Hope for thousands of men with incurable prostate cancer as trial reveals pioneering drug which targets faulty DNA ‘prolongs patients’ lives’
- Cambridge-based AstraZeneca revealed its trial has been successful
- Ovarian cancer drug Lynparza has extended lives of men with prostate cancer
- It works by targeting and destroying damaged DNA which is forming tumours
- Developers say their progress ‘meets a critical unmet medical need’
- It could benefit between 4,000 and 10,000 men with prostate cancer in the UK
A prostate cancer drug could offer hope to thousands of men with an incurable form of the disease after it succeeded in a clinical trial.
The medication Lynparza has hit its target of prolonging the lives of men with cancer which survived normal treatment.
Its developers say the drug is the only one to have worked in a field where ‘the need for new effective therapies is high’.
Lynparza works by destroying the damaged DNA of cancer cells and killing them, and has already been approved around the world for treating ovarian cancer.
Prostate cancer affects between 40,000 and 50,000 men in the UK each year and scientists say they may have found a way to prolong survival in those who have an incurable form of the disease (stock image of prostate cancer cells)
Cambridge-based pharmaceutical firm AstraZeneca today revealed its trial was going well and said it would present full results in the near future.
It said it had achieved ‘progression-free survival’ in a phase three trial – one which uses real patients to compare a medicine’s effectiveness to the current standard.
WHAT IS PROSTATE CANCER?
Prostate cancer is the growth of tumours in the prostate gland.
Only men have a prostate, which is a walnut-sized gland between the rectum and the penis which creates a fluid to be mixed with sperm to create semen.
How many people does it kill?
More than 11,800 men a year – or one every 45 minutes – are now killed by prostate cancer in Britain, compared with about 11,400 women dying of breast cancer.
It means prostate cancer is behind only lung and bowel in terms of how many people it kills in Britain. In the US, the disease kills 26,000 each year.
Despite this, it receives less than half the research funding of breast cancer – while treatments for the disease are trailing at least a decade behind.
How quickly does it develop?
Prostate cancer usually develops slowly, so there may be no signs someone has it for many years, according to the NHS.
If the cancer is at an early stage and not causing symptoms, a policy of ‘watchful waiting’ or ‘active surveillance’ may be adopted.
Some patients can be cured if the disease is treated in the early stages.
But if it diagnosed at a later stage, when it has spread, then it becomes terminal and treatment revolves around relieving symptoms.
Thousands of men are put off seeking a diagnosis because of the known side effects from treatment, including erectile dysfunction.
Tests and treatment
Tests for prostate cancer are haphazard, with accurate tools only just beginning to emerge.
There is no national prostate screening programme as for years the tests have been too inaccurate.
Doctors struggle to distinguish between aggressive and less serious tumours, making it hard to decide on treatment.
Men over 50 are eligible for a ‘PSA’ blood test which gives doctors a rough idea of whether a patient is at risk.
But it is unreliable. Patients who get a positive result are usually given a biopsy which is also not foolproof.
Scientists are unsure as to what causes prostate cancer, but age, obesity and a lack of exercise are known risks.
Anyone with any concerns can speak to Prostate Cancer UK’s specialist nurses on 0800 074 8383 or visit prostatecanceruk.org.
Lynparza is being compared with two testosterone-blocking drugs currently used by the NHS – abiraterone and enzalutamide.
Those drugs work by lowering levels of testosterone, the male sex hormone, which many prostate tumours thrive off.
Lynparza works differently by targeting damaged DNA to kill tumours and is meant for men whose cancers have continued to grow and spread even when their testosterone levels are medically reduced.
This condition is called metastatic castration-resistant prostate cancer (mCRPC).
It affects around 10 to 20 per cent of prostate cancer patients within five years of their diagnosis, AstraZeneca said – equal to between 4,000 and 10,000 men per year in the UK.
AstraZeneca is running the trial, named PROfound, alongside US pharmaceutical company MSD, known in the States as Merck.
Roy Baynes, MSD’s chief medical officer, said: ‘Metastatic castration-resistant prostate cancer is a deadly disease and represents an area of critical unmet medical need.
‘The Phase III PROfound trial is another example of MSD and AstraZeneca’s shared commitment to improving long-term outcomes for people living with cancer.
‘These results represent the potential for a new, oral targeted treatment option for this patient population.’
Prostate cancer is the most common cancer in men in the UK, and is diagnosed between 40,000 and 50,000 times per year.
It has a high survival rate – more than eight in 10 patients survive for 10 years or more after their diagnosis – but still results in around 11,000 deaths each year.
Doctors may not even want to treat prostate cancer in its early stages, opting instead to monitor a tumour.
But if treatment is decided upon it can involve surgically removing the gland, using radiation to destroy the cancer or taking hormonal medication to starve the tumour of the testosterone it uses to grow.
For men with mCRPC – which doesn’t respond to other therapies and is eventually fatal – survival rates are much worse, with patients only living for one to two years on average.
AstraZeneca executive vice president and cancer researcher, Jose´ Baselga, said: ‘For men with metastatic castration-resistant prostate cancer the disease remains deadly, especially in those who have failed on a new hormonal anticancer treatment.
‘This trial is the only positive Phase III trial of any [drug of this type] in metastatic castration-resistant prostate cancer, where the need for new, effective therapies is high.
‘We look forward to discussing these results with global health authorities soon.’