Patients with macular degeneration must rely on pricier of two drugs

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Jan Ross would be quickly losing her vision if not for eye injections of a medication designed to stave off the effects of macular degeneration, the leading cause of blindness in older people.

Ms. Ross, a 72-year-old Toronto resident, is one of many Canadians being treated with ranibizumab, a highly effective, but expensive, drug sold under the brand name Lucentis for treatment of the "wet" form of age-related macular degeneration, or AMD. The provincial government pays for Ms. Ross's treatment, which costs $1,600 or more for monthly injections.

What Ms. Ross didn't realize is that she could have been receiving a similar treatment called bevacizumab sold under the brand name Avastin, and that it would only cost about $50 per injection.

"I'd be happier if a cheaper one could be used," Ms. Ross said. "I know it's a tremendous amount of money for the health care [system]to pay for me."

It seems patients will continue to be treated with the more expensive drug, despite mounting evidence that the cheaper version works just as well.

The issue reached a boiling point in April when the New England Journal of Medicine published results from a comprehensive "head-to-head" trial of the drugs, which found they are equally effective. Although the study left lingering questions about whether Avastin is as safe as Lucentis, researchers are hoping to provide answers in future studies.

Despite the fact Avastin has been shown in clinical trials to be as effective as the pricey Lucentis, it's not covered by any health plan in Canada. It's also not approved by Health Canada to be used as a treatment against the wet form of macular degeneration.

In order for a drug to be approved by the federal government and included in provincial drug-coverage plans, the drug maker must submit an application to Health Canada.

Roche, which sells Avastin in Canada, appears to have no intention of getting the drug approved as a macular-degeneration treatment here. The company also sells the much pricier Lucentis in the United States and licensed Novartis to sell it in Canada and elsewhere in the world. Both could lose a substantial amount of money if cheaper drugs are made available.

Critics say the situation highlights deep flaws in the way research is funded and the influence drug-makers can have over health-policy decisions.

"[The company]is actively working in order to discredit or put obstacles for doctors to prescribe Avastin [to treat]AMD," said Marc-André Gagnon, assistant professor in the School of Public Policy and Administration at Carleton University and research fellow at the Edmond J. Safra Center for Ethics at Harvard University. "The bottom line ... is that we need to support more public research to have real clinical trials comparing drugs."

AMD causes sharp central vision to deteriorate from the abnormal growth and leakage of blood vessels in the macula, which is in the centre of the retina and is responsible for best visual acuity. CNIB, formerly known as the Canadian National Institute for the Blind, estimates that one million Canadians have some form of AMD.

The "wet" form of the disease is considered the most serious and can cause faster vision loss. New blood vessels form to improve the blood supply to the retinal tissue, but they are fragile and break easily, which can cause bleeding and damage to surrounding tissue.

In the past, treatment options for wet-AMD were limited.

But the development of Lucentis and Avastin is changing that. The two drugs are known as anti-vascular endothelial growth-factor treatments and they help inhibit growth of potentially damaging blood cells when they are injected into the eyes.

The two drugs, both developed by Genentech, are derived from the same mouse monoclonal antibody. The only major difference is that Lucentis has smaller molecules specially designed to treat eye diseases.

The debate has been simmering for several years but was reignited with the publication of the New England Journal of Medicine study.

"Health-care providers and payers worldwide will now have to justify the cost of using ranibizumab [Lucentis]" wrote Philip Rosenfeld, an ophthalmologist at the Bascom Palmer Eye Institute of the University of Miami School of Medicine, one of the world's top centres, in an editorial published with the study.

So far, Canadian provinces aren't jumping into the debate. For instance, Ontario and Manitoba, which both cover Lucentis under their drug programs, said they are not considering the issue and will continue to fund the more expensive drug.

Advocacy groups such as CNIB, which accepts funding from drug companies including Novartis, also said it's not interested in urging governments to cover Avastin along with or instead of Lucentis.

Novartis highlighted that the study results left many unanswered questions about the safety of Avastin. The company also pointed to a second study published by Johns Hopkins University, which found strokes and death were higher among patients taking Avastin than those taking Lucentis. That study was funded by Genentech, a subsidiary of Roche which manufactures both drugs.

"Now more than ever it is clear that Lucentis and Avastin are different, and Novartis believes Lucentis is the best treatment option for patients with wet AMD," said Trevor Mundel, global head of development at Novartis, in a statement.

Yet researchers say the safety differences appear small and are perhaps even unrelated to the treatment itself, although the likelihood of serious side effects with Avastin are not yet well understood.

"There were other complications which were not related to the drugs … which seem to [have occurred]more in the Avastin group than the Lucentis group," said Suresh Chandra, professor of ophthalmology at the University of Wisconsin School of Medicine and Public Health. "Most people believe that is really not related to the drug, it's just a coincidence, but we really can't prove [it]"

To Joel Lexchin, professor in the School of Health Policy and Management at York University in Toronto, the case demonstrates the power that drug companies have over health-policy decisions.

"It's not a question that Lucentis is a bad drug," Dr. Lexchin said. "It works. It's good. It's just economic exploitation."