Risk of hepatocellular carcinoma in treatment-naïve chronic hepatitis B patients receiving tenofovir disoproxil fumarate versus entecavir in the United States

BACKGROUND

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are the first-line treatment agents for chronic hepatitis B virus (HBV). Recently, whether the degree to which the risk of hepatocellular carcinoma (HCC) may be reduced by ETV vs TDF has been debated. We compared the incidence of HCC among treatment-naïve patients receiving TDF vs ETV in the United States.

METHODS

From a large administrative medical claims database of commercially insured patients, we identified 166,933 adults with a diagnosis of chronic hepatitis B and a minimum of 12 months of prior enrolment, of whom 3934 and 6127 initiated ETV and TDF respectively. Fine-Gray hazard regression models incorporating treatment propensity scores (PS) were used to estimate the risk of HCC incidence associated with TDF vs ETV; variables considered for adjustment included demographic characteristics, concomitant medication use and baseline comorbidities, as well as competing events including liver transplantation and medication changes.

RESULTS

After PS weighting, the TDF and ETV groups were well-matched. During the follow-up, 90 patients developed HCC, including 50 receiving ETV and 40 receiving TDF, giving rise to crude incidence rates of 0.62 per 100 person-years (PY) and 0.30 per 100 PY respectively. In PS-weighted, multivariable analysis, TDF was associated with a subdistribution hazard ratio for HCC of 0.58 (95% confidence interval [CI]: 0.38-0.89) compared to ETV. Results were similar when patients ≥40 years and men and women were analysed separately.

CONCLUSION

Among commercially insured, treatment-naïve patients with chronic hepatitis B in the United States, treatment with TDF was associated with significantly lower risk of HCC than ETV.

Treatment with tenofovir disoproxil fumarate or entecavir in chronic hepatitis B virus-infected patients with renal impairment: results from a 7-year, multicentre retrospective cohort study

BACKGROUND

Limited data exist regarding tenofovir disoproxil fumarate (TDF) safety and effectiveness in chronic hepatitis B virus-infected (CHB) patients with renal impairment (RI).

AIMS

To compare real-world data on renal safety and effectiveness of TDF vs entecavir (ETV) in CHB patients with moderate-to-severe RI.

METHODS

Retrospective, non-interventional, cohort study analysing medical records for TDF/ETV-treated CHB patients (54 European centres). Included patients experienced moderate-to-severe RI (creatinine clearance 20-60 mL/min [Cockcroft-Gault]) either before TDF/ETV initiation ('before' subgroup [baseline = treatment initiation]) or after TDF/ETV initiation ('after' subgroup [baseline = first RI occurrence]). The primary objective was TDF safety, particularly renal-related adverse events of special interest (AESI). TDF and ETV safety and effectiveness were compared and multivariate analyses were performed using inverse probability treatment weighting.

RESULTS

'Before' subgroup included 107 TDF- and 91 ETV-treated patients; 'after' subgroup included 212 TDF- and 77 ETV-treated patients. Mean baseline creatinine clearance was higher for TDF- vs ETV-treated patients (both subgroups). Median follow-up was 3.1 years (both treatments). AESI were more frequent with TDF vs ETV ('before': 18.7% vs 8.8%; 'after': 9.9% vs 3.9%); however, differences were not significant by multivariate analysis. Only TDF-treated patients experienced renal tubular dysfunction (6.5% 'before'; 1.9% 'after') as well as renal adverse events leading to treatment discontinuation (8.4% 'before'; 7.1% 'after'). Effectiveness was similar between treatments.

CONCLUSIONS

Overall safety was similar for TDF vs ETV (both subgroups). Given that renal tubular dysfunction occurred with TDF and not with ETV, renal safety concerns may be greater with TDF in CHB patients with RI.

Ten-year efficacy and safety of tenofovir disoproxil fumarate treatment for chronic hepatitis B virus infection

BACKGROUND & AIMS

Tenofovir disoproxil fumarate (TDF) is a first-line treatment for chronic hepatitis B (CHB). We aimed to describe the efficacy and safety profiles of TDF treatment for up to 10 years in a well-described cohort of CHB patients.

METHODS

Hepatitis B e antigen (HBeAg)-negative and HBeAg-positive patients from two randomised, double-blind trials (ClinicalTrials.gov: NCT00117676 and NCT00116805) completed 48 weeks of randomised treatment with TDF or adefovir dipivoxil. A subset of these patients was then eligible to receive open-label TDF treatment for up to 10 years. At Year 10, patients were assessed for virological suppression, alanine aminotransferase (ALT) normalisation, serological response, safety and tolerability.

RESULTS

Of 641 randomised and treated patients, 585 (91%) entered the open-label extension phase with 203 (32%) patients completing Year 10 of the study. At Year 10, 118/118 (100%) of HBeAg-negative patients and 78/80 (98%) of HBeAg-positive patients with available data achieved hepatitis B virus (HBV) DNA < 69 IU/mL, while 88/106 (83%) and 60/77 (78%) patients achieved ALT normalisation, respectively. Of the 23 patients with HBeAg status available at Year 10, 12 (52%) and six (27%) experienced HBeAg loss and seroconversion, respectively. No resistance to TDF was documented up to Year 10. In the period between Year 8 and Year 10, the safety profile of TDF was similar to previous reports, with few patients experiencing renal- or bone-related adverse events.

CONCLUSIONS

Over 10 years, TDF had a favourable safety profile, was well tolerated, and resulted in continued maintenance of virological suppression with no documented resistance.

Hepatitis B Surface Antigen Loss with Tenofovir Disoproxil Fumarate Plus Peginterferon Alfa-2a: Week 120 Analysis

BACKGROUND AND AIMS

Hepatitis B surface antigen (HBsAg) loss is the ideal clinical endpoint but is achieved rarely during oral antiviral treatment. A current unmet need in CHB management is achievement of HBsAg loss with a finite course of oral antiviral therapy, thereby allowing discontinuation of treatment. Significantly higher rates of HBsAg loss at 72 weeks post-treatment have been demonstrated when tenofovir disoproxil fumarate (TDF) was combined with pegylated interferon (PEG-IFN) for 48 weeks compared with either monotherapy. This analysis provides follow-up data at week 120.

METHODS

In an open-label, active-controlled study, 740 patients with chronic hepatitis B were randomly assigned to receive TDF plus PEG-IFN for 48 weeks (group A), TDF plus PEG-IFN for 16 weeks followed by TDF for 32 weeks (group B), TDF for 120 weeks (group C), or PEG-IFN for 48 weeks (group D). Efficacy and safety at week 120 were assessed.

RESULTS

Rates of HBsAg loss at week 120 were significantly higher in group A (10.4%) than in group B (3.5%), group C (0%), and group D (3.5%). Rates of HBsAg loss and HBsAg seroconversion in group A were significantly higher than rates in group C (P < 0.001 for both) or group D (HBsAg loss: P = 0.002; HBsAg seroconversion: P < 0.001).

CONCLUSIONS

The results of this analysis confirm the results from earlier time points which demonstrate the increased rate of HBsAg loss in patients treated with a finite course of PEG-IFN plus TDF compared with the rates in patients receiving either monotherapy.

Long-term response after stopping tenofovir disoproxil fumarate in non-cirrhotic HBeAg-negative patients - FINITE study

BACKGROUND & AIMS

There is currently no virological cure for chronic hepatitis B but successful nucleos(t)ide analogue (NA) therapy can suppress hepatitis B virus (HBV) DNA replication and, in some cases, result in HBsAg loss. Stopping NA therapy often leads to viral relapse and therefore life-long therapy is usually required. This study investigated the potential to discontinue tenofovir disoproxil fumarate (TDF) therapy in HBeAg-negative patients.

METHODS

Non-cirrhotic HBeAg-negative patients who had received TDF for ≥4years, with suppressed HBV DNA for ≥3.5years, were randomly assigned to either stop (n=21) or continue (n=21) TDF monotherapy. Standard laboratory tests including HBV DNA viral load, HBsAg and alanine aminotransferase (ALT) measurements, and adverse event reporting were carried out during treatment and post-treatment follow-up for 144weeks.

RESULTS

Of the patients who stopped TDF therapy, 62% (n=13) remained off-therapy to Week 144. Median HBsAg change in this group was -0.59log₁₀IU/ml (range -4.49 to 0.02log₁₀IU/ml) vs. 0.21log₁₀IU/ml in patients who continued TDF therapy. Four patients (19%) achieved HBsAg loss. Patients stopping therapy had initial fluctuations in viral load and ALT; however, at Week 144, 43% (n=9) had either achieved HBsAg loss or had HBV DNA <2,000IU/ml. There were no unexpected safety issues identified with stopping TDF therapy.

CONCLUSIONS

This controlled study demonstrated the potential for HBsAg loss and/or sustained virological response in non-cirrhotic HBeAg-negative patients stopping long-term TDF therapy. Lay summary: Nucleos(t)ide analogue (NA) is usually a life-long therapy for HBV patients. This randomised controlled study investigated the discontinuation of tenofovir disoproxil fumarate (TDF) therapy in HBeAg-negative patients. Of the patients who stopped TDF therapy, 62% remained off-therapy to Week 144, of which 43% of patients had achieved either HBsAg loss or HBV DNA <2,000IU/ml. This offers a potential for long-term HBV-suppressed patients without cirrhosis to stop NA therapy under strict surveillance. Clinical trial number: NCT01320943.

Production pressure in the work environment. California anesthesiologists' attitudes and experiences

BACKGROUND

Pressure to put efficiency, output, or continued production ahead of safety has caused catastrophic accidents in various industries. The authors assessed the attitudes and experiences of anesthesiologists concerning production pressure.

METHODS

A random, repeated-mailing survey was conducted among 647 members of the American Society of Anesthesiologists residing in California. Questions were asked about attitudes toward production pressure and other patient safety issues, frequency of occurrence of various operating room events, encounters with situations involving unsafe actions, and ratings of sources of production pressure.

RESULTS

Forty-seven percent of those sampled returned surveys. The demographics of the respondent population were largely similar to those of the population of anesthesiologists in California. There was no systematic difference between the respondents to the first versus the second mailing, reducing (but not eliminating) the possibility of self-selection bias. Nearly half (49%) of respondents had witnessed production pressure result in what they believed to be unsafe actions by an anesthesiologist. Such events included elective surgery in patients without adequate evaluation or with significant contraindications to surgery. Anesthesiologists felt pressures within themselves to work agreeably with surgeons, avoid delaying cases, and avoid litigation. They also reported overt pressure by surgeons to proceed with cases instead of cancelling them, and to hasten anesthetic procedures. Some aspects of production pressure were perceived differently by those reimbursed by fee-for-service versus those paid by salary.

CONCLUSIONS

Production pressure from internal and external sources is a reality for many anesthesiologists and is perceived in some cases to have resulted in unsafe actions being performed.