Journal Article > ResearchFull Text
J Hepatol. 2019 February 21; Volume 71 (Issue 1); 62-70.; DOI:https://doi.org/10.1016/j.jhep.2019.02.011
Freiman JM, Wang J, Easterbrook PJ, Horsburgh CR, Marinucci F, et al.
J Hepatol. 2019 February 21; Volume 71 (Issue 1); 62-70.; DOI:https://doi.org/10.1016/j.jhep.2019.02.011
BACKGROUND & AIMS
Affordable point-of-care tests for hepatitis C (HCV) viraemia are needed to improve access to treatment in low- and middle-income countries. Our aims were to determine the target limit of detection (LOD) necessary to diagnose the majority of people with HCV eligible for treatment, and identify characteristics associated with low-level viraemia (LLV) (defined as the lowest 3% of the distribution of HCV RNA) to understand those at risk of being misdiagnosed.
METHODS
We established a multi-country cross-sectional dataset of first available quantitative HCV RNA measurements linked to demographic and clinical data. We excluded individuals on HCV treatment. We analysed the distribution of HCV RNA and determined critical thresholds for detection of HCV viraemia. We then performed logistic regression to evaluate factors associated with LLV, and derived relative sensitivities for significant covariates.
RESULTS
The dataset included 66,640 individuals with HCV viraemia from across the world. The LOD for the 95th and 99th percentiles were 3,311 IU/ml and 214 IU/ml. The LOD for the 97th percentile was 1,318 IU/ml (95% CI 1,298.4–1,322.3). Factors associated with LLV, defined as HCV RNA <1,318 IU/ml, were younger age 18–30 vs. 51–64 years (odds ratios [OR] 2.56; 95% CI 2.19–2.99), female vs. male sex (OR 1.32; 95% CI 1.18–1.49), and advanced fibrosis stage F4 vs. F0-1 (OR 1.44; 95% CI 1.21–1.69). Only the younger age group had a decreased relative sensitivity below 95%, at 93.3%.
CONCLUSIONS
In this global dataset, a test with an LOD of 1,318 IU/ml would identify 97% of viraemic HCV infections among almost all populations. This LOD will help guide manufacturers in the development of affordable point-of-care diagnostics to expand HCV testing and linkage to care in low- and middle-income countries.
LAY SUMMARY
We created and analysed a dataset from 12 countries with 66,640 participants with chronic hepatitis C virus infection. We determined that about 97% of those with viraemic infection had 1,300 IU/ml or more of circulating virus at the time of diagnosis. While current diagnostic tests can detect as little as 12 IU/ml of virus, our findings suggest that increasing the level of detection closer to 1,300 IU/ml would maintain good test accuracy and will likely enable development of more affordable portable tests for use in low- and middle-income countries.
Affordable point-of-care tests for hepatitis C (HCV) viraemia are needed to improve access to treatment in low- and middle-income countries. Our aims were to determine the target limit of detection (LOD) necessary to diagnose the majority of people with HCV eligible for treatment, and identify characteristics associated with low-level viraemia (LLV) (defined as the lowest 3% of the distribution of HCV RNA) to understand those at risk of being misdiagnosed.
METHODS
We established a multi-country cross-sectional dataset of first available quantitative HCV RNA measurements linked to demographic and clinical data. We excluded individuals on HCV treatment. We analysed the distribution of HCV RNA and determined critical thresholds for detection of HCV viraemia. We then performed logistic regression to evaluate factors associated with LLV, and derived relative sensitivities for significant covariates.
RESULTS
The dataset included 66,640 individuals with HCV viraemia from across the world. The LOD for the 95th and 99th percentiles were 3,311 IU/ml and 214 IU/ml. The LOD for the 97th percentile was 1,318 IU/ml (95% CI 1,298.4–1,322.3). Factors associated with LLV, defined as HCV RNA <1,318 IU/ml, were younger age 18–30 vs. 51–64 years (odds ratios [OR] 2.56; 95% CI 2.19–2.99), female vs. male sex (OR 1.32; 95% CI 1.18–1.49), and advanced fibrosis stage F4 vs. F0-1 (OR 1.44; 95% CI 1.21–1.69). Only the younger age group had a decreased relative sensitivity below 95%, at 93.3%.
CONCLUSIONS
In this global dataset, a test with an LOD of 1,318 IU/ml would identify 97% of viraemic HCV infections among almost all populations. This LOD will help guide manufacturers in the development of affordable point-of-care diagnostics to expand HCV testing and linkage to care in low- and middle-income countries.
LAY SUMMARY
We created and analysed a dataset from 12 countries with 66,640 participants with chronic hepatitis C virus infection. We determined that about 97% of those with viraemic infection had 1,300 IU/ml or more of circulating virus at the time of diagnosis. While current diagnostic tests can detect as little as 12 IU/ml of virus, our findings suggest that increasing the level of detection closer to 1,300 IU/ml would maintain good test accuracy and will likely enable development of more affordable portable tests for use in low- and middle-income countries.
Journal Article > ResearchFull Text
J Viral Hepat. 2022 March 12; Online ahead of print; DOI: 10.1111/jvh.13672
Morgan JR, Marsh E, Savinkina A, Shilton S, Shadaker S, et al.
J Viral Hepat. 2022 March 12; Online ahead of print; DOI: 10.1111/jvh.13672
Achieving global elimination of hepatitis C virus requires a substantial scale-up of testing. Point-of-care HCV viral load assays are available as an alternative to laboratory-based assays to promote access in hard to reach or marginalized populations. The diagnostic performance and lower limit of detection are important attributes of these new assays for both diagnosis and test of cure. Therefore, our objective was to determine an acceptable LLoD for detectable HCV viraemia as a test for cure, 12-weeks post-treatment (SVR12). We assembled a global dataset of patients with detectable viraemia at SVR12 from observational databases from 9 countries (Egypt, the United States, United Kingdom, Georgia, Ukraine, Myanmar, Cambodia, Pakistan, Mozambique), and two pharmaceutical-sponsored clinical trial registries. We examined the distribution of HCV viral load at SVR12 and presented the 90th , 95th, 97th, and 99th percentiles. We used logistic regression to assess characteristics associated with low-level virological treatment failure (defined as <1000 IU/mL). There were 5,973 cases of detectable viremia at SVR12 from the combined dataset. Median detectable HCV RNA at SVR12 was 287,986 IU/mL. The level of detection for the 95th percentile was 227 IU/mL (95% CI 170-276). Females and those with minimal fibrosis were more likely to experience low-level viremia at SVR12 compared to men (adjusted odds ratio AOR = 1.60 95% confidence interval [CI] 1.30-1.97 and those with cirrhosis (AOR=1.49 95% CI 1.15-1.93). In conclusion, an assay with a level of detection of 1000 IU/mL or greater may miss a proportion of those with low-level treatment failure
Journal Article > Meta-AnalysisFull Text
J Hepatol. 2019 July 1; Volume 71 (Issue 1); DOI:10.1016/j.jhep.2019.02.011
Freiman JM, Wang J, Easterbrook PJ, Horsburgh CR, Marinucci F, et al.
J Hepatol. 2019 July 1; Volume 71 (Issue 1); DOI:10.1016/j.jhep.2019.02.011
Journal Article > ResearchFull Text
J Viral Hepat. 2022 March 30; Volume 29 (Issue 6); 474-486.; DOI:10.1111/jvh.13672
Morgan JR, Marsh E, Savinkina A, Shilton S, Shadaker S, et al.
J Viral Hepat. 2022 March 30; Volume 29 (Issue 6); 474-486.; DOI:10.1111/jvh.13672
Achieving global elimination of hepatitis C virus requires a substantial scale-up of testing. Point-of-care HCV viral load assays are available as an alternative to laboratory-based assays to promote access in hard to reach or marginalized populations. The diagnostic performance and lower limit of detection are important attributes of these new assays for both diagnosis and test of cure. Therefore, our objective was to determine an acceptable LLoD for detectable HCV viraemia as a test for cure, 12 weeks post-treatment (SVR12). We assembled a global data set of patients with detectable viraemia at SVR12 from observational databases from 9 countries (Egypt, the United States, United Kingdom, Georgia, Ukraine, Myanmar, Cambodia, Pakistan, Mozambique) and two pharmaceutical-sponsored clinical trial registries. We examined the distribution of HCV viral load at SVR12 and presented the 90th, 95th, 97th and 99th percentiles. We used logistic regression to assess characteristics associated with low-level virological treatment failure (defined as <1000 IU/mL). There were 5973 cases of detectable viraemia at SVR12 from the combined data set. Median detectable HCV RNA at SVR12 was 287,986 IU/mL. The level of detection for the 95th percentile was 227 IU/mL (95% CI 170-276). Females and those with minimal fibrosis were more likely to experience low-level viraemia at SVR12 compared to men (adjusted odds ratio AOR = 1.60 95% confidence interval [CI] 1.30-1.97 and those with cirrhosis (AOR = 1.49 95% CI 1.15-1.93). In conclusion, an assay with a level of detection of 1000 IU/mL or greater may miss a proportion of those with low-level treatment failure.