A study on Truvada, a daily retroviral pill that was expected to prevent women from being infected with HIV has been abandoned, after researchers found the drug to be ineffective.
This development has been a setback, according to experts, who were surprised that the drug which had proved to be effective among a test group of homosexual men, failed in this later study.
Dr Andrew Bradley from the Mayo Clinic remarked that there were several factors that could account for this seeming discrepancy. One reason could be the subject involved did not take their medication the way they should have. Biological differences also played a vital role in the inefficacy of the drug. The probability of the women under study having been infected with drug resistant viruses needs to be considered. Or, as Dr. Bradley puts it, it could be just a statistical fluke.
Professor Sean Emery, the head of the Therapeutic and Vaccine Research Program at the Kirby Institute, commented that it was too early to say why the trial did not work, although he does state that the biological difference between the two groups under study was an important factor. And although he is disappointed over the failure of the study, he is still optimistic that using drugs to prevent infection could be an effective way of stopping the spread of AIDS. There are two other trials of similar drugs that are being carried out in sub-Saharan Africa.
Emery is also quick to point out that using drugs as a preventive measure is a 'part of an overall public health set of activities where educational interventions, behavioural change, condom use and a variety of other things that we know have well established amounts of efficacy associated with them, particularly in high risk communities.'
A separate study of children's response to retroviral drugs proved that with them drug resistance was more of a problem than with adults. The study, carried out mostly in the UK, Ireland, Spain, the Netherlands and France, with smaller numbers also from Denmark, Italy and Belgium also revealed that the drugs in use were not suited to be administered to children.
The researchers state, "There is continued need for strategies to promote optimum drug adherence in children, caregivers and young people
and for development of suitable new drugs and formulations to optimize the treatment of children with treatment failure."