HIV: Current Research
Open Access

The Evolution of Antiretroviral Therapy: An In-Depth Study of ART Regimens and their Effects on HIV Treatment

Neval Yurttutan Uyar^{* *}Correspondence: Neval Yurttutan Uyar, Department of Infectious Diseases, Ankara Yıldırım Beyazıt University, Ankara, Turkey, Email:

Author info »

Description

Anti - Retroviral Therapy (ART) is the mainbase of HIV treatment, aimed at managing the viral load, improving immune function, and enhancing the quality of life for individuals living with HIV. ART regimens consist of combinations of antiretroviral drugs that work synergistically to suppress HIV replication. This detailed explanation will cover the various classes of antiretroviral drugs, the structure of ART regimens, and the considerations involved in regimen selection.

Nucleoside Reverse Transcriptase Inhibitors (NRTIs) inhibit the reverse transcriptase enzyme, crucial for the replication of HIV. They are incorporated into the viral DNA, causing premature termination. Common NRTIs include: One of the earliest drugs used, effective but with potential for side effects like anemia. Widely used, particularly in combination with emtricitabine, but requires monitoring for renal function. Effective but requires testing for HLA-B*5701 allele due to hypersensitivity reactions. NNRTIs bind directly to reverse transcriptase, causing a conformational change has a long half-life and is effective but can cause neuropsychiatric side effects.Useful in treatment-experienced patients with drug resistance. Preferred for its more favorable side effect profile, but requires strict adherence due to low tolerance for missed doses. Protease Inhibitors (PIs) inhibit the HIV protease enzyme, preventing the cleavage of viral polyproteins into functional proteins. Notable PIs include: Used in low doses as a booster due to its potent effect on CYP450 enzymes. A combination known as lopinavir/ritonavir, effective but can cause gastrointestinal side effects. A potent PI with a high barrier to resistance, commonly used in combination regimens. INSTIs block the integration of viral DNA into the host genome.

Fusion inhibitors block the fusion of HIV with the host cell membrane. The primary drug in this class is used for treatmentexperienced patients with multi-drug resistance. These drugs block the C-C Chemokine Receptor Type 5 (CCR5) co-receptor, preventing HIV entry into cells. The main drug is Postattachment inhibitors block HIV from entering the host cell after initial binding. The primary drug is used for heavily treatment treatmentexperienced patients with multidrug- resistant HIV. ART regimens are generally constructed using combinations of drugs from different classes to maximize efficacy and minimize the risk of resistance. The standard ART regimen typically includes a common first-line regimen includes Tenofovir Disoproxil Fumarate (TDF) or Tenofovir Ala Fenamide (TAF) combined with and an INSTI such as Dolutegravir (DTG). This combination is preferred for its efficacy, tolerability, and low risk of resistance. Lamivudine (3TC) and Abacavir (ABC) paired with an Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI) like Rilpivirine (RPV) or a PI like Darunavir (DRV) can be used based on individual patient factors. Regimens with simpler dosing schedules and fewer pills are preferred for better adherence. Conditions such as renal impairment, cardiovascular disease, or psychiatric disorders can influence regimen choice. For treatment-naive patients, standard first-line regimens are typically effective. For treatment-experienced patients, resistance testing guides the choice of drugs to avoid ineffective therapies. Common side effects include gastrointestinal disturbances, lipid abnormalities, and bone density loss. Monitoring and management of these effects are essential.

ART drugs can interact with other medications, potentially altering their efficacy or increasing toxicity. For example, PIs and NNRTIs have significant interactions with other drugs metabolized by the liver. High adherence to ART is crucial for viral suppression and prevention of resistance. Fixed-dose combinations and once-daily regimens improve adherence. The side effect profile and patient tolerance to medications are significant factors in regimen selection. For example, DoluTe Gravir (DTG) is well-tolerated and has fewer side effects compared to older drugs. Regular monitoring of viral load and CD4 count is essential to assess the efficacy of ART and adjust treatment as needed. Additionally, routine screening for drug toxicity and side effects, such as renal and hepatic function tests, is necessary to ensure long-term safety.

Conclusion

ART regimens are critical in managing HIV infection and improving patient outcomes. Understanding the classes of antiretroviral drugs, the structure of regimens, and considerations in regimen selection is vital for optimizing treatment and ensuring effective long-term management.

Advances in ART continue to improve the lives of people living with HIV, with ongoing research aiming to enhance treatment options and ultimately find a cure.