Lunes 15 de Julio de 2002, Ip nš 19

Aids vaccine 'may be ready within five years'
An American pharmaceuticals company today claimed to be in the final stages of testing an Aids vaccine, possibly providing a working vaccine within five years.

Californian company VaxGen planned to present its preventative vaccine, called Aidsvax, to the international Aids conference in Barcelona later today. Two trials are being conducted on 8,000 people in the Thailand, the US, Canada, Puerto Rico and the Netherlands. Preliminary results are expected by spring 2003.

Vaxgen said that Aidsvax "has a strong safety profile and induces an immune response in nearly everyone who receives it". The vaccine relies on genetically engineered proteins to produce an immune response, not the HIV virus, so it cannot cause HIV infection, Vaxgen said.

The company explained on its website: "Aidsvax induces the immune system to produce antibodies. These antibodies are designed to attach to the protein on the virus surface [gp120] that HIV uses to fuse through and infect healthy cells. If the antibodies can prevent the virus from attaching to healthy cells, it is believed that they can prevent infection."

The Vaxgen vaccine is one of only eight being tested on humans to a "significant degree", the BBC reported today, and the only one in an end-stage trial.

Vaxgen will have to prove the vaccine is effective in at least a third of patients in order to be granted a licence.

Jose Esparza, coordinator of the Geneva-based UNAids HIV vaccine initiative, said: "It is a bit premature for the company to say it expects it to be effective. We have to be very cautious and to prepare ourselves for when the results are going to be announced."

But Mr Esparza also praised VaxGen's commitment, saying: "Unless we go through these difficult trials we will never have a vaccine, and the company needs a lot of support."

He added that even if it the vaccine only worked on half the people immunised, the result would be significant.

Evan Harris, the science spokesman for the Liberal Democrats, warned that immunisation could still be "a long way off". Dr Harris was a healthy volunteer in an early stage trial for another possible vaccine, and he said today there was no proof that any of immune drugs would be effective.

"Everyone involved in researching the vaccine candidates is hoping against hope that one or more of them will actually work," he said. "But proof of effectiveness is still needed and that is why a vaccine is such a long way off."

He added that "the key point for policy-makers and politicians in the developed world is to guarantee now that funding to manufacture and above all deliver a vaccine programme will be available if the research goes well".


  08/07/2002. The Guardian.