In another shocking and disappointing blow to the field of AIDS research, scientists pulled the plug on a large study assessing the effect of a daily medicine regimen for women. The medication, a anti-retroviral pill named Truvada, had been proven extremely effective at preventing HIV infection in a study published last November involving gay men. Researchers initiated the current study for women as an attempt to further demonstrate the potency Truvada. However, the scientists leading the study decided to discontinue the trial upon realizing that any further length of time would not result in a statistically significant amount of protection for subjects taking Truvada versus a placebo group. Of the approximately 1,900 women enrolled in the study, 28 were infected in both the Truvada and placebo group. In other words, no beneficial effect of the medication whatsoever.
This result is especially puzzling for scientists considering that Truvada conferred over 90 percent better protection for men over the placebo group in the aforementioned earlier study.
After the shock and disappointment wears off, the team of researchers and clinicians will have to figure out how a drug that seemed so promising could fail so drastically. At the top of the list includes adherence of subjects to the medication regimen (more women on Truvada complained of side effects, which could impact how strict the subjects adhered to the daily requirement). Additionally, scientists will also go back and take another look at the data from the study published in November to see if those results, which were nothing short of remarkable, may have been overstated.
Finally, it is becoming clear that oral medication may not be the best method to provide protection from HIV infection in women. Results from a study published last summer reported that use of a vaginal gel before and after sexual intercourse protected subjects from HIV infection 54 percent better than women using a placebo. Interestingly, this gel contained tenofovir, one of the anti-retroviral drugs present in Truvada. Overall, as often happens with science, the disheartening results from this study offer more questions than answers.
Source: New York Times