Industry

Nucleotide polymerase inhibitor for hepatitis C moves ahead

Last Updated: 2011-11-04 18:50:18 -0400 (Reuters Health)

By Esha Dey

(Reuters) - Inhibitex Inc's experimental hepatitis C medication showed promise in a clinical trial, making the company a frontline player in the race to develop a new class of drugs that could potentially be worth several billion dollars.

Inhibitex's INX-189 belongs to a promising class of hepatitis C drugs called nucleotide polymerase inhibitors, which target an enzyme essential for replication of the hepatitis C virus.

However, most hepatitis C drugs used today are combination therapies, and a monotherapy like Inhibitex's drug could be a game changer for patients and physicians.

"This data supports the power of nucleotide drugs for treatment of hepatitis C and positions the company well as one of only three companies developing such scarce assets," Canaccord Genuity analyst George Farmer said.

The other two companies developing nucleotide drugs for hepatitis C are Pharmasset Inc and Idenix Pharmaceuticals Inc.

Earlier this week, Pharmasset said it started a phase III trial of its drug, while Idenix's drug is currently in phase II studies.

Inhibitex said the mid-stage trial showed INX-189 had potent and dose-dependent antiviral activity and had a median 4.25 log viral load reduction.

"This compares favorably to the 4.5 log drop observed with (Pharmasset's) PSI-7977 in a similar treatment setting," Canaccord's Farmer said.

Inhibitex's study tested INX-189 on its own, and in combination with ribavirin, for seven days in chronic hepatitis C patients who have not received any other treatment.

The 200 mg dose of the drug, given once daily for seven days, continued to show potent and dose-dependent antiviral activity, the company said in a statement. The dose was generally well tolerated and there were no serious adverse events, or dose-dependent adverse events observed.

The nucleotide drugs would pose the biggest threat to Vertex Pharmaceuticals Inc's Incivek (telaprevir) and Merck & Co's Victrelis (boceprevir), both of which got approval earlier this year.

Incivek won U.S. approval in May, and by July was reported to have garnered blockbuster sales. Victrelis, which was given the nod in May, is also expected to hit sales of over $1 billion.

The market for hepatitis C treatments is expected to be worth around $15 billion by 2019.