A drug for the asbestos-linked cancer mesothelioma has been blocked for widespread use by the NHS in England and Wales.
Mesothelioma most often attacks the lungs
The National Institute for Health and Clinical Excellence (NICE) decided Alimta should only be recommended for use in new or ongoing clinical trials.
NICE concluded there was not enough evidence the drug was better than cheaper treatments.
However, critics said some patients would be left worse off.
Professor Nick Thatcher, specialist lung consultant at the Christie Hospital NHS Trust in Manchester, said: "This decision, if upheld, will remove a very useful treatment option for patients with this resistant cancer.
"It is contrary to the scientific evidence and is purely based on the value Nice place on a person's life."
Mesothelioma is a type of cancer affecting the mesothelial cells, which cover the outer surface of most of the body's internal organs.
It most often affects the lining of the lungs and about nine out of 10 cases are linked to exposure to asbestos.
Although the use of asbestos was banned in the UK in 1999, it is predicted that 65,000 people will develop mesothelioma as a result of previous exposure.
There is no cure for the disease, but Alimta, known technically as pemetrexed disodium, is used to reduce symptoms. The drug costs about £8,000 for each patient.
Eli Lilly, which manufactures the drug, said it will appeal against the decision.
It said it will encourage the use of other, unlicensed treatments which have not been assessed for use.
Dr Joanna Nakielny, medical director of Lilly UK, said: "This is a major blow for patients with mesothelioma, many of whom were unwittingly exposed to asbestos in their working lives making submarines, ships, boilers and trains.
"This treatment does not save lives, but it can prolong the lives of patients and also improve the quality of the time they have left."