Exploring COVID-19 vaccine uptake and hesitancy among vulnerable populations in inner city Vancouver, Canada: Insights into characteristics and clinical outcomes

The COVID-19 pandemic is having a profound impact on the health, social and economic well-being of people in Canada and around the world. To address vaccine disparity among vulnerable populations facing social-structural challenges, it is crucial to provide evidence-based information on the importance of completion of the recommended vaccination schedule. In this study, we investigated vaccination rates and variables as facilitators or barriers to COVID-19 vaccination among vulnerable populations living in Vancouver's inner-city residents. On a weekly basis, a team (including health care providers [HCPs] and support staff) conducts a Community Pop-up Clinic (CPC) event at single room occupancy dwellings in Vancouver's inner city to provide COVID-19 vaccine and/or related information. Participants also completed a survey about their COVID-19 vaccination status and COVID knowledge, including knowledge about COVID vaccination. We collected data from 892 CPC participants between January 2021-August 2023. The median age at baseline was 45 (IQR 36-55) years, with 317 (35.5 %) female and 285 (31.9 %) self-identified as Indigenous. Within the population, 512 (57.4 %) reported unstable housing and 441 (49.5 %) were active injection drug users. Regarding COVID-19 vaccinations, 235 (26.3 %) were unvaccinated, 119 (13.3 %) had received one dose of the COVID-19 vaccine, 432 (48.4 %) had received 2 doses, and 106 (11.8 %) had received at least 3 doses. Variables such as age (AOR 2.28, 95 % CI 1.37-3.80, p < 0.001) and HCV seropositivity (AOR 1.91, 95 % CI 1.20-3.04, p = 0.005) were significantly associated with higher odds of vaccination uptake. Conversely, unstable housing was significantly associated with a lower odds of vaccination uptake (AOR 0.53, 95 % CI 0.35-0.79, p = 0.002). Results from this study suggest that targeted community focused initiatives are crucial to address vaccine disparity among vulnerable populations living in Vancouver's inner city facing unstable housing and drug use injection.

GRAND PLAN: Safety and Efficacy of Glecaprevir/Pibrentasvir for the Treatment of Hepatitis C Virus Infection Among People Initially Disengaged From Health Care Who Use Drugs-A Systematic Multidisciplinary Approach

Background

GRAND PLAN is a prospective, open-label, phase 4 study. Based at a single center and with a single arm, GRAND PLAN evaluated the safety and efficacy of an 8-week course of glecaprevir/pibrentasvir (G/P) among active drug users with hepatitis C virus (HCV) infection in a population enriched for factors that may reduce treatment uptake and success, such as disengagement from health care and unstable housing.

Methods

Participants were ≥19 years old and actively using drugs and were confirmed viremic, noncirrhotic, and HCV treatment naive. All participants provided informed consent before any study procedures. They received G/P for 8 weeks within a multidisciplinary model of care, with daily, weekly, or monthly dispensing of medications to optimize adherence.

Results

We identified 117 eligible patients with a median age of 46 years (range, 22-75): 27% were female, 21.4% were Indigenous, 48.7% were unstably housed, and 95.7% were active drug users (94.9% fentanyl). One patient did not start treatment, and 4 underwent <1 week of treatment, leaving 112 completed treatments with 94.6% picking up medications weekly. HCV RNA was undetectable at the end of treatment in all 112 patients. One died of unknown causes shortly after treatment. A cure was demonstrated in 108 of 111 (97.3%) cases at the SVR12 time point (sustained virologic response at ≥12 weeks); the other 3 experienced virologic relapse. Considering the entire cohort, the intent-to-treat success rate was 92.3% (108/117). HCV reinfection was documented at SVR24 in 5 cases, 2 of which were successfully retreated.

Conclusions

GRAND PLAN demonstrates that administration of an 8-week course of G/P to inner-city residents with HCV infection leads to a cure >95%. With a short course of treatment, G/P is an attractive option for this population in helping us achieve the World Health Organization's HCV objectives by 2030.

Baseline characteristics of a prospective cohort study of aging and cardiovascular diseases among people living with HIV

OBJECTIVES

Our objective was to report the baseline characteristics of participants in the Canadian HIV and Aging Cohort Study (CHACS) and present amendments to the initial protocol.

METHODS

CHACS is a multi-centred prospective cohort study that was initially set from 2011 to 2016 and will now continue recruitment until 2024. Four additional years of follow-up have been added, and additional outcomes and covariates will be prospectively collected. Frailty will be assessed using a modified version of the Fried's frailty phenotype. The four interrelated aspects of gender-gender roles, gender identity, gender relationships, and institutionalized gender-will be measured using the GENESIS-PRAXY questionnaire. Diet will be assessed using a validated, web-based, self-administered food frequency questionnaire.

RESULTS

A total of 1049 participants (77% people living with HIV) were recruited between September 2011 and September 2019. Median age at baseline was 54 years (interquartile range 50-61). Most participants were male (84%) and white (83%). Compared with participants without HIV, those with HIV were more likely to be male; to report lower education levels and incomes; to be more sedentary; to use tobacco, recreational, and prescription drugs; to report a personal history of cardiovascular diseases; and to be frail.

CONCLUSIONS

The new assessments added to the CHACS protocol will allow for an even more detailed portrait of the pathways leading to accentuated aging for people living with HIV. Participants in the CHACS cohort display important differences in socio-economic and cardiovascular risk factors according to HIV serostatus. These imbalances must be taken into account for all further inferential analyses.

Determining reinfection rates by hepatitis C testing interval among key populations: A systematic review and meta-analysis

BACKGROUND & AIMS

Detecting hepatitis C virus (HCV) reinfection among key populations helps prevent ongoing transmission. This systematic review aims to determine the association between different testing intervals during post-SVR follow-up on the detection of HCV reinfection among highest risk populations.

METHODS

We searched electronic databases between January 2014 and February 2023 for studies that tested individuals at risk for HCV reinfection at discrete testing intervals and reported HCV reinfection incidence among key populations. Pooled estimates of reinfection incidence were calculated by population and testing frequency using random-effects meta-analysis.

RESULTS

Forty-one single-armed observational studies (9453 individuals) were included. Thirty-eight studies (8931 individuals) reported HCV reinfection incidence rate and were included in meta-analyses. The overall pooled estimate of HCV reinfection incidence rate was 4.13 per 100 per person-years (py) (95% confidence interval [CI]: 3.45-4.81). The pooled incidence estimate among people who inject drugs (PWID) was 2.84 per 100 py (95% CI: 2.19-3.50), among men who have sex with men (MSM) 7.37 per 100 py (95% CI: 5.09-9.65) and among people in custodial settings 7.23 per 100 py (95% CI: 2.13-16.59). The pooled incidence estimate for studies reporting a testing interval of ≤6 months (4.26 per 100 py; 95% CI: 2.86-5.65) was higher than studies reporting testing intervals >6 months (5.19 per 100 py; 95% CI: 3.92-6.46).

CONCLUSIONS

HCV reinfection incidence was highest in studies of MSM and did not appear to change with retesting interval. Shorter testing intervals are likely to identify more reinfections, help prevent onward transmission where treatment is available and enable progress towards global HCV elimination, but additional comparative studies are required.

Real-world Evidence for Impact of Opioid Agonist Therapy on Nonfatal Overdose in Patients with Opioid Use Disorder during the COVID-19 Pandemic

OBJECTIVES

The primary objectives of this study were to describe the demographics and clinical characteristics of patients who were treated with buprenorphine extended-release versus buprenorphine-naloxone sublingual tablets versus methadone in a real-world setting and to evaluate the difference in nonfatal overdose events between treatment cohorts.

METHODS

This study was a retrospective chart review of patients with opioid use disorder initiating opioid agonist therapy in Canada during the outset of the COVID-19 pandemic (March 11, 2020 to October 31, 2021). Three treatment cohorts were defined by the initial prescribed opioid agonist therapy regimen: buprenorphine extended-release, buprenorphine-naloxone sublingual tablets, and methadone. Baseline characteristics, as well as treatment status, overdose events, and substance use 6 months after treatment initiation were collected using a standardized form.

RESULTS

Nine clinics provided data on 379 patient cases. The incidence rate (number of events per 100 person-years) for a self-reported nonfatal overdose was 46.8 (n = 18), 19.3 (n = 10), and 1.7 (n = 1) in the methadone, buprenorphine-naloxone sublingual tablets, and buprenorphine extended-release cohorts, respectively. The risk-adjusted difference for the proportion of patients with nonfatal overdose was 8.59% (95% confidence interval, 3.10-14.08%; P = 0.0022) for methadone versus buprenorphine extended-release and 6.51% (95% confidence interval, 1.46-11.56%; P = 0.0115) for buprenorphine-naloxone sublingual tablets versus buprenorphine extended-release.

CONCLUSIONS

Buprenorphine extended-release was associated with lower rates of nonfatal overdose events compared with daily opioid agonist therapy. Given the limitations of this naturalistic, retrospective design, further prospective studies are needed to validate these findings and demonstrate the potential for long-acting opioid agonist therapy in addressing the opioid crisis.

Reported adverse events related to use of hepatitis C virus direct-acting antivirals with opioids: 2017-2021

INTRODUCTION

Due to concerns over potential interactions between some hepatitis C direct-acting antivirals (DAAs) and opioids, we describe adverse event (AE) reports of concomitant use of opioids and DAAs.

METHODS

AEs reported (July 28, 2017-December 31, 2021) with the administration of the DAAs glecaprevir/pibrentasvir, sofosbuvir/velpatasvir, ledipasvir/sofosbuvir, sofosbuvir/velpatasvir/voxilaprevir, and elbasvir/grazoprevir as suspect products were downloaded from the US Food and Drug Administration AE Reporting System Public Dashboard. The number of AE reports containing opioids (fentanyl, hydrocodone, oxycodone) as co-suspect products/concomitant products were counted and summarized by severity, reporting country and whether an outcome of death was reported. Overdose AEs were counted irrespective of opioid use, and changes over time were assessed.

RESULTS

In total, 40 AEs were reported for DAAs and concomitant fentanyl use, 25 (62.5%) were in the USA, 35 (87.5%) were considered serious, and 14 (35.0%) resulted in death; and 626 were reported with concomitant oxycodone/hydrocodone use, 596 (95.2%) were in the USA, 296 (47.3%) were considered serious, and 28 (4.5%) resulted in death. There were 196 overdose AEs (32 [16%] deaths) declining from 2018 (N = 56) to 2021 (N = 29).

CONCLUSIONS

Treating people with hepatitis C virus (HCV) infection who use drugs is key to achieving HCV elimination. Low numbers of DAA AE reports with opioids may provide reassurance to prioritize HCV treatment in this population. These data contribute to evidence supporting the continued scale-up of DAA treatment among people who use drugs to achieve HCV elimination goals.

Assessment of Drug-Drug Interaction Risk Between Intravenous Fentanyl and the Glecaprevir/Pibrentasvir Combination Regimen in Hepatitis C Patients Using Physiologically Based Pharmacokinetic Modeling and Simulations

INTRODUCTION

An unsafe injection practice is one of the major contributors to new hepatitis C virus (HCV) infections; thus, people who inject drugs are a key population to prioritize to achieve HCV elimination. The introduction of highly effective and well-tolerated pangenotypic direct-acting antivirals, including glecaprevir/pibrentasvir (GLE/PIB), has revolutionized the HCV treatment landscape. Glecaprevir is a weak cytochrome P450 3A4 (CYP3A4) inhibitor, so there is the potential for drug-drug interactions (DDIs) with some opioids metabolized by CYP3A4, such as fentanyl. This study estimated the impact of GLE/PIB on the pharmacokinetics of intravenous fentanyl by building a physiologically based pharmacokinetic (PBPK) model.

METHODS

A PBPK model was developed for intravenous fentanyl by incorporating published information on fentanyl metabolism, distribution, and elimination in healthy individuals. Three clinical DDI studies were used to verify DDIs within the fentanyl PBPK model. This model was integrated with a previously developed GLE/PIB PBPK model. After model validation, DDI simulations were conducted by coadministering GLE 300 mg + PIB 120 mg with a single dose of intravenous fentanyl (0.5 µg/kg).

RESULTS

The predicted maximum plasma concentration ratio between GLE/PIB + fentanyl and fentanyl alone was 1.00, and the predicted area under the curve ratio was 1.04, suggesting an increase of only 4% in fentanyl exposure.

CONCLUSION

The administration of a therapeutic dose of GLE/PIB has very little effect on the pharmacokinetics of intravenous fentanyl. This negligible increase would not be expected to increase the risk of fentanyl overdose beyond the inherent risks related to the amount and purity of the fentanyl received during recreational use.

Patient-Reported Outcomes During and After Hepatitis C Virus Direct-Acting Antiviral Treatment Among People Who Inject Drugs

OBJECTIVES

People who inject drugs (PWID) are at a high risk of hepatitis C virus (HCV) infection. HCV cure is associated with improved patient-reported outcomes (PROs), but there are little data among PWID. This study aimed to assess the change in PROs during and after HCV direct-acting antiviral (DAA) treatment.

METHODS

This analysis used data from 2 clinical trials of DAA treatment in PWID. PROs assessed included health-related quality of life, social functioning, psychological distress, housing, and employment. Generalized estimating equations and group-based trajectory modeling were used to assess changes in PROs over time.

RESULTS

No significant changes in the 3-level version of EQ-5D scores, EQ visual analogue scale scores, social functioning, psychological distress, and housing were observed over the 108-week study period. There was a significant increase in the proportion of participants employed (18% [95% confidence interval (CI) 12%-23%] at baseline to 28% [95% CI 19%-36%] at the end of the study). Participants were more likely to be employed at 24 weeks and 108 weeks after commencing treatment. Having stable housing increased the odds of being employed (odds ratio 1.70; 95% CI 1.00-2.90). The group-based trajectory modeling demonstrated that most outcomes remained stable during and after DAA treatment.

CONCLUSIONS

Although no significant improvement was identified in health-related quality of life after HCV DAA treatment, there was a modest but significant increase in employment during study follow-up. The study findings support the need for multifaceted models of HCV care for PWID addressing a range of issues beyond HCV treatment to improve quality of life.

Pinless Electromagnetic Neuronavigation During Awake Craniotomies: Technical Pearls, Pitfalls, and Nuances

BACKGROUND

Awake craniotomies are often performed with rigid pin fixation and optical neuronavigation. Newer electromagnetic (EM) neuronavigation technology now enables un-pinned cranial neurosurgery while maintaining robust intraoperative image guidance. Here we share technical nuances, operative pearls, and lessons learned from our institutional experience using Curve® EM (Brainlab, Inc.) neuronavigation during awake, unpinned craniotomies.

METHODS

Here we describe our process for patient positioning, instrumentation set-up, system registration, intraoperative navigation, and surgical adjunct use (e.g., intraoperative neuro monitoring and iMRI) in detail. At each step, we provide pearls for success and tips for pitfall avoidance based on our experience.

RESULTS

Ten patients underwent pinless intra-axial tumor resection using Curve® EM neuronavigation from May 2021 to August 2022 with a single surgeon. Post-operative transient neurological deficits were seen in 80.0% (8/10) of cases, as all resections were taken to functional margins. Of the cases with a 3-month follow up at the time of publication (9/10), 100% (9/9) saw improved or stable pre-operative symptoms. Importantly, there were no surgical complications, clinically appreciable inaccuracies, intraoperative losses of registration, unexpected postoperative MRI findings, or errors related to the use of EM neuronavigation.

CONCLUSION

The technical pearls outlined here will help ensure EM neuronavigation's safe integration into awake craniotomies for interested parties. In our experience, unpinned neuronavigation provides many advantages to the patient, surgeon, and entire operative team, and it has thus become the standard practice for awake cases at our institution.

Reinfection and Risk Behaviors After Treatment of Hepatitis C Virus Infection in Persons Receiving Opioid Agonist Therapy : A Cohort Study

BACKGROUND

Hepatitis C virus (HCV) reinfection after successful treatment may reduce the benefits of cure among people who inject drugs.

OBJECTIVE

To evaluate the rate of HCV reinfection for 3 years after successful treatment among people receiving opioid agonist therapy (OAT).

DESIGN

A 3-year, long-term, extension study of persons enrolled in the CO-STAR (Hepatitis C Patients on Opioid Substitution Therapy Antiviral Response) study (ClinicalTrials.gov: NCT02105688).

SETTING

55 clinical trial sites in 13 countries.

PATIENTS

Aged 18 years and older with chronic HCV infection with genotypes 1, 4, or 6 receiving stable OAT.

INTERVENTION

No treatments were administered.

MEASUREMENTS

Serum samples were assessed for HCV reinfection. Urine drug screening was performed.

RESULTS

Among 296 participants who received treatment, 286 were evaluable for reinfection and 199 were enrolled in the long-term extension study. The rate of HCV reinfection was 1.7 [95% CI, 0.8 to 3.0] per 100 person-years; 604 person-years of follow-up). A higher rate of reinfection was seen among people with recent injecting drug use (1.9 [95% CI, 0.5 to 4.8] per 100 person-years; 212 person-years). Ongoing drug use and injecting drug use were reported by 59% and 21% of participants, respectively, at the 6-month follow-up visit and remained stable during 3 years of follow-up.

LIMITATIONS

Participants were required to be 80% adherent to OAT at baseline and may represent a population with higher stability and lower risk for HCV reinfection. Rate of reinfection may be underestimated because all participants did not continue in the long-term extension study; whether participants who discontinued were at higher risk for reinfection is unknown.

CONCLUSION

Reinfection with HCV was low but was highest in the first 24 weeks after treatment completion and among people with ongoing injecting drug use and needle-syringe sharing.

PRIMARY FUNDING SOURCE

Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.

Nationwide retrospective study of hepatitis B virological response and liver stiffness improvement in 465 patients on nucleos(t)ide analogue

BACKGROUND

Hepatitis B virus (HBV) nucleos(t)ide analog (NA) therapy reduces liver disease but requires prolonged therapy to achieve hepatitis B surface antigen (HBsAg) loss. There is limited North American real-world data using non-invasive tools for fibrosis assessment and few have compared 1^st generation NA or lamivudine (LAM) to tenofovir disoproxil fumarate (TDF).

AIM

To assess impact of NA on virological response and fibrosis regression using liver stiffness measurement (LSM) (i.e., FibroScan^®).

METHODS

Retrospective, observational cohort study from the Canadian HBV Network. Data collected included demographics, NA, HBV DNA, alanine aminotransferase (ALT), and LSM. Patients were HBV monoinfected patients, treatment naïve, and received 1 NA with minimum 1 year follow-up.

RESULTS

In 465 (median 49 years, 37% female, 35% hepatitis B e antigen⁺ at baseline, 84% Asian, 6% White, and 9% Black). Percentage of 64 (n = 299) received TDF and 166 were LAM-treated with similar median duration of 3.9 and 3.7 years, respectively. The mean baseline LSM was 11.2 kPa (TDF) vs 8.3 kPa (LAM) (P = 0.003). At 5-year follow-up, the mean LSM was 7.0 kPa in TDF vs 6.7 kPa in LAM (P = 0.83). There was a significant difference in fibrosis regression between groups (i.e., mean -4.2 kPa change in TDF and -1.6 kPa in LAM, P < 0.05). The last available data on treatment showed that all had normal ALT, but more TDF patients were virologically suppressed (< 10 IU/mL) (n = 170/190, 89%) vs LAM-treated (n = 35/58, 60%) (P < 0.05). None cleared HBsAg.

CONCLUSION

In this real-world North American study, approximately 5 years of NA achieves liver fibrosis regression rarely leads to HBsAg loss.

Health-related quality of life in people receiving opioid agonist treatment and treatment for hepatitis C virus infection

BACKGROUND

In people with chronic hepatitis C virus (HCV) infection, viral eradication is associated with improved health-related quality of life (HRQOL).

OBJECTIVE

To assess changes in HRQOL among participants receiving opioid agonist therapy undergoing treatment for HCV infection.

METHODS

COSTAR (NCT02251990) was a randomized, double-blind, placebo-controlled study. Adults with HCV infection on opioid agonist therapy received elbasvir (50 mg)/grazoprevir (100 mg) or placebo for 12 weeks. HRQOL was evaluated using the Medical Outcomes Study 36-Item Short Form Health Survey version 2 (SF-36v2) Acute Form. Participants remained blinded until 4 weeks after end of treatment.

RESULTS

Overall, 201 participants received elbasvir/grazoprevir and 100 participants received placebo. Treatment difference mean change from baseline scores (elbasvir/grazoprevir minus placebo) indicated an improvement in HRQOL at 4 weeks after end of treatment in participants receiving elbasvir/grazoprevir versus those receiving placebo, driven by declining HRQOL in those receiving placebo and improved HRQOL in certain domains among participants receiving elbasvir/grazoprevir. Notable differences in SF-36v2 scores were evident in the general health (mean treatment difference [MTD], 6.00; 95% CI, 1.37-10.63), vitality (MTD, 6.81; 95% CI, 1.88-11.75), and mental health (MTD, 5.17; 95% CI, 0.52-9.82) domains and in the mental component summary score (mean, 2.83; 95% CI, 0.29-5.37). No notable between-treatment differences were evident at treatment weeks 4 or 12.

CONCLUSION

HRQOL in patients receiving medication for opioid dependence was improved following treatment for HCV infection with elbasvir/grazoprevir, suggesting that eradication of HCV infection with direct-acting antivirals is associated with improved HRQOL.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT02251990.

A randomized control trial of high-dose micronutrient-antioxidant supplementation in healthy persons with untreated HIV infection

Background

Although micronutrient and antioxidant supplementation are widely used by persons with human immunodeficiency virus (HIV), a therapeutic role beyond recommended daily allowances (RDA) remains unproven. An oral high-dose micronutrient and antioxidant supplement (Treatment) was compared to an RDA supplement (Control) for time to progressive immunodeficiency or initiation of antiretroviral therapy (ART) in people living with HIV (PLWH).

Methods

This study was a randomized, double-blind, placebo-controlled multicenter clinical trial. PLWH were recruited from Canadian HIV Trials Network sites, and followed quarterly for two years. Eligible participants were asymptomatic, antiretroviral treatment (ART)-naïve, HIV-seropositive adults with a CD4 T lymphocyte count (CD4 count) between 375–750 cells/μL. Participants were randomly allocated 1:1 to receive Treatment or Control supplements. The primary outcome was a composite of time-to-first of confirmed CD4 count below 350 cells/μL, initiation of ART, AIDS-defining illness or death. Primary analysis was by intention-to-treat. Secondary outcomes included CD4 count trajectory from baseline to ART initiation or two years. A Data and Safety Monitoring Board reviewed the study for safety, recruitment and protocol adherence every six months.

Results

Of 171 enrolled participants: 66 (38.6%) experienced a primary outcome: 27 reached a CD4 count below 350 cells/μL, and 57 started ART. There was no significant difference in time-to-first outcome between groups (Hazard Ratio = 1.05; 95%CI: 0.65, 1.70), or in time to any component outcome. Using intent-to-treat censoring, mean annualized rates of CD4 count decline were -42.703 cells/μL and -79.763 cells/μL for Treatment and Control groups, with no statistical difference in the mean change between groups (-37.06 cells/μL/52 weeks, 95%CI: (-93.59, 19.47); p = 0.1993). Accrual was stopped at 171 of the 212 intended participants after an interim analysis for futility, although participant follow-up was completed.

Conclusions

In ART-naïve PLWH, high-dose antioxidant, micronutrient supplementation compared to RDA supplementation had no significant effect on disease progression or ART initiation.

Clinical trial registration

ClinicalTrials.gov Identifier: NCT00798772.

Safety and Effectiveness Using 8 Weeks of Glecaprevir/Pibrentasvir in HCV-Infected Treatment-Naïve Patients with Compensated Cirrhosis: The CREST Study

Introduction

In clinical trials with hepatitis C virus-infected treatment-naïve (TN) patients with compensated cirrhosis (CC), glecaprevir/pibrentasvir (G/P), a fixed-dose, once-daily, pangenotypic regimen, has demonstrated sustained virologic response at posttreatment Week 12 (SVR12) > 95%. We evaluated the real-world safety and effectiveness of 8-week G/P therapy in TN patients with CC, including certain subgroups of interest.

Methods

The CREST study is a real-world, noninterventional, multicenter study retrospectively assessing data from Canada, Germany, Israel, Italy, and Spain. The full analysis set (FAS) designated all patients in the study; the modified analysis set (MAS) excluded patients who discontinued G/P for nonvirologic failure or who had missing SVR12 data. The primary endpoint was SVR12; safety endpoints were also assessed.

Results

A total of 386 patients were included in the FAS, 375 patients completed the study, and 325 patients were included in the MAS; 51 patients had missing SVR12 data. Overall, in the MAS and FAS, SVR12 was achieved in 99.1% and 84.2% of patients, respectively. In subgroups of interest, the percentage of patients achieving SVR12 in the MAS (and FAS) was: genotype (GT)3: 97.5% (80.6%); FibroScan^® ≥ 12.5 kPa: 98.9% (89.3%); platelet count < 100 × 10⁹/l: 100% (88.2%); both platelets < 150 × 10⁹/l and FibroScan^® > 20 kPa: 100% (88.9%); aspartate aminotransferase-to-platelet ratio index > 1.09: 98.7% (83.1%); fibrosis-4 index > 3.25: 98.6% (84.0%); albumin < 3 g/dl: 100% (91.7%); people who use drugs: 97.7% (84.3%); psychiatric disorders: 96.6% (84.8%); and human immunodeficiency virus coinfection: 100% (95.0%). Overall, 26.9% (104/386) of patients experienced an adverse event, none of which were classed as serious.

Conclusion

In this real-world cohort, 8 weeks of G/P therapy was well tolerated in TN patients with CC. SVR12 rates were similar to clinical trials, supporting 8-week treatment in TN patients with CC, including those with signs of advanced liver disease and GT3 infection.

Disclosure of HIV-serodiscordant relationships and association with viral suppression: results from the Positive Plus One study

BACKGROUND

Little is known about the effects of disclosure of HIV-serodiscordant relationships on clinical outcomes. We aimed to evaluate the effect of relationship disclosure on HIV viral suppression, and hypothesized that disclosure by HIV-positive and HIV-negative partners would be associated with viral suppression in the HIV-positive partner.

METHODS

We conducted a Canadian national online and telephone-administered survey of HIV-positive and HIV-negative partners in serodiscordant relationships. The primary outcome was self-reported viral suppression. Multivariable analyses were undertaken using Firth logistic regression.

RESULTS

We recruited 540 participants in current serodiscordant relationships (n = 228 HIV-negative; n = 312 HIV-positive). Similar proportions of HIV-positive and HIV-negative partners disclosed their relationship to healthcare professionals (82% v. 76%, p = 0.13). Among HIV-positive partners, disclosure of the relationship to healthcare professionals increased the odds of viral suppression (aOR = 4.7; CI: 2.13, 10.51) after adjusting for age, education, and relationship turmoil due to HIV. Increasing age (aOR = 1.28; 95% CI = 1.07, 1.55) and education (aOR = 2.43; 95% CI = 1.15, 5.26) were also associated with viral suppression. Among HIV-negative partners, relationship disclosure was not associated with viral suppression and HIV-negative heterosexual men were less likely to report that their HIV-positive partners were virally suppressed (aOR = 0.24; CI: 0.09, 0.61).

CONCLUSIONS

Disclosure of HIV-serodiscordant status by HIV-positive participants to healthcare professionals was associated with increased odds of viral suppression. Similar effects were not evident among HIV-negative participants. Future work should explore factors that empower relationship disclosure and incorporate them into supportive services for HIV-serodiscordant relationships.

Virological Outcomes After Switching to Abacavir/Lamivudine/Dolutegravir Combined with Adherence Support in People Living with HIV with Poor Adherence: A Phase IV, Multicentre Randomized Prospective Open Label Study (TriiADD-CTN 286)

BACKGROUND

Many people living with HIV struggle to consistently adhere to antiretroviral therapy, fail to achieve long-term virologic control and remain at risk for HIV-related disease progression, development of resistance and may transmit HIV infection to others.

OBJECTIVE

To determine if switching from current multi-tablet (curART) to single-tablet antiretroviral therapy (abacavir/lamivudine/dolutegravir; ABC/3TC/DTG), both combined with individualized adherence support, would improve HIV suppression in non-adherent vulnerable populations.

METHODS

TriiADD was an investigator-initiated randomized, multicentre, open label study. HIV+ adults with documented non-adherence on curART were randomized in a 1:1 ratio to immediately switch to ABC/3TC/DTG or to continue curART. Both arms received adherence support. The primary outcome was the proportion of participants in each arm with HIV RNA < 50 copies/mL 24 weeks after randomization.

RESULTS

In total, 50 people were screened and 27 randomized from 11 sites across Canada before the trial was stopped early due to slow recruitment. Participants were predominantly from ethnocultural communities, Indigenous people and/or had a history of injection drug use. The proportion achieving HIV RNA < 50 copies/mL at week 24 was 4/12 (33%) in the curART arm vs 7/13 (54%) in the ABC/3TC/DTG arm; median Bayesian risk difference, 5% (95% CrI, -17 to 28%) higher for those randomized to ABC/3TC/DTG. We encountered difficulties with recruitment of participants without prior drug resistance, retention despite intensive support, reliably measuring adherence and in overcoming entrenched adherence barriers.

CONCLUSION

Results of our trial are consistent with a slight improvement in viral suppression in a vulnerable population when a single tablet regimen is combined with patient-level adherence support. Beyond treatment simplicity and tolerability, tailored interventions addressing stigma and social determinants of health are still needed. The numerous challenges we encountered illustrate how randomised trials may not be the best approach for assessing adherence interventions in vulnerable populations.

Real-world evidence of sofosbuvir/velpatasvir as an effective and simple hepatitis C virus treatment and elimination tool in homeless populations

Background: People experiencing homelessness are disproportionately affected by hepatitis C virus (HCV) and can face specific barriers to care. Simple treatment algorithms could increase linkage to care in this population. Methods: This retrospective real-world analysis pooling data from 15 clinical cohorts evaluated effectiveness of a once-daily sofosbuvir/velpatasvir (SOF/VEL) regimen in HCV-infected people experiencing homelessness. The primary outcome was sustained virological response (SVR) in the effectiveness population (patients with confirmed SVR status). Secondary outcomes included reasons for not achieving SVR, adherence and time between diagnosis and SOF/VEL treatment start. Results: Of 153 patients treated with SOF/VEL for 12 weeks without ribavirin, SVR was 100% in the effectiveness population (n = 122), irrespective of various baseline factors including active injecting drug use and presence of mental health disorders. Conclusion: HCV-infected people experiencing homelessness can successfully be treated with SOF/VEL. SOF/VEL enables implementation of simple treatment algorithms and can support test-and-treat strategies through rapid treatment starts and minimal monitoring.

Characterizing risk behaviour and reinfection rates for successful programs to engage core transmitters in HCV elimination (C-RESPECT)

BACKGROUND: Development of robust treatment programs among core transmitters (CT) of hepatitis C virus (HCV) are needed, including strategies to address reinfection risk. The aim of this study was to describe the effectiveness of direct-acting antiviral (DAA) treatment in CT versus non-CT populations and assess reinfection rates after successful treatment. METHODS: Characterizing Risk Behaviour and Reinfection Rates for Successful Programs to Engage Core Transmitters in HCV Elimination (C-RESPECT) was a prospective, observational study of HCV-infected Canadian adult patients (genotypes 1, 3, and 4) treated with DAAs between 2017 and 2020. RESULTS: The full analysis set included 429 participants (259 CT, 170 non-CT). Key differences were observed in baseline profiles: CT participants were younger (mean 42.3 [SD 11.2] y versus 55.0 [SD 11.1] y, respectively) and reported higher rates of social assistance (35.7% versus 14.8%), smoking (83.7% versus 52.4%), low socioeconomic status (yearly income <$15,000: 69.6% versus 43.9%), illicit drug use (83.7% versus 34.3%), and previous incarcerations (62.7% versus 36.9%). DAA treatment adherence was similar; 93 .5% versus 98.3% of CT versus non-CT participants completed the assigned treatment duration. Cure rates (sustained virologic response) were comparable, ranging from 94.9% to 98.1%. All reinfections were among CT participants, with a rate of 13.8/100 person-years (95% CI 9.2–20.8) with mean time to reinfection of 24.6 (SD 0.6) months; CONCLUSIONS: CT and non-CT participants respond equally well to DAA treatment; however, with some reinfections among CT participants. Innovative multidisciplinary programs must be developed to mitigate this risk in this key population.

Understanding Variable Motor Responses to Direct Electrical Stimulation of the Human Motor Cortex During Brain Surgery

Direct electrical stimulation of the brain is the gold standard technique used to define functional-anatomical relationships during neurosurgical procedures. Areas that respond to stimulation are considered “critical nodes” of circuits that must remain intact for the subject to maintain the ability to perform certain functions, like moving and speaking. Despite its routine use, the neurophysiology underlying downstream motor responses to electrical stimulation of the brain, such as muscle contraction or movement arrest, is poorly understood. Furthermore, varying and sometimes counterintuitive responses can be seen depending on how and where the stimulation is applied, even within the human primary motor cortex. Therefore, here we review relevant neuroanatomy of the human motor system, provide a brief historical perspective on electrical brain stimulation, explore mechanistic variations in stimulation applications, examine neurophysiological properties of different parts of the motor system, and suggest areas of future research that can promote a better understanding of the interaction between electrical stimulation of the brain and its function.

Direct-acting antiviral treatment uptake and sustained virological response outcomes are not affected by alcohol use: A CANUHC analysis

BACKGROUND: Alcohol use and hepatitis C virus (HCV) are two leading causes of liver disease. Alcohol use is prevalent among the HCV-infected population and accelerates the progression of HCV-related liver disease. Despite barriers to care faced by HCV-infected patients who use alcohol, few studies have analyzed uptake of direct-acting antiviral (DAA) treatment. OBJECTIVE: We compared rates of treatment uptake and sustained virological response (SVR) between patients with and without alcohol use. METHODS: Prospective data were obtained from the Canadian Network Undertaking against Hepatitis C (CANUHC) cohort. Consenting patients assessed for DAA treatment between January 2016 and December 2019 were included. Demographic and clinical characteristics were compared between patients with and without alcohol use by means of t-tests, χ2 tests, and Fisher’s Exact Tests. Univariate and multivariate analyses were used to determine predictors of SVR and treatment initiation. RESULTS: Current alcohol use was reported for 217 of 725 (30%) patients. The proportion of patients initiating DAA treatment did not vary by alcohol use status (82% versus 83%; p = 0.99). SVR rate was similar between patients with alcohol use and patients without alcohol use (92% versus 94%; p = 0.45). Univariate and multivariate analysis found no association between alcohol use and SVR or treatment initiation. CONCLUSION: Patients engaged in HCV treatment have highly favourable treatment uptake and outcomes regardless of alcohol use. Public health interventions should be directed toward facilitating access to care for all patients irrespective of alcohol use. Research into high-level alcohol use and DAA outcomes is needed.

Salvage Therapy with Sofosbuvir/Velpatasvir/Voxilaprevir in DAA-experienced Patients: Results from a Prospective Canadian Registry

BACKGROUND

Despite the current highly effective therapies with direct-acting antiviral agents (DAAs), some patients with chronic hepatitis C virus (HCV) infection still do not achieve sustained virological response (SVR) and require retreatment. Sofosbuvir/velpatasvir/voxilaprevir (SVV) is recommended as the first-line retreatment option for most patients. The aim of this study was to evaluate the efficacy of SVV as salvage therapy after at least one course of DAA.

METHODS

Data were collected on all HCV-infected patients who failed DAAs and were prescribed SVV from a prospective Canadian registry (CANUHC) including 17 sites across Canada. Factors associated with failure to achieve SVR with SVV therapy and the utility of RAS testing and ribavirin use were evaluated.

RESULTS

A total of 128 patients received SVV after non-SVR with DAA treatment: 80% male, median age 57.5 (31-86), 44% cirrhotic, and 17 patients post liver transplant. First line regimens included: sofosbuvir/velpatasvir (27.3%), sofosbuvir/ledipasvir (26.5%), grazoprevir/elbasvir (12.5%), other (33.5%). Ribavirin was added to SVV in 26 patients due to past sofosbuvir/velpatasvir use (n = 8), complex resistance associated substitution profiles (n = 16) and/or cirrhosis (n = 9). Overall SVR rate was 96% (123/128). Of 35 patients who previously failed sofosbuvir/velpatasvir, 31 (88.5%) achieved SVR compared to 92 of 93 (99%) among those receiving any other regimen (P = .01).

CONCLUSIONS

Similar to reports from phase 3 clinical trials, SVV proved highly effective as salvage therapy for patients who failed a previous DAA therapy. Those who failed SVV had at least 2 of the following factors: genotype 3, presence of cirrhosis, past liver transplantation, past exposure to sofosbuvir/velpatasvir and/or complex resistance profiles.

Effectiveness and Renal Safety of Tenofovir Alafenamide Fumarate among Chronic Hepatitis B Patients: Real-World Study

Tenofovir alafenamide fumarate (TAF) has high plasma stability resulting in fewer renal adverse events compared to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. We aimed to study the effectiveness and renal safety of TAF in a real-world setting, in patients with or without compromised kidney function. CHB patients (Nucleos(t)ide Analogue [NA]-naïve or experienced) who received TAF >1 year from 11 academic institutions as part of the Canadian Hepatitis B Network (CanHepB) were included. Kidney function was measured by estimated glomerular filtration rate (eGFR) as per Cockcroft-Gault. Patients were followed for up to 160 weeks. Of 176 patients receiving TAF, 143 switched from NA (88% TDF), and 33(19%) were NA naïve. Majority of NA-naïve patients (75%) achieved undetectable HBV DNA after one year of TAF treatment. Majority of patients with eGFR <60 mL/min who had renal deterioration during TDF (76%) reversed to eGFR increase after one year of TAF (p=0.009). Among patients with stage 2 chronic kidney disease (CKD) (eGFR 60-89), the estimated eGFR decline during TDF was halted after switching to TAF (p=0.09). NA-experienced patients with abnormal ALT before TAF showed a significant decline after switching to TAF: -0.005 [-0.006 - -0.004] log₁₀ ULN U/L/month, p<0.001). In CHB patients, TAF was safe, well-tolerated and effective in this real-world cohort. Switching to TAF led to improved kidney function, particularly in those with stage 2 CKD, which suggests that the indication for TAF in the guidelines could be extended to patients with an eGFR higher than 60 mL/min.

Reinfection Following Successful Direct-acting Antiviral Therapy for Hepatitis C Virus Infection Among People Who Inject Drugs

BACKGROUND

The aim of this analysis was to calculate the incidence of hepatitis C virus (HCV) reinfection and associated factors among 2 clinical trials of HCV direct-acting antiviral treatment in people with recent injecting drug use or currently receiving opioid agonist therapy (OAT).

METHODS

Participants who achieved an end-of-treatment response in 2 clinical trials of people with recent injecting drug use or currently receiving OAT (SIMPLIFY and D3FEAT) enrolled between March 2016 and February 2017 in 8 countries were assessed for HCV reinfection, confirmed by viral sequencing. Incidence was calculated using person-time of observation and associated factors were assessed using Cox proportional hazard models.

RESULTS

Seventy-three percent of the population at risk of reinfection (n = 177; median age, 48 years; 73% male) reported ongoing injecting drug use. Total follow-up time at risk was 254 person-years (median, 1.8 years; range, 0.2-2.8 years). Eight cases of reinfection were confirmed for an incidence of 3.1/100 person-years (95% confidence interval [CI], 1.6-6.3) overall and 17.9/100 person-years (95% CI, 5.8-55.6) among those who reported sharing needles/syringes. Younger age and needle/syringe sharing were associated with HCV reinfection.

CONCLUSIONS

These data demonstrate the need for ongoing monitoring and improved strategies to prevent HCV reinfection following successful treatment among people with ongoing injecting drug use to achieve HCV elimination.

CLINICAL TRIALS REGISTRATION

NCT02336139 and NCT02498015.

O45: DEFINING CELL-ENRICHED MICRORNAS TO SUPPORT RATIONAL BIOMARKER SELECTION IN HUMAN RENAL TRANSPLANTATION

Introduction

MicroRNAs are promising biomarkers of renal disease, however the cellular origin of their expression is usually unclear limiting their interpretation when measured in renal biopsies and urine. We hypothesised that by first defining renal cell-enriched microRNAs, we could select biomarkers based on the expected histopathological profile.

Method

Small RNA-sequencing of cortical, proximal tubular (LTL), macrophage (F480), endothelial (CD31) and fibroblast (PDGFRb) populations from the reversible unilateral ureteric obstruction (rUUO) murine model was performed. Hierarchical clustering was used to identify clusters. Findings were translated into an ischaemia reperfusion injury (IRI) model and then into urine samples from renal transplant recipients (n=16) with delayed graft function (DGF) vs. those with primary function.

Result

Kidney injury resulted in significant macrophage infiltration and tubular injury which improved upon reversal. We characterised novel microRNA clusters enriched for each cell type. With injury there was a significant increase in macrophage (p&lt;0.0001), fibroblast (p&lt;0.01) and decrease in proximal tubule (p&lt;0.0001) enriched microRNAs vs. non-enriched microRNAs. We validated macrophage enriched miR-18a, miR-16 and tubular enriched miR-194 in the IRI model, demonstrating that microRNA expression reflected the histological profile. In humans, urinary miR-16 (FC 16.9; p&lt;0.05) and miR-18a (FC 10: p=0.06) were upregulated at day 2 in patients with DGF; outperforming the traditional injury marker KIM1.

Conclusion

This is the first study to characterise cell-enriched microRNAs during renal injury and repair. By defining the source of microRNA expression we were able to rationally select miR-16 and miR-18a as promising urinary biomarkers of renal injury.

Take-home message

We have found that microRNAs have differences in expression between cell types and renal injury states which is important when considering microRNA expression in samples composed of varying cellular composition. By defining the cellular origins of microRNA expression we were able to rationally select microRNA biomarkers of human renal injury.

Late presentation of myocardial infarction (MI) during the COVID-19 pandemic

A 65-year-old man presented to emergency department with progressive worsening dyspnoea, which was preceded by crushing, substernal chest pain 3 weeks prior that lasted for over 2 days. At the time the patient thought that this was a symptom of COVID-19 so he stayed at home and self-quarantined, until his symptoms worsened to the point of needing hospitalisation. The patient was found to have had myocardial infarction, with coronary angiography showing 100% occlusion of the Left Anterior Descending artery (LAD). Medical management was recommended given late presentation and risk of reperfusion injury.

Distinct Hepatitis B and HIV co-infected populations in Canada

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care.

Characterization of HCV-infected people who inject drugs (PWID) in the setting of clinical care in Canada (CAPICA): A retrospective study

BACKGROUND: People who use drugs (PWUD) are among the highest risk category for becoming infected with the hepatitis C virus (HCV) in Canada. There is a need for more information on the demographics of HCV-infected PWUD/PWID who have recently injected drugs or who are actively injecting drugs. METHODS: CAPICA was a multicentre, retrospective database/chart review conducted from October 2015 to February 2016 that was designed to characterize HCV-infected people who inject drugs (PWID) and are enrolled in clinical care in Canada. The aim was to identify factors of health care engagement essential in the design systems of HCV care and treatment in this population. The study enrolled 420 patients with a history of injection drug use within the last 12 months who had been diagnosed with chronic viremic HCV infection and had been participants in an outpatient clinical care setting in the past 12 months. Patients who were co-infected with HIV/HCV were excluded. RESULTS: Harm reduction programs were in place at 92% (11/12) of the sites, and 75% (9) of these sites offered opioid agonist therapy (OAT), with 48% of the patients currently taking OAT. HCV genotype 1a was most prevalent (56%), followed by G3 (34%), and the most common fibrosis score was F1 (34%). The average reinfection rate was about 5%. Seventeen percent of the patients were undergoing HCV treatment or had recently failed therapy, while 83% were not being treated. CONCLUSIONS: In a multivariate analysis, the following factors were significantly associated with treatment: increasing age (OR 1.10), a fibrosis score of F4 (OR 4.91), moderate alcohol consumption (OR 3.70), and not using a needle exchange program (OR 6.95).

Hepatitis C virus infection characteristics and treatment outcomes in Canadian immigrants

BACKGROUND

There are multiple obstacles encountered by immigrants attempting to engage hepatitis C virus (HCV) care and treatment. We evaluated the diversity and treatment outcomes of HCV-infected immigrants evaluated for Direct Acting Antiviral (DAA) therapy in Canada.

METHODS

The Canadian Network Undertaking against Hepatitis C (CANUHC) Cohort contains demographic information and DAA treatment information prospectively collected at 10 Canadian sites. Information on country of origin and race are collected. Characteristics and outcomes (sustained virological response; SVR) were compared by immigration status and race.

RESULTS

Between January 2016 and May 2018, 725 HCV-infected patients assessed for DAA therapy were enrolled in CANUHC (mean age: 52.66 ± 12.68 years); 65.66% male; 82.08% White, 5.28% Indigenous, 4.64% South East Asian, 4.64% East Indian, 3.36% Black). 18.48% were born outside of Canada. Mean age was similar [immigrants: 54.36 ± 13.95 years), Canadian-born: 52.27 ± 12.35 years); (p = 0.085)]. The overall baseline fibrosis score (in kPa measured by transient elastography) was similar among Canadian and foreign-born patients. Fibrosis score was not predicted by race or genotype. The proportion initiating DAA therapy was similar by immigrant status (56.72% vs 49.92%). SVR rates by intent-to-treat analysis were similar (immigrants-89.47%, Canadian-born-92.52%; p = 0.575).

CONCLUSION

A diverse immigrant population is engaging care in Canada, initiating HCV antiviral therapy in an equitable fashion and achieving SVR proportions similar to Canada-born patients. Our Canadian experience may be of value in informing HCV elimination efforts in economically developed regions.

The Z-Profile Study: a multicenter, retrospective cohort study to assess the real-world use and effectiveness of elbasvir/grazoprevir in Canadian adult patients with chronic hepatitis C

Background: Canada was the first country to approve elbasvir/grazoprevir (EBR/GZR) for the treatment of chronic HCV infection for genotypes 1 and 4 with or without ribavirin and genotype 3 with sofosbuvir, with no recommendation for baseline resistance testing. The aim of this study was to describe the effectiveness of EBR/GZR and the profile of patients selected for treatment in a Canadian real-world setting. Methods: This multicenter retrospective study of HCV-infected patients treated with EBR/GZR took place among selected Canadian health care providers, with no exclusion criteria. Primary outcome measures included parameters associated with patient profile and sustained virologic response at 12 weeks (SVR12) and 24 weeks after treatment. Results: A total of 408 patients were included; 244 had available SVR12 information (per-protocol population [PP]). Genotype distribution included 1a (54.7%), 1b (17.2%), 3 (11.8%), 4 (10.0%), and other (6.4%). The majority (88.7%) of participants were treated for 12 weeks without ribavirin. Fifty-nine (14.5%) participants, predominantly with genotype 1a (49/59) infection, were tested for baseline resistance-associated substitutions (bRAS). SVR12 was achieved by 95.9% of the PP. In an exploratory analysis assessing potential predictors of SVR12, participants who had undergone bRAS testing (OR 0.14, 95% CI 0.03–0.64) and participants who had undergone liver transplant (OR 0.05, 95% CI 0.00–0.68) had significantly lower odds of achieving SVR12. Conclusions: This study supports the real-world effectiveness of EBR/GZR—including a broad range of genotypes and diverse fibrosis stages—in the absence of bRAS testing and in special populations.

Eliminating Structural Barriers: The Impact of Unrestricted Access on Hepatitis C Treatment Uptake Among People Living With Human Immunodeficiency Virus

BACKGROUND

High costs of direct-acting antivirals (DAAs) have led health-care insurers to limit access worldwide. Using a natural experiment, we evaluated the impact of removing fibrosis stage restrictions on hepatitis C (HCV) treatment initiation rates among people living with human immunodeficiency virus (HIV), and then examined who was left to be treated.

METHODS

Using data from the Canadian HIV-HCV Coinfection Cohort, we applied a difference-in-differences approach. Changes in treatment initiation rates following the removal of fibrosis stage restrictions were assessed using a negative binomial regression with generalized estimating equations. The policy change was then specifically assessed among people who inject drugs (PWID). We then identified the characteristics of participants who remained to be treated using a modified Poisson regression.

RESULTS

Between 2010-2018, there were a total of 585 HCV initiations among 1130 eligible participants. After removing fibrosis stage restrictions, DAA initiations increased by 1.8-fold (95% confidence interval [CI] 1.3-2.4) controlling for time-invariant differences and secular trends. Among PWID the impact appeared even stronger, with an adjusted incidence rate ratio of 3.6 (95% CI 1.8-7.4). However, this increased treatment uptake was not sustained. At 1 year following universal access, treatment rates declined to 0.8 (95% CI .5-1.1). Marginalized participants (PWID and those of indigenous ethnicity) and those disengaged from care were more likely to remain HCV RNA positive.

CONCLUSIONS

After the removal of fibrosis restrictions, HCV treatment initiations nearly doubled immediately, but this treatment rate was not sustained. To meet the World Health Organization elimination targets, the minimization of structural barriers and adoption of tailored interventions are needed to engage and treat all vulnerable populations.

Patterns of Drug and Alcohol Use and Injection Equipment Sharing Among People With Recent Injecting Drug Use or Receiving Opioid Agonist Treatment During and Following Hepatitis C Virus Treatment With Direct-acting Antiviral Therapies: An International Study

BACKGROUND

In many settings, recent or prior injection drug use remains a barrier to accessing direct-acting antiviral treatment (DAA) for hepatitis C virus (HCV) infection. We examined patterns of drug and alcohol use and injection equipment sharing among people with recent injecting drug use or receiving opioid agonist treatment (OAT) during and following DAA-based treatment.

METHODS

SIMPLIFY and D3FEAT are phase 4 trials evaluating the efficacy of DAA among people with past 6-month injecting drug use or receiving OAT through a network of 25 international sites. Enrolled in 2016-2017, participants received sofosbuvir/velpatasvir (SIMPLIFY) or paritaprevir/ritonavir/dasabuvir/ombitasvir ± ribavirin (D3FEAT) for 12 weeks and completed behavioral questionnaires before, during, and up to 2 years posttreatment. The impact of time in HCV treatment and follow-up on longitudinally measured longitudinally measured behaviors was estimated using generalized estimating equations.

RESULTS

At screening, of 190 participants (mean age, 47 years; 74% male), 62% reported any past-month injecting 16% past-month injection equipment sharing, and 61% current OAT. Median alcohol use was 2 (Alcohol Use Disorders Identification Test-Consumption; range, 1-12). During follow-up, opioid injecting (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.92-0.99) and sharing (OR, 0.87; 95% CI, 0.80-0.94) decreased, whereas no significant changes were observed for stimulant injecting (OR, 0.98; 95% CI, 0.94-1.02) or alcohol use (OR, 0.99; 95% CI, 0.95-1.04).

CONCLUSIONS

Injecting drug use and risk behaviors remained stable or decreased following DAA-based HCV treatment. Findings further support expanding HCV treatment to all, irrespective of injection drug use.

CLINICAL TRIALS REGISTRATION

SIMPLIFY, NCT02336139; D3FEAT, NCT02498015.

Adherence to pan-genotypic glecaprevir/pibrentasvir and efficacy in HCV-infected patients: A pooled analysis of clinical trials

BACKGROUND & AIMS

Adequate adherence to hepatitis C virus (HCV) treatment is believed to be a key component of treatment success because non-adherence can potentially result in treatment failure and the emergence of resistant viral variants. This analysis assessed factors associated with non-adherence to glecaprevir/pibrentasvir (G/P) therapy and the impact of non-adherence on sustained virological response at post-treatment week 12 (SVR12) rates in HCV genotype (GT) 1-6-infected patients.

METHODS

Adherence was calculated by pill counts at study visits during treatment, and defined as having a lowest treatment adherence of ≥80% and ≤120% at each study visit. Exploratory logistic regression modelling assessed predictors of non-adherence to G/P therapy. SVR12 rates by treatment adherence were assessed in the intent-to-treat (ITT) population and modified ITT (mITT) population, which excludes non-virological failures.

RESULTS

Overall, 97% (2024/2091) of patients were adherent to G/P therapy at all consecutive study visits. Alcohol use was the only baseline characteristic independently associated with non-adherence to G/P therapy (OR: 2.38; 95% CI: 1.13-5.01; P = .022). In the mITT population, overall SVR12 rates were high both in patients who were adherent to G/P therapy and those who were not (99% [1983/2008] and 95% [58/61] respectively; P = .047). Corresponding SVR12 rates in the ITT population were 98% (1983/2024) and 87% (58/67) respectively.

CONCLUSIONS

Most patients adhered to G/P therapy. SVR12 rates were high both in patients who were adherent to G/P treatment and those who were not. Patient education on treatment adherence should remain an important part of HCV treatment.

CLINICAL TRIALS REGISTRATION

NCT02604017, NCT02640482, NCT02640157, NCT02636595, NCT02642432, NCT02651194, NCT02243293, NCT02446717.

Glecaprevir/pibrentasvir+sofosbuvir: an optimal retreatment strategy in the setting of HCV NS5A resistance

Some individuals do not achieve a cure of their hepatitis C virus (HCV) infection due to non-adherence or resistance associated substitutions. Salvage options that are optimised for resistance profiles are essential. We report a 56-year-old Caucasian man with fatigue, depression and confusion in the setting of untreated HCV genotype 3a infection. He received ruzasvir and uprifosbuvir for 12 weeks within a clinical trial. The patient relapsed 4 weeks after the end of treatment and at this time resistance testing showed multiple resistances including a NS5A Y93H mutation. Given that this mutation confers resistance to first line salvage options, sofosbuvir and glecaprevir/pibrentasvir was used for 12 weeks and the patient was cured of HCV infection 12 weeks after the end of treatment. This shows that sofosbuvir and glecaprevir/pibrentasvir is a viable, effective option for second line/salvage therapy of HCV infection in the setting of resistance to NS5A inhibitors with the Y93H mutation.

Week 48 Resistance Analyses of the Once-Daily, Single-Tablet Regimen Darunavir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (D/C/F/TAF) in Adults Living with HIV-1 from the Phase III Randomized AMBER and EMERALD Trials

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg is being investigated in two Phase III trials, AMBER (NCT02431247; treatment-naive adults) and EMERALD (NCT02269917; treatment-experienced, virologically suppressed adults). Week 48 AMBER and EMERALD resistance analyses are presented. Postbaseline samples for genotyping/phenotyping were analyzed from protocol-defined virologic failures (PDVFs) with viral load (VL) ≥400 copies/mL at failure/later time points. Post hoc analyses were deep sequencing in AMBER, and HIV-1 proviral DNA from baseline samples (VL <50 copies/mL) in EMERALD. Through week 48 across both studies, no darunavir, primary PI, or tenofovir resistance-associated mutations (RAMs) were observed in HIV-1 viruses of 1,125 participants receiving D/C/F/TAF or 629 receiving boosted darunavir plus emtricitabine/tenofovir-disoproxil-fumarate. In AMBER, the nucleos(t)ide analog reverse transcriptase inhibitor (N(t)RTI) RAM M184I/V was identified in HIV-1 of one participant during D/C/F/TAF treatment. M184V was detected pretreatment as a minority variant (9%). In EMERALD, in participants with prior VF and genoarchive data (N = 140; 98 D/C/F/TAF and 42 control), 4% had viruses with darunavir RAMs, 38% with emtricitabine RAMs, mainly at position 184 (41% not fully susceptible to emtricitabine), 4% with tenofovir RAMs, and 21% ≥ 3 thymidine analog-associated mutations (24% not fully susceptible to tenofovir) detected at screening. All achieved VL <50 copies/mL at week 48 or prior discontinuation. D/C/F/TAF has a high genetic barrier to resistance; no darunavir, primary PI, or tenofovir RAMs were observed through 48 weeks in AMBER and EMERALD. Only one postbaseline M184I/V RAM was observed in HIV-1 of an AMBER participant. In EMERALD, baseline archived RAMs to darunavir, emtricitabine, and tenofovir in participants with prior VF did not preclude virologic response.

Adherence to Once-daily and Twice-daily Direct-acting Antiviral Therapy for Hepatitis C Infection Among People With Recent Injection Drug Use or Current Opioid Agonist Therapy

Background

This study investigated adherence and associated factors among people with recent injection drug use (IDU) or current opioid agonist therapy (OAT) and compared once-daily to twice-daily hepatitis C virus (HCV) direct-acting antiviral (DAA) therapy.

Methods

SIMPLIFY and D3FEAT are international, multicenter studies that recruited participants with recent IDU (previous 6 months; SIMPLIFY, D3FEAT) or current OAT (D3FEAT) between March 2016 and February 2017 in 8 countries. Participants received sofosbuvir/velpatasvir (once daily; SIMPLIFY) or paritaprevir/ritonavir/ombitasvir, dasabuvir (twice daily) ± ribavirin (D3FEAT) for 12 weeks administered in electronic blister packs. We evaluated overall adherence (proportion of prescribed doses taken) and nonadherence (&lt;90% adherent) between dosing patterns.

Results

Of 190 participants, 184 (97%) completed treatment. Median adherence was 92%, with higher adherence among those receiving once-daily vs twice-daily therapy (94% vs 87%, P = .005). Overall, 40% of participants (n = 76) were nonadherent (&lt;90% adherent). Recent stimulant injecting (odds ratio [OR], 2.48 [95% confidence interval {CI}, 1.28–4.82]), unstable housing (OR, 2.18 [95% CI, 1.01–4.70]), and twice-daily dosing (OR, 2.81 [95% CI, 1.47–5.36]) were associated with nonadherence. Adherence decreased during therapy. Sustained virologic response was high in nonadherent (89%) and adherent populations (95%, P = .174), with no difference in SVR between those who did and did not miss 7 consecutive doses (92% vs 93%, P = .897).

Conclusions

This study demonstrated high adherence to once- and twice-daily DAA therapy among people with recent IDU or currently receiving OAT. Nonadherence described did not impact treatment outcomes, suggesting forgiveness to nonadherence.

Sofosbuvir and velpatasvir in the treatment of chronic hepatitis C

Advances in hepatitis C virus (HCV) treatment led to the development of highly effective all oral direct acting antiviral regimens. The combination of sofosbuvir and velpatasvir (SOF/VEL), two agents acting synergistically at different stages in the viral life cycle, has been evaluated in a broad range of clinical trials supporting its efficacy in complex and diverse patient populations. Following regulatory approval in 2016, SOF/VEL has been widely used as a safe, effective pangenotypic regimen in clinical practice. In this review, we will discuss the current preclinical, clinical and real-world data on SOF/VEL.

Epidemiologic and clinical features of chronic hepatitis B virus infection in 8 Canadian provinces: a descriptive study by the Canadian HBV Network

BACKGROUND

Published Canadian epidemiologic data on hepatitis B virus (HBV) infection include single-centre studies or are focused on Indigenous populations. We performed a study to characterize the demographic and clinical features, liver disease status and treatment of people with chronic hepatitis B in Canada.

METHODS

In this descriptive, opportunistic, cross-sectional study, available data for people known to be monoinfected with HBV were collected by the Canadian HBV Network from existing clinical databases, with support from the National Microbiology Laboratory, Public Health Agency of Canada. Data were collected in all provinces with the exception of New Brunswick and Newfoundland and Labrador. We analyzed the data using parametric and nonparametric statistical methods, with a significance level of p < 0.05.

RESULTS

In the 9380 unique patient records reviewed, the median age was 48 years, and 5193 patients (55.4%) were male. Ethnicity information was available for 7858 patients, of whom 5803 (73.8%) were Asian, 916 (11.6%) were black and 914 (11.6%) were white. Most of those tested (5556/6796 [81.8%]) were negative for HBV e-antigen, and most of those with fibrosis data (3481/4260 [81.7%]) had minimal liver fibrosis, with more advanced fibrosis noted in older people (> 40 yr). Of the 980 patients with genotype data, 521 (53.2%) had genotype B or C infection. Most of the 9241 patients with known confirmed treatment status received tenofovir disoproxil fumarate (1655 [17.9%]), lamivudine (1434 [15.5%]) or entecavir (548 [5.9%]).

INTERPRETATION

Based on available data, Canadian patients with chronic hepatitis B are predominantly Asian and negative for HBV e-antigen, and have genotype B or C infection. Interprovincial variations were noted in antiviral treatment regimen. This multicentre nationwide study provides data regarding patients with chronic hepatitis B and may inform future studies on the epidemiologic features of HBV infection in Canada.

Low rate of reinfection among a cohort of people who use drugs successfully treated for hepatitis C virus infection in Vancouver, Canada

INTRODUCTION

Concerns about reinfection may be limiting HCV treatment uptake among people who use drugs (PWUD), with rates of 17.1/100 person-years in some cohorts. The aim of this study was to evaluate reinfection following successful treatment for hepatitis C virus infection in a cohort of people who inject drugs in Vancouver, Canada.

METHODS

We identified a cohort of HCV-infected PWUD treated at our centre. Following cure, patients were maintained in long-term follow-up in a multidisciplinary program to address their medical, psychological, social, and addiction-related needs. HCV RNA measurements were repeated every 6 months, and ongoing drug use was documented. The primary outcome of this analysis was the occurrence of reinfection.

RESULTS

243 recent PWUD (use within 6 months of treatment initiation) have achieved SVR and maintained in long-term follow-up. Ongoing drug use post-treatment was documented in 195 individuals. Key characteristics: mean age 53 years, 25% female, 78% treatment naïve, 17% cirrhotic. Reinfection occurred in 4 cases, all in patients with ongoing drug use. This incidence was 1.05/100 [95% 0.8-5.2] person years based on 379 person-years of follow-up in individuals currently using drugs.

CONCLUSION

Approaches including long-term maintenance in multidisciplinary care may optimize long-term outcomes of HCV treatment in PWUD.

HCV elimination and the opioid crisis – joint epidemics, joint solutions: results of a pilot program

Aim: People who use drugs in Canada are disproportionately affected by both the HCV and opioid overdose epidemics. It is feasible to envision a solution to address both issues simultaneously. Methodology: A retrospective chart review of HCV-infected patients with a history of drug use was conducted. All patients enrolled at our center have access to multidisciplinary care to address medical, social, psychiatric and addictions-related needs in an integrated manner. Results: Since 2014, 337 individuals have initiated HCV treatment, in whom 30 medically significant overdoses have occurred, including three deaths. Conclusion: The model we have developed could be an ideal approach to address HCV, as well as respond to the opioid crisis, in a high-risk population.

Safety and efficacy of glecaprevir/pibrentasvir in patients with chronic hepatitis C genotypes 1-6 receiving opioid substitution therapy

BACKGROUND

International guidelines recommend treatment of hepatitis C virus (HCV) infection in people who inject drugs (PWID), including those on opioid substitution therapy (OST). The pangenotypic combination of glecaprevir and pibrentasvir has shown high sustained virologic response at post-treatment Week 12 (SVR12) in clinical trials. Herein, we evaluate the safety and efficacy of glecaprevir/pibrentasvir in patients receiving OST.

METHODS

Pooled data from patients with HCV genotypes 1-6 who were treated with glecaprevir/pibrentasvir for 8, 12, or 16 weeks in eight Phase 2 and 3 trials were categorized by use of OST. Treatment completion, treatment adherence, SVR12, adverse events (AEs), and laboratory abnormalities were evaluated for patients receiving and not receiving OST.

RESULTS

Among 2256 patients, 157 (7%) were receiving OST. Compared with patients not receiving OST, OST patients were younger (mean age, 46.8 vs 52.8 years), male (69% vs 54%), white (93% vs 80%), HCV treatment-naïve (86% vs 72%), had HCV genotype 3 (60% vs 26%), and had a history of depression or bipolar disorder (43% vs 19%). Most patients completed (OST: 98% [n/N = 154/157]; non-OST: 99% [n/N = 2070/2099]) and were adherent (received ≥90% of study drug doses) to glecaprevir/pibrentasvir treatment (OST: 98% [n/N = 121/123]; non-OST: 99% [n/N = 1884/1905] among patients with available data). In the intention-to-treat population, SVR12 rates in OST and non-OST patients were 96.2% (n/N = 151/157; 95% CI 93.2-99.2) and 97.9% (n/N = 2055/2099; 95% CI 97.3-98.5), respectively. For OST patients, reasons for nonresponse included virologic relapse (<1%; n = 1), premature study drug discontinuation (<1%; n = 1), and loss to follow-up (3%; n = 4). AEs occurring in ≥10% of OST patients were headache, fatigue, and nausea. Drug-related serious AEs, AEs leading to study drug discontinuation, and Grade 3 or higher laboratory abnormalities were infrequent in both groups (<1%). No HCV reinfections occurred through post-treatment Week 12.

CONCLUSION

Glecaprevir/pibrentasvir is highly efficacious and well tolerated in HCV-infected patients receiving OST.

Glecaprevir/pibrentasvir in patients with chronic HCV and recent drug use: An integrated analysis of 7 phase III studies

BACKGROUND

Injection drug use is the primary mode of transmission for hepatitis C virus (HCV), and treatment guidelines recommend treating HCV-infected people who use drugs; however, concerns about adherence, effectiveness, and reinfection have impeded treatment uptake.

METHODS

Data were pooled from seven phase III trials that evaluated the efficacy and safety of 8 or 12 weeks of glecaprevir/pibrentasvir (G/P) in patients chronically infected with HCV genotypes 1-6. Patients had compensated liver disease, with or without cirrhosis, and were HCV treatment-naïve or -experienced with interferon or pegylated interferon ± ribavirin, or sofosbuvir plus ribavirin ± pegylated interferon. Patients were grouped into recent drug users (injection drug use ≤12 months before screening, positive urine drug screen [UDS], and/or drug-related adverse event), former drug users (>12 months before screening and negative UDS), or non-drug users. Assessments included sustained virologic response at 12 weeks posttreatment (SVR12), treatment adherence, and safety.

RESULTS

Among 1819 patients, 5%, 34%, and 61% were recent, former, and non-drug users, respectively. Treatment adherence and completion were high (≥96%) regardless of drug use status. SVR12 was achieved by 93% (n/N = 91/98), 97% (n/N = 591/610), and >99% (n/N = 1106/1111) of recent, former, and non-drug users, respectively (intention-to-treat analysis). The overall rates of virologic failure were ≤1.5% across all three subpopulations, with no HCV reinfections among recent drug users. Drug-related serious adverse events and adverse events leading to treatment discontinuation were experienced by ≤1% of patients.

CONCLUSIONS

G/P is a well-tolerated and efficacious pangenotypic regimen for chronic HCV-infected people with recent or active drug use.

Adherence to sofosbuvir and velpatasvir among people with chronic HCV infection and recent injection drug use: The SIMPLIFY study

BACKGROUND

This study investigated treatment adherence among people with recent injecting drug use in a study of sofosbuvir/velpatasvir therapy for HCV infection.

METHODS

SIMPLIFY is an international open-label, single-arm multicentre study that recruited participants with recent injecting drug use (previous six months) and chronic HCV genotype (G) 1-6 infection between March and October 2016 in seven countries (19 sites). Participants received sofosbuvir/velpatasvir once-daily for 12 weeks administered in a one-week electronic blister pack (records the time and date of each dose) for 12 weeks. We evaluated non-adherence (<90% adherent) as measured by electronic blister-pack assessed using logistic regression and generalised estimating equations (continuous) with detailed analyses of dosing dynamics.

RESULTS

Among 103 participants, 97% (n = 100) completed treatment. Median adherence to therapy was 94%. Overall, 32% (n = 33) were considered non-adherent (<90% adherence). Adherence significantly decreased over the course of therapy. Recent stimulant injecting (cocaine and/or amphetamines) at treatment initiation and during treatment was independently associated with non-adherence. Inconsistent dose timing (standard deviation of daily dose timing of ≥240 min) was also independently associated with non-adherence to therapy. Factors associated with inconsistent dose timing included lower levels of education and recent stimulant injecting. SVR was similar among adherent and non-adherent populations (94% vs. 94%, P = 0.944).

CONCLUSION

This study demonstrated high adherence to once-daily sofosbuvir/velpatasvir therapy among a population of people with recent injecting drug use. Recent stimulant injecting prior to and during DAA therapy and inconsistent dose-timing during treatment was associated with non-adherence. However, there was no impact of non-adherence on response to therapy, suggesting that adherence is not a significant barrier to successful DAA therapy in people with recent injecting drug use.

Daclatasvir, asunaprevir and beclabuvir fixed-dose combination for patients with genotype 1 chronic hepatitis C

Hepatitis C is killing 350,000 persons per year worldwide, 60% of the cases being patients with genotype 1 (GT-1). The fixed-dose tablet combination of daclatasvir (30 mg)/asunaprevir (200 mg)/beclabuvir (75 mg), DCV-TRIO, is one of the latest drugs in the pipeline of interferon-free direct-acting antiviral hepatitis C virus (HCV) therapies. DCV-TRIO increases the genetic barrier to resistance by acting at the same time against three hepatitis C key viral proteins. Results from the UNITY 1, 2, 3 and 4 phase III clinical trials showed that DCV-TRIO exhibited high sustained virologic responses at 12 weeks (between 92% and 100% for HCV GT-1 treatment-naive patients). Furthermore, DCV-TRIO was well tolerated in all studies with reported adverse events (AEs) with an incidence of at least 10% mostly being headache, diarrhea, fatigue and nausea and few AE-related discontinuations. Further research should focus on more real-life data on DCV-TRIO and on developing a pill regimen that works on other HCV genotypes with high genetic barriers and that is available at a reduced cost.