Dr. Nyaradzo Mavis Mgodi is often asked about an antibody now being tested in clinical trials to see if it can protect women from HIV.
She begins by talking about Mary Moyo.
Mary was 18 when she married 27-year-old Mike in Harare, Zimbabwe. When Mary became pregnant, she and Mike were tested for HIV. Mary tested negative, but Mike was found to have HIV.
Their doctor recommended that Mike use condoms to protect his wife from infection. Mike refused, saying he had paid lobola, or bride price, to Mary’s parents and could do whatever he wanted. He beat her if she refused to have unprotected sex.
“All over southern Africa, women like Mary suffer silently,” Mgodi said, after recounting Mary’s story most recently at the international AIDS 2016 conference in Durban, South Africa. “There are millions of women who need empowerment. That is why we are embarking on the AMP study.”
A researcher at the University of Zimbabwe-University of California San Francisco Collaborative Research Program in Harare, Mgodi will discuss what AMP — antibody-mediated prevention — could mean for women like Mary today at a meeting of the 2016 HIV Research for Prevention, or HIVR4P, conference in Chicago. The international gathering of researchers and activists focuses on all methods of preventing HIV infections.
Mary’s story had a happier ending than many, Mgodi said. She fled the beatings — and the marriage — before becoming infected with HIV. Now she is trying to start her life over.
Mgodi is determined to help her and other sub-Saharan African women by finding a way they can protect themselves from HIV infection without their partners' help.
The AMP HIV Prevention Study is actually two parallel studies that will eventually involve more than 4,000 participants on three continents. Leading it are Dr. Larry Corey, founder and director of the HIV Vaccine Trials Network (HVTN), headquartered at Fred Hutchinson Cancer Research Center, and Dr. Myron Cohen, head of the HIV Prevention Trials Network based in Durham, North Carolina.
One study began enrolling volunteers in the U.S., Peru and Brazil last spring to test whether intravenous infusions of these neutralizing antibodies can prevent HIV infection in men and transgender people who have sex with men.
The second study, the one Mgodi is co-chairing, is being done in Botswana, Kenya, Malawi, Mozambique, South Africa, Tanzania and Zimbabwe and will test whether the antibody infusion works in women. If it does, the finding will have particular significance for an epidemic that hits women on that continent especially hard and for which they have few prevention options.
Globally, women make up half of the 36.7 million people living with HIV, and 80 percent of infected women live in sub-Saharan Africa, the region hardest hit by the pandemic. Young women ages 15 to 24 are at particular risk and are two to eight times more likely to be infected than their male peers, often through sex with an older male partner, said Dr. Kathryn Mngadi, a physician-scientist and HVTN researcher at the CAPRISA eThekwini research clinic in Durban, South Africa.
“If we want to change this epidemic,” Mngadi said, "we need to concentrate on women.”
The reasons behind the sub-African epidemic in women are multiple and complex. Most infections in sub-Saharan Africa are transmitted heterosexually. For biological, socioeconomic and cultural reasons, women are more vulnerable than men to acquiring HIV during sex.
Biologically, the vagina offers a mucosal surface area for pathogens and infectious fluids to enter. Studies at CAPRISA have found that the microbiome of the vagina, which differs across locations and ethnicities, can include bacteria that increase the likelihood of HIV infection or decrease the effectiveness of anti-HIV vaginal microbicides (and potentially other HIV prevention methods).
Another risk factor is economic: In a country with even fewer employment options for women than men, young women often enter into sexual relationships with older men known as “blessers” who “bless” them with money for food, clothes and school supplies. Simply by virtue of age, these blessers are more likely to have been exposed to and contracted HIV. And because men tend to have fewer contacts with health clinics, they are less likely to be on antiretroviral medication to suppress the virus and limit transmission. Later on, a young woman may settle down with someone her own age, but by then she has HIV and passes it on to her new partner, completing the cycle.
Yet another reason women are especially susceptible is cultural, said Mngadi. Whether in a relationship with a blesser or a husband, in a culture in which men dominate relationships, women often can’t negotiate safer sex practices such as condom use or taking a daily antiretroviral pill known as PrEP to prevent infection. (While available in the U.S., the PrEP pill is not yet approved or widely available in most of sub-Saharan Africa.) One of the appeals of a vaccine or a long-acting injectable PrEP — both of which are now ramping up for clinical trials — is that they can be used discretely, without a woman’s partner even knowing.
At 20, Banqobile Mzeka has never lived in a world without HIV. “Some are suffering, some have died,” she said of her own family, speaking softly and hesitantly in English rather than her native Zulu.
Mzeka came to the eThekwini site to take part in the AMP trial for one reason, she said: “To help.” Her mother has also volunteered for clinical trials there.
Mzeka lives in tin-shack township north of Durban that is among the poorest in South Africa. HIV rates among pregnant women in the KwaZulu-Natal province of South Africa exceeds 40 percent. South Africa has the highest HIV infection rate in the world, and KwaZulu-Natal, which includes Durban and its surrounding townships, is the epidemic’s epicenter.
Women can be easier than men to recruit to clinical trials. As the family caregivers, they are motivated to help.
“Women know other women who have been infected or are ill with AIDS — family or friends —and are more driven to participate in research for the betterment of others,” Mngadi said.
That’s good news for Musa Gumede, who does community outreach for the eTheKwini site. Recruiting for the AMP trial is especially challenging because of the time commitment required: Each volunteer — all at risk for HIV infection but HIV-negative when they enter the study — will receive a total of 10 infusions, once every eight weeks, and will be followed for 20 weeks after that, for a total of about 22 months per volunteer. The overall study is expected to take about five years.
“I recruit for different trials, but now I’m on AMP. It’s new, and there’s a lot of explaining,” Gumede said. The challenge is the amount of time at the clinic. And a lot of people haven’t used an IV before.”
Still, so far, the site is exceeding recruitment projections.
Another recruiting advantage is that women tend to seek out health care services more readily than men. Indeed, Mzeka volunteered for the trial not just to help others but to help herself.
“I decided to come here so I don’t get [HIV],” she said.
The AMP study will be a randomized, double-blind, placebo-controlled clinical trial — the “gold standard” of clinical trials. Study participants will be randomly assigned to one of three groups, with one-third receiving a higher dose of antibody in their IV, one-third a lower dose and one-third the placebo — an infusion of sterile salt water with no antibodies. “Double-blinded” means that neither the trial investigators nor the participants will know which participants are assigned to which group until the end of the trial, when the coded records are “unblinded.”
The trial organizers are careful to explain to Mzeka that she won’t know whether she’s getting the actual antibody, or even if she is, whether it will be protective. Still, she, like all participants is counseled on how to reduce the risk of contracting HIV. And like all trial participants, she is regularly tested and gets regular health checkups.
“Just being in a trial, she’s in a safe place,” said Nkosikhong “Uzzi” Mpungose, a member of the eTheKwini volunteer community advisory board.
Farther south in Cape Town, Dr. Linda-Gail Bekker, deputy director of the Desmond Tutu HIV Centre and an HVTN researcher, is also involved in the AMP study. She is doing a sister study in which scientists look at genital mucosal biopsies from women participating in the trial to see “what role the antibody plays on the business end, if you like, where the virus is going to be coming in and taking hold.”
Bekker is aware of the challenges posed by the trial: the intravenous drip, which is uncommon in much of sub-Saharan Africa, and the time commitment involved. Still, she's heartened by the recruitment progress so far.
“Nelson Mandela always said ‘It’s difficult until it’s done,’” she said. “People are coming in, they’re getting their infusions, the world has not stopped spinning. It’s doable and feasible.”
The goal of the AMP trial is to see if the antibodies provide protection as hoped. If so, information gleaned from the study could help scientists figure out how to reverse-engineer a vaccine to elicit the antibodies in the concentrations needed or develop another less-onerous way to deliver them.
The first woman from Africa to become president of the International AIDS Society, Bekker sees firsthand, every day, the need for HIV prevention methods that women can control. She is one of four South African scientists — all women — to lead a soon-to-launch HVTN clinical trial that could lead to the first licensed HIV vaccine regimen, albeit one that does not elicit this type of antibody and may provide only partial protection. She knows how helpful even a partially effective vaccine would be, and why better, more effective methods need to be in the pipeline.
“We have 300 new infections in young girls in this country every single day,” she said in an interview this summer in her Cape Town office. “In a week, we have [what equates to] a whole high school of girls become infected with HIV. Every single week. That’s a Twin Tower of young girls going down with HIV every single week.”
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Fred Hutch News Service writer Mary Engel and multimedia editor Robert Hood were in Durban and Cape Town, South Africa, where this story was reported, in July for the 21st International AIDS conference, AIDS2016.