Leland J. Yee

Efficacy of tenofovir disoproxil fumarate at 240 weeks in patients with chronic hepatitis B with high baseline viral load

We evaluated the antiviral response of patients with chronic hepatitis B (CHB) who had baseline high viral load (HVL), defined as having hepatitis B virus (HBV) DNA ≥9 log10 copies/mL, after 240 weeks of tenofovir disoproxil fumarate (TDF) treatment. A total of 641 hepatitis B e antigen (HBeAg)‐negative and HBeAg‐positive patients (129 with HVL) received 48 weeks of TDF 300 mg (HVL n = 82) or adefovir dipivoxil (ADV) 10 mg (HVL n = 47), followed by open‐label TDF for an additional 192 weeks. Patients with confirmed HBV DNA ≥400 copies/mL on or after week 72 had the option of adding emtricitabine (FTC). By week 240, 98.3% of HVL and 99.2% of non‐HVL patients on treatment achieved HBV DNA <400 copies/mL. Both groups had similar rates of histologic regression between baseline and week 240. Patients with HVL generally took longer to achieve HBV DNA <400 copies/mL than non‐HVL patients, but by week 96, the percentages of patients with HBV DNA <400 copies/mL were similar in both groups. Among HVL patients, time to achieving HBV DNA <400 copies/mL was shorter among those initially receiving TDF, compared to ADV. No patient with baseline HVL had persistent viremia at week 240 or amino acid substitutions associated with TDF resistance. Conclusion: CHB patients with HVL can achieve HBV DNA negativity with long‐term TDF treatment, although time to HBV DNA <400 copies/mL may be longer, relative to patients with non‐HVL. (Hepatology 2013;58:505–513)

Evaluation of APRI and FIB-4 scoring systems for non-invasive assessment of hepatic fibrosis in chronic hepatitis B patients

BACKGROUND & AIMS While the gold standard in the assessment of liver fibrosis remains liver biopsy, non-invasive methods have been increasingly used for chronic hepatitis B (CHB). This study aimed to evaluate the performance of two commonly used non-invasive scoring systems (aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on four factors (FIB-4)) to predict fibrosis stage in CHB patients. METHODS Demographic, histologic and clinical laboratory data from two trials investigating tenofovir disoproxil fumarate in CHB were analyzed. Predicted fibrosis stage, based on established scales and cut-off values for APRI and FIB-4 scores, was compared with Ishak scores obtained from liver biopsy at baseline and at 240 week follow-up. RESULTS In the 575 patients with a baseline liver biopsy, APRI and FIB-4 scores correlated with Ishak stage (p<0.01); however extensive overlap in the distribution of both scores across Ishak stages prevented accurate determination of fibrosis. The majority (81-89%) of patients with advanced fibrosis or cirrhosis were missed by the scores. Similarly, 71% patients without fibrosis were misclassified as having clinically significant fibrosis. APRI and FIB-4 scores at week 240 tended to be low and underestimate fibrosis stage in the patients with liver biopsies after 240 weeks of therapy. APRI or FIB-4 reduction did not correlate with fibrosis regression after 240 weeks of antiviral therapy. CONCLUSIONS APRI and FIB-4 scores are not suitable for use in clinical practice in CHB patients for assessment of hepatic fibrosis according to Ishak stage, especially in gauging improvements in liver fibrosis following therapy.

Associations between serum lipids and hepatitis C antiviral treatment efficacy

Approximately one half of patients who undergo antiviral therapy for chronic hepatitis C virus (HCV) genotype 1 infection do not respond to treatment. African Americans (AAs) are less responsive to treatment than Caucasian Americans (CAs), but the reasons for this disparity are largely unknown. Recent studies suggest that serum lipids may be associated with treatment response. The aims of this study were to evaluate baseline and changes in serum lipids during therapy, determine whether serum lipids are associated with virological response, and assess whether these measures explain the racial difference in efficacy. The study participants were from Virahep‐C, a prospective study of treatment‐naïve patients with genotype 1 HCV infection who received peginterferon (PEG‐IN) alfa‐2a plus ribavirin therapy for up to 48 weeks. Fasting serum lipids were analyzed at baseline and during and after therapy in 160 AAs and 170 CAs. A relative risk (RR) model was employed to evaluate characteristics associated with sustained virological response (SVR). Antiviral therapy was associated with changes in serum lipids during and after antiviral therapy, with the changes differing by race and the amount of PEG‐IFN taken. Baseline lipid measures independently associated with higher rates of SVR were lower triglyceride and higher low‐density lipoprotein cholesterol, with an interaction between high‐density lipoprotein cholesterol (HDLc) and gender. Lipid measures did not contribute significantly to an explanation of the racial difference in SVR. Conclusion: Serum lipids are associated with SVR, although these paramaters did not explain the racial difference in treatment response. The results of this study are compatible with proposed biological mechanisms of HCV entry, replication, and secretion, and may underscore new potential therapeutic targets for HCV eradication. (Hepatology 2010)

A community-based rapid assessment of HIV behavioural risk disparities within a large sample of gay men in southeastern USA: A comparison of African American, Latino and white men

Abstract Because the southeastern USA is experiencing a disproportionate HIV infection rate compared to other regions of the country, we explored HIV behavioural risk disparities by race/ethnicity among self-identifying gay men. Conceived and implemented as a community-based participatory research (CBPR) study, this rapid assessment collected demographic and HIV risk-behaviour data from men in five gay bars in the northwestern part of the state of North Carolina, using an assessment available in English and Spanish. Of 719 participants, 34.8% reported inconsistent condom use during anal intercourse in the past three months, 11.4% reported ever having had a sexually transmitted disease (STD), 3.6% reported being HIV-seropositive and 26% reported illicit drug use during the past 30 days. Compared to white participants, African American/black and Hispanic/Latino participants were more likely to report inconsistent condom use during anal intercourse with multiple partners during the past three months. African American/black participants were more likely to report illicit drug use during the past 30 days. Hispanic/Latino participants were more likely to have never been tested for HIV. Rates of HIV risk behaviours among gay men remain high and racial/ethnic differences indicate the need for targeted and tailored prevention strategies.

Impact of long‐term tenofovir disoproxil fumarate on incidence of hepatocellular carcinoma in patients with chronic hepatitis B

Efficacy trials have shown that antiviral therapy improves the outcomes of patients with chronic hepatitis B virus (HBV) infection. However, prospective data regarding the effect of antiviral therapy on the incidence of hepatocellular carcinoma (HCC), especially among patients without cirrhosis, are limited. The authors examined the impact of tenofovir disoproxil fumarate (TDF) on the incidence of HCC using a validated prediction model.

Association of single nucleotide polymorphisms in interferon signaling pathway genes and interferon-stimulated genes with the response to interferon therapy for chronic hepatitis C

BACKGROUND/AIMS Interferon signaling pathway genes (IPGs) and interferon-stimulated genes (ISGs) are associated with the host response to hepatitis C virus (HCV) infection. We studied single nucleotide polymorphisms (SNPs) in IPGs and ISGs for their associations with response to pegylated interferon alpha-2a (Peg-IFN-alpha) plus ribavirin therapy in HCV genotype-1 infected patients. METHODS A two-stage study design was used. First, out of 118 SNPs selected, 91 SNPs from 5 IPGs and 12 ISGs were genotyped in a cohort of 374 treatment-naïve HCV patients and assessed for association with sustained virologic response (SVR). Next, 14 potentially functional SNPs from the OASL gene were studied in this cohort. RESULTS Three OASL SNPs (rs3213545 and rs1169279 from stage I, and rs2859398 from stage II), were significantly associated with SVR [rs3213545: p=0.03, RR=1.27 (1.03-1.58); rs1169279: p=0.02, RR=1.32 (1.05-1.65) p=0.02; rs2859398: p=0.02, RR=1.29 (1.04-1.61)] after adjusting for other covariates. Further analysis showed that these three SNPs independently associated with SVR. Additionally, a similar trend towards the associations of these three SNPs with SVR was observed in a smaller, independent HCV cohort consisting of subjects from a number of clinical practice settings. CONCLUSIONS Our study suggests that OASL variants are involved in the host response to IFN-based therapy in HCV patients.

Using Community-Based Participatory Research to Develop a Chat Room-Based HIV Prevention Intervention for Gay Men

Background: Although seeking sexual partners on the Internet is an identified risk factor for HIV and sexually transmitted disease infection among gay men and men who have sex with men (MSM), the medical literature lacks descriptions of the development, implementation, and evaluation of interventions for reducing infections among men who seek sexual partners online. Objectives: We sought to fill this gap by describing Cyber-Based Education and Referral/Men for Men (CyBER/M4M), an intervention designed to reduce HIV exposure and transmission among gay men and MSM who use geographically defined chat rooms. Methods: CyBER/M4M was developed by a community–university partnership that included gay men who had experience with seeking sexual partners online, and representatives from community-based organizations, the local Results: Two products emerged: the CyBER/M4M Training Manual, designed to facilitate training of lay health advisors known as CyBER/M4M Educators, and CyBER/M4M Resource Manual, designed as a reference for the Educators. Conclusions: Further research is clearly needed, but this work provides insight into the development, implementation, and evaluation of a chat room-based HIV prevention intervention using CBPR.

Interleukin-6 haplotypes and the response to therapy of chronic hepatitis C virus infection.

Chronic hepatitis C virus (HCV) infection affects nearly 170 million individuals worldwide. Treatment of HCV with pegylated interferon-α-2a is successful in eradicating virus from only 30 to 80% of those treated. Interleukin-6 (IL-6) is an important cytokine involved in the immune response to infectious agents and in vitro studies suggest that host genetic variation, particularly haplotypes, may affect IL-6 expression. We examined the contribution of haplotypes in the IL-6 gene on sustained viral response (SVR) to the therapy for chronic HCV infection. We observed the IL-6 T-T-G-G-G-G-C-A-G-A haplotype to be associated with a lower risk of achieving SVR among Caucasian Americans (CAs) ((relative risk) RR=0.80; 95% CI: 0.66−0.98; P=0.0261). Using a sliding window approach, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was associated with a reduced chance of SVR (RR=0.79; 95% CI: 0.66–0.94; P=0.0081), as was the rs1800796-(G)-rs1800795-(G)-rs2069830-(C) haplotype (RR=0.78; 95% CI: 0.66–0.94; P=0.0065) among CAs. Overall, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was independently associated with a reduced chance of SVR (RR=0.78; 95% CI: 0.62–1.0; P=0.0489) after adjustment for potential confounding factors. Our findings further illustrate the complexity of IL-6 genetic regulation and the potential importance of haplotypes on IL-6 expression. Our findings provide additional support for the potential importance of genetic variation in the IL-6 gene and the response to HCV therapy.

Associations between the human MHC and sustained virologic response in the treatment of chronic hepatitis C virus infection

The human major histocompatability complex (MHC) genes encode the human leukocyte antigens, which are important in antigen presentation and regulation of CD8+ and CD4+ T cells. Response to therapies in hepatitis C virus (HCV) infection is highly variable (30–80%) and lower response rates have been reported among African Americans (AA; ∼30%) compared to Caucasian Americans (CA; ∼50%) infected with genotype-1 viruses. We evaluated whether MHC gene variants were associated with response to therapy and racial differences in AA and CA sustained virologic response (SVR) rates. We genotyped alleles at 8 MHC loci: 3 class I (A, B and C) and 5 class II (DRB1, DQA1, DQB1, DPA1 and DPB1) loci in 373 individuals (179 AA and 194 CA) with genotype-1 HCV infections, who were treated with peginterferon-α-2a and ribavirin. We observed carriage of A*02 (RR=1.33(1.08–1.64); P=0.008), B*58 (RR=1.84(1.24-2.73); P=0.002) and DPB1*1701 (RR=1.57(1.09-2.26); P=0.015) to be associated with SVR after adjustment for other predictors of response. In analysis of AA and CA subgroups separately, we observed potential, though not statistically significant, differences in these MHC associations. Variation in the immunogenetic background of HCV-infected individuals might account for some observed variation in viral-specific immunity and courses of disease. In this regard, future studies examining broader patient populations are warranted.

Serum lipids and their associations with viral levels and liver disease severity in a treatment‐naïve chronic hepatitis C type 1‐infected cohort

Summary.  In patients with chronic hepatitis C virus (HCV) infection, steatosis and fibrosis have been shown to be inversely associated with total cholesterol (TC) and low‐density lipoprotein cholesterol. Steatosis and fibrosis have also been found to be associated with triglyceride (TG) levels; though, the direction of the relationship is inconsistent across studies. The objective of this study was to assess whether viral level and histological factors are associated with the serum lipid profile in a treatment‐naïve cohort with chronic HCV genotype 1 infection. Participants were from the prospective Study of Viral Resistance to Antiviral Therapy (Virahep‐C). Fasting lipid profiles were analysed for 160 African Americans and 170 Caucasian Americans. Linear regression was used to evaluate associations of each lipid with viral load and liver disease. TG levels were significantly and directly associated with HCV levels (P = 0.0034) and steatosis (P < 0.0001). Other lipid parameters were significantly lower in those with fibrosis [HDLc (P = 0.001) and TC levels (P = 0.004)] than in those without fibrosis. In patients with HCV genotype 1 infection, more severe liver disease was associated with lower lipid levels, with the exception of TG levels that were directly related to steatosis. The direct relationship between viral load and TG levels is consistent with proposed the mechanisms of very low density lipoprotein/HCV particle secretion. In contrast, the direct relationship between TG level and steatosis is inconsistent with posited mechanisms of HCV‐induced steatosis, a possible reflection of HCV genotype 1 infection and a metabolic aetiology of steatosis.