<qa>  How many visits will the study take place every 2 months?Participants in this study will be followed for 2 years or until antiretroviral therapy is modified or discontinued. Study visits will occur every 2 months, for a total of 14 visits. Study visits will include a patient interview and blood tests to measure the breadth and magnitude of the HIV-specific CD4 and CD8 cell responses as a function of viral load, viral replicative capacity, drug resistance phenotype, T cell turnover, and thymic function. 