A draft decision not to make drugs for a leading cause of blindness widely available on the NHS will cost many people their sight, campaigners say.
AMD is the leading cause of sight loss in the UK
The National Institute for Health and Clinical Excellence (NICE) assessed treatments for age-related macular degeneration (AMD).
Its preliminary ruling is for a total block on one drug, Macugen, and tight restrictions on a second, Lucentis.
The ruling only applies to England and Wales.
Both drugs have been made widely available in Scotland.
But south of the border, NICE has recommended Lucentis be given only to people who have a specific type of the wet form of AMD - about 20% of the total.
Even then it is just recommended for patients with the condition in both eyes - and for use in the least diseased eye only.
Many go blind
AMD affects the macula - the central part of the retina at the back of the eye responsible for the vision necessary for everyday activities such as reading, driving and identifying faces.
The wet form of AMD is very aggressive and responsible for 90% of cases of blindness caused by the condition - more than 18,000 people a year in the UK.
It results in new blood vessels growing behind the retina, which are unstable and tend to leak fluid and blood, leading to scarring and sight loss.
Both Macugen and Lucentis, which are delivered by injection, are from a class known as anti-VEGF drugs, which work by targeting a protein that helps the formation of new blood vessels.
A study involving 716 people in the New England Journal of Medicine found Lucentis slowed vision loss in 90% of patients, and improved vision for about one-third.
Macugen costs about £10,000 a year, and Lucentis about £12,000.
Minority of patients
Andrew Dillon, NICE chief executive, said: "When treatments are very expensive, we have to use them where they give most benefit to patients.
"Most people with AMD only seek help once the disease is beginning to affect their second eye. Because of this, and based on the evidence they have seen, our independent advisory committee believes the right thing to do is to treat and try to save as much sight as possible in the better-seeing eye."
But Steve Winyard, of the Royal National Institute of Blind People (RNIB), said he was "outraged" by the guidance.
"It ignores the overwhelming body of evidence that these new treatments are cost-effective and have the potential to halve the number of people going blind each year," he said.
"It is simply unacceptable that only a small minority of patients within England and Wales will have access to these ground-breaking drugs.
"NICE must re-consider and show that it makes its decisions based on cost-effectiveness rather than simply cost containment."
Tom Bremridge, chief executive of the Macular Disease Society, said: "Limiting the treatment options to 20% of patients who would benefit is unjustifiable, and allowing one eye to go blind before treating the second eye is cruel and totally unacceptable."
Mr Winfried Amoaku, of the Royal College of Ophthalmologists, said it was wrong to limit treatment to people with a particular type of wet AMD when many others also faced blindness.
He also hit out at the decision to confine NHS patients to Lucentis.
"There are differences in action between these two drugs, which may be important in individual cases, and so we do not wish to be limited in our treatment options in this way."