WATANI International
15 August 2010
New medicines are being developed that are expected to transform the care of patients with hepatitis C, making treatment far more effective and far less grueling.
The new drugs, which could start reaching the market as early as next year, could help subdue a virus that infects 170 million people worldwide.
About two dozen pharmaceutical companies are now pursuing drugs for hepatitis C, which an executive at Vertex Pharmaceuticals recently called “one of the largest pharmaceutical opportunities this decade.”
That is because the toll of the disease, which now kills about 12,000 Americans a year, is expected to rise in the coming decade. Although new cases have dropped sharply, hundreds of thousands of people who were infected decades ago are expected to start experiencing the effects of liver damage.
New cases of liver cancer are already rising year by year. And hepatitis C is the leading cause of liver transplants.
Hopes for new treatments were buoyed in May by the first results from a late-stage clinical trial of one of the new drugs, telaprevir from Vertex. When added to the existing treatment — a combination of alpha interferon and ribavirin — telaprevir effectively cured 75% of patients, compared with 44% of those treated with the existing drugs alone. And for many patients, the course of treatment could be halved to 24 weeks.
Dr. Poordad, who is a consultant to some of the pharmaceutical companies, said that one-fifth of his patients were forgoing treatment now to wait for the new drugs.
But even if the drugs do work, some experts and doctors warn that this virus may be particularly tough to vanquish. Three-quarters of the people who are infected do not know it because they are not tested for the virus and because the infection can be asymptomatic for years while it stealthily attacks the liver.
And because this disease is transmitted by blood, those infected largely are former or current IV-drug users.
Pharmaceutical companies “completely ignore the real face of hepatitis C,” said Dr. Diana L. Sylvestre, who runs a clinic in Oakland, Calif., that treats drug addicts and former addicts with hepatitis C. “A minority of patients who have hepatitis C will benefit from these drugs.”
Dr. Camilla Graham, a senior director of medical affairs at Vertex, said that addicts accounted for less than 10% of people with hepatitis C. While many people got infected by trying drugs in the 1960s and 1970s, they have long since kicked the habit, she said.
Hepatitis C can also be transmitted sexually. And many people got the virus from blood transfusions before 1992, when donated blood began being tested for the virus.
Screening people for hepatitis C should become easier. In June, the Food and Drug Administration approved a rapid blood test developed by OraSure Technologies that gives an answer in 20 minutes rather than several hours needed if the sample is sent to a lab. Future versions might use a mouth swab, allowing screening to be done at churches, street fairs and other gatherings.
There is a risk that increased screening could result in treatment for people who will never need it. Only 5 to 20% of people with chronic infection develop cirrhosis in about 20 to 30 years, and doctors cannot predict which patients those will be.
The current treatment for hepatitis C consists of weekly injections of alpha interferon — the leading brands are Roche’s Pegasys and Merck’s PegIntron — combined with ribavirin, a generic oral drug. It is not quite clear how these drugs work.
The regimen usually lasts either 24 or 48 weeks and costs more than $30,000. It can be rough, causing flulike symptoms, depression, anemia and other problems. And the treatment fails to cure the patient about half the time, either because it cannot clear the virus from the body or because the patient cannot tolerate the drugs.
The new drugs generally inhibit enzymes needed by the virus, a strategy that has worked well against H.I.V. The two drugs that could conceivably make it to the market by next year, Vertex’s telaprevir and Merck’s boceprevir, are both pills that inhibit the protease enzyme.
For a few years at least, the new drugs would have to be used along with interferon. But doctors are hopeful that starting perhaps in five years, combinations of the new pills will do away with the need for interferon.
Some people with hemophilia, who were infected more than 25 years ago by blood-clotting drugs derived from human plasma, are pressing the Food and Drug Administration to allow them to be treated with combinations of the new drugs, without interferon, even before the new drugs are approved. The F.D.A. held a public hearing on the request in April and is now formulating a policy.
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The New York Times (abridged)