Hyderabad, Nov 27: A promising new vaccine to fight AIDS that employs a "dual mechanism", would enter Phase-1 human trials in America next week, it was announced here yesterday. Developed by Chiron Corporation in California, USA, the vaccine is expected to offer protection by using a simultaneous two-pronged attack on the Human Immunodeficiency Virus (HIV) that causes AIDS, company chairman William Rutter said.

Rutter, who founded the company in 1981, said the new vaccine was developed because of the realization that a single vaccine is not enough to prevent HIV from multiplying in the body.

Vaccines tried so far were designed either to attack the virus by raising antibodies against its protein coat or by activating body's own (cell-mediated) defence mechanism. This approach has not been successful as the virus changes its protein coast rather fast and also hides behind the ‘verny immune cells’ meant to fend off the virus. Rutter said the Chiron Vaccine overcomes this drawback by combining both the mechanisms and focusing on that part of the virus coat that remains constant animal trials have shown the vaccine is effective, he added. For instance, chimpanzees treated with this vaccine have remained virus free for 600 days while untreated (control) animals died of AIDS.

Rutter, who was delivering the Foundation Day lecture at the Centre for Cellular and Molecular Biology (CCMB) here yesterday, said a vaccine against Hepatitis-C is also in the pipeline. Bureau Report