Assistant Managing Editor

While this year's European Association for the Study of the Liver meeting is filled with many familiar-sounding protease and polymerase inhibitors and nucleoside drugs that have crowded into the hepatitis C virus field of late, some of the most promising HCV data are coming from privately held GlobeImmune Inc.'s therapeutic vaccine.

The Louisville, Colo.-based firm reported final Phase IIb results for GI-5005, an active immunotherapy stemming from its Tarmogen-based platform, showing a 10 percent improvement in sustained virologic response (SVR). Data showed that GI-5005 boosted SVR in interferon-naïve, genotype 1 patients to 58 percent when given in combination with the pegylated interferon-plus-ribavirin standard-of-care regimen vs. 48 percent for patients receiving standard of care alone.

That's a 21 percent relative improvement, and it's the first time a therapeutic vaccine has shown that kind of efficacy in chronic HCV patients, trial investigator Ira M. Jacobson noted in a press release.

The study enrolled 140 patients who were either treatment-naïve or were nonresponders to standard of care. Additional data showed that adding GI-5005 resulted in a 67 percent relative improvement in the proportion of patients reaching normalized levels of ALT, a biomarker of liver injury. And a trend toward improvement was noted in biopsy necroinflammatory scores, with a relative improvement of 39 percent over patients receiving only standard of care.

Toxicity data were promising, too. GlobeImmune said the addition of GI-5005 did not increase the discontinuation rates due to adverse reactions compared to standard of care (13.2 percent for the GI-5005 group vs. 12.3 percent for the standard of care only arm), and the most common adverse events were "mild and transient" injection site reactions.

Over the weekend, the company is expected to report some much-anticipated pharmacogenomics data, demonstrating a correlation between the treatment effect of its HCV vaccine and polymorphisms in the IL-28 B gene.

GlobeImmune's platform is based on Tarmogens, short for Targeted Molecular Immunogens, whole recombinant Saccharomyces cerevisiae yeast that have been genetically modified to express more or one protein antigens. They are designed to fight disease by stimulating an immune response, sending killer T cells to infected cells.

Of course, in addition to GlobeImmune's vaccine, there were plenty of data emerging from some of the usual HCV candidates from the EASL conference in Vienna, Austria.

Shares of Cambridge, Mass.-based Idenix Pharmaceuticals Inc. got an 8 percent boost on interim data from a 14-day, Phase IIa trial showing that IDX184, its liver-targeted nucleotide prodrug of 2'-methl guanosine monophosphate, demonstrated dose-dependent antiviral activity when given in combination with peginterferon and ribavirin. At day 14, mean viral load reductions were 4.2 log10 for the 100 mg, once-a-day treatment group; 4.0 log10 for the 50 mg, twice-a-day group; 2.7 for the 50 mg once-a-day group; and 1.2 log10 for the placebo group.

Half of patients receiving a daily dose of 100 mg of IDX184 achieved undetectable virus levels by the end of the trial.

Idenix's stock (NASDAQ:IDIX) gained 33 cents to close Thursday at $4.41.

Pharmasset Inc., of Princeton, N.J., which is developing nucleoside analogue PSI-7977, saw its shares (NASDAQ:VRUS) jump $2.34, or 8 percent, to close at $31.20, on interim data from a 28-day study of the drug in combination with peginterferon and ribavirin in previously untreated patients. A total of 38 patients have completed therapy. Of those, eight of 10 receiving 100 mg once daily, nine of nine patients receiving 200 mg once daily and 10 of 11 patients receiving 400 mg once daily have achieved a rapid virologic response.

Full data from all 63 patients in that trial are expected later this quarter.

Developing a polymerase inhibitor for HCV, Anadys Pharmaceuticals Inc. said data from an ongoing Phase II study showed that 72 percent of patients treated with ANA598 plus standard of care reached undetectable levels of virus at week eight compared to 38 percent of patients getting placebo plus standard of care. The San Diego-based firm said the adverse event profile was comparable to standard of care, and added that none of the patients experienced viral breakthrough while on ANA598.

Shares of Anadys (NASDAQ:ANDS) rose 9 cents to close Thursday at $2.70.

In the protease inhibitor space, Vertex Pharmaceuticals Inc., of Cambridge, Mass., reported data from a Phase II rollover study involving patients who had been in the control pegylated interferon and ribavirin arm of the PROVE trials who did not achieve SVR. In the open-label study, dubbed Study 107, 59 percent of those patients overall who received a telaprevir-based combination regimen achieved SVR. Fifty-six of prior treatment null responders reached SVR after 48 weeks, while 97 percent of prior treatment relapsers and 55 percent of prior treatment partial responders hit SVR after a 24-week or 48-week telaprevir-based regimen.

Brisbane, Calif.-based InterMune Inc. presented results from a 15-day, Phase Ib study testing low doses of its protease inhibitor, danoprevir (RG7227/ITMN-191), boosted by low-dose ritonavir. Data showed that 18 of 25 patients (72 percent) had HCV RNA levels below the limit of detection, and no patient experienced virologic rebound in any dosage group.

And a protease inhibitor, ACH-1625, from New Haven, Conn.-based Achillion Pharmaceuticals Inc. resulted in a significant reduction in HCV RNA after five days of monotherapy treatment in patients in an ongoing Phase I trial. The drug also showed sustained viral suppression in HCV patients for at least seven days after dosing was completed.

In other EASL news:

• Biolex Therapeutics Inc., of Pittsboro, N.C., and OctoPlus NV, of Leiden, the Netherlands, reported interim results after 36 weeks of treatment from its Phase IIb SELECT-2 trial, showing that Locteron dosed every other week demonstrated comparable reduction in viral load vs. the weekly dosed standard of care, while achieving a 65 percent reduction in flu-like adverse events. Locteron is a controlled-release formulation of interferon-alpha. OctoPlus licensed rights to the drug to Biolex in 2008.

• Idera Pharmaceuticals Inc., of Cambridge, Mass., reported interim data from a Phase I trial of IMO-2125, a Toll-like receptor 9 agonist, in null responder chronic HCV patients. Data showed that the drug was well tolerated through the first four dose levels, and patients receiving IMO-2125 exhibited dose-dependent increases in endogenous interferon-alpha and other antiviral proteins. Serum concentrations of induced interferon-alpha also correlated with decreases in HCV viral load, and six of eight patients who received IMO-2125 at 0.32 mg/kg/week showed the maximum viral load reductions, ranging from 1 to 3.5 logs at least once during the treatment period.

• Romark Laboratories LC, of Tampa, Fla., said results from a Phase II study of nitazoxanide in treatment-naïve, genotype 1 chronic HCV patients showed that 12 weeks after the end of treatment, 44 percent of patients treated with the drug in combination with standard of care achieved SVR vs. 32 percent of patients receiving standard of care alone plus placebo. Rates were consistently higher in subsets of patients with high baseline viral load (41 percent vs. 29 percent) and in African-Americans (38 percent vs. 20 percent). Final results from the trial are expected in May.

• Scynexis Inc., of Research Triangle Park, N.C., reported data demonstrating that HCV required multiple mutations across two separate proteins in order to establish resistance to its oral, cyclophilin inhibitor, SCY-635. Those data were based on an in-depth analysis of samples of plasma virus from individuals who participated in the company's Phase Ib study.