Analysis: Stem Cells Prevent Vision Loss

By STEVE MITCHELL

Advanced Cell Technology, the company that developed a technique for harvesting embryonic stem cells without harming the embryos, said Thursday it has shown human stem cells can prevent blindness in rats and plans to file an investigational new drug application to take the therapy into the clinic in 2007.

We’ve shown in this study you can use human embryonic stem cell-derived cells to restore visual function in animals that otherwise would’ve gone blind, Robert Lanza, Advanced Cell’s vice president of research and scientific development, told United Press International.

The stem cell therapy could have applications for macular degeneration, retinitis pigmentosa and other vision disorders, Lanza said.

Advanced Cell anticipates filing an IND with the Food and Drug Administration by the end of 2007, he said. The company has been in discussions with the agency and is currently developing a proposal that it plans to run by its consultants for their feedback.

Advanced Cell’s stock shot up more than 400 percent last month when it announced its biopsy technique for plucking a single cell from embryos that could give rise to an embryonic stem cell line while leaving the embryo unharmed.

The development, which was hailed as a way to make the promising research acceptable to those who oppose the destruction of embryos, erupted into a controversy over whether the embryos used in the experiment survived.

Lanza has vigorously defended the validity of the biopsy method and noted that two embryonic stem cell lines used in this latest experiment were generated using the technique.

Advanced Cell’s stock was up $0.05 to $0.80 in late-day trade Thursday.

Lanza said that so far the indications are that this latest technique used in the rats could be used to reliably generate the types of cells used in this study, retinal pigment epithelium. The eye may be an easier part of the body to transplant cells into because it is immunoprivileged and there are fewer problems with rejection. This opens the door for generating banks of these eye cells derived from human embryonic stem cells that could be transplanted into patients, he said.

In the study, which appears in the journal Cloning and Stem Cells, Lanza’s team generated dozens of lines of retinal pigment epithelium from 18 human embryonic stem cell lines. The cells were then injected into rat models of retinal disease.

We found that improvement in visual performance was 100 percent over untreated controls, Lanza said. He added that no adverse effects were detected.

Lanza said his company just finished another experiment with cells derived from human embryonic stem cells they are preparing for publication. This one involves an animal model of loss of blood flow in the legs.

Within a matter of days, after the cells were injected, they were restored to normal, he said. It’s pretty amazing stuff. People say embryonic stem cell research is being hyped but they have no idea.

Regina Cebula, an analyst with Decision Resources who recently authored a report about treatments for macular degeneration, told UPI stem cell therapies could eventually prove a valuable therapy for treating unmet needs in patients with this condition within the next 10 years.

In the future, as research supports the safety and efficaciousness, stem cell therapies will play a role in the treatment of disease, Cebula said. She noted physicians she interviewed are very excited by it.

Cebula said initially stem cell therapies will be reserved for select patient populations, such as those with declining visual acuity who are unresponsive to other therapies.

Another group that could benefit are bilateral late-stage AMD patients because they don’t have any real treatment options.

Visioncare Ophthalmic Technologies was developing an implantable miniature telescope for patients with this condition, but the company recently received a not approval letter from the FDA, she said.

One hurdle for companies focusing on stem cell therapies is reimbursement, particularly for a condition such as macular degeneration where most patients with this disorder are covered by Medicare. The Bush administration might be unlikely to cover treatments that are derived from embryonic stem cells, so reimbursement might become an issue if future administrations feel the same way, she said.

In the meantime, the macular degeneration field will be dominated by VEGF-inhibitors, with Genentech’s Lucentis replacing Novartis’ Visudyne as the leading treatment, Cebula said. She projected the market will grow to $1.8 billion by 2010 and $2.7 billion by 2015.