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CHICAGO —  New research in the treatment of AIDS has pointed to a possible cure, which could lead to the UN’s goal of ending the HIV/AIDS epidemic by 2030.

Research in human immunology, genomics, virology and structural biology has raised expectations for a successful vaccine strategy that could be an effective cure.

Results of the research are being discussed at the biennial HIV Research for Prevention (HIVR4P) conference in Chicago from October 17-21. More than 1,400 delegates from 41 countries are attending the event.

According to USAID, the AIDS pandemic continues to be a major global health issue. Although treatment rates have doubled in the past five years, the number of annual new infections with HIV has not decreased substantially.

In 2015, HIV infected more than two million people and killed more than one million around the world.

Sub-Saharan Africa remains the region most severely affected with 25 million adults and children living with HIV.

Recent modeling results show that even in the face of the massively expanded use of current treatment and prevention options, hundreds of thousands of people in low- and middle-income countries will be newly infected with HIV and die from AIDS for decades to come.

Given the scope of the epidemic, new biomedical tools to prevent HIV are essential, according to USAID.

An effective, well-adopted vaccine could prevent the majority of new annual HIV infections, thereby averting millions of infections and savings countless lives.

Professor Myron Cohen, director of the Institute for Global Health and Infectious Diseases at the University of North Carolina in the US, said the next 15 years would provide the field with opportunities for developing an array of HIV prevention tools, including the possible use of antibodies for HIV prevention, and the development of HIV vaccines based on an understanding of the mechanisms of action of the antibodies.

HIV prevention research is “on the move”, Cohen said, adding that ongoing studies would inform implementation of treatment for prevention and maximise benefits.

“Long-acting antiviral agents will serve as critical new tools for treatment and prevention of HIV,” he said, adding that ultimately new tools will lead to improve combination prevention of HIV.

HIVR4P co-chair Lynn Morris of South Africa’s National Institute for Communicable Diseases, said: “Vaccine research is embarking on two large clinical trials to test the ability of different types of antibodies to prevent HIV infection.”

“We also have a vigorous pipeline of new vaccine concepts and products, along with a more focused plan for getting them tested in humans much more quickly than ever before,” she added.

Another HIVR4P co-chair, Nelly Mugo of the Kenya Medical Research Institute, said that a global movement to crush the epidemic in women and girls required looking at HIV prevention technologies, implementation and behaviour issues together.

“Today we have new options in female-controlled HIV prevention such as pre-exposure prophylaxis (PrEP) and, perhaps soon, (dapivirine vaginal) rings. One of our biggest remaining challenges, and one that we expect to hear a lot about at the conference, is understanding how to make these new tools available to women and girls, and how to support them to use these tools and stay safe.”

Jeanne Marrazzo of the University of Alabama in Birmingham (US), who is also one of the HIVR4P co-chairs, said the field was realising that choice and flexibility were key to HIV prevention and to new options that can enhance both reproductive health and HIV and sexually transmitted infection prevention.

“Increasing access and adherence is also dependent on engaging potential users early and often, as new prevention products are developed and tested, to better understanding and address what they want and need to remain HIV-free,” she said.

Another HIVR4P co-chair, Thomas Hope of Northwestern University (US), said the conference supported collaboration and partnerships between researchers, advocates, scientists and policymakers focusing on vaccines, microbicides and other forms of prevention.

Such collaboration could lead to better, faster and more comprehensive responses to the epidemic, he said.

Interventions for adolescents

Dr Chewe Luo, associate director and programme division chief of HIV/AIDS Section at UNICEF, said that new HIV infections had declined rapidly among children aged zero to 14, but more slowly among adolescents aged 15 to 19 and young adults aged 20 to 24.

According to analysis of UNAIDS 2015 HIV and AIDS released in June, it was estimated that 1.8 million adolescents were living with HIV globally, including 80 per cent in sub-Saharan Africa.

“We have to need improve targeting and planning for effective combinations of prevention packages,” she said.

Ending AIDS in adolescents is an important contribution to ending AIDS by 2030 and ensuring broader sustainable development goals of ensuring health and well-being for all, at every stage of life, she said.

A differentiated and targeted approach is required for adolescents, and service packages must be cross-sectorial for adolescents, she added.

For instance, a combination HIV-prevention package for people who inject drugs includes HIV-test services and antiretroviral therapy; a condom lubricant programme; information on communication, empowerment, laws and rights of people who inject drugs; and clinical services, opoid-substitution therapy and needle-syringe exchange programmes.

This package is part of the UNAIDS’s fast-tracking combination prevention toward reducing new HIV infections to fewer than 500.000 by 2020.

Moreover, technology should be used in HIV intervention with adolescents, she said.

For example, the U-report, an interactive mobile phone and SMS-based programme, has been used to provide confidential counselling via SMS and chatting with adolescents in Zambia.

Currently, there are 2.1 million U-Reporters across the globe.

“We know that smarter investments targeted at biomedical, behavioural and structural interventions will decrease the number of new infections,” she said.

Susan Rosenthal of Columbia University (US) said that those who provide HIV intervention and other services to adolescents should have a better understanding of the implications of psychological development and decision-making.

Additional time should be built into clinic scheduling for counseling, she said.

More funds needed

A new report released at the second HIV Research for Prevention Conference documented 2015 funding, highlighting a decade of flat funding and its potential impact on continued innovation in the HIV-prevention research and development (R&D) field.

The Resource Tracking for HIV Prevention R&D Working Group’s 12th annual report with the title of HIV Prevention Research & Development Investments, and 2000-2015 Investment priorities to fund innovation in a challenging global health landscape, finds that funding for R&D of new and emerging prevention options decreased slightly in 2015.

This was due in part to decreases from the US public sector and a downswing in global philanthropic funding.

In 2015, funders invested a total of US $1.20 billion across R&D, down from US $1.25 billion in 2014, across eight key areas: preventive AIDS vaccines, microbicides, PrEP using antiretroviral drugs, treatment as prevention, Herpes simplex virus type 2 vaccines and operations research related to voluntary medical male circumcision, female condoms and prevention of vertical transmission.

Steady progress in R&D for AIDS vaccines, microbicides, PrEP using antiretroviral drugs and treatment as prevention confirms science’s critical role in providing solutions to end the HIV/AIDS epidemic.

Yet research for these badly needed solutions is in danger of being slowed or even sidelined by inadequate funding, according to a press release issued at the conference on September 19.

Luiz Loures, deputy executive director of UNAIDS, said that it was critical to scale up investments in HIV-prevention innovations, science and technology “to put us on the Fast-Track to ending AIDS by 2030”. 

The report also finds that investment is being made in all phases of the research pipeline but remains concentrated among a few large investors.

The US public sector (primarily via the National Institutes of Health) remained the largest global contributor at US$850 million, accounting for 70 per cent of total funding.

The US government and the Bill & Melinda Gates Foundation, the largest philanthropic funder, accounted for 81 per cent of all funding in 2015.  

A more diverse base of funders would increase the stability of R&D financing and cushion the impact if any of the major funders were to reduce their investments.

To improve continuity, the Resource Tracking for HIV Prevention R&D Working Group calls for a more balanced funding base, especially through support of new investment by European and low- and middle-income countries.

Mark Feinberg, president and CEO of International ADIS Vaccine Initiative, said there was strong momentum in research and development, and “we need to expedite the development of vaccine strategies and other new, biomedical prevention options that promise to be safe, accessible and effective for use throughout the world”.

“There must be adequate and sustained investment at all stages from early laboratory research and to clinical testing if we are to truly be able to contain the HIV pandemic and approach an end to AIDS,” he added.

There is great optimism for HIV prevention research.

Daily oral PrEP is gaining traction as a new prevention option in an increasing number of countries. An antiretroviral-based microbicide ring that showed modest efficacy earlier in 2016 will be further evaluated to determine its viability as a prevention option for women, and large-scale efficacy trials of an AIDS vaccine candidate and an injectable form of PrEP are slated to begin soon.

In addition, a novel proof-of-concept trial of antibody-mediated prevention is underway in several countries.

Many more promising candidates in earlier stages are progressing toward pre-clinical and clinical evaluation. 

Mitchell Warren, executive director of AVAC, a global advocate for HIV prevention, said that innovative science needed innovative funding.

“We need an expanded and more diverse global cadre of funders who will be involved in and dedicated to advancing HIV prevention R&D, including product delivery,” he said.

“And these investments need to ensure that new options like daily oral PrEP, and potentially the dapivirine vaginal ring, do not sit on the shelf unused because we don’t know how to effectively deliver them, and that future R&D better meets the needs and wants of those for whom the products are developed,” Warren added. — VNS