Macular degeneration is the leading cause of blindness in people aged 50 and older. The major finding comes from two clinical trials reported in the Oct. 5 issue of The New England Journal of Medicine.
David M. Brown, MD, a retina surgeon at Houston's Methodist Hospital, was a researcher for one study. Philip J. Rosenfeld MD, PhD, of the University of Miami's Bascom Palmer Eye Institute, was a researcher for the other.
"It is truly better than our greatest expectations," Brown tells WebMD. "The biggest advance from both trials is they are the first ever to show significant improvement in vision."
"This is not a cure," Rosenfeld tells WebMD. "If macular degeneration patients have lost vision for a year or longer, this is not going to restore their vision. But for the right patients, at the right point in their disease, these drugs are extremely beneficial."
Lucentis is expensive. The wholesale cost is $2,000 a dose. But Brown says there are different ways to look at this cost.
"I have a patient, a farmer with one eye, who was 96 when he started the study and is 99 now -- still driving his tractor and still taking care of his cows," Brown says. "They talk about the cost of this drug. But the cost of not being able to drive and losing your job and being put in assisted living -- that is the true cost."
Lucentis and Avastin
While the Brown and Rosenfeld studies focused on Lucentis, they have implications for a drug that wasn't being tested: Avastin.
Lucentis and Avastin work by exactly the same mechanism. Both are antibody-based drugs that block the chemical messenger -- vascular endothelial growth factor A or VEGF-A -- that tells new blood vessels to grow.
In cancer, Avastin keeps tumors from growing the blood vessels they need to survive. In wet , Lucentis stops the inappropriate growth of blood vessels that leak fluid and displace the retina.
Avastin is a whole anti-VEGF antibody, designed for infusion into the bloodstream. Lucentis is the active fragment of the antibody, specifically formulated for injection into the eye. Before Lucentis became available, Rosenfeld and others pioneered the use of eye injections of Avastin to treat wet macular degeneration.
"I have examples where some patients respond better to Avastin and some respond better to Lucentis. Not everyone is the same," Rosenfeld says. "We wonder if Avastin is safe if used long term. And is it as effective as Lucentis? This week we learned the National Eye Institute has funded a study to compare the two, so we will have a multicenter trial to compare the two drugs."
Still, the cost of Lucentis contributes to worries about the rising cost of health care.
"Eighty-one percent of patients eligible for Lucentis treatment have enough insurance -- supplemental insurance or private insurance -- to bring their copay down to $50 or less," Genentech spokeswoman Dawn Kalmar tells WebMD. "About 3% of patients are uninsured. They are good candidates for our free drug program. We are committed to all patients having access to our drugs, regardless of their ability to pay."
Lucentis: New Standard of Care
The two trials differed in their approach. The study that included Rosenfeld looked at 716 patients with what doctors call "occult" macular degeneration. That's a less-aggressive form of the disease, in which blood-vessel leakage in the eye tends to be less intense and to occur later in the course of the disease.
Patients in this study received two different doses of Lucentis or sham injections every month for two years. About 38% of patients who received sham injections had significant vision loss over the course of one year. Only about 5% of the patients treated with Lucentis had significant vision loss.
On the other hand, more than a third of patients treated with the standard dose of Lucentis -- but only 5% of sham-treated patients -- had significant vision improvement. This benefit continued throughout the second year of the study.
The results were even more striking in the study done by Brown. This study looked at 423 patients with the "classic" form of wet macular degeneration, in which blood-vessel leakage is more severe and leads to rapid loss of sight.
A third of the patients received standard "photodynamic" therapy. In this treatment, a drug that makes tissues more sensitive to light -- Visudyne -- is injected into the unwanted blood vessels in the eye. The eye is then treated with a laser that off the light-sensitized tissues.
The other two-thirds of the patients received different doses of Lucentis plus sham photodynamic therapy.
The results were similar to those seen in the Rosenfeld study. More than a third of the patients given standard photodynamic therapy had vision loss, and fewer than 6% had improved vision. At the standard dose of Lucentis, fewer than 3% of patients had vision loss -- but more than 40% had improved vision.
The researchers were relieved to find that very few Lucentis patients developed eye infections. There was also no increase in serious adverse events occurring outside the eye -- such as or -- although the studies weren't big enough to detect relatively rare side effects.
Lucentis is injected directly into the eye. Currently, the drug is supposed to be given every month for the rest of a patient's life. But Brown and Rosenfeld agree that not all patients need such frequent treatment. Brown says he's finding that most patients need six injections the first year, four the next, and injections as needed after that.
What about patients who already have significant vision loss?
"We don't know the answer for long-lasting age-related macular degeneration," Brown says. "We are seeing those patients and doing clinical exams."