Vertex treatment for hepatitis C effective in trial

SAN FRANCISCO - Vertex Pharmaceuticals Inc., the developer of telaprevir for hepatitis C, said the experimental drug was able to kill the virus in 82 percent of patients in a study who weren't helped by standard treatments.

Telaprevir, an oral antiviral drug, eliminated the hepatitis C virus for four weeks in 49 of 60 patients who didn't respond to standard therapy, the Cambridge, Mass., company said yesterday. The drug's benefit appeared to be sustained after two and three months, researchers said.

When using the most sensitive test of virus in the blood, just 55 percent of telaprevir patients reached undetectable levels of virus after four weeks, which caused some investors to interpret the data as negative, said Geoffrey Porges, an analyst with Sanford Bernstein & Co. Porges.

"The data continues to suggest that telaprevir has the potential to offer real hope, and clinical and commercial benefit, to patients who have failed prior treatment, but investors are likely to react negatively to certain aspects of the data and incomplete prior disclosure," Porges said yesterday in a note to clients.

The data raise questions about how many patients will be free of the virus after six months, which is when they can be considered cured, he said.

Vertex shares fell $1.05, or 4.1 percent, to $24.90 in Nasdaq Stock Market composite trading. The stock has gained 7.2 percent this year.

About a third of patients are effectively treated with existing therapy, which takes a year and causes significant side effects, researchers said.

About 3 million people in the United States and 170 million worldwide have hepatitis C, according to Vertex.

The market for hepatitis C drugs may grow to $8 billion worldwide in 2015, said analyst Brian McCarthy with Merriman Curhan Ford & Co.

Detailed results from the study were slated for presentation yesterday at the Europe Association for the Study of the Liver in Milan.