Science & Medicine

Experimental Microbicide Shows Small Level of Protection Against HIV for Women, Study Presented at CROI Indicates

[Feb 10, 2009]

Research has shown "a small amount of protection from a vaginal gel that acts by binding up the AIDS virus and preventing it from invading cells," according to a study presented Monday at the 16th Conference on Retroviruses and Opportunistic Infections in Montreal, Canada, the Washington Post reports (Brown, Washington Post, 2/10). The experimental microbicide, called PRO 2000 and manufactured by Indevus Pharmaceuticals, is designed to prevent HIV from attaching to certain white blood cells. According to the study -- which primarily aimed to test the gel's safety -- the PRO 2000 gel is 30% effective in preventing HIV infection. Although the findings are not statistically significant, the study is the first to demonstrate a possible beneficial effect from using microbicides. According to NIH, an effectiveness rate of 33% would be statistically significant.

For the NIH-funded study, Salim Abdool Karim of the Center for the AIDS Program of Research in South Africa and colleagues divided 3,100 women from Malawi, South Africa, the U.S., Zambia and Zimbabwe into four groups - one that used the PRO 2000 gel; a second that used ReProtect's microbicide gel BufferGel; the third that used a placebo gel; and the remaining group used no microbicide gel. All the women received counseling to encourage condom use (Stobbe, AP/Google.com, 2/9). At the conclusion of the 20-month study period, 194 women had contracted HIV, including 36 women from the PRO 2000 group, 54 from the BufferGel group, 51 from the placebo group and 53 from the group that used no microbicides.

According to NIH, participants reported use of the gels in 81% of sex acts. Kathy Stover, NIH communications officer, said the study was based on self-reporting, and therefore the researchers "have no way to verify that the gel was actually applied prior to sexual intercourse" (Reichard, CQ HealthBeat, 2/9). According to health officials, further research will be necessary to determine the gel's efficacy. London's Medical Research Council currently is conducting a study of the PRO 2000 gel involving 9,500 women, which is three times the size of the first study, Bloomberg reports (Lauerman, Bloomberg, 2/9).

Researchers for many years have worked to develop effective microbicides to prevent HIV transmission, but no earlier studies have shown promising results and two trials showed that the gels actually increased the risk of contracting HIV. According to the Post, microbicides have advantages over other HIV prevention methods because they can be applied without the knowledge of sexual partners. This is particularly important in places where cultural practices might limit a woman's ability to insist on abstinence or condom use (Washington Post, 2/10). Karim, who presented the PRO 2000 study at the conference, said, "while not conclusive, [it] provides a glimmer of hope to millions of women at risk for HIV, especially young women in Africa" (AFP/Google.com, 2/9).

PrEP with Antiretrovirals Shows Promise in Preventing Monkey Form of HIV

In related news, two additional CDC studies presented at CROI found that pre-exposure prophylaxis, or PrEP, with antiretroviral drugs administered by mouth or by vaginal gels were highly effective at protecting rhesus macaques from the simian version of HIV, or SIV, the Post reports.

For the first study, the researchers gave the monkeys oral doses of a compound containing the antiretroviral drugs tenofovir and emtricitabine, sold under the brand name Truvada. The researchers administered the drugs at different intervals -- called intermittent PrEP -- both before and after exposing the macaques rectally to SIV once weekly for three months. Of the monkeys that received the first dose one or three days prior to contact with the virus, five out of six were protected from SIV. Monkeys in all five treatment groups had significantly lower risk of infection compared with the untreated monkeys, and PrEP was most effective in preventing infection if administered one to seven days prior to exposure compared with immediately before exposure or only intermittently after exposure. According to Gerardo Garcia-Lerma, CDC epidemiologist and lead author of the study, tenofovir has a long active life in the body; however, it might take longer than two hours for the drug to enter the immune system and provide protection against the virus.

For the second study, the researchers tested vaginal gels containing either the combination drug or tenofovir alone. They applied the gel to macaques 30 minutes before twice-weekly exposure to SIV. According to the study's findings, all of the six monkeys that received the two-drug gel and all of the six monkeys that received the tenofovir-only gel were protected from the virus. Out of 11 macaques that received no gels, 10 contracted SIV after a median of four exposures to the virus (Washington Post, 2/10). The study's findings suggest that single-drug vaginal gel formulations are equally effective as combination-drug formulations in providing complete protection against SIV (CDC release, 2/9).

Walid Heneine -- laboratory chief of CDC's Division of HIV/AIDS Prevention, who led the second study -- said the results are "very promising, although we're waiting for the results of human trials to see if they correlate with animal studies." Warren added that results of the studies are "very exciting" but added that "we mustn't be too optimistic that we'll see the same results in people" (Bloomberg, 2/9). According to the Post, seven studies are currently underway to test the efficacy of Truvada and tenofovir as HIV prevention methods when administered daily. About 18,000 people from Botswana, Kenya, Thailand, the U.S. and Uganda are participating in the studies (Washington Post, 2/10).

Men Taking HAART Can Transmit HIV Through Semen

An additional two studies presented at the conference indicate that men who take highly active antiretroviral therapy may still transmit HIV to sexual partners through their semen, Reuters reports. For the studies, Prameet Sheth of the University of Toronto and Anne-Genevieve Marcelin of Pitie-Salpetriere Hospital found that men who had undetectable HIV viral loads in their blood still carried the virus in their semen. Sheth told reporters at the conference, "I would argue that it is infectious although we don't know what level of virus is required." According to the researchers, it is unclear why HAART can bring down viral loads to undetectable levels in the blood but not eliminate the virus from semen. (Reuters, 2/9).

Research Funding Aims at HIV Cure

Bloomberg recently examined the "offering [of] bounties to a new wave of scientists to wipe out HIV." The U.S. has asked researchers to create a program aimed at developing a cure for HIV/AIDS, and the Bill & Melinda Gates Foundation has offered $100,000 grants for research on permanently eliminating the virus from the body. According to Bloomberg, pressure to develop successful HIV/AIDS treatments has increased in recent years, following the 2007 failure of an experimental Merck vaccine and similar disappointments from vaginal microbicide trials.

According to Bloomberg, NIH has sought to fund proposals that will research how HIV remains in the body even after antiretrovirals reduce the viral load to undetectable levels. The Gates Foundation is seeking proposals with the same goal, according to Bloomberg. The persistence of HIV in the body is expected to be a major topic at CROI, according to Bloomberg. Anthony Fauci, director of NIH's National Institute of Allergy and Infectious Diseases, said it is "very easy" to reduce HIV loads to undetectable levels. "However, to knock it out, we'll either have to get true eradication, or get the reservoir of virus that's inside cells so low that it can't come back," Fauci said. He added that it might be possible to develop a "functional cure" for HIV that would allow the immune system to handle the virus without drugs, similar to remission for cancer (Lauerman, Bloomberg, 2/9).

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Global Challenges

PBS Program Examines Impact of Global Economic Crisis on Health Funding

[Feb 10, 2009]

PBS' "News Hour" last week examined the impact of the global financial crisis on funding for health services in developing countries. According to "News Hour," the World Bank is planning to triple the loans it provides in the health sector this year in response to the crisis. Julian Schweitzer -- sector director for health, nutrition and population at the World Bank -- said that $950 million in loans for the health sector was approved in 2008 and that the amount is expected to increase to about $3 billion in 2009. The bank has seen an increase in the number of loan requests and is focusing on countries in Africa, Asia and Latin America, which are considered to be at an increased risk from the economic crisis. Schweitzer said that in times of economic recession, the health sector "seems to get hit the hardest by budget cuts" and that women's and children's health "are particularly badly hit." Over the past 25 years, an estimated one million children died because of expenditure cuts by governments in response to economic downturns, Schweitzer said, adding that the World Bank is advising countries to focus spending on specific programs, such as nutrition for pregnant women or child immunization.

In addition, the Global Fund To Fight AIDS, Tuberculosis and Malaria recently announced that it is facing a $5 billion funding gap through 2010. There also has been an increase in new funding requests from eligible countries, "News Hour" reports. Andrew Hurst, spokesperson for the group, said the demand for funding is "much higher than we expected, so if we are going to meet that demand, we are going to need more money than what is coming in." The last round of Global Fund grants in December 2008 was reduced by 10%, from $3.1 billion to $2.75 billion, although all program requests were approved. Recipients were asked to achieve the same goals with reduced funding through changes like cuts in overhead costs or finding lower cost options for pharmaceuticals, according to "News Hour."

According to Ruth Levine -- a health economist and vice president for programs and operations at the Center for Global Development -- more than 50% of the total public health spending in some developing countries, such as many in sub-Saharan Africa, come from aid commitments. She added that many of those countries do not have social safety nets to protect people from economic downturns. Levine said, "When national budgets are squeezed because of falling tax revenues and falling donor contributions the social services for the poor are some of the first to be jeopardized." She added that foreign aid in economic recessions "tends to be a pretty easy target" that "doesn't have a very deep constituency -- voters at home don't feel it when it's cut." Levine also said that people living with HIV/AIDS and other diseases in developing countries risk seeing their treatments interrupted as a result of funding shortfalls. She said decreases in aid for these programs "affect individuals who are dependent on these resources for lifesaving drugs," adding, "So the stakes are much, much higher than in the past" (Miller, "News Hour," PBS, 2/6).

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The Australian Examines HIV/AIDS in Papua New Guinea

[Feb 10, 2009]

The Australian on Saturday examined HIV/AIDS in Papua New Guinea. According to The Australian, HIV is spreading in the country in large part because of stigma, polygamy and high-risk behaviors, particularly among men. Approximately 2% of the population is living with HIV, and by 2012 that figure could reach 5%, The Australian reports. Almost 50% of Australia's annual $358 million in aid to Papua New Guinea is devoted to HIV/AIDS programs, and 70% of the country's health resources soon will be allocated to programs addressing the disease. Tessie Soi -- coordinator of social work at Port Moresby General Hospital and founder of the nongovernmental organization Friends Foundation -- said that she often arranges burials for HIV-positive people who are abandoned by their families because of their status. She added that in 2007, there were almost 4,000 infants orphaned by HIV/AIDS. The Australian also profiled several HIV-positive people living in Papua New Guinea (Toohey, The Australian, 2/7).

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Across The Nation

New Orleans Program Will Provide HIV, STI Testing, Treatment to Inmates

[Feb 10, 2009]

A new program launched at the New Orleans Parish jail will provide inmates with testing and treatment for HIV and other sexually transmitted infections, Criminal Sheriff Marlin Gusman announced on Friday, the New Orleans Times-Picayune reports. According to Gusman, the program also will provide people with information about clinics that can continue care after they are released.

Although not everyone who is arrested and booked at the jail's Intake and Processing Center will be offered the testing, those who stay at the jail for a few days will receive the comprehensive STI testing, counseling and any needed treatment, the jail's Medical Director Samuel Gore said. According to Gusman, targeting the population is important because inmates are the "most at-risk population." The program is run in partnership with city and state health offices, which will supply staff and laboratory support to jail medical staff. According to the Times-Picayune, the state Office of Public Health will work with people who test positive for STIs.

The tests will include those for HIV, gonorrhea, chlamydia and syphilis, and inmates will be referred to the Delgado Personal Health Clinic once they are released. The program is based on an initiative that began in 2008 to provide female inmates with HIV testing, counseling and treatment. According to Gore, the program was popular among the inmates, many of whom were receptive about learning their HIV status. "Mostly they hear about it from someone else, and they offer to get tested themselves," he said, adding, "They are volunteering" (Maggi, New Orleans Times-Picayune, 2/7).

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Opinion

Pediatric HIV/AIDS 'Preventable Tragedy,' Opinion Piece Says

[Feb 10, 2009]

"The revolution of our generation -- this generation -- is to create a generation free of HIV," Pamela Barnes, president and CEO of the Elizabeth Glaser Pediatric AIDS Foundation, and Nicholas Hellmann, executive vice president of medical and scientific affairs for the foundation, write in a Globe and Mail opinion piece. "Imagine if we had a safe, effective, inexpensive vaccine for a deadly disease but we didn't use it," they write, adding, "Now imagine that reality for more than a million HIV-infected pregnant women each year and their HIV-infected children, who face a high probability of serious illness and early death." According to Barnes and Hellmann, 1,000 new pediatric HIV cases occur daily worldwide -- with 90% of the new cases occurring in sub-Saharan Africa -- and more than 700 children die from AIDS-related causes daily. They add that the main cause of pediatric HIV is mother-to-child transmission, and without early treatment, about 50% of infants living with HIV will die before age two. Barnes and Hellmann write, "This is an unimaginable, astonishing and entirely preventable tragedy."

In sub-Saharan Africa, the foundation has utilized "what is called PMTCT, or Prevention of Mother-to-Child Transmission," the authors write, adding that PMTCT is the "drug equivalent of a vaccine." In addition, PMTCT is "[i]nexpensive" and "relatively simple to administer" and can "reliably prevent most transmissions of HIV from a mother to her infant," according to Barnes and Hellmann. Although use of PMTCT in the U.S. has decreased the number of pediatric HIV cases to between 100 and 200 annually, almost 370,000 new cases occurred in the developing world in 2007, the authors write, adding that 270,000 children died of AIDS-related illnesses in the same year, more than two million children are living with HIV worldwide and about two-thirds of women in low- and middle-income countries do not have access to PMTCT. "This is an astonishing failure not of science, but of implementation," they write, adding that PMTCT is a "method tantamount to a vaccine" that "remains inexplicably underresourced and underutilized."

Although there has been "significant progress" in expanding access to PMTCT in developing countries, "dramatic scale up of PMTCT programs in the areas hardest hit by HIV and AIDS is still desperately needed," they continue. "HIV prevention, diagnosis, care and treatment should be integrated with other public health interventions," they write. "To succeed, we must work together with organizations and partners to maximize the impact of dollars spent and to develop more innovative solutions customized to local settings," the authors write, adding that success depends on "mak[ing] proven prevention methods available to everyone who needs them." Additionally, Barnes and Hellmann write that coordination between "contributors, implementers and countries facing this pandemic" needs to be promoted "to build the scalable and sustainable health programs that will stop this devastation in its tracks." They conclude, "Every day, together, we must commit to achieving a generation free of HIV. This is the revolution of our generation, a revolution we must fight for those who follow behind us" (Barnes/Hellmann, Globe and Mail, 2/9).

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