Adherence and its measurement in phase 2/3 microbicide trials.
Ontology highlight
ABSTRACT:
SUBMITTER: Tolley EE
PROVIDER: S-EPMC2944966 | biostudies-literature | 2010 Oct
REPOSITORIES: biostudies-literature
Publications
Adherence and its measurement in phase 2/3 microbicide trials.
Tolley Elizabeth E EE Harrison Polly F PF Goetghebeur Els E Morrow Kathleen K Pool Robert R Taylor Doug D Tillman Stephanie N SN van der Straten Ariane A
AIDS and behavior 20101001 5
Adherence optimization and measurement have emerged as critically challenging issues for clinical trials of topical microbicides. Although microbicide trials have routinely collected adherence data, their utilization in trial design, implementation, and interpretation has been inconsistent. Drawing on data-driven presentations from several focused meetings, this paper synthesizes lessons from past microbicide trials and provides recommendations for future trials of microbicide and other HIV prev ...[more]
Similar Datasets
Project description:BackgroundInterpretation of clinical trial results testing vaginal microbicide gels for HIV prevention depends on participant adherence. Prior to the era of antiretrovirals, microbicide trials collected adherence data via self-report, and trials typically reported trial population adherence as overall averages in primary results manuscripts. This study first sought to determine if different patterns of adherence from three trials of vaginal microbicide gels could be identified, using self-reported data and if so, how those patterns compare across trials. The second objective was to explore which individual-level factors were associated with different adherence patterns.MethodsData from the following three clinical trials of vaginal microbicides were used for this study: HIV Prevention Trials Network (HPTN) 035 testing PRO 2000 and Buffergel, the Microbicides Development Programme (MDP) 301 testing PRO 2000, and the Population Council's Carraguard study, testing Carraguard gel. Latent Class Analysis (LCA) was used to identify longitudinal patterns of adherence using self-reported data about gel use. Multinomial multivariable logistic regression was used to estimate relative risk-ratios for factors which were independently associated with different latent adherence trajectories within each trial, and compared across trials.ResultsIncluded in this analysis are 2,282 women from HPTN 035 (age 17-56 years), 6238 women from MDP 301 (age 16-75 years), and 6039 women from Carraguard (age 16-73 years). Using LCA, 3-4 different patterns of gel adherence were identified in each trial; these patterns were similar across the trials. Factors associated with adherence patterns were identified in all trials. Older age was associated with the adherence trajectory that consistently reported gel use in three trials. Participant-reported negative reaction of partners to the gel was associated with trajectories that reported less consistent adherence in two trials. A greater number of baseline-reported sex partners or sex acts was associated with trajectories which reported less consistent adherence in some trials. Trial site location was associated with membership of trajectories in all trials.ConclusionLCA was able to identify patterns of microbicide gel adherence in clinical trials that used self-reported data. Key factors associated with patterns of adherence in this study were participant age, clinical trial site location, and partner reaction to the study gel. These findings, in particular, age and perceived partner reaction to the method, are consistent with results from other clinical trials and programmatic rollout of biomedical HIV prevention methods for women in Africa. This study contributes to the body of evidence that women need more support to navigate power dynamics within their relationships with men so that they can successfully use HIV prevention methods.
| S-EPMC9098085 | biostudies-literature
Project description:High adherence is key to microbicide effectiveness. Here we provide a description of adherence interventions and the adherence rates achieved in the CAPRISA 004 Tenofovir gel trial. Adherence support for the before-and-after dosing strategy (BAT 24) was provided at enrolment and at each monthly study visit. This initially comprised individual counselling and was replaced midway by a structured theory-based adherence support program (ASP) based on motivational interviewing. The 889 women were followed for an average of 18 months and attended a total of 17,031 monthly visits. On average women reported five sex acts and returned 5.9 empty applicators per month. The adherence rate based on applicator count in relation to all reported sex acts was 72.2 % compared to the 82.0 % self-reported adherence during the last sex act. Adherence support activities, which achieve levels of adherence similar to or better than those achieved by the CAPRISA 004 ASP, will be critical to the success of future microbicide trials.
| S-EPMC4017080 | biostudies-literature
Project description:Low adherence in vaginal microbicide clinical trials for HIV prevention has impeded interpretation of trial results and hindered evaluation of potentially efficacious HIV prevention gels. Understanding the underlying reasons why women join trials and their barriers to product use can support identification of ways to improve adherence and its reporting. Eight focus group discussion workshops were conducted with 46 former microbicide trial participants in Durban, South Africa and Mwanza, Tanzania. Participants provided feedback on why women join trials, the barriers to using study gel and reporting adherence accurately, and how clinical trial design can be improved to support better adherence and its reporting. Women join microbicide trials for a number of important reasons such as healthcare and financial reimbursement. Fear of adverse effects from the investigational product was the most important reason why participants reported not using the gel. The key reason for inaccurate reporting of gel use was fear of removal from the trial. Participants made concrete suggestions for improving microbicide trial design such as applicator use testing and real time feedback, improving education to participants about how trials answer their research questions, and improving transparency and clarity about study procedures. Participants also gave feedback on an innovative trial design with a non-randomised arm. Identifying HIV prevention products for women requires better understanding of the lives of women asked to join these trials, and application of that understanding to microbicide trial design. This study has demonstrated that participants and research teams can work collaboratively to design clinical trials that meet needs of both the research and of participants.
| S-EPMC7790400 | biostudies-literature
Project description:BackgroundTo date different vaginal gel microbicides have been evaluated in phase 2b/3 trials, but none have demonstrated effectiveness for preventing HIV infection. Failure to demonstrate effectiveness however does not necessarily indicate that a product is truly inefficacious, as several sources of efficacy dilution may compromise our ability to identify products that may have been truly efficacious.MethodsFor four individual sources of dilution, we describe the dilution mechanisms and quantify the expected effectiveness. An overall expected effectiveness that combines all sources of dilution in a trial is derived as well.ResultsUnder conditions that have been observed in recent microbicide trials, the overall expected effectiveness assuming an active gel with true efficacy of 50% and 75% are in the range of [16%; 33%] and [28%; 50%], respectively, when considering the four major sources of dilution. In contrast the diluting effect due to adherence alone (assuming an adherence of 80%) leads to higher expected effectiveness, 40% and 60% assuming an active gel with true efficacy of 50% and 75%, respectively. Individual sources of dilution may demonstrate a small effect when evaluated independently, but the overall dilution effect in a trial with several sources of dilution can be quite substantial.ConclusionCurrently planned phase 2b/3 microbicide trials of new candidate vaginal microbicides are not immune from these shortcomings. A good understanding of dilution effects is necessary to properly interpret microbicide trial results and to identify products worthy of further development and evaluation. Greater attention should be devoted to reducing and assessing the impact of efficacy dilution and to carefully selecting the effect size in the design of future trials.
| S-EPMC2768687 | biostudies-literature
Project description:This analysis compares self-reports of product use with objective measures of non-adherence-quarterly plasma dapivirine levels and monthly residual dapivirine (DPV) levels in used rings-in MTN-020/ASPIRE, a phase 3 trial of a monthly DPV vaginal ring among women aged 18-45 years in Malawi, South Africa, Uganda and Zimbabwe. For participants on active product (N = 1211) we assessed self-reported monthly non-adherence, as measured by (1) whether the ring was ever out, and out for ≥ 12 h in the previous month and, (2) by a self-rating scale assessing ability to keep the vaginal ring inserted, and compared the self-reports to two biomarkers of non-use separately and as a composite measure. For this analysis, a plasma DPV value ≤ 95 pg/ml and residual ring ≥ 23.5 mg were used to classify non-adherence (i.e. the ring never being in the vagina the previous month). Compared to self-reports, non-adherence was found to be substantially higher for the composite measure as well as its two components, an indication that ring removal was likely underreported in the trial. The discrepancy between the self-report measure of ring outage and the composite indicator was greater for those aged 18-21 than for those older, evidence that younger women are more likely to underreport non-adherence. Despite underreporting of non-adherence, self-reports of the ring never being out were significant in predicting the composite objective measure. Furthermore, the association between the self-rating scale and the objective measure was in the expected direction and significant, although 11% of those 18-21 and 7% of those 22+ who rated their ability to keep the ring inserted as good, very good or excellent in the 4 weeks prior to exit were considered non-adherent according to the objective measure. This analysis indicates that while self-reports are significantly associated with objective measures of adherence in the ASPIRE trial, they were inflated-more so by those younger-and therefore may have limited utility identifying those who have challenges using products as directed. ClinicalTrials.gov number NCT01617096.
| S-EPMC6374159 | biostudies-literature
Project description:Over the last decade several phase III microbicides trials have been conducted in developing countries. However, laboratories in resource constrained settings do not always have the experience, infrastructure, and the capacity to deliver laboratory data meeting the high standards of clinical trials. This paper describes the design and outcomes of a laboratory quality assurance program which was implemented during a phase III clinical trial evaluating the efficacy of the candidate microbicide Cellulose Sulfate 6% (CS) [1].In order to assess the effectiveness of CS for HIV and STI prevention, a phase III clinical trial was conducted in 5 sites: 3 in Africa and 2 in India. The trial sponsor identified an International Central Reference Laboratory (ICRL), responsible for the design and management of a quality assurance program, which would guarantee the reliability of laboratory data. The ICRL provided advice on the tests, assessed local laboratories, organized trainings, conducted supervision visits, performed re-tests, and prepared control panels. Local laboratories were provided with control panels for HIV rapid tests and Chlamydia trachomatis/Neisseria gonorrhoeae (CT/NG) amplification technique. Aliquots from respective control panels were tested by local laboratories and were compared with results obtained at the ICRL.Overall, good results were observed. However, discordances between the ICRL and site laboratories were identified for HIV and CT/NG results. One particular site experienced difficulties with HIV rapid testing shortly after study initiation. At all sites, DNA contamination was identified as a cause of invalid CT/NG results. Both problems were timely detected and solved. Through immediate feedback, guidance and repeated training of laboratory staff, additional inaccuracies were prevented.Quality control guidelines when applied in field laboratories ensured the reliability and validity of final study data. It is essential that sponsors provide adequate resources for implementation of such comprehensive technical assessment and monitoring systems.ClinicalTrials.gov NCT00153777 and Current Controlled Trials ISRCTN95638385.
| S-EPMC2965094 | biostudies-literature
Project description:AimThe current research aims to systematically review the rates of adherence reported in randomised controlled clinical trials of acamprosate. It also sought to determine the reliability of the adherence monitoring and measurement methods used in these trials.MethodsThe protocol for this review was pre-registered (PROSPERO: CRD42021230011). A search of the literature was conducted using OVID MEDLINE, Embase and PsycINFO from database inception to January 2021. Randomised controlled trials with a minimum sample size of 10 per treatment arm that compared the efficacy of acamprosate with placebo or other active medication in adults with a diagnosis of alcohol dependence were included. Data on rates of adherence, methods of measurement and monitoring of adherence was extracted from eligible studies independently in duplicate by two reviewers. A weighted mean adherence rate was calculated. The reliability of adherence monitoring methods was determined by calculating an adherence-assurance score based on the adherence monitoring method used. Risk of bias was assessed using the Cochrane Risk of Bias Tool.ResultsFifteen studies met the eligibility criteria involving 4,450 participants (2,480 participants in the placebo arms). A mean adherence rate of 88% (54.2-95.0%) was reported across studies that reported the percentage of medication taken. A mean adherence rate of 84.9% (56.4-91.3%) was reported for trials that reported the percentage of participants taking more than 80% of medication prescribed. There is low confidence in the methods used to monitor adherence with all clinical trials having a low adherence-assurance rating. Risk of bias was judged to be high for all included studies.ConclusionsAdherence to acamprosate in clinical trials can be poor with low confidence in the methods used to measure it. Adherence rates therefore might not be accurate, which has implications for determining the efficacy of acamprosate.
| S-EPMC8812903 | biostudies-literature
Project description:Use of HIV prevention methods may vary for women by types of sexual partners. In a microbicide safety and effectiveness trial (HPTN 035) differences in adherence to a microbicide study gel were compared between women with new versus ongoing partnerships over time. 1,757 women in the three HPTN 035 trial's arms completed the Follow-up Partner Status (FPS) questionnaire at their last study visit. Women married at baseline were asked if they had the same husband, new husband or new partner. Unmarried women were asked if they had changed partners or married. Self-reported gel adherence during the last sex act was compared at each quarterly visit between women with ongoing versus new partners. High gel adherence was compared with low gel adherence (85-100 vs. <85 % of last vaginal sex acts reported with gel use, respectively) in multivariable models to assess associations with partner change. Overall 7 % of women (n = 123) reported a new partner and 41 % (51) of those reported a new husband. Median gel adherence was reported to be 100 % in women with ongoing partners and 75 % for women with new partners (p < 0.001). In women reporting no gel use in their last sex act, only 12.5 % of the women with a new partner and none of those with an ongoing partner reported using condoms (p < 0.001). Fewer women with new partners reported using both the gel and condom during the last sex act as compared to women with ongoing partners (median 50 vs. 71.4 %, p < 0.001). After adjusting for age, site, education level, and sexual frequency, women with ongoing partners were more likely to report high gel adherence than those with new partners (AOR 2.5, 95 % CI 1.6, 3.9). This pattern persisted when gel use over time was compared between women with new versus ongoing partners. In the HPTN 035 trial, women with new partners had higher HIV incidence and reported less gel use and higher condom use. Specific counseling and support are needed to help women use potential HIV prevention methods, including microbicides, when they are changing partners.
| S-EPMC3988261 | biostudies-literature
Project description: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.
| S-EPMC5069326 | biostudies-literature
Project description: Not available
| S-EPMC1489187 | biostudies-literature