Vertex hep C drug works well in twice daily dosing

* Twice daily telaprevir SVR rates of 82 pct and 83 pct

* Three times daily SVR rates of 81 pct and 85 pct

* 3 pct discontinuation rate due to rash

By Bill Berkrot

NEW YORK, Oct 31 (Reuters) - Vertex Pharmaceuticals Inc's (VRTX.O: Quote, Profile, Research) closely watched hepatitis C drug telaprevir proved nearly equally effective in a twice daily regimen as three times a day, knocking out the virus in more than 80 percent of patients in both groups in a small study.

All previous Phase II studies of the highly promising experimental drug tested the medicine at three times a day dosing given at eight-hour intervals. This study hoped to show telaprevir could be administered twice a day 12 hours apart, which would be more convenient for patients.

Patients who received telaprevir twice a day in combination with the standard treatments of pegylated-interferon and ribavirin had a sustained viral response (SVR) of 82 percent in one arm and 83 percent in another, depending on which brand of interferon they received.

That compared with 81 percent and 85 percent of patients who were given telaprevir in the three times daily regimen, according to data to be presented at the American Association for the Study of Liver Diseases (AASLD) meeting in Boston.

The percentage of patients in whom the virus is undetectable 24 weeks after completing treatment yields the critical measure known as sustained viral response, or SVR, which is considered tantamount to a cure.