Effect of self-efficacy among persons who inject drugs treated with direct-acting antivirals on Hepatitis C treatment initiation, duration, completion, adherence, and cure.

BACKGROUND: Self-efficacy, a patient-level factor, has been shown to facilitate patient engagement in treatment and optimize treatment-related outcomes in various health contexts. Research on interventions supporting hepatitis C virus (HCV) direct-acting antiviral (DAA) treatment uptake and adherence among persons who inject drugs (PWID) is needed, but whether self-efficacy factors influence DAA treatment cascade outcomes in this population has been less studied. METHODS: Using the HERO study data, we analyzed a subset of participants with any general health self-efficacy data (n=708) measured at baseline and end-of-treatment time points using a 5-items instrument (facets: 'goal setting', 'goal attainment', 'having a positive effect', 'being in control', and 'working to improve'). The cascade outcomes included DAA treatment initiation, duration, adherence, completion, and sustained virologic response (SVR). The effect of baseline and change (Δ) scores for composite and item-level self-efficacy on the cascade outcomes was assessed using logistic regression and generalized linear models. RESULTS: Higher baseline composite self-efficacy [adjusted odds ratio (95 % confidence interval) =1.57 (1.07, 2.29)], 'goal attainment' [1.31 (1.03, 1.67)] and 'having a positive effect' [1.33 (1.03, 1.74)] were associated with greater likelihood of treatment initiation. 'Δ Goal attainment' was significantly associated with SVR [1.63 (1.04, 2.53)]. 'Δ Being in control' and 'Δ working to improve' were associated with treatment adherence and duration, respectively. CONCLUSIONS: General health self-efficacy positively influences DAA treatment initiation among PWID. 'Goal attainment' facilitates the achievement of DAA treatment-related outcomes. Further studies should assess the effect of self-efficacy related to performing healthcare tasks specific to DAAs on the treatment-related outcomes.

What does the scale-up of long-acting HIV pre-exposure prophylaxis mean for the global hepatitis B epidemic?

INTRODUCTION: The HIV and hepatitis B virus (HBV) epidemics are interconnected with shared routes of transmission and specific antiviral drugs that are effective against both viruses. Nearly, 300 million people around the world live with chronic HBV, many of whom are from priority populations who could benefit from HIV prevention services. Oral pre-exposure prophylaxis (PrEP) for HIV has implications in the prevention and treatment of HBV infection, but many people at increased risk of HIV acquisition may instead prefer long-acting formulations of PrEP, which are currently not active against HBV. DISCUSSION: People at increased risk for HIV acquisition may also be at risk for or already be living with HBV infection. Oral PrEP with tenofovir is effective in preventing both HIV and HBV, and tenofovir is also the recommended treatment for chronic HBV infection. Although implementation of oral PrEP has been challenging in sub-Saharan Africa, investments in its scale-up could secondarily reduce the clinical impact of HBV. Long-acting PrEP, including injectable medicines and implantable rings, may overcome some of the implementation challenges associated with oral PrEP, such as daily pill burden, adherence challenges and stigma; however, current formulations of long-acting PrEP do not have activity against HBV replication. Ideally, PrEP programmes would offer both oral and long-acting formulations with HBV screening to optimize HIV prevention services and HBV prevention and care, when appropriate. People who are not immune to HBV would benefit from being vaccinated against HBV before initiating long-acting PrEP. People who remain non-immune to HBV despite vaccination may benefit from being offered oral, tenofovir-based PrEP given its potential for HBV PrEP. People using PrEP and living with HBV who are not linked to dedicated HBV care would also benefit from laboratory monitoring at PrEP sites to ensure safety when using and after stopping tenofovir. PrEP programmes are ideal venues to offer HBV screening, HBV vaccination for people who are non-immune and treatment with tenofovir-based PrEP for people with indications for HBV therapy. CONCLUSIONS: Long-acting PrEP holds promise for reducing HIV incidence, but its implications for the HBV epidemic, particularly in sub-Saharan Africa, should not be overlooked.

Overreporting of adherence to hepatitis C direct-acting antiviral therapy and sustained virologic response among people who inject drugs in the HERO study.

BACKGROUND: Self-reported adherence to direct-acting antivirals (DAAs) to treat hepatitis C virus (HCV) among persons who inject drugs (PWID) is often an overreport of objectively measured adherence. The association of such overreporting with sustained virologic response (SVR) is understudied. This study among PWID aimed to determine a threshold of overreporting adherence that optimally predicts lower SVR rates, and to explore correlates of the optimal overreporting threshold. METHODS: This study analyzed per-protocol data of participants with adherence data (N = 493) from the HERO (Hepatitis C Real Options) study. Self-reported and objective adherence to a 12-week DAA regimen were measured using visual analogue scales and electronic blister packs, respectively. The difference (Δ) between self-reported and objectively measured adherence was calculated. We used the Youden index based on receiver operating characteristic (ROC) curve analysis to identify an optimal threshold of overreporting for predicting lower SVR rates. Factors associated with the optimal threshold of overreporting were identified by comparing baseline characteristics between participants at/above versus those below the threshold. RESULTS: The self-reported, objective, and Δ adherence averages were 95.1% (SD = 8.9), 75.9% (SD = 16.3), and 19.2% (SD = 15.2), respectively. The ≥ 25% overreporting threshold was determined to be optimal. The SVR rate was lower for ≥ 25% vs. < 25% overreporting (86.7% vs. 95.8%, p <.001). The factors associated with ≥ 25% Δ adherence were unemployment; higher number of days and times/day of injecting drugs; higher proportion of positive urine drug screening for amphetamine, methamphetamine, and oxycodone, and negative urine screening for THC (tetrahydrocannabinol)/cannabis. CONCLUSIONS: Self-reported DAA adherence was significantly greater than objectively measured adherence among PWID by 19.2%. Having ≥ 25% overreported adherence was associated with optimal prediction of lower SVR rates. PWID with risk factors for high overreporting may need to be more intensively managed to promote actual adherence.

Optimal hepatitis C treatment adherence patterns and sustained virologic response among people who inject drugs: The HERO study.

BACKGROUND & AIMS: Direct-acting antivirals (DAAs) are highly effective for treating HCV infection even among people who inject drugs (PWID). Yet, little is known about patients' adherence patterns and their association with sustained virologic response (SVR) rates. We aimed to summarize various adherence patterns and determine their associations with SVR. METHODS: Electronic blister packs were used to measure daily adherence to once-a-day sofosbuvir/velpatasvir during the 12-week treatment period among active PWIDs. Blister pack data were available for 496 participants who initiated DAAs for whom SVR status was known. Adherence was summarized in multiple patterns, such as total adherent days, consecutive missed days, and early discontinuations. Thresholds for adherence patterns associated with >90% SVR rates were also determined. RESULTS: The overall SVR rate was 92.7%, with a median adherence rate of 75%. All adherence patterns indicating greater adherence were significantly associated with achieving SVR. Participant groups with ≥50% (>42/84) adherent days or <26 consecutive missed days achieved an SVR rate of >90%. Greater total adherent days during 9-12 weeks and no early discontinuation were significantly associated with higher SVR rates only in those with <50% adherence. Participants with first month discontinuation and ≥2 weeks of treatment interruption had low SVR rates, 25% and 85%, respectively. However, greater adherent days were significantly associated with SVR (adjusted odds ratio 1.10; 95% CI 1.04-1.16; p <0.001) even among participants with ≥14 consecutive missed days. CONCLUSIONS: High SVR rates can be achieved in the PWID population despite suboptimal adherence. Encouraging patients to take as much medication as possible, with <2 weeks consecutive missed days and without early discontinuation, was found to be important for achieving SVR. IMPACT AND IMPLICATIONS: People who inject drugs can be cured of HCV in >90% of cases, even with relatively low adherence to direct-acting antivirals, but early discontinuations and long treatment interruptions can significantly reduce the likelihood of achieving cure. Clinicians should encourage people who inject drugs who are living with HCV to adhere daily to direct-acting antivirals as consistently as possible, but if any days are interrupted, to continue and complete treatment. These results from the HERO study are important for patients living with HCV, clinicians, experts writing clinical guidelines, and payers. CLINICAL TRIAL NUMBER: NCT02824640.

Virological, serological and clinical outcomes in chronic hepatitis B virus infection: development and validation of the HEPA-B simulation model.

OBJECTIVES: Detailed simulation models are needed to assess strategies for prevention and treatment of hepatitis B virus (HBV) infection, the world's leading cause of liver disease. We sought to develop and validate a simulation model of chronic HBV that incorporates virological, serological and clinical outcomes. METHODS: We developed a novel Monte Carlo simulation model (the HEPA-B Model) detailing the natural history of chronic HBV. We parameterised the model with epidemiological data from the Western Pacific and sub-Saharan Africa. We simulated the evolution of HBV DNA, 'e' antigen (HBeAg) and surface antigen (HBsAg). We projected incidence of HBeAg loss, HBsAg loss, cirrhosis, hepatocellular carcinoma (HCC) and death over 10-year and lifetime horizons. We stratified outcomes by five HBV DNA categories at the time of HBeAg loss, ranging from HBV DNA<300 copies/mL to >106 copies/mL. We tested goodness of fit using intraclass coefficients (ICC). RESULTS: Model-projected incidence of HBeAg loss was 5.18% per year over lifetime (ICC, 0.969 (95% CI: 0.728 to 0.990)). For people in HBeAg-negative phases of infection, model-projected HBsAg loss ranged from 0.78% to 3.34% per year depending on HBV DNA level (ICC, 0.889 (95% CI: 0.542 to 0.959)). Model-projected incidence of cirrhosis was 0.29-2.09% per year (ICC, 0.965 (95% CI: 0.942 to 0.979)) and HCC incidence was 0.06-1.65% per year (ICC, 0.977 (95% CI: 0.962 to 0.986)). Over a lifetime simulation of HBV disease, mortality rates were higher for people with older age, higher HBV DNA level and liver-related complications, consistent with observational studies. CONCLUSIONS: We simulated HBV DNA-stratified clinical outcomes with the novel HEPA-B Model and validated them to observational data. This model can be used to examine strategies of HBV prevention and management.

Self-reported and measured adherence to hepatitis C direct-acting antiviral therapy and sustained virologic response among people who inject drugs: The HERO study.

BACKGROUND: Objective adherence measures, such as electronic blister pack (BP), for direct-acting antivirals (DAAs) for hepatitis C virus (HCV) treatment have high accuracy, but their use is limited in real practice settings. We examined the association of self-reported adherence using a visual analogue scale (VAS) with objective BP adherence and sustained virologic response (SVR) among people who inject drugs. METHODS: We conducted secondary analyses using a subset of participants (N = 493) from the per-protocol sample of the HERO study, a pragmatic randomized trial of HCV treatment interventions that used both VAS and BP to measure adherence to a 12-week sofosbuvir/velpatasvir DAA regimen. Multivariable mixed-effects regression models tested the association of self-report adherence level with longitudinal weekly objective adherence. Multivariable logistic regression tested the association of self-report adherence with SVR. RESULTS: The average VAS and BP adherences were 95.1 % (SD = 8.9 %) and 76.0 % (16.0 %), respectively, and the proportion of the participants achieving SVR was 92.9 %. The estimated adjusted mean objective adherence was significantly different (-16 %; 95 % CI: -22 %, -11 %, p < .001) between participants with 100 % and <80 % VAS adherence. The likelihood of SVR was significantly lower for those with <80 % VAS adherence [adjusted OR = 0.07; 95 % CI: 0.02, 0.24; p < .001] compared to those with 100 %. CONCLUSION: Self-reported adherence overestimated objective adherence. However, higher self-report adherence was significantly associated with higher objective adherence. Also, self-reported adherence ≥80 % was significantly associated with SVR. Thus, the self-report measure has utility as a monitoring tool for adherence during DAA treatment.