GSK加速爱滋病药物的研究

生物谷

GlaxoSmithKline (GSK)称其在临床II期试验结束之前，已经启动了一个非常有潜力的爱滋病药物的临床III期试验。这一举动在分析师看来正反映了许多公司竞争研发治疗爱滋病的“重磅炸弹级药物”的现状。 Aplaviroc被设计为在病毒进入人类细胞前阻碍它。这一药物是从日本的Ono Pharmaceutical转让的技术。

GlaxoSmithKline Plc said on Monday it had begun final Phase III trials in June of a new kind of pill that can block the AIDS virus before it enters human cells.

The experimental medicine, known as a CCR5 inhibitor and called aplaviroc or GSK 873140, was licensed from Japan's Ono Pharmaceuticals, which received a milestone fee from Europe's biggest drugmaker following the start of the studies.

GSK's decision to launch Phase III tests, even though Phase II trials have not yet been completed, reflects the race among rival drugmakers to be first to market with the new kind of AIDS treatment.

If successful, CCR5 inhibitors should have fewer toxic side effects and offer hope to patients whose virus has developed resistance to existing antiretroviral medicines.

Industry analysts estimate that a successful CCR5 drug should generate sales of $500-700 million a year, with the first products likely to reach the market in 2007 or 2008.

Other companies working in the field include Pfizer Inc, which started Phase III testing several months ago, and Schering-Plough Corp.

News of the latest drug trials was disclosed by GSK on the sidelines of the International AIDS Society conference being held in Rio de Janeiro.

Joseph Eron, Professor of Medicine at the University of North Carolina, said the new drugs could provide an important treatment option for people with HIV/AIDS, by offering a different mode of action and an improved toxicity profile.

Most existing HIV drugs work inside the body's immune cells, after the virus has infected -- and they can cause anaemia, nerve pain, diarrhoea, fat wasting and even organ damage.

That has led researchers to study other approaches.

Switzerland's Roche Holding AG and U.S. biotech group Trimeris Inc launched the first drug, Fuzeon, to stop HIV from entering healthy immune cells in 2003.

But Fuzeon is expensive, must be injected twice daily and sales -- $135 million in 2004 -- have been disappointing.

The new drugs can be given as a tablet and work by locking a cellular doorway, or co-receptor, called CCR5.

The idea for the drug class came from the observation that people with mutated CCR5 can resist HIV infection, even after exposure to numerous high-risk sexual partners. Just under 2 percent of Caucasians carry the mutation.

Ono said it would book the milestone payment for the start of Phase III trials in the April-June quarter. The size of the payment was not discloSed.