Model of pre-exposure prophylaxis against HIV forecasts benefits, potential cost-effectiveness

February 10, 2009

NIAID Media Availability

WHAT: For every two people who begin treatment for HIV infection globally, five others become newly infected. Therefore, preventing new HIV infections is the foremost strategy for ending the HIV/AIDS epidemic. One potential prevention strategy involves giving antiretroviral drug regimens to people who are at high risk for HIV to protect them from infection. Important questions about this experimental approach, known as pre-exposure prophylaxis (PrEP), remain unanswered, including, Could PrEP cut the lifetime risk of HIV infection? Would PrEP be cost-effective?

A new mathematical model of PrEP use in U.S. populations at high risk for HIV infection takes these and other questions into account and predicts the prevention strategy could substantially reduce the lifetime risk of HIV infection. According to the model, the cost-effectiveness of PrEP could vary substantially depending on the age of the target population, their risk behaviors, the annual rate of new HIV infections in the target population, and the efficacy and cost of antiretroviral PrEP drugs. These findings are reported by a team of scientists led by A. David Paltiel, Ph.D., of Yale University, and supported by the National Institute of Allergy and Infectious Diseases (NIAID), the National Institute of Mental Health and the National Institute on Drug Abuse, all part of the National Institutes of Health.

Dr. Paltiel says his team's model is the first to establish performance benchmarks that clarify the clinical, epidemiologic and economic circumstances under which PrEP would represent good patient care, good public health and good value.

To create their model, the researchers made several conservative assumptions: 1) PrEP is 50 percent effective; 2) the target population is American men who have sex with men who average 34 years of age; 3) 1.6 percent of this population becomes newly infected with HIV annually; and 4) the antiretroviral drugs (tenofovir and emtricitabine) cost $9,000 per year. With these parameters, the model predicts PrEP would cut the lifetime risk of HIV infection from 44 percent to 25 percent. However, the life expectancy of the target population from the time after beginning PrEP would increase by less than a year (from 39.9 years to 40.7 years) and PrEP would not be cost-effective by current U.S. standards. Yet with modest improvements in the efficacy of antiretrovirals used preventively, more realistic estimates of their cost (potentially as low as $900 per year), or a target population that is younger and at higher risk, the model predicts PrEP might be as cost-effective as other widely recommended public health and medical interventions in the United States. With large improvements in these parameters, the potential benefits of PrEP could be substantial, according to the model. For example, assuming PrEP will be 90 percent effective leads the predicted lifetime risk of HIV infection to fall from 44 percent to 6 percent.

NIH/National Institute of Allergy and Infectious Diseases

---

---

	MMHIV: Medical Management of HIV Infection (2012 Medical Management of HIV Infection, 16th Edition) by M.D John G. Bartlett (Author), M.D., M.P.H. Joel E. Gallant (Author), Pharm.D. Paul A. Pham (Author) MMHIV: The Medical Management of HIV Infection is provided as a resource for physicians and other health care professionals in providing care and treatment to patients with HIV/AIDS. The 2011-2012 edition of Medical Management of HIV Infection reflects substantial changes in the treatment of patients with HIV infection and AIDS since the previous edition was published in 2010. This edition includes 214 tables and more than 900 references to publications or presentations made in 2010 and 2011, reflecting the authors' efforts to keep abreast of new developments by attendance at major scientific conferences and by systematic review of 42 relevant journals. Recommendations presented here are based largely on US federal guidelines for antiretroviral therapy for adults, pregnancy management,...
	Johns Hopkins HIV Guide 2012 by Joel E. Gallant (Author) Based On The Same Award-Winning Content As The Johns Hopkins POC-IT Center Online Database, The Johns Hopkins HIV Guide 2012 Is The Most Up-To-Date HIV Treatment And Management Resource On The Market. Written By Dr. Joel E. Gallant, World Renowned Expert In The Field Of HIV And Infectious Disease, This Concise And Well-Organized Medical Reference Is Broken Down Into Several Modules, Including: Diagnosis And Evaluation, Treatment Options, Resistance And Complications, Prophylaxis And Antiretroviral Drug Summaries. Johns Hopkins HIV Guide 2012 Contains The Most Current, Relevant And Evidence-Based Information On HIV And AIDS. Selected Topics Include: • Antiretroviral Therapy Adverse Effects • HIV Antibody Testing • Important Genotype-Resistant Patterns • Musculoskeletal And...
	The First Year: HIV: An Essential Guide for the Newly Diagnosed by Brett Grodeck (Author), M.D. Daniel S. Berger M.D. (Foreword) This supportive resource explores the next generation of HIV/AIDS drugs and also includes new research on HIV and crystal meth, as well as new insights for the hardest hit population — African Americans.
	Healing HIV: How to Rebuild Your Immune System by Jon D. Kaiser (Author)
	Couples of Mixed HIV Status: Clinical Issues And Interventions. (Haworth Psychosocial Issues of HIV/AIDS) by R Dennis Shelby (Author), Nancy L Beckerman (Author) Examine the unique emotional challenges and issues that face couples of mixed HIV status today! Previous books on this subject—mostly written in the days when HIV/AIDS was considered a fatal rather than a chronic disease—focused on end-of-life issues. However, Couples of Mixed HIV Status: Clinical Issues and Interventions addresses the unique emotional challenges facing today’s couples of mixed HIV status and provides a conceptual framework for assessment and intervention. The book offers examples of how to apply emotionally focused couple therapy to help them work through issues including disclosure, the fear of HIV transmission, shifts in emotional intimacy, family planning, betrayal, mistrust, and uncertainty. This unique work, its knowledge base, and the interventions...
	100 Questions and Answers About HIV and AIDS by Joel Gallant (Author)
	The Guide to Living with HIV Infection: Developed at the Johns Hopkins AIDS Clinic (A Johns Hopkins Press Health Book) by John G. Bartlett (Author), Ann K. Finkbeiner (Author) The Guide to Living with HIV Infection is the most complete source of medical, emotional, social, and practical advice available for those infected with HIV and their loved ones. Developed at the Johns Hopkins AIDS Clinic, the guide provides essential information for making decisions about treatment and testing in a world transformed by new research and pharmacotherapy.In this thoroughly updated sixth edition, Dr. John Bartlett and Ann K. Finkbeiner address the latest information about risks of transmission, viral mutations that confer drug resistance, and new, rapid, HIV testing. They offer guidelines for Highly Active Antiretroviral Therapy (HAART), a therapy protocol that has dramatically increased life expectancy for HIV-positive people. They describe how to follow HAART and when to...
	COMMUNITY-ACQUIRED PNEUMONIA IN IMMUNOCOMPROMISED PATIENTS: Opportunistic infections to consider in differential diagnosis Patients with HIV infection ... in primary care. (Postgraduate Medicine) by JTE Multimedia Differential diagnosis can be extensive in immunocompromised patients who present for evaluation of apparent community-acquired pneumonia. In addition to the usual pathogens seen in the general population, many opportunistic organisms of widely differing classes may require consideration. Here, the authors have chosen to focus on four pathogens that may be overlooked in the primary care setting. Epidemiologic, clinical, and therapeutic points are highlighted. Original Publication Date: January 2003
	PRIMARY HIV INFECTION: Early diagnosis and treatment are critical to outcome (Postgraduate Medicine) by JTE Multimedia It is now apparent that early identification of primary HIV infection is important, because events occurring in early disease may predict how fast a patient progresses to AIDS. However, as Dr Schacker points out, diagnosis is not easy at this stage. This article describes clinical features and laboratory tests to help primary care physicians make a timely diagnosis and discusses current recommendations for therapy. Original Publication Date: October 1997