Interim data from human clinical trials of two AIDS vaccine candidates, named DNA.HIVA and MVA.HIVA

At the AIDS Vaccine 2004 conference, August 30–September 1 in Lausanne, a partnership led by the International AIDS Vaccine Initiative (IAVI) presented interim safety and immune response data from human clinical trials of two AIDS vaccine candidates, named DNA.HIVA and MVA.HIVA. The candidates are designed to elicit a cell-mediated immune response to prevent HIV infection and AIDS.

The partnership includes the University of Oxford/UK Medical Research Council, the University of Nairobi/Kenya AIDS Vaccine Initiative and the Uganda Virus Research Institute. The partners have been working since 1998 to develop DNA.HIVA and MVA.HIVA.

The interim data, from 205 volunteers in clinical trials in Kenya, Uganda and the United Kingdom, show that DNA.HIVA and MVA.HIVA are generally safe and well tolerated. However, the candidates’ ability to elicit an anti-HIV cell-mediated immune response is poor, using currently accepted measures of immune response. The candidates elicited responses in, at most, a quarter of volunteers who received them, and the responses were not long-lasting.

The data fall short of expectations, and they show that the promise manifest in preclinical studies of DNA.HIVA and MVA.HIVA has not held up in humans.

Over the next six to nine months, IAVI will complete a small number of clinical trials that have already started of DNA.HIVA and MVA.HIVA, in order to learn as much as possible from the candidates. Unless there are new immune response data that are dramatically different, IAVI will not develop the candidates further, and will focus on its other research and development projects.