Randomized Trial to Evaluate Suppressive Effect of High-Dose Valacyclovir Versus Once-Daily Valacyclovir on Persons With HSV-2

Screening Assessment Patients will be assessed for their eligibility to enter the study at a screening visit. After signing informed consent they will undergo a medical history and the following information will be recorded in the Case Report Form (CRF): * Demographic Data: Date of birth, sex, marital status, education and race * Previous antiviral medication taken * History of sexually transmitted infections and sexual history. * Women of childbearing potential will undergo a urine pregnancy test. Serologic samples for HSV-2 and HIV will be obtained. Part of the blood sample will also be used for safety labs. Start of Study Visit (Day 0) and Day 14, 28, 35, 42, 56, 70, and 77 Follow-Up Visits. Eligible patients will return to clinic to be given study drug and a patient diary card on which to record concomitant medications, signs and symptoms, and adverse experiences. The investigator will instruct the patient on daily home viral sample collection, taking the study drug, and completing the diary card. The patient will be instructed to return to clinic in 2 weeks, +/- 2 days. Medication compliance will be assessed at each visit using pill counts. Safety labs will be performed on day 14, 28, 35, 56, 70 and 77. Crossover Study Visit Prior To Washout Period (Day 35-41) Participants will not be given study drug or placebo during the 7-day washout period. Participants will not be required to obtain swabs during the washout period. Daily Home Viral Sample Collection Participants will collect swabs from the genital mucosa four times per day and store the samples in PCR media with preprinted labels. Women will swab the cervicovaginal, vulvar and perianal areas, and men will swab the penile and perianal. Every two weeks, they will return the samples to the Virology Research Clinic when they present for additional study drug and assessment. Final Study Visit (Day 77) At the final study visit at Day 77 or for premature discontinuation, the investigator will perform the activities at the regular study visits, with the exception of the dispensation of study drug.