Last year, South African epidemiologist Quarraisha Abdool Karim, Ph.D. was awarded the TWAS-Lenovo Science Prize -- one of the most prestigious science awards given to researchers in the developing world -- for her momentous contribution to the field of HIV prevention. For over 20 years, she has devoted her research to understanding why young women in South Africa are getting HIV at such astoundingly high rates, in order to ultimately develop and test new technologies to help women take control of their sexual health and quell the epidemic in this region and around the world.
Abdool Karim's research focused on South Africa -- a country that bears 1% of the world's population but 17% of its HIV infections. This astoundingly disproportionate disease burden spurred Abdool Karim's interest in understanding why HIV rates were so high.
She began doing population-based surveys in the 1990s to better understand how the epidemic was playing out in her country. She found that men and women were contracting HIV at different points in their lives. Women were becoming infected at a much earlier age -- around age 15 -- compared to men who were more often infected in their 20s. This led her to begin a series of studies with women from different settings in KwaZulu-Natal, South Africa to try to understand what was going on.
"Women in urban settings, in peri-urban, in rural ... young women, older women, mothers of teenagers, sex workers -- you name any group of women, and I worked with them between 1991 and 1994," notes Abdool Karim.
She found that oftentimes, the women she surveyed didn't have much control over their exposure to HIV.
"When you look at the epidemiology, and what you have available for prevention -- abstinence, behavior change, male/female condoms, medical male circumcision, even treatment as prevention -- a lot of these actually have very little space for women and young women who are unable to get their partners to do all of these things. For example -- by being faithful to them or using condoms," she explained.
It was clear to her that women needed an HIV prevention resource that they could use on their own -- without input or buy-in from a partner -- that could lower risk.
"One of the most important groups I worked with were sex workers who worked at truck stops midway between Durban and Johannesburg. I found that women didn't always insist on condom use. If they used condoms, they'd only earn 25% of what they would earn if they didn't use condoms. So they'd have to work four times harder. Back in 1992, that's when the sex workers started to say, can't you give us something that we can control and use? That way we can use it when we need to use it -- we don't have to negotiate this with our clients or intimate partners."
That's around the time when she first started hearing about microbicides: chemicals that can be inserted into the genital tract before and/or after sex to prevent HIV. Abdool Karim linked up with Ronald Roddy at Family Health International to conduct a study using nonoxynol-9 to prevent HIV among women in West Africa. A few years later, she was asked to set up the National AIDS Program, which became part of the center that her husband, Salim Abdool Karim, was running at the South African Medical Research Council. With more exposure and funding from the National Institutes of Health network and HIV Prevention Trials Network, she continued to test new products that came down the drug pipeline.
Between 2007 and 2010, Abdool Karim led a pioneering study establishing the safety and efficacy of a vaginal microbicide gel. The CAPRISA 004 study was a Phase two clinical trial conducted with almost 900 women in the KwaZulu-Natal province of South Africa. The study produced strong evidence that a topically-applied gel could prevent HIV infection. During the study, women using the vaginal microbicide were significantly less likely to contract HSV-2 (the virus that causes genital herpes) in addition to HIV, than women using a placebo gel.
It was an exciting -- and groundbreaking -- win for Abdool Karim and her team. This proof-of-concept study established microbicides as worthy of further investigation. It also provided the first evidence that an HIV antiretroviral medication -- tenofovir, in a 1% gel -- could be topically applied to prevent HIV.
When Abdool Karim presented the CAPRISA 004 findings at the 2010 International AIDS Conference, she received a standing ovation -- a rare occurrence at scientific meetings.
"I do a lot of presentations at meetings and conferences. That experience does stand out as one of the most emotional responses -- and [it was] overwhelming. I think it speaks to that time in our history. Sexual transmission is the dominant mode of HIV transmission yet remains a challenge. By 2010, the scientific community had tested about 42 interventions to prevent HIV infection and only 5 trials had yielded a positive result -- the three medical male circumcision trials, the Thai vaccine trial and the Mwanza sexually transmitted disease treatment study. The 004 study gave people hope about a method for women. It just caught people's imagination and injected a lot of energy into the field. For people like myself, who have been in the trenches for close to two decades, it was just an incredible moment."
Abdool Karim also sees how CAPRISA 004's positive results helped stimulate renewed investment into novel HIV prevention products that women can control. Besides gels, foams, or films that can be applied in the vagina or rectum before or after sex, vaginal rings and injectables are also in the development pipeline. Looking forward, she's hopeful that microbicides can be just one option out of many that may be available for women to use.
"I don't see microbicides as the only prevention tool. I can imagine a world where in a few years, the landscape looks very much like what we now have for contraceptives. You have orals, you have injectables, you have long-acting implants, you have IUDs. ... Women can choose what they need or suits them the most at different times of their lives. Women have as much as a right to take control over whether they get infected as men do. So it helps empower women who are in relationships where they're unable to negotiate monogamy or condom use or have their partner circumcised. Or if they're in a discordant relationship where their partner is positive and refuses to be initiated on HIV treatment early. I think microbicides are an important option for women in these types of relationships."
She's also excited by the development of what are called multi-purpose technologies -- two-in-one products that prevent both pregnancy and HIV transmission. She explains, "Women who are at risk of getting HIV infections are also likely to -- because they're young women -- have fertility control needs. Multi-purpose technologies are looking at combining contraceptives with HIV prevention."
Microbicides are not only being developed and tested for women. There are many different formulations being explored and tested for men who have sex with men as well. What stands out for Abdool Karim is the possibility of having HIV prevention products that meet every need and fill every gap.
"It's about ensuring that we have safe and effective products to meet different needs of different niche populations. To me, that's the ideal situation. It doesn't matter what's driving your risk -- what matters is that we have enough options that everybody can be protected."
Abdool Karim reminds us that, "Our work is not over. When we have scientific breakthroughs, they are moments we can treasure. But we have an obligation to continue our efforts until we have products that are available to people. The science is an important step one. The key is when we have the science, and the evidence, and the robustness -- how do we get that on a programmatic level and get it to the people who need it most? The more collective efforts there are, to address the remaining challenges that face us, at some point in our lifetime we will see the end of AIDS. But there's still a lot more we have to do before we can celebrate that moment."