About the Clinical Trials Networks
In 2006 these clinical trials networks were restructured to better address emerging domestic and international challenges to developing improved HIV treatment and prevention strategies by creating a more integrated, collaborative and flexible research structure. The six HIV/AIDS clinical trials Networks funded by the Division of AIDS (DAIDS) of the U.S. National Institutes of Health (NIH) include:
The clinical trials networks are also closely tied to these other HIV research efforts
AIDS Clinical Trials Group
The AIDS Clinical Trials Group (ACTG) is a multi-center clinical trials network comprised of U.S. and international clinical trials units that conduct translational and therapeutic research. The ACTG was first established in 1987 to pursue therapeutic research. The ACTG now conducts research in the U.S. and internationally; its highest research priorities are translational research and drug development and optimization of clinical management, including co-infection and co-morbidities. In collaboration with other clinical trials networks, the ACTG also pursues therapeutic vaccine research and development, the treatment of pregnant women, and the prevention of HIV infection. The ACTG conducts trials that address specific areas of HIV therapeutic research in collaboration with other NIH Institutes, including the National Cancer Institute, the National Institute of Dental and Craniofacial Research and the National Institute of Neurological Disorders and Stroke.
Translational research and drug development efforts in the ACTG are aimed at the evaluation of:
- anti-HIV compounds with novel mechanisms of action/new targets, including small molecule entry inhibitors, uncoating inhibitors, integrase inhibitors, integrase inhibitors, and maturation inhibitors;
- new classes of drugs with unique and improved features, such as different resistance profiles or better pharmacologic or toxicologic properties; and
- new therapies for individuals with co-infections, focusing on tuberculosis, hepatitis C, and human papillomavirus (HPV). In addition, the network focuses on the integration of immune based therapies into treatment regimens, emphasizing mechanisms of antiviral effect and immune reconstitution, and the evaluation of new hypotheses generated by pathogenesis studies.
In the area optimization research, the ACTG evaluates:
- the effectiveness of new regimens or new treatment strategies, particularly those that incorporate agents with novel mechanism of action; and
- therapies and therapeutic strategies for treating co-infections and complications, including prophylaxis, acute and maintenance treatment, and immune-based therapies. In addition, the ACTG strives to optimize therapies on the basis of safety, adherence, resistance, durability of response, and prevention of transmission.
HIV Prevention Trials Network
The HIV Prevention Trials Network (HPTN) is a worldwide collaborative clinical trials network that develops and tests the safety and efficacy of primarily non-vaccine interventions designed to prevent the transmission of HIV. The HPTN was first established in 2000, building on the work of the HIV Network for Prevention Trials (HIVNET).
The HPTN research agenda is focused primarily on the use of antiretroviral therapy; treatment and prevention of sexually transmitted infections; treatment of substance abuse, particularly injection drug use; and behavioral risk reduction interventions to reduce HIV transmission and acquisition.
HPTN studies evaluate new HIV prevention interventions and strategies in populations and geographical regions that are bearing a disproportionate burden of infection. This is intended to facilitate rapid scale-up and to have the greatest possible impact on the pandemic. In addition, the HPTN has refined and expanded its expertise in the development and validation of tools for the early detection of HIV infection. To maximize their quality and benefits, all HPTN studies are conducted in close partnership with the community.
HIV Vaccine Trials Network
The HIV Vaccine Trials Network (HVTN) is an international collaboration of scientists searching for an effective and safe HIV vaccine. The HVTN's mission is to facilitate the process of testing preventive vaccines against HIV/AIDS, conducting all phases of clinical trials, from evaluating experimental vaccines for safety and the ability to stimulate immune responses, to testing vaccine efficacy. The HTVN’s priorities include:
- performing clinical trials in populations throughout the world to determine if a vaccine candidate or vaccine regimen “qualifies” for further efficacy evaluation;
- designing and conducting a program of HIV vaccine efficacy trials that provides rigorous testing of critical scientific concepts for the development of HIV vaccines and ultimately delivers sufficient characterization of the safety and efficacy of a candidate vaccine to enable its licensure;
- developing and maintaining a clinical trials network that will provide an objective and transparent platform to evaluate the safety, immunogenicity and efficacy of candidate HIV vaccines;
- advancing the laboratory and statistical approaches in clinical trial design that will define potential correlates of protection within HIV vaccine efficacy trials; and
- developing standardized risk reduction counseling methods that are applicable across all HVTN sites.
The HVTN includes community members in the governance and conduct of clinical trials. Involvement is promoted through community representation on HVTN scientific and operational committees, and through consultations with trial volunteers and community leaders at conferences and other gatherings of stakeholders in HIV prevention treatment and care. In addition, HVTN strives to develop and support collaborations with other relevant NIH networks, federal agencies, and non-governmental research organizations to advance the highest quality HIV vaccine research, with optimal efficiency and cost-effectiveness.
International Maternal Pediatric Adolescent AIDS Clinical Trials group (IMPAACT)
IMPAACT is a merger of the Pediatric AIDS Clinical Trials Group and the Perinatal Scientific Working Group of the HPTN. Together, these two networks have designed and performed clinical trials that have yielded data to set the standards of care for HIV-infected children and for the interruption of vertical transmission throughout the world. The PACTG has been a joint effort between the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institute of Child Health and Human Development (NICHD) since 1993, and NICHD will continue to work collaboratively with IMPAACT. Specifically, IMPAACT’s mission is to significantly decrease the mortality and morbidity associated with HIV disease in children, adolescents, and pregnant women. Toward this end, IMPAACT is developing and evaluating safe and cost effective approaches for the interruption of mother-to-infant transmission; evaluating treatments for HIV-infected children, adolescents, and pregnant women, including treatment and prevention of co-infections and co-morbidities; and evaluating vaccines for the prevention of HIV sexual transmission among adolescents. On both a domestic and international scale, IMPAACT’s research plan encompasses NIAID’s six areas of highest scientific priority including the prevention of mother to child transmission (PMTCT), translational research and drug development, optimization of clinical management, including co-morbidities, and vaccine.
International Network for Strategic Initiatives in Global HIV Trials (INSIGHT)
INSIGHT is a merger of two existing clinical trials research groups, ESPRIT (Evaluation of Subcutaneous Proleukin® in a Randomized Clinical Trial) and the CPCRA (Terry Beirn Community Programs for Clinical Research on AIDS). This uniquely large network is comprised of over 250 clinical sites in 25 countries. INSIGHT will conduct studies in the area of optimization of clinical management of HIV, including HIV-disease and non-HIV associated co-morbidities. The INSIGHT research agenda addresses key issues compromising the health of HIV-infected individuals. The ESPRIT study to determine whether raising CD4 counts by cycles of interleukin-2 in subjects receiving ART confers clinical benefit compared to ART alone, and the STALWART study to determine whether cycles of interleukin-2 with or without cycles of ART will permit delay in commencing continuous ART are continuing. A new study is being developed, based upon their unexpected findings in the SMART study, that individuals interrupting ART experienced a higher rate of both HIV and non-HIV disease progression, especially cardiovascular events: START, addressing when to start therapy for asymptomatic individuals with higher CD4+ T cell counts. This key pilot study will be conducted over the next two years and may then be expanded to a full clinical endpoint trial, if feasibility and preliminary surrogate marker results are favorable. These trials will help inform clinical practice.
Microbicide Trials Network (MTN)
The mission of the Microbicide Trials Network (MTN) is to reduce the sexual transmission of HIV through the development and evaluation of microbicide products, and it will carry out its mission through a strong network of expert scientists and investigators from domestic and international sites. The MTN conducts scientifically rigorous and ethically sound clinical trials that will support licensure of topical microbicide products. The current generation of microbicide candidates may only provide partial protection from HIV infection. Nonetheless, given the dynamics of HIV infection in the developing world, it is likely that even partial protection may translate to significant community benefits for prevention. Some of the scientific questions that are being addressed through MTN studies include placebo-controlled assessment of the safety and acceptability of candidate microbicide products and potential dosing regimens (tenofovir gel [daily versus coitally-associated use] and Vivagel® are currently in such trials); assessment of the acceptability, safety and efficacy of different prevention strategies (topical microbicide and oral pre-exposure prophylaxis) in the same population of women using tenovofir gel, oral Truvada® and oral tenofovir disoproxil fumarate (each compared to a matched placebo); new formulation technologies as they become available, such as the vaginal ring; the safety of vaginal microbicides in pregnancy; the safety of vaginal microbicides for rectal use; and the long-term virological sequelae of exposure to reverse transcriptase inhibitor microbicides in subjects who have chronic HIV infection or who seroconvert during an MTN study. Studies currently underway provide critical infrastructure, expertise and data to evaluate 2nd generation products. The depth and breadth of the preclinical pipeline and promising animal model efficacy data provide reason to be optimistic that identification of a safe and effective microbicide is realistic.