Biomedical Engineering Reference
In-Depth Information
who will be divided into four separate cohorts that will receive
different amounts of hESC-derived RPE cells injected just beneath
the retina (
http://www.clinicaltrials.gov
). Each patient will be
monitored before the next patient is treated and each cohort will be
followed up for four weeks before the next cohort is treated
(
http://www.clinicaltrials.gov
). Each patient will be monitored for a
total period of 12 months. As of mid-July 2011, two patients had
reportedly been treated at one of the trial sites in California
(Regalado). ACT has also received Orphan Drug designation for
Stargardt's macular dystrophy ('Press Release',
http://www.
advancedcell.com
, 2 October 2011).
The second ACT trial, for patients with advanced dry age-related
macular degeneration, is also reportedly recruiting now. Dry AMD is
a condition similar to Stargardt's macular dystrophy except it is not
known to be hereditary and is generally associated with ageing. The
dry AMD trial is recruiting patients over the age of 55, and will
follow a similar cohort structure to the Stargardt's macular dystrophy
trial (
http://www.clinicaltrials.gov
). Again, this is a safety trial, and
patients will be followed up for up to 12 months to assess the long-
term safety of the sub-retinal transplant of hESC-derived RPE cells.
A secondary endpoint in the dry AMD trial is to assess whether there
is any improvement in vision and what information this might reveal
about efficacy (
http://www.clinicaltrials.gov
). A secondary endpoint
in both trials is to explore how the grafts have developed and
integrated into the treated eyes (
http://www.clinicaltrials.gov
). As
with the Geron spinal-cord injury trial, the outcomes of the ACT
trials are keenly anticipated.
5.3 The future of hESC research?
Given the limited clinical successes of hESC research to date there is
clearly still a very long way to go before any products actually enter
the market. Outside of the technical achievements of hESC-derived
therapies, there are still a number of unanswered questions about the
safety and efficacy of hESC-based products that remain to be
