Antiretroviral Agent: Raltegravir is an integrase strand transfer inhibitor (INSTI), a potent class of drugs used for the treatment of Human Immunodeficiency Virus Type 1 (HIV-1).
Standard Adult Dosing: The 400 mg film-coated tablet is the standard oral dosage form for adults, typically administered twice daily as part of a combination antiretroviral therapy (ART) regimen.
Combination Therapy: Raltegravir is not used as a monotherapy. It is always prescribed with other active antiretroviral agents to provide a complete and effective treatment plan and prevent the development of viral resistance.
Film-Coated Tablet: The tablet is film-coated and must be swallowed whole. It should not be crushed, broken, or chewed due to potential changes in its pharmacokinetic profile.
Advantages
Novel Mechanism of Action: As the first-in-class integrase inhibitor, Raltegravir targets a unique step in the HIV lifecycle, making it effective against virus strains that have developed resistance to other drug classes, such as NRTIs and NNRTIs.
Rapid Viral Load Reduction: Raltegravir has been shown to rapidly reduce viral load to undetectable levels, which is crucial for improving immune function and preventing disease progression.
Low Potential for Drug Interactions: Raltegravir’s metabolism is primarily through glucuronidation, not the cytochrome P450 (CYP450) system. This results in a low potential for drug-drug interactions, making it easier to co-prescribe with other medications.
Effective in Treatment-Experienced Patients: It is highly effective in patients who have failed previous antiretroviral regimens due to its unique mechanism and activity against multidrug-resistant HIV.
Uses
HIV-1 Infection: Indicated for the treatment of HIV-1 infection in adults and adolescents weighing at least 25 kg, in combination with other antiretroviral agents.
Treatment-Naïve and -Experienced Patients: Raltegravir is approved for use in both patients who are new to HIV treatment and those who have been previously treated.
Post-Exposure Prophylaxis (PEP): It is a key component of PEP regimens to prevent HIV infection following a potential exposure.
Pregnancy: Raltegravir is a recommended antiretroviral for use in HIV-positive pregnant women due to its established safety and efficacy.
Nature
Integrase Inhibitor: Raltegravir belongs to the integrase inhibitor class of antiretroviral drugs.
Mechanism of Action: It works by binding to the active site of the viral enzyme integrase. This enzyme is essential for integrating the HIV DNA into the host cell’s DNA, a crucial step in the viral replication cycle.
Inhibition of Viral Replication: By inhibiting integrase, Raltegravir prevents the viral DNA from being inserted into the host cell’s genome, thereby blocking the production of new viral particles.
Metabolism & Elimination: Raltegravir is primarily metabolized by UDP-glucuronosyltransferase 1A1 (UGT1A1). This unique metabolic pathway contributes to its low drug interaction profile. It is mainly eliminated via the fecal route.
Storage
Temperature: Store Raltegravir tablets at a 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 tablets can be administered with or without food. However, it is crucial to follow the prescribed twice-daily dosing schedule consistently.
Co-administration: When co-administered with rifampin, the dose of raltegravir must be adjusted to 800 mg twice daily. Patients should not use aluminum- or magnesium-containing antacids with raltegravir.
