One of NIAID’s greatest success stories is that its research led to the development of numerous antiretroviral drugs to treat HIV/AIDS turning what was once a uniformly fatal disease into a manageable chronic condition for many. NIAID is working to find new and more effective therapeutic products, drug classes, and combinations as well as safe and effective treatments for dangerous AIDS-related co-infections, such as hepatitis, malaria, and tuberculosis.
Treatment of HIV Infection
In the early 1980s when the HIV/AIDS epidemic began, people with AIDS were not likely to live longer than a few years. Today, there are 31 antiretroviral drugs (ARVs) approved by the Food and Drug Administration to treat HIV infection. These treatments do not cure people of HIV or AIDS. Rather, they suppress the virus, even to undetectable levels, but they do not completely eliminate HIV from the body.
There are six major types of drugs used to treat HIV/AIDS. Called antiretrovirals because they act against the retrovirus HIV, these drugs are grouped by how they interfere with steps in HIV replication. Read more about types of HIV/AIDS antiretroviral drugs.
Although some people maintain that treatment with zidovudine (AZT) has compounded the AIDS epidemic (Duesberg, 1992), published reports of both placebo-controlled clinical trials and observational studies provide data to the contrary. Read more about AZT and AIDS.
HIV/AIDS Therapeutics Research
NIAID is focused on discovery and development of novel and more effective therapies that can extend and improve the quality of life for people infected with HIV/AIDS and associated co-infections and complications, including strategies for potential eradication or sustained remission of HIV infection. The goal is to identify new drugs that are less toxic with fewer side effects, promote better adherence, and are readily accessible, particularly in resource-limited settings. Promising medicines are tested in human clinical trials to determine whether they are safe and effective.
Several therapeutic agents have been developed to treat HIV and its co-infections and to prevent the transmission of HIV. However, the emergence of drug resistance and the need for simpler regimens that allow better adherence mandate research for better treatments that can improve patient outcomes and control the epidemic. The NIAID HIV/AIDS therapeutics research agenda is guided by the National Institutes of Health (NIH) Office of AIDS Research, the entity responsible for the overall scientific, budgetary, legislative, and policy elements of all AIDS research sponsored by NIH. The major areas of research within the NIAID therapeutic research agenda include drug discovery, preclinical drug development, clinical research, and co-infections.
The identification of viral and cellular drug targets is essential for fueling the drug development pipeline. Early drug discovery efforts concentrated on a relatively small number of viral targets such as HIV reverse transcriptase (an enzyme that catalyzes the synthesis of viral DNA within infected cells from the RNA template carried by infectious virions) and HIV protease (an enzyme that cleaves and processes viral precursor proteins allowing virion maturation). Treatment regimens containing combinations of reverse transcriptase and protease inhibitors, commonly known as highly active antiretroviral therapy, or HAART, revolutionized the treatment of people with HIV by markedly lowering viral load and decreasing the incidence of AIDS-associated opportunistic infections. Many patients receiving HAART nevertheless suffer metabolic abnormalities and drug toxicities, have difficulty adhering to the complex drug regimens, and develop strains of HIV resistant to therapy. To address these concerns, additional potential therapies using novel formulation technologies or targeting other steps in the viral replication process are being evaluated and are in various stages of preclinical and clinical investigation. Read more about HIV/AIDS drug discovery research.
A new therapeutic agent with demonstrated activity in cell culture and in animal efficacy models requires many additional studies to convert it from a promising lead into a pharmaceutical agent suitable for evaluation in clinical trials. These product development (or "translational") activities are designed to generate the necessary pharmaceutical-grade materials and preclinical data needed to support submission of an Investigational New Drug application to the Food and Drug Administration (FDA). The types of preclinical studies required include scale-up synthesis of the therapeutic agent, development of analytical assays to detect and quantitate the therapeutic agent and its metabolites, development and manufacture of dosage formulations, and animal pharmacology and toxicology. Many of these studies require compliance with current FDA regulations regarding Good Manufacturing Practices and Good Laboratory Practices. NIAID administers contracts to conduct many of these translational activities for new therapeutic agents to treat HIV and its co-infections. Read more about HIV/AIDS preclinical drug development.
Once a new therapeutic agent or strategy has been thoroughly studied in preclinical studies, the information generated typically is submitted to the Food and Drug Administration (FDA) as part of an Investigational New Drug (IND) application. Evaluation of the therapeutic agent or strategy in human subjects can begin once FDA has approved the IND application. Read more about HIV/AIDS therapeutics clinical research.
HIV-infected people are at increased risk of diseases caused by infection with infectious agents such as Mycobacterium tuberculosis and other mycobacteria, hepatitis C, hepatitis B, Pneumocystis carinii, cryptococci, fungi, and human cytomegalovirus. While diseases caused by many of these pathogens are less common today in HIV-infected patients receiving highly active antiretroviral therapy (HAART), co-infection with tuberculosis (TB), hepatitis C virus (HCV), and hepatitis B virus (HBV) remain significant causes of illness and death among people living with HIV, especially in regions where the risk of co-infection is high. Read more about research on HIV co-infections.
Hepatitis C can be a chronic condition that leads to liver failure, and treatments often haven’t worked for patients who are also co-infected with HIV. Thanks to research led by NIAID and Gilead Sciences, new therapies are now available that can cure even complicated cases of hepatitis C without serious side effects. Read more about the path to a cure for hepatitis in people with HIV to learn how these discoveries were made and what they mean for patients around the world.
Drug Adherence and Drug Resistance
People infected with HIV who take antiretroviral treatments sometimes find it difficult to adhere to their drug regimens. This may be because it can be hard to take several medicines each day and at different times or because of the unpleasant side effects caused by some medicines, such as nausea and vomiting.
However, when patients fail to take their medicines, HIV has an opportunity to create more variations of itself, including strains that are resistant to antiretroviral drugs. Therefore, it is important for patients to continue taking their medicines as prescribed by their healthcare providers.