New focus on HIV pipeline

The emergence of a case of AIDS in New York that is resistant to 17 of the 20 marketed drugs is a reminder that the four classes of existing drugs only address three targets on two HIV genes. Despite the fact that there are only nine HIV genes, some researchers say that all the druggable targets have not yet been addressed 18 years after the first HIV drug reached the market in 1987. Indeed, 11 of 20 drugs on the market are reverse transcriptase inhibitors (RTI), eight are protease inhibitors (PI) and both those enzymes are expressed by the same HIV gene, pol.

The "New York strain" is resistant to all marketed nucleoside RTIs (nRTIs), two of three non-nucleoside RTIs (nnRTIs) and all marketed PIs. The strain is particularly alarming because of the speed at which it progressed. Normally HIV does not convert to AIDS for about 8-10 years, according to John Shiver, vice president of vaccine and biologics research at Merck & Co. Inc. (MRK, Whitehouse Station, N.J.). By contrast, the New York strain progressed to AIDS "within two to three months and at most 20 months after HIV infection," according to the New York City Department of Health. ...