maraviroc + raltegravir

Maraviroc and raltegravir are two distinct antiretroviral medications used in the treatment of HIV-1 infection, each with a unique mechanism of action. When used together, they form part of combination antiretroviral therapy regimens. ## Maraviroc Maraviroc is a CCR5 receptor antagonist that works by preventing HIV entry into host cells. It selectively binds to the human chemokine receptor CCR5 on the cell membrane, preventing the interaction between HIV-1 glycoprotein 120 and CCR5-tropic HIV-1[1][6][10]. This mechanism blocks viral entry at an early stage of the HIV lifecycle. The drug is marketed under the brand name Celsentri[4] and was developed by Pfizer[6]. Maraviroc is primarily metabolized by CYP3A4 and has an absolute oral bioavailability of 23% at a 100 mg dose and 33% at a 300 mg dose[6]. It has a half-life of 14-18 hours and is approximately 76% bound to human plasma proteins[6]. Common adverse effects include diarrhea, nausea, headache, dizziness, cough, insomnia, rash, weakness, muscle spasms, and back pain[1]. ## Raltegravir Raltegravir is an HIV-1 integrase inhibitor that prevents viral DNA from integrating into the host cell genome[1]. By inhibiting the catalytic activity of the integrase enzyme, raltegravir blocks a crucial step in HIV replication, preventing the virus from making copies of itself[1]. The drug is marketed under the brand name Isentress[4][7][9] and is manufactured by Merck. Raltegravir is primarily metabolized by UGT1A1[2]. It's available in several formulations including film-coated tablets, chewable tablets, and oral suspension[9]. Common side effects of raltegravir include gastrointestinal problems, asthenia, dizziness, pruritus, lipodystrophy, hyperhidrosis, and arthralgia[1]. ## Combination Use When used together, maraviroc and raltegravir target different stages of the HIV lifecycle. A pharmacokinetic study showed that co-administration of these drugs resulted in a 20% decrease in mean Cmax and 14% decrease in mean AUC of maraviroc, and a 33% decrease in mean Cmax and 37% decrease in mean AUC of raltegravir[2]. However, these changes were not considered clinically relevant, and no dose adjustment is necessary when the drugs are used together[2]. The combination was generally safe and well-tolerated in healthy subjects[2]. Both drugs are used as part of combination antiretroviral therapy regimens for treatment-experienced patients with HIV-1 infection[3]. The long-term safety profile of both drugs has been evaluated, with maraviroc demonstrating general safety in treatment-experienced participants for more than 5 years[8]. Similarly, raltegravir has shown efficacy and tolerability regardless of gender or race in diverse populations of adult patients with HIV-1 infection[7].

Brand names

IsentressSelzentry

Other names

None