Valacyclovir and acyclovir for suppression of shedding of herpes simplex virus in the genital tract.
BACKGROUND
Valacyclovir exhibits better oral absorption and higher, more prolonged serum concentrations than oral acyclovir. The efficacy of valacyclovir and acyclovir on genital herpes simplex virus (HSV) shedding was assessed in a double-blind, 3-period crossover trial.


METHODS
Sixty-nine immunocompetent participants with genital HSV-2 received oral valacyclovir, acyclovir, and matching placebo in random order for 7-week periods. Participants provided daily genital mucosal swabs for HSV detection by viral culture and polymerase chain reaction (PCR).


RESULTS
HSV was detected at least once in 62 (90%) participants by culture and in 68 (98%) by PCR. During placebo, the total HSV shedding rate was 15.4% of days by culture (PCR, 40.2%); the subclinical shedding rate was 6.6% by culture (PCR, 27.1%). Both antivirals were associated with lower HSV shedding by culture (relative risk [RR], 0.03 [95% confidence interval [CI], 0.01-0.07] for valacyclovir and RR, 0.05 [95% CI, 0.03-0.10] for acyclovir) and PCR (RR, 0.18 [95% CI, 0.12-0.26] for valacyclovir and RR, 0.20 [95% CI, 0.15-0.28] for acyclovir), compared with placebo. No significant differences in frequency and quantity of HSV were detected by PCR between the valacyclovir and acyclovir arms.


CONCLUSIONS
Although the suppression of viral replication is not complete, valacyclovir and acyclovir are highly effective in suppressing the frequency and quantity of genital HSV shedding.
Gupta
Rachna
R
Department of Medicine, University of Washington, Seattle, Washington 98122, USA. rachnag@u.washington.edu.
Wald
Anna
A
Krantz
Elizabeth
E
Selke
Stacy
S
Warren
Terri
T
Vargas-Cortes
Mauricio
M
Miller
Gerri
G
Corey
Lawrence
L
D000212:Acyclovir / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000627:therapeutic use*; D004279:DNA, Viral / Q000032:analysis; D004311:Double-Blind Method; D005260:Female; D005835:Genitalia / Q000821:virology*; D006558:Herpes Genitalis / Q000188:drug therapy* / Q000821:virology; D018258:Herpesvirus 2, Human / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000821:virology; D016896:Treatment Outcome; D000077483:Valacyclovir; D014633:Valine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D017201:Virus Shedding / Q000187:drug effects*
D000998:Antiviral Agents; D004279:DNA, Viral; D014633:Valine; D000077483:Valacyclovir; D000212:Acyclovir