Vicrivirox works better than older drugs in holding back virus, study shows; IDX899 provides “‘rapid, profound’ inhibition of HIV replication
Bloomberg News reported this week that Schering-Plough Corp.’s new AIDS drug, designed to block the virus from entering human cells, suppressed infections in patients who don’t respond to older medicines.
The study, sponsored by Schering-Plough Corp., showed that a drug combination including the company’s vicriviroc was better at holding back the virus than the combination of older medicines alone.
Findings were presented at the Conference on Retroviruses and Opportunistic Infections this week in Boston.
Vicriviroc, like Pfizer’s drug Selzentry, works by altering the shape of a protein on the surface of healthy human cells, making it impossible for HIV to get a good enough grip to enter.
Bloomberg News reported that in a 48-week study, 56 percent of patients on a 30 milligram dose of vicriviroc combined with older drugs had the virus reduced to undetectable levels, compared with 14 percent taking only the older medicines.
Also, 52 percent of patients on 20 milligrams of vicriviroc combined with other drugs had the virus lowered to undetectable levels in the blood.
Idenix Pharmaceuticals Inc. has also reported promising findings in a study of its new non-nucleoside reverse transcriptase inhibitor to treat HIV IDX899.
IDX899 demonstrated “rapid and profound” inhibition of HIV replication in a phase I/II clinical trial, the company said.
The Cambridge, Mass., biopharmaceutical company said eight HIV-1 infected treatment-naive patients receiving 800mg of the drug achieved a mean 99 percent reduction in virus level after a week of treatment in an ongoing trial.
Company officials also said they were pleased with the safety profile, as no serious adverse events were reported and no patients discontinued the study. Idenix said it now plans to explore cohorts of 400mg once-daily followed by 200mg once-daily doses.
This article appeared in the Dallas Voice print edition February 8, 2008