Emletra (Lopinavir & Ritonavir) is a combination drug that is generic to Kaletra. Its composition is a combination of two active ingredients: Lopinavir (200 mg) and Ritonavir (50 mg). Both of these substances are effective as a therapy for retroviruses, which include HIV.
Lopinavir is an HIV enzyme blocker. Inhibition of HIV proteases interferes with the synthesis of viral proteins, which contributes to the formation of an immature, weak and incapable of infection of the virus.
Ritonavir has some similarity to the HIV protease and shows little activity against human aspartyl protease.
In addition, Ritonavir by its actions increases the concentration of Lopinavir in human plasma. The combined effect of these two drugs in one tablet suppresses the multiplication of the virus in human blood.