June 17, 2011

Stem Cell Trials To Begin For Blindness Treatment

The first two patients with common but incurable diseases of the eye that can lead to blindness have been enrolled early in a two phase groundbreaking clinical trial of therapy that researchers are hoping will heal the damage caused by the conditions.

Advanced Cell Technology Inc. (ACT) announced Thursday the enrollment of the patients in the trials for Stargardt's Macular Dystrophy (SMD) and Dry Age-Related Macular Degeneration (Dry AMD). The patients were enrolled at the Jules Stein Eye Institute at the University of California, Los Angeles.

ACT won approval by the US Food and Drug Administration in January to use human embryonic stem cells for treating macular degeneration, a common cause of vision loss. That followed FDA approval in November for scientists to test the stem cells to treat people with Stargardt's Macular Dystrophy. The new trials will test the safety and tolerability of retinal pigment epithelial, or RPE cells, which ACT makes from the human embryonic stem cells.

"The enrollment of the first patients in our two clinical trials marks an important step forward for the field of regenerative medicine," said Gary Rabin, interim chairman and CEO of ACT. "We are very pleased with the progress that has been made toward bringing this ground-breaking technology to the patients who need it most."

A total of 24 patients have entered the two separate trials, said representatives from the Massachusetts-based ACT. Starting in July, the remaining 22 participants will be officially enrolled into the study, according to a company spokeswoman.

The medical team hopes to slow, halt or even reverse the effects of the conditions by injecting the healthy RPE cells into the eye.

"These trials mark a significant step toward addressing what is one of the largest unmet medical needs of our time, treatments for otherwise untreatable and common forms of legal blindness," lead investigator Steven Schwartz at University of California Los Angeles Jules Stein Eye Institute, told AFP.

Each of the two studies will have 12 patients, with groups of three testing different doses of the RPE cells. Dr. Robert Lanza, chief scientific officer of ACT, said in an email that the company planned to start stem cell transplants within the next few weeks.

"After a decade of extensive research and preclinical studies, it is very satisfying to finally be moving into the clinic," Lanza told Reuters in a statement. "We hope that these cells will, in the future, provide a treatment not only for these two untreatable diseases -- Stargardt's disease and macular degeneration -- but for patients suffering from a range other debilitating eye diseases."

Dry AMD is the most common form of macular degeneration and the leading cause of blindness in the developed world, according to Dr. Schwartz. The number of cases is expected to double over the next 20 years as the population ages, he said.

Currently, there is no cure for AMD, which affects more than 10 million Americans and another 10 million in Europe, ACT said.

Stargardt's disease causes blindness by destroying the pigmented layer of the retina. After that follows degradation of photoreceptors, which are the cells in the retina that detect light. Patients with Stargardt's often experience blurred vision, difficulty seeing in low-light conditions and eventually most lose their ability to see at all. The disease can be inherited by a child when both parents carry the gene mutation that causes it.

The trails announcement is a milestone for ACT, which has been developing the therapy for the past decade.

The first trial will be given to patients with dry AMD. The second focuses on Stargardt's, which generally strikes younger people between the ages of 10 and 20. The early-stage trials will be assessed by doctors over a 12-month period.

If the treatment works as well as doctors hope, the injected RPE cells will grow and eventually restore the retina to a healthy state able to support light-sensitive cells required for eyesight.

"We hope that these cells will, in the future, provide a treatment not only for these two untreatable diseases, Stargardt's disease and macular degeneration, but for patients suffering from a range of other debilitating eye diseases," Lanza told the Guardian.

"If these therapies work as we hope they will, particularly with small volumes of cells, then we should be in an excellent position to take advantage of our patented techniques for manufacturing large numbers of doses of RPE cells that can be conveniently stored and shipped to clinicians following the basic manufacturing and distribution systems already familiar to pharmaceutical and biotech companies," Rabin said.

Animal studies have reportedly shown that injecting fresh RPE cells into the eye could bring about a substantial improvement in eyesight. In other studies, scientists said mice with eye disease recovered near-normal vision after receiving the therapy.

Geron Corp last October enrolled its first patient in an approved study of human embryonic stem cells with the goal of treating people with spinal cord injuries.

Scientists around the world hope to be able to use the stem cells to address not only spinal cord injuries and eye diseases, but also for cancer, diabetes, Alzheimer's and Parkinson's diseases.

Opponents of human embryonic stem cell research object to their use because in order to get the cells, someone has to take apart a human embryo. The Obama administration last year overturned the strictest limitations on using federal funds for the research, but the policy was challenged by two researchers. In April, a US appeals court ruled that funding can continue.

In addition to the Jules Stein Eye Institute at UCLA, the Casey Eye Institute (CEI) at Oregon Health & Science University (OHSU) in Portland, OR, is also open for enrollment of patients with SMD.

As additional sites are ready to enroll patients with SMD and dry AMD, they will be listed on the Clinical Trials page on ACT's Web site and at http://www.clinicaltrials.gov.