Goodbye, hepatitis C?
New UF-developed DNA nanotrain chugs through cancer cells
By Melissa Lutz Blouin
Hepatitis C patients may soon have effective new drugs that can clear the liver of the viral infection.
That’s good news for the population believed to be most affected by hepatitis C: the nation’s more than 70 million baby boomers — those born between 1945 and 1965.
UF professor of medicine David R. Nelson, M.D., and his colleagues reported the findings from two studies in The New England Journal of Medicine in April.
“This is the opening of the floodgates to change the treatment paradigms for this disease,” Nelson said. “It’s the beginning of the end for hepatitis C.”
Hepatitis C, a viral liver disease transmitted through contact with an infected person’s blood, can lead to liver problems including liver damage, cirrhosis, liver failure or liver cancer. Because a person with chronic hepatitis C can live symptom-free for years, many people do not know they are infected.
Globally, the World Health Organization estimates about 150 million people are chronically infected with hepatitis C, and more than 350,000 people die each year from related liver diseases. In the United States, estimates put the number of infected people between 3 million and 5 million.
The Centers for Disease Control and Prevention estimates that baby boomers account for about 2 million of those in the U.S. who are chronically infected with the disease. In August, the CDC released new guidelines that urged all baby boomers to get tested for hepatitis C, citing the disease’s prevalence, boomers’ lack of awareness of the disease and recent advances in treatment.
“This is a huge disease in terms of morbidity and mortality and health care costs,” Nelson said.
Until now, treatment for hepatitis C consisted of injections of interferon, a general immune stimulant that turns on the body’s defense mechanisms. However, at the high doses required to treat, interferon often creates toxic side effects, and more than two-thirds of hepatitis C patients cannot use the treatment regimen.
Nelson and colleagues conducted two randomized phase 3 trials, the final testing studies before a drug can be considered for approval. The studies, sponsored by Gilead, the maker of the drug sofosbuvir, were conducted with patients who had one of two types of chronic hepatitis C infection. In a trial called POSITRON, a group of 278 patients who could not take interferon took a combination of oral sofosbuvir and ribavirin or a placebo for 12 weeks. In a trial called FUSION, a group of 201 patients who had no response to prior interferon therapy took the drugs for 12 weeks or 16 weeks.
Sofosbuvir and ribivarin attack the virus itself, preventing it from replicating. Because the hepatitis C virus only lives and reproduces in the liver, the combination of antiviral compounds enables the body to eventually clear itself of the virus.
Viral reproduction was successfully suppressed during treatment for patients in both trials. The trials resulted in complete elimination of the virus in 78 percent of patients for whom interferon was not an option and for 50 percent to 73 percent of patients with prior treatment failure.
If the FDA approves this combination of drugs, they will be the first of their kind for the treatment of this disease.
More hepatitis C findings
In another study, a consortium led by UF and the University of North Carolina at Chapel Hill discovered that two other antiviral drugs used to treat hepatitis C work as well in real-world patients as they did during clinical trials. The international effort, known as HCV-TARGET, followed how newly approved therapies for hepatitis C — telaprevir and boceprevir — are used and managed in routine practice. — Claire Baralt