Antiretroviral

Antiretroviral Therapy

Antiretroviral therapy (ART) is the cornerstone of treatment for Human Immunodeficiency Virus (HIV) infection. It involves the use of multiple antiretroviral drugs to suppress the virus and stop the progression of the disease.

History

The development of antiretroviral drugs began in the late 1980s, with the approval of zidovudine (AZT) as the first antiretroviral drug in 1987. Since then, the field has expanded significantly, with the introduction of new classes of drugs and combination therapies.

Mechanism of Action

Antiretroviral drugs work by targeting different stages of the HIV life cycle. The main classes of antiretroviral drugs include:

• Nucleoside Reverse Transcriptase Inhibitors (NRTIs): These drugs mimic the natural nucleosides used by reverse transcriptase to synthesize viral DNA, thereby terminating the DNA chain.
• Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs): These drugs bind to reverse transcriptase and inhibit its activity directly.
• Protease Inhibitors (PIs): These drugs inhibit the protease enzyme, preventing the maturation of viral particles.
• Integrase Inhibitors: These drugs block the integrase enzyme, preventing the integration of viral DNA into the host genome.
• Entry Inhibitors: These drugs prevent the virus from entering host cells by blocking the fusion or binding process.

Treatment Regimens

ART typically involves a combination of three or more antiretroviral drugs from at least two different classes. This approach is known as Highly Active Antiretroviral Therapy (HAART). The goal is to achieve and maintain an undetectable viral load, which helps prevent the progression to AIDS and reduces the risk of transmission.

Side Effects

While ART is highly effective, it can cause side effects, which vary depending on the specific drugs used. Common side effects include nausea, diarrhea, fatigue, and metabolic changes. Long-term use can lead to complications such as lipodystrophy, cardiovascular disease, and bone density loss.

Adherence

Adherence to ART is crucial for its success. Poor adherence can lead to drug resistance, treatment failure, and increased risk of transmission. Strategies to improve adherence include patient education, simplified dosing regimens, and support services.

Global Impact

ART has transformed HIV from a fatal disease to a manageable chronic condition. It has significantly reduced HIV-related morbidity and mortality and improved the quality of life for millions of people worldwide. However, access to ART remains a challenge in many low- and middle-income countries.

Future Directions

Research is ongoing to develop new antiretroviral drugs with improved efficacy, safety, and convenience. There is also a focus on finding a cure for HIV and developing effective vaccines.

See Also

• HIV/AIDS
• Zidovudine
• Protease Inhibitors
• Integrase Inhibitors

References

• World Health Organization: HIV Treatment
• Centers for Disease Control and Prevention: HIV Treatment