TUESDAY, May 5, 2015 (HealthDay News) -- Researchers have released yet another study finding impressive results for an experimental drug combo that aims to rid the body of infection with liver-damaging hepatitis C.
In this case, a combination of three drugs in the pipeline -- daclatasvir, asunaprevir and beclabuvir -- effectively cleared the virus in 93 percent of patients, according to new research from Duke University in Durham, N.C. All of the patients had already developed an infection-linked scarring of the liver known as cirrhosis.
None of these drugs has been approved by the U.S. Food and Drug Administration, but daclatasvir is currently under FDA review, according to a Duke news release.
One U.S. expert said the drug combination could be an additional advance against hepatitis C.
"This regimen is yet another all-oral treatment for the most common type of hepatitis C, which offers high cure rates with what appears to be an excellent tolerability profile," said Dr. David Bernstein, chief of the division of hepatology at North Shore University Hospital in Manhasset, N.Y.
The study is published in the May 5 issue of the Journal of the American Medical Association.
As the researchers noted, for the past two decades treatment for hepatitis C has largely relied on interferon drugs, involving regular injections. The treatment, which can last for up to a year, is associated with severe flu-like symptoms, and many people discontinue the medication due to these unwanted side effects. Other patients are not able to take interferon because they are anemic, have a low platelet count or have another health issue.
The new study's lead author explained: "Those with more advanced disease were unlikely to tolerate interferons, and many patients would decide against even getting treatment," said Dr. Andrew Muir, chief of the division of gastroenterology at Duke. "For those who could tolerate it, it was only moderately effective," he said in the news release.
However, since 2013, several drug companies have released new hepatitis C treatments that do not involve interferon drugs such as Sovaldi (sofosbuvir) or Harvoni (lepdipasvir-sofosbuvir). While very expensive, these drugs have also been very effective in safely ridding the body of hepatitis C.
"The development of interferon-free treatments has been a tremendous step forward in the standard of care," Muir said. "These drugs are highly effective and well-tolerated by patients at all stages of liver disease."
The new study was funded by drug maker Bristol-Myers Squibb. It involved 112 patients with cirrhosis related to hepatitis C that were never treated, as well as 90 who had undergone unsuccessful treatment for the condition.
The patients were treated between December 2013 and September 2014 at nearly 50 locations across the United States, Canada, France and Australia. All of the participants had genotype 1 hepatitis -- a common strain of the hepatitis C virus in North America, Western Europe and Australia.
The three-drug regimen cleared the virus in 93 percent of patients with cirrhosis, according to a new study. The patients who benefited from the 12-week dose of three different drugs hadn't received any previous treatment, the study's authors noted.
The researchers found the drugs were less effective for those who'd been treated unsuccessfully in the past. The combination treatment eliminated the virus in 87 percent of these patients, suggesting their disease could be resistant to treatment.
Therapy was slightly more effective however, when these patients were given a fourth drug, ribavirin, which is commonly used to treat hepatitis C. After taking the additional drug, success rates jumped to 93 percent, according to the study.
Most of the patients had minor side effects. Nine of them developed serious health issues, but just three were considered related to the treatment.
The study had some limitations. First, there was no control group that could help the researchers identify the source of the side effects. The study also lacked racial diversity, since 88 percent of the participants were white.
And Bernstein also added that with highly effective drugs like Sovaldi and Harvoni already available, "it is unclear what advantage this potential regimen adds to the currently available hepatitis C treatments."
Experts note that there is currently no vaccine to protect against hepatitis C. The virus spreads through the blood. If left untreated, it can lead to liver failure and death.
Many people with hepatitis C however do not even know that they are infected until they develop symptoms and liver damage, the study's authors said. They advise all Americans born between 1945 and 1965 to be screened for the virus.
The U.S. Centers for Disease Control and Prevention provides more information on hepatitis C.