WEDNESDAY, July 18, 2012 (HealthDay News) -- Taking vitamin B12 supplements may help boost the effectiveness of antiviral drugs for patients infected with hepatitis C virus, a new study suggests.
This effect was especially strong in patients whose infection was particularly tough to treat, note Italian researchers led by Dr. Gerardo Nardone of the University of Naples.
According to Nardone's team, the standard treatment of two drugs -- interferon (peg IFN) and ribavarin -- clears the virus in about 50 percent of patients infected with strain 1 of the virus and 80 percent of those infected with strains 2 or 3.
However, that means that the treatment still does not clear hepatitis C in about half of all patients infected with the virus or if the infection returns once treatment ends.
The new study included 94 patients with hepatitis C infection who were randomly assigned to receive standard treatment with antiviral drugs or standard treatment plus 5,000 micrograms of vitamin B12 every month for between six and 12 months.
The ability of the patients' bodies to clear the virus was assessed after one month and three months (dubbed a "rapid viral response"), at the end of treatment ("complete early viral response"), and six months after the end of treatment ("sustained viral response").
After one month of treatment, there was no difference in response between patients receiving standard treatment and those receiving standard treatment plus vitamin B12. However, patients receiving vitamin B12 showed significantly greater response at all of the other time points, particularly by six months after the end of treatment.
Overall, adding vitamin B12 to standard treatment strengthened the rate of long-term, sustained viral response by 34 percent, the researchers noted.
The investigators also found that the increased response associated with taking vitamin B12 was particularly strong in patients with the type 1 strain of hepatitis C and in those with higher levels of infection.
The addition of vitamin B12 to treatment with current antiviral drugs offers a safe and inexpensive option until new-generation antiviral drugs become available or if those new treatments are too expensive, the researchers concluded.
Two U.S. experts were more dubious as they weighed in on the findings.
Dr. David Bernstein is chief of the division of hepatology at North Shore University Hospital in Manhasset, N.Y. He noted that for patients with strains 2 and 3 of the virus, adding vitamin B12 "was not of any value."
As for patients with strain 1 of the virus, Bernstein said the standard of care is now a three-drug regimen of pegylated interferon plus ribavirin plus a protease inhibitor drug, not the two-drug regimen used in this study. So, "while the information presented in this study is interesting in genotype [strain] 1 patients . . . what would be more interesting would be the addition of vitamin B12 to the current standard of care therapy of pegylated interferon plus ribavirin plus a protease inhibitor," Bernstein said.
Dr. Peter Malet, director of the Center for Liver Diseases, and a hepatologist at Winthrop-University Hospital in Mineola, N.Y., agreed.
"This research is very preliminary; it needs to be confirmed or refuted by other studies," he said.
The study was published online July 17 in the journal Gut.
The U.S. National Institute of Allergy and Infectious Diseases has more about hepatitis C.