Why are Britain's health charities bent on sucking the blood from the NHS? The very same organisations that do such sterling work funding research, supporting patients and promoting awareness appear to have a blind spot when it comes to assessing what treatments are worth. We see it each time the National Institute for Health and Clinical Excellence (Nice) reaches an unpopular decision to ban a drug on the NHS because it is too expensive, as it did yesterday with the new prostate cancer medicine abiraterone. Cue uproar from charities.

"This decision is a bitter blow to thousands of men and their families and must be overturned," said Owen Sharp, the chief executive of the Prostate Cancer Charity. It was the same last month, when Nice ruled against three bowel cancer drugs. Mark Flannagan, the chief excecutive of Beating Bowel Cancer, said: "This is yet another blow for bowel cancer patients. All bowel cancer patients deserve the best care." Of course – how could anyone dispute that? Nice agreed that some of the drugs were effective – extending life by an average of 3.9 months in the case of prostate cancer. As Mr Sharp said, that could give a terminally ill man the chance to "walk his daughter down the aisle or see the birth of a grandchild". It is a disaster for such a man to be denied such a drug.

But we cannot provide every treatment that is effective to every patient who would benefit without regard to the cost. If we did, we would quickly bankrupt the NHS. Yet that is what the health charities are helping to do. By turning their fire on Nice, and neglecting the other player in the tragedy – the drug company involved – charities are effectively saying that protecting drug-company profits is more important than protecting the NHS.

Nice assesses each drug and calculates how much benefit it delivers for the cost. It mostly approves drugs costing up to £30,000 per Quality Adjusted Life Year (Qaly – a measure of the benefit), or for terminal conditions, up to £50,000. In this case, the prostate drug came in at £63,000 per Qaly, and the bowel cancer drugs at £110,000 per Qaly. So, in Nice's view, the drug companies Janssen and Amgen were charging more than they were worth. Did the health charities challenge the companies? No. Instead, they lambasted Nice. Do they receive drug company financial support? Perhaps we should be told.

Only Harpal Kumar, the chief executive of Cancer Research UK, struck the right note. Commenting on the prostate drug decision yesterday, he said: "We feel extremely let down that the drug's manufacturer couldn't offer Nice a price they could agree on." This is a £500bn global industry and it is time other organistations joined Nice in holding it to account to ensure fair prices are charged to the NHS.

j.laurance@independent.co.uk