June 5, 2006
The human immunodeficiency virus (HIV), the cause of AIDS, has now infected more than 65 million people worldwide, of whom 25 million have died, according to estimates of the Joint United Nations Programme on HIV/AIDS (UNAIDS). AIDS is the deadliest pandemic of our generation and one of the worst in history. In the year 2005 alone, approximately 4.1 million people worldwide, half of them women, became infected with HIV, and about 2.8 million individuals with HIV/AIDS died. More than 95 percent of these infections and deaths occurred in developing countries, most of which are also burdened by other significant health challenges. In these nations, HIV/AIDS threatens not only human welfare, but social, political and economic stability as well.
In the United States, an estimated one million people are living with HIV infection, and 40,000 new infections occur each year. HIV infection rates continue to climb among women, racial and ethnic minorities, young homosexual men, individuals with certain addictive disorders and people over 50 years of age. To date, HIV/AIDS has killed more than half a million people in our country.
The magnitude of the HIV/AIDS pandemic requires a robust, multi-faceted and sustained global response from all sectors of society. At the U.S. National Institutes of Health (NIH), we are committed to accelerating the research that will help end the scourge of HIV/AIDS. The NIH effort represents the largest public investment in HIV/AIDS research anywhere in the world. In fiscal year 2006, $2.9 billion has been appropriated for NIH AIDS-related research. The resources devoted to HIV/AIDS research by our many partners in the research enterprise also have been significant.
The returns on these investments have been extraordinary, and built on NIH-supported advances in fields such as immunology and virology that occurred in the 1960s and 1970s. Within three years of the first reported AIDS cases in 1981, the virus that causes the syndrome, HIV, was discovered. In 1984, a sensitive and specific diagnostic test for antibodies to HIV was developed and used to screen the U.S. blood supply, making it extremely safe since 1985. Scientists around the world illuminated the structure and genetic organization of HIV and made rapid advances in understanding its disease-causing mechanisms. These advances in turn facilitated the rapid development and testing of potent anti-HIV drugs and guidelines for the use of these medications. Combination antiretroviral therapy has played a major role in the dramatic decreases in HIV-related morbidity and mortality where these medications have been used. In addition, certain antiretroviral drug regimens dramatically reduce the risk of HIV transmission from mother to child. The risk factors associated with HIV transmission have been well defined, providing the foundation for prevention efforts. In virtually all developed nations and in a growing number of developing countries, prevention programs have proven effective in slowing the spread of HIV infection, although rates of new infections, even in countries considered to be "success stories," continue at an unacceptably high level.
In addition, our AIDS research investment is providing dividends for people with other diseases. AIDS-related research is helping to unravel the mysteries surrounding many other infectious, malignant, neurologic, autoimmune and metabolic diseases. AIDS research has led to an entirely new paradigm for the design, development and testing of drugs to treat other viral infections. For example, the drug 3TC, developed to treat HIV/AIDS, is now a widely used and effective therapy for chronic hepatitis B infection. Drugs developed to prevent and treat AIDS-associated opportunistic infections also provide benefit to patients undergoing cancer chemotherapy or receiving anti-transplant rejection therapy. In addition, AIDS research is providing a new understanding of the relationship between viruses and cancer.
Despite numerous advances in HIV/AIDS research, the pandemic continues to undermine lives, communities and societies. Clearly, much remains to be accomplished in AIDS research, both in terms of the scientific and medical challenges of HIV disease and with regard to the logistical and operational challenges of making HIV therapies, prevention services and other interventions available to poor countries.
For example, important challenges remain in the area of therapeutics research. Many patients receiving antiretroviral therapy do not fare well on their treatment regimens due to the development of drug resistance, drug toxicities and side effects. The increasing incidence of metabolic disorders, cardiovascular complications, major organ dysfunction and physical changes associated with current antiretroviral drugs underscores the critical need for new and better treatment regimens. Improved regimens also are needed to treat HIV co-infections such as hepatitis B and C, as well as other opportunistic infections, in order to reduce drug interactions associated with concomitant treatment regimens, as well as problems with adherence to complicated treatment regimens. A high priority of NIH-sponsored AIDS therapeutics research continues to be the development of drugs and therapeutic regimens that are less toxic and have fewer side effects, limit the development of drug resistance, enter viral reservoirs to inhibit viral replication, facilitate easier adherence and are less expensive and more readily accessible.
NIH also reaffirms our commitment to the development of the next generation of prevention modalities, including topical microbicides, which individuals could use to protect themselves against HIV infection. The ultimate defeat of HIV/AIDS will require a multi-pronged effort but will be difficult, if not impossible, without a safe and effective HIV vaccine. Over the past five years, NIH has devoted approximately $2 billion to HIV/AIDS vaccine research.
The development of an HIV vaccine is a complex research challenge because HIV is unusually well equipped to elude immune defenses, as exemplified by its ability to vary extensively, to persist in viral reservoirs and to eventually overcome the immune system. NIH has now conducted or initiated approximately 80 Phase I and two Phase II clinical trials of nearly 50 vaccine candidates, individually or in combination, in collaboration with our partners in academia and industry. Important progress is being made, with promising vaccine candidates advancing rapidly into clinical trials. Among these is a "global" HIV vaccine -- targeted to multiple HIV subtypes found worldwide -- which has moved into the second phase of clinical testing.
On this sobering anniversary, we remember the millions who have died over these past 25 years, those who continue to live with HIV/AIDS and fight the disease every day and the many thousands who have helped us to further science by participating in AIDS clinical trials. We also are reminded that we must do more, collectively, to slow the scourge of HIV/AIDS at home and abroad: as individuals, protecting ourselves and our loved ones from HIV and working to eliminate stigma and discrimination; as clinicians, utilizing the most current and effective regimens to treat people with HIV disease; as friends and caregivers, helping to ease the suffering of those living with HIV/AIDS; as researchers, developing newer and better tools to help those infected with HIV and to prevent future infections; and as policy-makers and activists, helping to bring the benefits of critical research advances in treatment and prevention to those who need them most.
For additional information, NIH has established a Web site with documents and links related to the NIH response to HIV/AIDS: www.25yearsofaids.oar.nih.gov.
Dr. Zerhouni is director of the National Institutes of Health in Bethesda, Maryland. Dr. Whitescarver is associate director for AIDS Research and director of the Office of AIDS Research. Dr. Fauci is director of the National Institute of Allergy and Infectious Diseases.