Adding the drug Zadaxin® to the standard therapy of pegylated interferon alpha and ribavirin produced a 61 percent early response rate in difficult-to-treat hepatitis C patients, according to researchers..
Zadaxin is a pure synthetic preparation of thymosin alpha 1, a substance that circulates in the blood naturally and is instrumental in the body's immune response to viral infections and certain cancers. The drug is currently the only non-interferon based new hepatitis C therapy in phase 3 clinical trials.
According to the researchers, the early success of Zadaxin in effectively treating in non-responders is significant since the dual therapy of pegylated interferon alpha plus ribavirin typically produces an early response rate of only 15 to 21 percent in non-responders.
Dr. Eduardo Martins, vice president of medical affairs of SciClone Pharmaceuticals, which is developing the drug, expressed hope that Zadaxin in combination with the other two drugs would be first therapy approved in the United States to specifically address the needs of non-responders.
The 12-week interim results from this triple therapy study were presented October 25 at the annual meeting of the American Association of the Study of Liver Disease in Boston.
Of the 23 study participants, 61 percent reported an early virologic response and 48 percent tested negative for HCV RNA. Of the 20 patients infected with the difficult-to-treat genotype 1 form of the virus, 60 percent reported an early virologic response and 50 percent tested negative for HCV RNA. No significant drug related side effects occurred.
During the course of this on-going trial, patients will receive 12 months of the triple therapy and will be observed for six months after completing therapy to measure sustained response.
SciClone Pharmaceuticals, Inc.