Complete Antiretroviral Regimen: This single tablet contains a fixed-dose combination of three active ingredients: Tenofovir Disoproxil Fumarate (TDF) (A) 300 mg, Lamivudine (B) 300 mg, and Efavirenz (C) 600 mg.
Three-Drug Class Combination: It combines two nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs/NtRTIs) with a non-nucleoside reverse transcriptase inhibitor (NNRTI), providing a complete and robust antiretroviral regimen in a single pill.
Once-Daily Dosing: The formulation is designed for once-daily administration, which simplifies HIV treatment and helps improve patient adherence.
Broad Spectrum: This combination is highly effective against both the Human Immunodeficiency Virus (HIV) and the Hepatitis B virus (HBV), making it suitable for co-infected patients.
Advantages
Effective First-Line Therapy: This combination is a recommended and widely used first-line treatment for HIV-1 infection, demonstrating high efficacy in suppressing viral replication and improving immune function.
Improved Adherence: The single-pill, once-daily regimen significantly reduces the pill burden and complexity of treatment, which is a major factor in improving patient adherence and long-term treatment success.
Established Efficacy: The efficacy of this three-drug combination has been well-established through extensive clinical trials, and it is a cornerstone of global HIV treatment guidelines.
Dual Indication: The presence of TDF and lamivudine allows for the treatment of both HIV and chronic HBV, which is a significant advantage for patients who are co-infected.
Uses
HIV-1 Infection: This combination is a recommended first-line treatment for HIV-1 infection in adults and adolescents, providing a complete and effective regimen in a single tablet.
Treatment-Naïve Patients: It is widely used in patients who are new to antiretroviral therapy due to its high efficacy, good tolerability, and simplified dosing.
Chronic Hepatitis B (HBV) Infection: The TDF and lamivudine components provide effective treatment for chronic HBV, making this a suitable choice for patients coinfected with both HIV and HBV.
Prevention of Mother-to-Child Transmission: It is a key component of regimens used to prevent the transmission of HIV from mother to child during pregnancy and delivery.
Nature
Drug Classes: The tablet contains two different classes of drugs: NRTIs/NtRTIs (TDF and lamivudine) and an NNRTI (efavirenz).
Mechanism of Action:TDF and lamivudine inhibit the viral enzyme reverse transcriptase by terminating the DNA chain. Efavirenz also inhibits reverse transcriptase, but it does so by binding directly to the enzyme and changing its shape, making it non-functional.
Dual-Target Inhibition: By targeting the same viral enzyme (reverse transcriptase) through two different mechanisms, the combination provides a powerful and broad-spectrum attack on the virus, reducing the risk of resistance.
CNS Side Effects: A key characteristic of efavirenz is the potential for central nervous system (CNS) side effects, such as dizziness, insomnia, and vivid dreams. Taking the medication on an empty stomach at bedtime can help mitigate these effects.
Storage
Temperature: Store the tablets at controlled room temperature, typically between 20∘C to 25∘C (68∘F to 77∘F).
Protection: Keep the tablets in their original, tightly closed container, protected from light and moisture.
Administration: The medication should be taken on an empty stomach, preferably at bedtime, to reduce the absorption of efavirenz and minimize CNS side effects.
Patient Warning (HBV): Patients with HBV should be educated that abruptly stopping the medication can lead to a severe flare-up of their hepatitis, so they should not discontinue it without consulting their doctor.
