Time to seroconversion of HBsAg to anti-HBs in individuals who lost HBsAg during follow-up

Hepatitis B Surface Antigen Levels Are Related to Spontaneous Hepatitis B Surface Antigen Seroconversion in Inactive Hepatitis B Carriers

BACKGROUND

The cure for hepatitis B is defined as the hepatitis B surface antigen (HBsAg) seroclearance and/or seroconversion. Predictors of spontaneous seroconversion are not well described. The objective of this study is to identify predictors of spontaneous HBsAg seroconversion from community practice.

METHODS

We performed a matched analysis of patients who HBsAg seroconverted (cases) and patients who did not HBsAg seroconvert (control) in a 1:5 ratio according to date of clinic visit between 2014 and 2019 in a large community practice situated in Los Angeles area. Baseline laboratory and clinical data were collected. Univariate analysis and 2-sided t tests were performed, χ test for proportions, and logistic regression.

RESULTS

We identified 14 cases and 70 controls. The mean (±SD) ages of the cases and controls were 53.6 (±12.2) and 49.5 (±13.1), respectively (P=0.45). Most patients were women, and all patients were of Asian descent. There were statistically significant mean (±SD) baseline differences between cases and controls in HBsAg titers (459.8±311.0 and 782.0±393.3 IU/mL, P=0.01) and alanine aminotransferase (ALT) values (17.6±4.4 and 25.1±16.7 IU/mL, P<0.01), respectively. Baseline hepatitis B virus DNA and other pertinent laboratory values did not differ between cases and controls. Eleven of 14 cases (79%) and 11 of 70 controls (16%) baseline HBsAg titers were <1000 IU/mL (P<0.01). The results of a logistic regression demonstrated that HBsAg titers and ALT values were predictor variables for HBsAg seroconversion (P=0.01 and <0.01, respectively).

CONCLUSIONS

Spontaneous HBsAg seroclearance and seroconversion is an uncommon event in patients with chronic hepatitis B. The most important predictors of seroconversion are HBsAg titers<1000 IU/mL and low baseline ALT values.

Durability of Hepatitis B Surface Antigen Loss With Nucleotide Analogue and Peginterferon Therapy in Patients With Chronic Hepatitis B

In patients with chronic hepatitis B (CHB), loss of hepatitis B surface antigen (HBsAg) is considered a functional cure. However, HBsAg loss is uncommon with existing therapies, and predictive factors associated with HBsAg seroreversion are unknown. Using pooled data from three phase 3 clinical trials of patients with CHB treated with nucleos(t)ide analogue (NUC) monotherapy or peginterferon (Peg‐IFN) ± NUC combination therapy, we conducted a retrospective analysis to characterize patients who achieved sustained HBsAg loss, the predictors of HBsAg seroreversion, and the impact of hepatitis B surface antibody (anti‐HBs) seroconversion on durability of HBsAg loss. In these three international trials, 1,381 adults with CHB received either NUC monotherapy for up to 10 years or Peg‐IFN‐containing regimens for up to 1 year. A total of 55 patients had confirmed HBsAg loss, defined as two or more consecutive negative‐qualitative HBsAg results, with a minimum of one repeat result after the end of treatment. Throughout a median of 96 (quartile [Q]1, Q3, 46, 135) weeks follow‐up after HBsAg loss, HBsAg loss was durable in 82% (n = 45) of patients, with 10 patients experiencing HBsAg seroreversion. Anti‐HBs seroconversion was observed during follow‐up in 78% of patients who lost HBsAg and in 60% of those who subsequently seroreverted. In analyzing predictors of HBsAg seroreversion, study treatment was significant, yet anti‐HBs seroconversion and treatment duration after initial HBsAg loss were not. Risk of HBsAg seroreversion was observed to be lower if HBsAg loss was sustained through the off‐treatment week 24 visit (8/10 seroreversions occurred by posttreatment week 24). Conclusion: HBsAg loss after NUC or Peg‐IFN‐containing regimens was durable in 82% of patients with CHB. Anti‐HBs seroconversion and treatment duration after initial HBsAg loss were not significantly associated with durability of HBsAg loss.

Understanding the patient population and test utilization for hepatitis B virus testing

BACKGROUND

Hepatitis B virus (HBV) infection remains a global concern with different epidemiologies due to several factors including migration, vaccination policies, and new antiviral treatment regimens. It is important to understand the characteristics of a patient population, including the prevalence of diseases, and to assess test utilization to understand and evaluate the clinical performance of laboratory tests and to improve the quality of clinical laboratories.

MATERIALS AND METHODS

In this study, we evaluated serologic and virologic laboratory tests including hepatitis B surface antigen, hepatitis B surface antibody, hepatitis B envelope antigen (HBeAg), hepatitis B envelope antibody, and HBV DNA in Korean adults who were exposed to HBV.

RESULTS

During the 1-year study period, we obtained 22 750 specimens from 17 523 adult Korean patients (>18.0 years; 9894 males and 7629 females) with a median age of 50.1 years (interquartile range, 42.2-58.2 years). Among them, five serologic and virologic laboratory tests were performed for 1340 (5.9%) specimens from 1172 adult Korean patients (>18.0 years; 647 males and 525 females) with a median age of 46.8 years (range, 19.0-84.5 years). The prevalence of serologic and virologic tests indicating several clinical situations was evaluated. The correlation coefficient between HBV DNA and HBeAg was ρ = 0.85 (P < .0001). However, 51.9% (695/1340) of samples did not show agreement between the two test results.

CONCLUSIONS

Analysis of the prevalence of patients categorized into five serologic and virologic laboratory results would be helpful to expand our knowledge about patient population characteristics and to improve test utilization.

Incidence and determinants of spontaneous hepatitis B surface antigen seroclearance and seroconversion in hepatitis B e antigen-negative chronic infection patients: A population-based prospective cohort

Seroclearance of hepatitis B surface antigen (HBsAg) has been widely studied; however, seroconversion of HBsAg and characteristics of viral load among hepatitis B e antigen (HBeAg)-negative chronic infection patients after HBsAg lost is not clear. We performed a large-scale study in a HBeAg-negative chronic infection cohort to evaluate spontaneous HBsAg seroclearance incidence from October 2012 to April 2017 in Jiangsu province, China. We also elucidated the characteristics of HBsAg seroconversion and hepatitis B virus (HBV) DNA detectability among patients who cleared HBsAg. A total of 2997 HBeAg-negative chronic infection patients (mean age 52.3 ± 12.9 years at baseline) were included. With 10 519 person-years of follow-up, 348 patients successfully spontaneously cleared HBsAg, with an incidence rate of 3.31 per 100 person-years. Patients with HBV DNA detectable ~1999 IU/mL at baseline had a lower probability of HBsAg seroclearance relative to those with undetectable HBV DNA, with a hazard ratio of 0.31 (95% CI = 0.23, 0.41). HBsAg seroconversion occurred in 37.3% of those patients who cleared HBsAg. The geometric mean of anti-HBs among those with HBsAg conversion was 79.4 mIU/mL. Female had a higher HBsAg seroconversion rate (P = 0.011). Among those with HBsAg seroclearance, 11.2% still had HBV DNA levels of higher than 100 IU/mL. Patients with higher HBV DNA at baseline had a higher risk of detectable HBV DNA levels even after HBsAg seroclearance (P < 0.001). This study reveals HBsAg seroconversion rates and HBV DNA undetectability epidemiological characteristics of patients with HBsAg seroclearance and suggests that monitoring HBV DNA is needed when managing HBeAg-negative chronic patients, even after clearing HBsAg.

Use of ELISpot assay to study HBs-specific B cell responses in vaccinated and HBV infected humans

Hepatitis B surface antibody (HBsAb) plays a critical role in protecting against infection of hepatitis B virus (HBV) and were extensively studied in literature. At the same time, the status of hepatitis B surface antigen (HBs)-specific B cells in both vaccinated and HBV infected people received limited attention. In the current study, we adopted a highly specific B-cell Enzyme Linked ImmunoSpot (ELISpot) assay to analyze HBs-specific B cells in various clinical settings: healthy individuals with the history of HBV vaccination before and after receiving an extra HBV vaccine boost, people chronically infected with HBV (CHB) in various clinical stages, with or without a particular type anti-viral treatment, or whether receiving a dose of HBV vaccine. In all of these cases, B-cell ELISpot assay was used effectively in enumerating the frequency of HBs-specific B cells. While the focus of the current report was to establish the utility of this assay for HBV research, a number of interesting observations were made in this pilot study based on the profiles and dynamics of HBs-specific B cells in various conditions. Such information is useful to guide the future work in designing novel therapeutic strategies against CHB.