A study of HIV-negative injection drug users (IDUs) in Vancouver, British Columbia, found that about a third expressed willingness to take Truvada (tenofovir/emtricitabine) as pre-exposure prophylaxis (PrEP) to prevent HIV. Publishing their findings in AIDS Behavior, researchers gave questionnaires to 543 HIV-negative IDUs enrolled in the Vancouver Injection Drug Users Study. The questionnaires, which asked about knowledge of and interest in PrEP, were administered between December 2012 and May 2013.

Sixteen (3 percent) of the participants already knew about PrEP. After being informed about Truvada, 192 (35.4 percent) said they were willing to take the daily oral medication if it were made available to Canadians. (The drug, which is also used to treat HIV in combination with other antiretrovirals, is currently only approved as PrEP in the United States.)

After adjusting for various factors, the researchers found that younger age was associated with a 30 percent greater likelihood of interest in PrEP for every relative decade of youth. In addition, those who were not regularly employed were 67 percent more likely to use PrEP than those who had a regular job; those engaging in sex work were 2.29 times as likely to use PrEP than those who did not engage in sex work; and those who reported more than one sex partner in the past six months were twice as likely to express interest in PrEP as those who reported no sex partners.

Out of the 192 participants who expressed interest in taking PrEP, 115 (21.2 percent) said they were still willing to do so after being informed of Truvada's potential side effects, which nurses described to them as including nausea, abdominal pain, headache, weight loss and, rarely, kidney failure or bone toxicity. When told that PrEP might not have 100 percent efficacy, 136 (25 percent) of the participants were still willing to take PrEP.

To read the study abstract, click here.