CDC Responds To End Of African PrEP

The CDC writes us this morning to note their response to the early halting of an African HIV PrEP study, which I mentioned yesterday. Pre-exposure prophylaxis (PrEP) involves taking an HIV medication as a preventive to infection. The CDC expresses disappointment with the cessation of the African study, as "this approach has already been shown to be effective in reducing HIV infection among men who have sex with men."

While PrEP with FTC/TDF was not shown to be effective in preliminary analyses of these study results, it cannot yet be definitely determined whether this drug combination works, or does not work, to prevent HIV among women. FEM-PrEP study investigators will be conducting additional analyses in the coming months to better assess potential reasons for the results in this study – including examining factors such as adherence and differential risk behavior between the two trial arms -- that may account for the lack of demonstrated efficacy in this trial. Investigators from other PrEP trials, including CDC, will be working closely with FHI to review all available data and determine any implications for ongoing research. Given today's results, CDC cautions against women using PrEP for HIV prevention at this time. We will not know if PrEP is effective for women, couples, or injection drug users until the conclusive results of this and other trials are reported.

African HIV PrEP Study Halted

Citing poor early results, researchers have halted an African study in which women were given the HIV medication Truvada as a preventive to infection. Pre-exposure prophylaxis (PrEP) has been considered one of the more promising advances against AIDS.

Women taking Truvada, made by Gilead Sciences Inc., are just as likely to get HIV as other women who have been given dummy pills, an interim analysis of the study found. Even if the study were to continue, it would not be able to determine whether the pills help prevent infection, since the results are even this far along, researchers said. The finding is disappointing because another study last fall concluded that Truvada did help prevent infections in gay and bisexual men when given with condoms, counseling and other prevention services. Many AIDS experts view that as a breakthrough that might help slow the epidemic.

Last month the U.S.-based AIDS Healthcare Foundation denounced a similar study for gay men, saying, "There is no magic pill." Truvada costs as much as $14,000/year in the United States, but is available in generic form overseas for as little as $140/year.

Identity Gap

The Wall Street Journal looks at recent estimates of the size of the LGBT community in the United States and why some consider such figures to be inherently unreliable.

Turning Gay Mice Straight?

The science journal Nature has published a study claiming that the sexual orientation of mice can be changed with the neurotransmitter 5-HT.

Although the question of to whom a male directs his mating attempts is a critical one in social interactions, little is known about the molecular and cellular mechanisms controlling mammalian sexual preference. Here we report that the neurotransmitter 5-hydroxytryptamine (5-HT) is required for male sexual preference. Wild-type male mice preferred females over males, but males lacking central serotonergic neurons lost sexual preference although they were not generally defective in olfaction or in pheromone sensing. A role for 5-HT was demonstrated by the phenotype of mice lacking tryptophan hydroxylase 2 (Tph2), which is required for the first step of 5-HT synthesis in the brain. Thirty-five minutes after the injection of the intermediate 5-hydroxytryptophan (5-HTP), which circumvented Tph2 to restore 5-HT to the wild-type level, adult Tph2 knockout mice also preferred females over males. These results indicate that 5-HT and serotonergic neurons in the adult brain regulate mammalian sexual preference.

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A Gay Caveman?

The discovery of a 5000 year-old skeleton in the Czech Republic has scientists speculating.

During that period, men were traditionally buried lying on their right side with the head pointing towards the west; women on their left side with the head facing east. In this case, the man was on his left side with his head facing west. Another clue is that men tended to be interred with weapons, hammers and flint knives as well as several portions of food and drink to accompany them to the other side. Women would be buried with necklaces made from teeth, pets, and copper earrings, as well as domestic jugs and an egg-shaped pot placed near the feet. The ‘gay caveman’ was buried with household jugs, and no weapons.

Archaeologists do not think it was a mistake or coincidence given the importance attached to funerals during the period, known as the Corded Ware era because of the pottery it produced. From history and ethnology, we know that people from this period took funeral rites very seriously so it is highly unlikely that this positioning was a mistake,’ said lead researcher Kamila Remisova Vesinova. ‘Far more likely is that he was a man with a different sexual orientation, homosexual or transvestite. What we see here does not add up to traditional Corded Ware cultural norms.’ An oval, egg-shaped container usually associated with female burials was also found at the feet of the skeleton.