Sarah-Kate Templeton, Health Editor
BRITISH scientists have developed the world's first stem cell
therapy to cure the most common cause of blindness. Surgeons
predict it will become a routine, one-hour procedure that will be
generally available in six or seven years' time.
The treatment involves replacing a layer of degenerated cells with
new ones created from embryonic stem cells. It was pioneered by
scientists and surgeons from the Institute of Ophthalmology at
University College London and Moorfields eye hospital.
This week Pfizer, the world's largest pharmaceutical research
company, will announce its financial backing to bring the therapy
to patients.
The treatment will tackle age-related macular degeneration
(AMD), the most common cause of blindness. It affects more
than 500,000 Britons and the number is forecast to increase
significantly as people live longer. The disease involves the loss
of eye cells.
Under the new treatment, embryonic stem cells are transformed
into replicas of the missing cells. They are then placed on an
artificial membrane which is inserted in the back of the retina.
Tom Bremridge, chief executive of the Macular Disease Society,
said: "This is a huge step forward for patients. We are extremely
pleased that the big guns have become involved, because, once
this treatment is validated, it will be made available to a huge
volume of patients."
Embryonic stem cells have the ability to develop into all types of
body tissue. Their use is controversial, however, because it
involves the destruction of human embryos.
Laboratory trials completed by the British team have
demonstrated that stem cells can prevent blindness in rats with a
similar disease to AMD. They have also successfully tested
elements of the technology in pigs.
The team is led by Professor Pete Coffey, director of the London
Project to Cure Blindness, working alongside Lyndon da Cruz, a
surgeon at Moorfields.
Coffey said the treatment would take "less than an hour, so it
really could be considered as an outpatient procedure. We are
trying to get it out as a common therapy".
He welcomed Pfizer's agreement to manufacture the
membranes, saying: "This is a major development because of the
size of the partner. We need a big pharmaceutical company to
scale it up.
"We have nearly 14m people within Europe with AMD. This will
ensure that the therapy gets through to clinical trials in a safe and
effective manner."
Professor Peng Khaw, director of the Biomedical Research
Centre at Moorfields and the UCL Institute of Ophthalmology,
added: "This shows that stem cell therapy is coming of age. It
offers great hope for many sufferers around the world who
cannot be treated with conventional treatment." He added: "All my
patients say to me is, 'When will this stem cell treatment be
ready? I want it now'."
Pfizer's role would be crucial in bringing production of the
membranes to an industrial level.
The team is applying for regulatory approval for trials from the
Medicines and Healthcare products Regulatory Agency, the
Human Tissue Authority and the gene therapy advisory
committee.
The clinical trial, due within two years, is expected to be the
second in the world to use embryonic stem cells on humans. The
first, on patients with spinal cord injuries, will start this year in
America.
