Used acyclovir or valacyclovir during study follow-up.HSV-2 prevalenceOf the 2,499 participants, 1383 (55.3 ) tested negative for HSV-2 at baseline, 892 (35.7 ) tested positive, 223 (8.9 ) had indeterminate tests, and one test was not done. Of the 223 with indeterminate tests at baseline, 114 (51.1 ) tested positive for HSV-2 infection at some point during follow-up. Factors associated with testin
No differences by randomization group in the proportion of participants with 1 STI examination during which a perianal ulcer (FTC/TDF 3.5 vs. placebo 4.7 , P = 0.37) or groin ulcer (FTC/TDF 2.5 vs. placebo 1.9 , P = 0.51) was identified; results were similar after excluding participants with a positive syphilis rapid plasma reagin test at the same visit. However, symptoms that prompted STI exam
Nversion to determine whether there were differences in ulcer occurrence by randomization group in the absence of study drug. All analyses were conducted in SAS 9.3 or Stata 12.Results Study participantsCharacteristics of the 2,499 iPrEx participants have been described previously. [13] Briefly, all participants were born male and 313 (13.0 ) identified as transgender or as women. The mean age at
Aseline by age group at enrollment, while Figure 1b shows HSV-2 incidence during follow-up by age group at enrollment. HSV-2, herpes simplex virus type 2. doi:10.1371/journal.pone.0091513.gDiscussionIn this analysis of participants in the iPrEx trial of daily oral FTC/TDF PrEP, we found no association between FTC/TDF and incidence of HSV-2 infection, even after accounting for actual use of FTC/TDF
T among participants living in Peru (46.0 ), Brazil (37.8 ), and Ecuador (37.3 ), with lower prevalence among participants living in Thailand (6.4 ), South Africa (17.6 ), and the United States (27.1 ; P,0.001). Randomization group was not associated with HSV-2 prevalence at baseline (P = 0.44). In multivariable analysis, all factors remained significantly associated with HSV-2 prevalence with the
No differences by randomization group in the proportion of participants with 1 STI examination during which a perianal ulcer (FTC/TDF 3.5 vs. placebo 4.7 , P = 0.37) or groin ulcer (FTC/TDF 2.5 vs. placebo 1.9 , P = 0.51) was identified; results were similar after excluding participants with a positive syphilis rapid plasma reagin test at the same visit. However, symptoms that prompted STI exam
No differences by randomization group in the proportion of participants with 1 STI examination during which a perianal ulcer (FTC/TDF 3.5 vs. placebo 4.7 , P = 0.37) or groin ulcer (FTC/TDF 2.5 vs. placebo 1.9 , P = 0.51) was identified; results were similar after excluding participants with a positive syphilis rapid plasma reagin test at the same visit. However, symptoms that prompted STI exam
Lcer was identified, and 5.6 had 1 STI examination during which a groin ulcer was identified after HIV seroconversion, and thus after stopping study drug. The proportions with each type of ulcer did not differ between participants in the FTC/TDF arm and participants in the placebo arm. Finally, the iPrEx protocol did not use the HSV-2 test manufacturer's suggested cutoffs for indeterminate (IR