The most difficult questions about Tenofovir research concern the safety and practicality of a long-term daily drug regimen for healthy people, particularly in Africa and other parts of the developing world where regular use of medicine is uncommon. Taking the drug sporadically, researchers say, might provide only partial protection and could encourage mutant strains of HIV to develop.
There have also been strenuous objections from AIDS activists concerned about the ethics of a study in which half of all subjects receive a placebo rather than a drug that could save their lives. During research in Cambodia, where 900 prostitutes were being recruited for the trial, an organization of sex workers protested, pushing the government to suspend the study there this past summer. Hun Sen, the nation's prime minister, was quoted as saying, "If a trial is needed, please do it on animals and don't use Cambodians."
_____Recent AIDS News_____
AIDS Groups Expand Services to Other Sufferers (The Washington Post, Dec 27, 2004)
Research Flawed on Key AIDS Medicine (The Washington Post, Dec 14, 2004)
In China, an About-Face on AIDS Prevention (The Washington Post, Dec 8, 2004)
HIV Increasing Faster Among Women Than Men, Report Finds (The Washington Post, Nov 24, 2004)
Maker Removes Generic AIDS Drugs From Approved List (The Washington Post, Nov 10, 2004)
More on AIDS
_____News from Nigeria_____
Nigeria's Oil Fuels Anger, Bloodshed (The Washington Post, Dec 9, 2004)
In Nigeria, Talking Up Two Drops of Vaccine (The Washington Post, Nov 25, 2004)
Md. Woman Convicted of Harboring Girl in Enslavement Case (The Washington Post, Nov 19, 2004)
Sudan, Rebels Reach Accord On Darfur (The Washington Post, Nov 10, 2004)
Complaints have also come from advocates of traditional vaccines and microbicides who regard the study as a costly diversion from other research. Microbicides are applied to the vagina or rectum before a sexual encounter to kill the virus before it can cause infection. Supporters say that approach is more practical than taking a pill every day.
"I'm not saying that nobody is going to take it," said Morenike Ukpong of the Nigeria HIV Vaccine and Microbicide Advocacy Group. "I'm saying [the number] is very low."
The worldwide research project is projected to cost as much as $50 million, with the expense divided among the U.S. Centers for Disease Control and Prevention, the National Institutes of Health and the Gates Foundation.
The first answers to some of the questions about Tenofovir will come from the prostitutes in Ibadan, who were recruited from several brothels and have been taking pills since July. Prostitution is legal here, and the brothels attract a steady supply of women from the surrounding countryside looking for a way to finance schooling, assist struggling families or save money to start a business.
Two of the prostitutes, who spoke on condition of anonymity, said they were aware of the dangers of HIV and eager to protect themselves with the condoms and pills provided by the researchers. Both women, in their early twenties, said they had experienced no side effects.
"I take the medicine every day now," said one of the women, leaning over a brothel balcony. She was wearing a tight red dress and had coiled her hair into tight, spiky braids. Her friend, clad in a sheer black top, cooled herself with a plastic fan. "I take my medicine and I use condoms, so I think I'm safe," she said.
But like everyone else in the study, these women did not know whether they were taking Tenofovir or a placebo. The prostitutes are counseled and given unlimited access to condoms, but in a city where 22 percent of all sex workers have HIV, researchers expect some to contract the virus during the study.
That is the crux of the ethical dilemmas facing the Tenofovir trials. At an international AIDS conference in Bangkok in July, an activist group, AIDS Coalition to Unleash Power, organized protests and posted signs reading: "Tenofovir makes me sick."
Among the demands of AIDS activists is that anybody who contracts HIV during the study should be guaranteed lifetime medical treatment. Researchers have agreed to arrange for antiretroviral therapy though national public health systems, but have argued that to guarantee lifetime medical care would drive the cost of the study so high that it would become impractical.
Ward Cates, president of Family Health International, a nonprofit group in North Carolina, is overseeing several of the trials around the world. He said past HIV research showed that even those who received placebos in such studies were less likely to become infected than the general population because they also received counseling and condoms.
The first results from the study are due in 2006. If Tenofovir is found to be safe and effective, it could become available for daily use soon after because it has already been approved throughout much of the world for treating AIDS. Some even imagine Tenofovir one day being packaged with other medicines taken daily, such as birth control pills, to make it even easier to use.
"There's not a one-size-fits-all approach for trying to attack the virus," Cates said in a telephone interview from his office. "We need a full range of HIV prevention measures."