Vertex Pharmaceuticals Inc. on Tuesday said half of Hepatitis C patients taking a specific dose of its experimental drug in an early-stage trial tested negative for the virus 14 days after beginning treatment.

The tiny U.S. biotechnology company said the patients received a 750-milligram dose of its drug VX-950 every eight hours during the two-week phase I trial.

Results of the 34-patient study, which was conducted among patients with the hardest-to-treat genotype 1 strain of the virus, were presented at the annual Digestive Disease Week scientific meeting being held in Chicago.

“The big surprise is that half of patients in 14 days in this drug group went below levels of virus detection,” said Vertex Chief Executive Officer Joshua Boger.

By contrast, he said current two-drug treatments typically must be taken for three months before half of patients reach undetectable levels of the virus, and then must be taken another nine months to make sure the virus does not re-emerge.

“Our drug by itself appears to be dropping the virus to undetectable levels dramatically quicker than standard combination treatments,” Boger said, and without flu-like side effects.

Another patient in the Vertex-sponsored trial also tested negative for the virus after receiving a different dose of VX-950.

Detectable levels of hepatitis C returned in two of the five virus-negative patients a month after the Vertex trial concluded, but Boger said he is hopeful longer treatment in bigger future trials will prevent the virus from re-emerging after it is suppressed.

Consequently, he said several phase II trials that could begin late this year will last one to three months, testing the drug by itself and with at least one interferon used in current combo treatments sold by Schering-Plough Corp. and Roche Holding AG. .

“We believe it will take weeks or months to defeat the virus, and we’ll conduct the studies to find out,” said Boger, who noted that standard treatments last almost a full year.