A validated HPLC-MS method for quantification of the CCR5 inhibitor maraviroc in HIV+ human plasma

Maraviroc is a CCR5 inhibitor approved in 2007 for treatment of therapy experienced adult patientsinfected with CCR5-tropic HIV-1 virus. International guidelines for HIV therapy indicate a plasma con-centration cutoff of maraviroc for response. We developed and validated a new HPLC-MS method toquantify maraviroc concentrations in human plasma. 6,7-Dimethyl-2,3-di(2-pyridyl)quinoxaline wasused as internal standard and added to 100 L of plasma. Samples were then treated with 500 L ofacetonitrile for the protein precipitation procedure. An analytical T3 Atlantis column (150 mm × 4.6 mmi.d.) with a particle size of 5 m was used to separate the compounds and ions were detected at m/z 257.5and 313.3 for maraviroc and quinoxaline respectively. The calibration curve was linear up to 2500 ng/mL.The mean recovery of maraviroc was 89.1%. All validation data results were in accordance to Food andDrug Administration and European Medicines Agency requirements. The HPLC-MS method reported herecould be used routinely to monitor plasma concentrations of maraviroc in HIV-infected patients.