tissue and increased mucus production, because any reduction in respiratory function that may be caused by the drugs could have a major impact on symptoms.

The Nottingham scientists have already developed a molecule that is much more effective at discriminating between the heart and lungs than current drugs. The funding will allow them to carry out further studies to improve the molecule to ensure that it is able to target the heart cells more effectively - therefore directing the therapeutic effect only to the heart and not the lungs. The aim is that the resulting drug will be long-lasting and could be taken orally.

Leading the research, Dr Jill Baker from the School of Biomedical Sciences said: "Once developed, this molecule will cause much less wheezing and shortness of breath and should be able to be given safely to the hundreds of thousands of patients with both heart and lung diseases. Furthermore, because it will have so few side effects, it has the potential to become the beta-blocker of choice for all heart patients."

Dr Ted Bianco, Director of Technology Transfer at the Wellcome Trust, said: "We know that beta-blockers save lives in patients with heart disease, so making them safe for those unlucky enough to have a respiratory disorder as well is a clinical imperative. I applaud Jill Baker for questioning why beta-blockers should remain contraindicated for so many of her patients, and being stirred to correct this with an incisive programme of work. In the best traditions of medical research, this endeavour was born out of a problem encountered at the sharp end of clinical practice."

http://www.nottingham.ac.uk/