The Royal National Institute for the Blind clashed with the Government's watchdog on new medicines yesterday over a proposal to ration a sight-saving treatment.
The charity claimed thousands of people would go blind unnecessarily if the National Institute for Clinical Excellence (Nice) did not amend its proposal to limit availability of the treatment for age-related macular degeneration (AMD), the most common form of sight loss in Britain.
The treatment, photodynamic therapy, has been shown in trials to slow the progression of some kinds of wet macular degeneration. But in its appraisal, Nice notes that evidence is limited to two trials and the beneficial effect is greatest in wet AMD.
It also indicates that the treatment is costly at about £4m per 1,000 patients treated in the first year, rising to £8.3m in the third year.
AMD attacks the retina, destroying the central area leaving sufferers with only peripheral vision. It usually affects older people over 50. In the more common dry form, for which there is no treatment, cells in the retina stop working but in the more aggressive wet form, blood vessels grow behind the retina and tend to leak, causing damage including scarring.
Photodynamic therapy, developed in Britain, involves injecting a light-sensitive dye into the blood vessels, which is activated by a laser, blocking their growth and halting the disease.
In a preliminary ruling published yesterday, Nice proposed that the treatment should be restricted to the 2,500 people per year who develop classic wet AMD while for those with predominantly wet AMD – a larger group of 5,000 people – treatment should only be available as part of a clinical trial.
This follows a ruling in June that proposed limiting treatment to those who had lost their sight in one eye, although that recommendation was later withdrawn due to a lack of funding for research.
Steve Winyard, head of public policy at RNIB, said: "This recommendation beggars belief. In June, Nice said you have to go blind in one eye to get treatment for wet AMD, now they are saying you have to lose sight in both eyes."
Nice said yesterday it had not finalised its ruling and that the proposals were out for consultation until 4 November.