Using a medication event monitoring system to evaluate self-report and pill count for determining treatment completion with self-administered, once-weekly isoniazid and rifapentine.

BACKGROUND: Treatment completion is essential for the effectiveness of any latent tuberculosis infection (LTBI) regimen. The Tuberculosis Trials Consortium (TBTC) Study 33 (iAdhere) combined self-report and pill counts - standard of care (SOC) with a medication event monitoring system (MEMS) to determine treatment completion for 12-dose once-weekly isoniazid and rifapentine (3HP). Understanding the performance of SOC relative to MEMS can inform providers and suggest when interventions may be applied to optimize LTBI treatment completion. METHOD: iAdhere randomized participants to directly observed therapy (DOT), SAT, or SAT with text reminders in Hong Kong, South Africa, Spain and the United States (U.S.). This post-hoc secondary analysis evaluated treatment completion in both SAT arms, and compared completion based on SOC with MEMS to completion based on SOC only. Treatment completion proportions were compared. Characteristics associated with discordance between SOC and SOC with MEMS were identified. RESULTS: Overall 80.8% of 665 participants completed treatment per SOC, compared to 74.7% per SOC with MEMS, a difference of 6.1% (95%CI: 4.2%, 7.8%). Among U.S. participants only, this difference was 3.3% (95% CI: 1.8%, 4.9%). Differences in completion was 3.1% (95% CI: -1.1%, 7.3%) in Spain, and 36.8% (95% CI: 24.3%, 49.4%) in South Africa. There was no difference in Hong Kong. CONCLUSION: When used for monitoring 3HP, SOC significantly overestimated treatment completion in U.S. and South Africa. However, SOC still provides a reasonable estimate of treatment completion of the 3HP regimen, in U.S., Spain, and Hong Kong.

Nonparticipation reasons in a randomized international trial of a new latent tuberculosis infection regimen.

BACKGROUND/AIMS: Efficient recruitment of eligible participants, optimizing time and sample size, is a crucial component in conducting a successful clinical trial. Inefficient participant recruitment can impede study progress, consume staff time and resources, and limit quality and generalizability or the power to assess outcomes. Recruitment for disease prevention trials poses additional challenges because patients are asymptomatic. We evaluated candidates for a disease prevention trial to determine reasons for nonparticipation and to identify factors that can be addressed to improve recruitment efficiency. METHODS: During 2001-2009, the Tuberculosis Trials Consortium conducted Study 26 (PREVENT TB), a randomized clinical trial at 26 sites in four countries, among persons with latent tuberculosis infection at high risk for tuberculosis disease progression, comparing 3 months of directly observed once-weekly rifapentine plus isoniazid with 9 months of self-administered daily isoniazid. During March 2005-February 2008, non-identifying demographic information, risk factors for experiencing active tuberculosis disease, and reasons for not enrolling were collected from screened patients to facilitate interpretation of trial data, to meet Consolidated Standards of Reporting Trials standards, and to evaluate reasons for nonparticipation. RESULTS: Of the 7452 candidates screened in Brazil, Canada, Spain, and the United States, 3584 (48%) were not enrolled, because of ineligibility (41%), site decision (10%), or patient choice (49%). Among those who did not enroll by own choice, and for whom responses were recorded on whether they would accept treatment outside of the study (n = 1430), 68% reported that they planned to accept non-study latent tuberculosis infection treatment. Among 1305 patients with one or more reported reasons for nonparticipation, study staff recorded a total of 1886 individual reasons (reason count: median = 1/patient; range = 1-9) for why patients chose not to enroll, including grouped concerns about research (24% of 1886), work or school conflicts (20%), medication or health beliefs (16%), latent tuberculosis infection beliefs (11%), and patient lifestyle and family concerns (10%). CONCLUSION: Educational efforts addressing clinical research concerns and beliefs about medication and health, as well as study protocols that accommodate patient-related concerns (e.g. work, school, and lifestyle) might increase willingness to enter clinical trials. Findings from this evaluation can support development of communication and education materials for clinical trial sites at the beginning of a trial to allow study staff to address potential participant concerns during study screening.

Self-administered Versus Directly Observed Once-Weekly Isoniazid and Rifapentine Treatment of Latent Tuberculosis Infection: A Randomized Trial.

Background: Expanding latent tuberculosis treatment is important to decrease active disease globally. Once-weekly isoniazid and rifapentine for 12 doses is effective but limited by requiring direct observation. Objective: To compare treatment completion and safety of once-weekly isoniazid and rifapentine by self-administration versus direct observation. Design: An open-label, phase 4 randomized clinical trial designed as a noninferiority study with a 15% margin. Seventy-five percent or more of study patients were enrolled from the United States for a prespecified subgroup analysis. (ClinicalTrials.gov: NCT01582711). Setting: Outpatient tuberculosis clinics in the United States, Spain, Hong Kong, and South Africa. Participants: 1002 adults (aged ≥18 years) recommended for treatment of latent tuberculosis infection. Intervention: Participants received once-weekly isoniazid and rifapentine by direct observation, self-administration with monthly monitoring, or self-administration with weekly text message reminders and monthly monitoring. Measurements: The primary outcome was treatment completion, defined as 11 or more doses within 16 weeks and measured using clinical documentation and pill counts for direct observation, and self-reports, pill counts, and medication event-monitoring devices for self-administration. The main secondary outcome was adverse events. Results: Median age was 36 years, 48% of participants were women, and 77% were enrolled at the U.S. sites. Treatment completion was 87.2% (95% CI, 83.1% to 90.5%) in the direct-observation group, 74.0% (CI, 68.9% to 78.6%) in the self-administration group, and 76.4% (CI, 71.3% to 80.8%) in the self-administration-with-reminders group. In the United States, treatment completion was 85.4% (CI, 80.4% to 89.4%), 77.9% (CI, 72.7% to 82.6%), and 76.7% (CI, 70.9% to 81.7%), respectively. Self-administered therapy without reminders was noninferior to direct observation in the United States; no other comparisons met noninferiority criteria. A few drug-related adverse events occurred and were similar across groups. Limitation: Persons with latent tuberculosis infection enrolled in South Africa would not routinely be treated programmatically. Conclusion: These results support using self-administered, once-weekly isoniazid and rifapentine to treat latent tuberculosis infection in the United States, and such treatment could be considered in similar settings when direct observation is not feasible. Primary Funding Source: Centers for Disease Control and Prevention.