New drugs on offer to fight the silent epidemic, hepatitis C
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 gruelling.
The new drugs, which could reach the market next year, could help subdue a virus that infects roughly four million Americans, most of them baby boomers, and 170 million people worldwide.
“I almost think this will be revolutionary, to be honest,” said Dr Fred Poordad, chief of hepatology at Cedars-Sinai Medical Centre in Los Angeles. “We are chomping at the bit to try to treat as many patients as we can.”
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.
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 per cent of patients, compared with 44 per cent of those treated with the existing drugs alone. And for many patients, the course of treatment could be halved to 24 weeks.
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 — a population that characteristically has little or no health insurance — who may not be the most able to stick to a lengthy treatment regimen that can cause brutal side effects.
Pharmaceutical companies “completely ignore the real face of hepatitis C,” said Dr Diana L Sylvestre, who runs a clinic in Oakland, 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, senior director of medical affairs, Vertex, said that addicts accounted for less than 10 per cent 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.
HIV and hepatitis C
Nevertheless, pharmaceutical companies realise that difficulties getting patients screened and treated could limit the use of their drugs. So they are contributing to a groundswell of activism to raise awareness of what has long been known as a ‘silent epidemic.’ Also contributing to the new advocacy is the highly organised HIV community, since 15 per cent to 30 per cent of those with HIV also have hepatitis C.
There is a risk that increased screening could result in treatment for people who will never need it. Only 5 per cent to 20 per cent of people with chronic infection develop cirrhosis in about 20 to 30 years, and doctors cannot predict which patients those will be.
“I think the companies have done a superb job of marketing this disease,” said Dr Ronald L Koretz, emeritus professor of clinical medicine, University of California, Los Angeles.
Koretz said there was no good evidence that treatment made a difference since many patients cured by the drugs might never have developed serious problems anyway.
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 HIV. 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.
The drugs could offer new hope to an estimated 3,00,000 people for whom the existing treatment has not worked. Some early data suggests that Telaprevir, when combined with the existing drugs, could cure half of them.