Tom Harmon

In this guest post Tom Harmon, senior policy analyst at the International AIDS Vaccine Initiative (IAVI), highlights a new analysis exploring the critical role of a vaccine in ending AIDS. Photo credit: IAVI When we talk about ending AIDS, what do we mean? The last dozen years have brought tremendous strides in reducing new HIV infections in low- and middle-income countries (LMICs), expanding lifesaving treatment to almost 16 million people living with HIV, and implementing programs to address the epidemic in populations at especially high risk, including women and girls. But we must continue to push for progress in treatment and prevention. The 2 million new infections in 2014 remain far too high, and almost 60 percent of people needing treatment are not getting it. So, when we talk about conclusively and durably ending AIDS and ensuring that it does not bounce back, our experience with other infectious diseases shows that a preventive vaccine will be necessary. The global effort to develop an AIDS vaccine has also recently experienced significant successes and steps forward. For example, we’ve never before seen such a diversity of approaches and partners, with follow-on trials based on the first candidate to show modest efficacy slated to begin later this year in South Africa, exciting new insights toward generating protective antibodies against HIV, and promising approaches toward inducing cellular immune responses that could control HIV infection. Still, there are more far-reaching questions we’re asked today by policymakers, advocates, communities, and even researchers themselves: What would the global response look like if an AIDS vaccine was available? How effective would it need to be? Would it be cost-effective and affordable? A new article, published in PLoS ONE aims to answer some of these crucial questions. The result of a collaboration between IAVI, Avenir Health, and AVAC that builds on work by UNAIDS, this model specifically explores a vaccine’s potential value in terms of preventing HIV infections in LMICs. We analyzed a vaccine’s potential impact depending on how well the world can achieve ambitious HIV and AIDS program objectives, how effectively it can prevent HIV infection, and how it can add to a response that also includes pre-exposure prophylaxis and treatment as prevention. We also looked at cost scenarios to see how a vaccine would stand up to cost-effectiveness criteria used by the World Health Organization to guide the introduction of new health technologies. Despite the potential for today’s tools to have a substantial impact on the epidemic, our results show that a vaccine is a critical piece to ending AIDS. Under our base scenario, a vaccine of 70 percent efficacy with strong uptake would reduce HIV infections in LMICs by 44 percent in its first 10 years and by 65 percent in 25 years, ultimately averting tens of millions of infections and saving millions of lives. Reduction of new annual HIV infections with PrEP, TasP and vaccination added individually and in combination to the Full Scale-up of IFE between 2015 and 2070. A vaccine would be impactful and cost-effective even at lower efficacy levels and costs far higher than many of today’s vaccines. Increasing a vaccine’s efficacy, ensuring it protects for a longer period of time, reducing the number of doses, lowering the cost of a dose, and more effectively rolling it out are all factors that would increase a vaccine’s impact and its value. Such a vaccine could cut the number of people needing treatment in half by the year 2070, and eventually reduce the total cost of fighting AIDS in LMICs even when the additional cost of implementing the vaccination program is included. While these data provide a powerful illustration of a vaccine’s potential value, we acknowledge and welcome discussions of its intrinsic limitations, which reflect the areas the AIDS vaccine field and future program implementers will need to tackle as we research, develop, and ultimately deliver a vaccine to the people who need it most. Such an analysis helps explore the parameters that determine the medical and economic impact and value of a future AIDS vaccine as part of the comprehensive HIV and AIDS response. This data can be a useful guide for research portfolio decisions as new candidates move closer to efficacy trials. In many ways these projections are as much a vaccine development and delivery “to-do list” as they are a crystal ball for what the future holds. A few weeks ago, the US Centers for Disease Control and Prevention organized a Grand Rounds presentation on how models are used to guide pandemic responses. This interesting panel was closed by Dr. Richard Hatchett, chief medical officer and deputy director for strategic sciences at the US Biomedical Advanced Research and Development Authority, who cited modeler Steven Bankes’ use of campfires as an analogy for predictive models, in that their value goes beyond their primary deliverable (be it light, heat, or data), as they just as importantly provide a “gathering place” for discussion between stakeholders. Our new model can perform just such a dual function, adding valuable context for a vaccine’s future role in ending the AIDS epidemic which has ravaged so many communities, while stimulating conversations and new questions on what we need to do in the real world to turn theory to impact.

In this guest post Tom Harmon, senior policy analyst at the International AIDS Vaccine Initiative (IAVI), and Anna Forbes, a globally recognized advocate for women’s HIV prevention needs, discuss a new piece proposing how HIV prevention research and development (R&D) for women and girls can better align with programs to improve their health and well-being. Photo: PATH/Doune Porter Around the time a girl in sub-Saharan Africa reaches the age of fifteen her risk of HIV infection skyrockets from two to five times that of boys her age. This high incidence stands in contrast to the increasing success of the global HIV and AIDS response, which has seen global infections reduced year after year and millions more people living with HIV and AIDS able to access lifesaving antiretroviral treatment (ART). It’s not news that HIV and AIDS has increasingly impacted young women and girls in sub-Saharan Africa. Fortunately, this past year may be remembered as a year the world stepped up to the challenge. The 2015 launch of the US$500 billion dollar DREAMS program (Determined, Resilient, Empowered, AIDS-free, Mentored, and Safe women) by the US President’s Emergency Plan for AIDS Relief (PEPFAR), the Bill & Melinda Gates Foundation, and Girl Effect aims to leverage high-impact interventions to reduce new HIV infections by 40 percent in girls and women in ten countries in Africa by 2017. Even as this program was scaling up, the World Health Organization expanded HIV treatment guidelines to cover all individuals living with HIV and AIDS regardless of the extent to which the virus has impacted their immune system status. This expansion will include many women and girls not previously covered. These near-term efforts should make a substantial difference in women’s lives. It’s also encouraging that pre-exposure prophylaxis (PrEP)—just a few years after formal approval as an HIV prevention tool—is incorporated in DREAMS. We know that the optimal HIV prevention toolbox for women and girls is one that can be customized to meet each person’s individual needs. Continuing to expand that toolbox with other new HIV prevention options, including HIV-blocking microbicides and a preventive HIV vaccine, can ultimately break the back of the rising epidemic among women and girls and the global epidemic in the long-term. Research to develop and deliver effective new prevention options doesn’t take place in a vacuum—it must take into consideration the wider needs of the women and girls it seeks to ultimately protect. To that end, IAVI recently published a new policy brief “Research and Development of New Biomedical HIV Prevention Tools for Women and Girls: Combating the global AIDS epidemic through a more empowered response in sub-Saharan Africa” that summarizes findings and recommendations for improved HIV prevention research with and for women and girls. Our work highlights challenges to better align HIV prevention research for women and girls with the needs and realities of their lives. For instance, a recent issue of the Journal of Acquired Immune Deficiency Syndromes highlighted the relatively low participation of women in HIV vaccine trials (38 percent) and AIDS treatment trials (19 percent), which limits our understanding of how effective an intervention is for women and girls. And, we know that if research taking place in a community doesn’t ensure some ongoing community benefit once a trial is completed, it can discourage participation by women in future trials. Fortunately, some of these essential elements are already being addressed. Positive results in microbicides research have correlated to excellent efforts to incorporate end user perspectives in product profiles. The Ragon Institute’s FRESH study links girls and young women highly vulnerable to HIV with programs that build job skills, attacking one of the drivers of poverty while also identifying early HIV infection and quickly enrolling women living with HIV and AIDS in ART programs. Keeping HIV prevention R&D in touch with the renewed focus on fighting HIV and AIDS among women and girls in sub-Saharan Africa is critical to the long-term goal of ending AIDS. We’re proud to be part of an HIV prevention research community that is already making strides to improve the lives of women and girls while building the scientific knowledge necessary to bring new tools to the fight. Doing right BY communities will ensure that the fruits of our work will be more effective IN those communities. Pockets of high incidence are devastating in any population and put overall progress at risk. Infectious diseases spread in the wider world when they are not stopped where they hit the hardest. This further underscores the importance of a sustained commitment to improving and expanding programs that reduce HIV incidence in women and girls and adding new interventions that women and girls can use to protect themselves. None of this is possible if we can’t assure women and girls with a strong HIV response that engages them, listens to them, and then implements the programs and research necessary to make this feminized epidemic yesterday’s news.