Thirteen Participants Treated in ACT's Stem Cell Clinical Trial
Results from the first-ever clinical trials of a
retinal disease treatment derived from stem cells continue to be
encouraging. Advanced Cell
Technology (ACT), developer of the therapy,
recently reported that 13 people — nine with Stargardt disease and
four with dry age-related macular degeneration (AMD) — have had no safety
issues after receiving transplanted cells. In addition, modest vision improvements for the first
participants treated more than a year ago have been sustained.
According to ACT, the transplanted cells — retinal pigment epithelial (RPE)
cells developed from human embryonic stem cells — appear to be engrafting into
the retinas of some of the participants. Engraftment is an indicator that the
transplanted cells have the potential to function like native cells.
RPE cells provide essential nutrition and waste removal for photoreceptors, the
cells that provide vision. The dysfunction of RPE cells in dry AMD and
Stargardt disease eventually leads to loss of photoreceptors.
The first nine participants in ACT’s trials each received transplants of 50,000
cells, and the next four received 100,000 cells. The researchers plan to
transplant as many as 200,000 cells for the treated retina of each patient
during their three Phase I/II clinical trials. Two studies — one for dry AMD, the other for
Stargardt disease —
are taking place in the United States. A trial for Stargardt disease is also
underway in the United Kingdom.
ACT’s researchers plan to treat people with less advanced disease in later
stages of their human studies. They believe the treatment may provide greater
vision improvement in these individuals.
The Foundation Fighting Blindness funded laboratory research that made ACT’s
human studies possible.