Valaciclovir to Prevent Transmission of Herpes Simplex Virus

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

This study will evaluate the effectiveness of the drug valaciclovir in preventing transmission of genital herpes from an infected to an uninfected sexual partner. Genital herpes is caused by the herpes simplex virus 2 (HSV-2), or, infrequently herpes simplex virus 1 (HSV-1). Valaciclovir prevents the herpes virus from multiplying and may also reduce its transmission between partners. Couples 18 years of age and older in which one partner is infected with HSV-2 (source partner) and the other is not (susceptible partner), may be eligible for this study. Candidates will be screened with blood tests for routine laboratory studies and to verify the presence or absence of HSV-2 or HSV-1 infection. Participants will give a medical history, undergo a physical examination, including genital examination, and receive counseling on safer sex practices and how to recognize signs and symptoms of a possible first episode of genital herpes. Source partners will also be counseled on transmission of genital herpes, and susceptible partners will be interviewed about their sexual history and practices. The source partner will be randomly assigned to take either a 500-mg tablet of valaciclovir or placebo (a pill with no active ingredient) daily for 8 months. All participants will be given diary cards to complete for a month-the source partner will record any drug side effects and the susceptible partner will record any signs or symptoms of possible HSV infection. Participants will be seen in the clinic once a month for 8 months. At these visits, source partners will 1) return unused study medication and the completed diary card; 2) discuss any adverse drug side effects experienced in the last month; 3) review medications other than the study drug taken in the last month; 4) undergo counseling on safer sex practices, transmission of genital herpes, and recognizing signs and symptoms of a first episode of genital herpes; and 5) review symptoms and recurrences of genital herpes experienced during the last month. During the final visit, they will also provide a blood sample for routine testing and possible use in future studies. Susceptible partners will 1) have a blood sample drawn for HSV testing; 2) undergo safer sex counseling; 3) review any symptoms experienced over the last month; 4) be interviewed about sexual exposure and practices; and 5) return the completed diary card. Source partners who have a recurrence of genital HSV while on the study will be asked to have their lesions cultured and will be offered open-label valaciclovir treatment. Susceptible partners who contract genital herpes from the source partner during the study will have a genital examination to verify a fist episode of genital herpes and will receive 10 days of open-label treatment with valaciclovir. Cultures will be taken from the mouth and genitals, current medical conditions will be reviewed, blood samples will be drawn on treatment days 1 and 10, and treatment side effects will be reviewed on days 5 and 10. At the end of the study, infected partners will be offered a 12-month course of valaciclovir, one 500-mg tablet daily. Participants will be followed in the clinic once every 3 months to provide blood samples, return unused study medication and the diary card, discuss any drug side effects, review medications taken besides the study drug, and review symptoms or recurrences of genital herpes. All participants will be asked to complete a questionnaire for gathering information about people with genital herpes and people at risk for the infection.

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Last update posted Mar 3, 2008 · Synced Sep 4, 2026

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