UPDATE 1-Pharmasset: hepatitis C drug positive in early stage
(Adds analyst comments; updates stock movement)
By Esha Dey
BANGALORE, Aug 5 (Reuters) - Pharmasset Inc (VRUS.O) said preliminary results from an early-stage trial of its chronic hepatitis C treatment showed that the dosage tested had greater safety potential and could be carried forward into mid-stage studies, sending its shares up as much as 12 percent.
The data does not change the timeline of the drug, but implies a very high efficacy rate, analysts told Reuters.
The drug, R7128, was being tested for a 1,000 milligram, twice daily dose in combination with two current hepatitis C therapies, Pegasys and Copegus, in 31 treatment-naive patients chronically infected with hepatitis C virus.
Pegasys and Copegus are the current hepatitis C therapies of Roche (ROG.VX).
The drug, which is being developed in collaboration with Roche, was tested in two other early-stage trials for 500 mg and 1,500 mg doses. The drug showed potent short-term antiviral activity and was generally safe and well tolerated in those two trials.
Based on the latest results, the pharmaceutical company will now test the 1,000 mg dose in mid-stage trials, which are expected to be submitted to the U.S. health regulators this fall.
"This result indicates that it is unnecessary to carry the 1,500 mg dose forward, since the 1,000 mg dose may provide a greater margin of safety over longer treatment periods without sacrificing efficacy," Pharmasset's Chief Medical Officer Michelle Berrey said in a statement.
The 1,000 mg dose is lesser compared to other hepatitis C drugs being developed by competitors, and thus very favorable," Susquehanna Financial Group analyst Jason Kolbert said by phone.
Pharmasset competes with Schering-Plough Corp SGP.N and Vertex Pharmaceuticals Inc (VRTX.O), both of which have hepatitis C drugs in development.
"I think it is the best hepatitis C therapy out there, but it is still early in development and we need to keep that in mind," Liisa Bayko, an analyst with JMP Securities, told Reuters.
Shares of the company were up $2.12 at $24.13 in afternoon trade on Nasdaq. (Editing by Bernard Orr, Anil D'Silva)
