Maraviroc is a new drug in the treatment of HIV infection, which targets other action sites than the existing anti-retroviral drugs.
Maraviroc inhibits the formation of the binding complex at the surface of the host cell when the virus tries to enter. The viral surface protein gp120 binds the CD4 receptor on the T-cell. A second essential signal is binding of gp120 to the co-receptor CCR5 of CXCR4. Completion of the binding complex makes it possible for protein gp41 to form a pore in the membrane of the T-cell. Viral components can now penetrate the host cell. Maraviroc is a specific CCR5 antagonist which prevents CCR5-tropic HIV-1 entry. HIV-1 using the CXCR4 as co-receptor is not affected by maraviroc.