A prostate drug hailed as a breakthrough in extending the lives of men with late-stage prostate cancer is too expensive for use on the NHS, a watchdog said today.
Leading cancer experts said the decision regarding abiraterone (also called Zytiga) was "disappointing" and a "huge blow" to patients with very few treatment options left.
Cancer Research UK said the draft decision by the National Institute for Health and Clinical Excellence (Nice) - which is still open to consultation - made "no sense" and Nice had used the wrong assessment criteria.
Abiraterone was developed by scientists at the Institute of Cancer Research (ICR) and the Royal Marsden in London after the discovery that some prostate cancers can produce their own testosterone.
It works in a new way, by blocking the production of male hormones in all tissues, not just the testes, including the adrenal glands and the tumours themselves.
A phase III trial, reported in the New England Journal of Medicine, involved 1,195 patients from 13 countries.
All had stopped responding to standard hormone therapies as well as second-line treatments such as chemotherapy drug docetaxil.
It showed that men survived an average of four months longer and suffered far less pain with abiraterone compared to those taking a placebo.
Although the average extended survival time was four months, some men did much better.
Abiraterone has been regarded as a "success story" for the ICR following more than two decades of work.
Nice has ruled that although abiraterone is clinically effective, it is not good value for money for the NHS at the price set by manufacturer, Janssen.
A spokeswoman for the ICR said: "We are obviously disappointed with this preliminary decision.
"We hope Nice will now work with the drug manufacturer to reach a solution that will make the drug more widely available to patients with advanced prostate cancer."
She said an estimated 10,500 men in the UK have advanced prostate cancer which is resistant to standard hormone treatments, adding: "Five new drugs have been shown in phase III testing to significantly extend life for men with advanced prostate cancer, and the ICR helped developed four of these, including abiraterone which was discovered at the ICR.
"None of these drugs are yet routinely available on the NHS."
Professor Peter Johnson, Cancer Research UK's chief clinician, said patients had been accessing abiraterone through the Cancer Drugs Fund, set up by the Government to pay for treatments not approved by Nice.
"This decision makes no sense," he said.
"Since it became available in the UK, abiraterone has been one of the most requested treatments from the Cancer Drugs Fund.
"This is because patients and doctors value the extra months of life it can give if prostate cancer has come back after chemotherapy.
"We need to find a way for it to be routinely available through the NHS.
"At the moment it is too expensive and Nice must find a better way to ensure drugs that are already working for patients get approved."
He said the Cancer Drugs Fund is only available until 2014 and applies in England, preventing patients in Wales, Scotland and Northern Ireland accessing it.
Prof Johnson also questioned Nice's methodology, saying it used its usual criteria - the total number of men who would benefit and the cost posed by the manufacturer.
But this decision should have only considered men who have the drug after chemotherapy, he said.
Because fewer than 7,000 men would be given abiraterone after chemotherapy, the drug should have been judged according to Nice's end-of-life drugs criteria.
Prof Johnson said: "Not only have Nice rejected an effective drug, they've also used the wrong criteria to judge its cost effectiveness.
"If they looked carefully at how many men would benefit, the overall cost could be more manageable than Nice's initial calculations indicated."
Nice insisted it had only considered men who would take the drug after chemotherapy which, based on information from the manufacturer, would leave 3,300 eligible for abiraterone.
The drug was not appraised under end-of-life criteria because it was not licensed for "a small population".
Chief executive Sir Andrew Dillon said one of the key benefits of abiraterone is that it can be taken orally at home.
He said Nice was "disappointed" not to be able to recommend it but added that the independent advisory committee "did not feel the drug provided enough benefit to patients to justify the price the NHS is being asked to pay, even with the discount that the manufacturer has offered".
Dr Harpal Kumar, chief executive at Cancer Research UK, said the draft decision had left the charity "hugely frustrated".
"Generous public donations to Cancer Research UK and other organisations paid for the initial development of the drug and we feel extremely let down that the drug's manufacturer couldn't offer Nice a price they could agree on."
Owen Sharp, chief executive of the Prostate Cancer Charity, said the draft decision was "a bitter blow to thousands of men and their families".
"The drug is one of the biggest breakthroughs in the treatment of the disease for many years, and it will be devastating if this drug remains out of their reach when they need it the most."
Data on another drug for late-stage prostate cancer, MDV3100, is being presented today at the American Society of Clinical Oncology Genitourinary Cancers Symposium in San Francisco.
It has been shown to extend lives by almost five months and was also developed with the help of experts at the ICR and Royal Marsden.
A further drug, cabazitaxel (Jevtana) was rejected by Nice in January following concerns about side-effects.
Each year around 37,000 men in the UK are diagnosed with prostate cancer and 10,000 die from the disease.