When interferon injections -- the current standard treatment -- work, which only happens about 16 percent of the time, the risk of dying drops by 45 percent, the University of Southern California researchers said. Unfortunately, the drug doesn't always manage to suppress the virus completely and many people can't tolerate its side effects, which include gastrointestinal problems and anemia.
"This study points out the inadequacies of old therapies for hepatitis C," said Dr. Douglas Dieterich, a professor of medicine and liver diseases at the Icahn School of Medicine at Mount Sinai Hospital in New York City.
Hepatitis C is a viral infection that causes inflammation of the liver. It's transmitted from person to person via blood.
Liver specialists said that although this study may be reflective of what's currently going on in hepatitis C treatment, soon there will be a huge shift in the way the disease is treated.
"There's a revolution afoot in the treatment of hepatitis C," Dieterich said. He said new treatments that are taken in pill form should be approved in the coming months, and the newer medications will be far more effective at treating hepatitis C than interferon. He added that the treatment times also will be shorter.
"By the fourth quarter of next year, we'll have at least two new drug cocktails, curing upwards of 90 percent of patients -- even those with cirrhosis," he said.
Dr. David Bernstein, chief of the division of hepatology at North Shore University Hospital in Manhasset, N.Y., said the new treatment options are "exciting, but we need to remain somewhat skeptical because many of the studies were done on small groups."
Most people who have hepatitis C don't have any symptoms, and can go years without knowing they have the virus.
"The bulk of people with hepatitis C were born between 1945 and 1965, and more than three-quarters of those infected don't know they have it," said Dr. Paul Gaglio, medical director of the Montefiore Einstein Center for Transplantation, in New York City.
The current study included more than 360,000 U.S. military veterans who'd been diagnosed with hepatitis C. Ninety-seven percent were male, and their average age was 52. More than half were white and almost one-third were black.
Only 24 percent of the veterans chose to receive treatment for their hepatitis C. Of those who received treatment, just 16.4 percent achieved undetectable levels of the virus in their blood. That likely means that many of the study volunteers may have stopped taking the medication before the recommended 48 weeks of treatment was finished, Bernstein said.
The good news was that when the treatment did work, the risk of dying from any cause dropped by 45 percent.
"This study is indicative of standard practice now," Gaglio said. "Patients don't want to take the treatment because there are lots of side effects. But big changes are coming."
Bernstein said three new treatment regimens likely will be approved by the U.S. Food and Drug Administration in December, and another round of approvals likely will occur in late 2014 or early 2015.
All three experts said the message for people with hepatitis C is to go back to their doctor and get re-evaluated. New treatment options will soon be available, and they'll be available for folks with kidney disease and cirrhosis of the liver.
"The treatment world is really changing," Bernstein said.
Gaglio added that if you were born between 1945 and 1965 and you haven't been tested for hepatitis C, it's important to get tested to ensure that you aren't infected with the virus.
The study was published online Nov. 5 in the journal JAMA Internal Medicine.
Learn more about hepatitis C from the U.S. National Library of Medicine.