title: Baseline Predictors of High Adherence to a Coitally Dependent Microbicide Gel Based on an Objective Marker of Use: Findings from the Carraguard Phase 3 Trial.
abstract: A randomized, placebo-controlled, efficacy trial of Carraguard was unable to demonstrate a reduction in women's risk of HIV infection, which may have been due, in part, to low adherence (gel used in 42 % of vaginal sex acts, on average). A secondary analysis was undertaken to understand baseline factors associated with high adherence (gel used in ≥85 % of sex acts). Women who reported ≥1 vaginal sex act, returned ≥1 opened applicator, and had ≥1 conclusive post-enrollment HIV test (N = 5990) were included. Adherence was estimated as the ratio of average weekly applicator insertions (based on a dye stain assay indicating vaginal insertion)/average weekly sex acts (by self-report). Multivariate logistic regression modeling indicated that coital frequency, site, contraception, and partner age difference had a significant impact on adherence. Women reporting >1 and ≤2 vaginal sex acts per week, on average, were half as likely to be adherent as those reporting 1 vaginal sex act per week or less [adjusted odds ratio (AOR): 0.48; 95 % CI 0.38-0.61]; women from the Western Cape had one-third the odds of being adherent compared to women from KZN (AOR: 0.31; 95 % CI 0.23-0.41); compared to women using injectable contraception, women using any other or no method were more likely to be adherent (AOR: 1.30; 95 % CI 1.04-1.63); and women who had a larger age gap from their partners were more likely to be adherent (AOR: 1.03; 95 % CI 1.01-1.05; p = 0.001). Despite low adherence, overall, 13 % of participants achieved nearly perfect adherence, indicating a potential niche for a coitally dependent microbicide. More research is needed on the impact of sexual patterns and HIV risk perception on product acceptability and adherence to improve counseling in ongoing trials and when products are eventually introduced.
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA. bfriedland@popcouncil.org.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Friedland
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.
authors.forename: Marie
authors.initials: M
authors.lastname: Stoner
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Chau
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.
authors.forename: Marlena Gehret
authors.initials: MG
authors.lastname: Plagianos
authors.affiliation: Population Council, Johannesburg, South Africa.
authors.forename: Sumen
authors.initials: S
authors.lastname: Govender
authors.affiliation: South African Medical Research Council, Durban, South Africa.
authors.forename: Neetha
authors.initials: N
authors.lastname: Morar
authors.affiliation: University of Cape Town, Cape Town, South Africa.
authors.forename: Lydia
authors.initials: L
authors.lastname: Altini
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.|Memorial Sloan Kettering Cancer Center, New York, NY, USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Skoler-Karpoff
authors.affiliation: Setshaba Research Centre, Soshanguve, South Africa.
authors.forename: Khatija
authors.initials: K
authors.lastname: Ahmed
authors.affiliation: South African Medical Research Council, Durban, South Africa.
authors.forename: Gita
authors.initials: G
authors.lastname: Ramjee
authors.affiliation: Setshaba Research Centre, Soshanguve, South Africa.
authors.forename: Constance
authors.initials: C
authors.lastname: Monedi
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.
authors.forename: Robin
authors.initials: R
authors.lastname: Maguire
authors.affiliation: Population Council, 1 Dag Hammarskjold Plaza, New York, NY, 10017, USA.|Department of Obstetrics and Gynecology, University of Helsinki, Helsinki, Finland.
authors.forename: Pekka
authors.initials: P
authors.lastname: Lähteenmäki
mesh_terms: D000293:Adolescent; D000328:Adult; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000009:adverse effects; D003075:Coitus; D005260:Female; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D055118:Medication Adherence; D008875:Middle Aged; D015999:Multivariate Analysis; D012725:Sexual Behavior; D013019:South Africa / Q000453:epidemiology; D014622:Vaginal Creams, Foams, and Jellies / Q000008:administration & dosage* / Q000009:adverse effects; D055815:Young Adult
chemical_list: D000890:Anti-Infective Agents; D014622:Vaginal Creams, Foams, and Jellies
keywords: Adherence; Applicator test; Biomarker; Carraguard; Dye stain assay; Microbicide; South Africa