Long-term Outcomes of Anti-viral Therapies in Patients With Chronic Viral Hepatitis B (OASIS)

Fudan University

Status: Enrolling

Conditions: Chronic Hepatitis b

Treatments: Drug: nucleos(t)ide; Drug: peginterferon alpha based regimen

Study type: Observational

Funder types: Other

Identifiers

NCT04896255

KY2020-911

Details and patient eligibility

About

The goal of this observational, multicenter , real-world study is to evaluate the long-term outcomes of different antiviral therapies in adults with chronic hepatitis B (CHB). The main questions it aims to answer are: What is the 5-year incidence of hepatocellular carcinoma (HCC) under various treatment regimens? How do rates of HBsAg seroclearance, decompensated cirrhosis, liver fibrosis progression, and other virological and clinical outcomes compare across regimens? Researchers will compare real-world treatment arms-including nucleos(t)ide analogue (NA) monotherapy (e.g., entecavir, tenofovir), PegIFN based regimen (e.g., PegIFN monotherapy, PegIFN plus NA combinations)-to identify optimal strategies for reducing HCC risk and improving functional cure rates.

Participants will undergo routine clinical care with no study-imposed interventions; data on demographics, medical history, symptoms, laboratory tests (e.g., HBsAg, HBV DNA, liver function), imaging (e.g., ultrasound, elastography), and clinical events will be collected prospectively (for up to 5 years in some cohorts) or retrospectively from medical records at baseline and scheduled follow-up visits (e.g., every 3-12 months initially, then annually).

Full description

The OASIS study is a multicenter, observational, real-world cohort study designed to evaluate long-term outcomes of antiviral therapies for chronic hepatitis B (CHB). It compares nucleos(t)ide analogue (NA) monotherapy, pegylated interferon based regimen without randomization or blinding. Treatment decisions follow routine clinical guidelines, physician expertise, and patient-specific factors. The study includes three cohorts: Prospective (PS, 5-year follow-up post-consent), Retrospective-Prospective (RPS, retrospective from baseline ≥September 2020 to consent, then 5-year prospective), and Retrospective (RS, data from September 2020 to protocol implementation). The target of 33,000 patients was determined based on patient flow across sub-centers, ensuring sufficient power to detect differences in 5-year HCC incidence (primary endpoint) and secondary outcomes (e.g., HBsAg seroclearance rates).

Enrollment: 33,000 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Male and female patients with age ≥18; subjects who are over 70 years of age must be in generally stable health conditions.
• There should be evidences that HBsAg has been positive for more than 6 months or HBV-related histological changes.
• Planned or currently receiving potent low-resistance NAs [entecavir (ETV), tenofovir disoproxil fumarate (TDF), tenofovir alafenamide fumarate (TAF), or tenofovir amibufenamide (TMF)], or planned to receive PegIFNα-2b, either treated or treatment-naïve.
• Agree to participate in the study and sign the patient informed consent form.

Exclusion criteria

• Hepatocellular carcinoma (diagnosed or planned for treatment) or liver failure at baseline
• Concurrently participating in other interventional clinical trials.
• Any other conditions deemed unsuitable by investigators or preventing compliance with study requirements.

Trial design

33,000 participants in 3 patient groups

Prospective

Description:

CHB patients enrolled pre-Protocol v3.0 (Dec 2023), planned or on antiviral therapy, followed prospectively for 5 years post-consent. Treatments: routine NA monotherapy, or PegIFN based regimens, per clinical guidelines. Data: baseline and 5 -year follow-up via routine visits.

Treatment:

Drug: peginterferon alpha based regimen

Drug: nucleos(t)ide

Retrospective-Prospective

Description:

CHB patients with baseline (≥Sep 2020) pre-v3.0, consenting post-v3.0. Retrospective data from baseline to consent; prospective for 5 years from baseline. Treatments: NAs monotherapy, or PegIFN based regimens. Data: retrospective before consent; prospective from visit matching baseline-consent interval. Missing routine data noted.

Treatment:

Drug: peginterferon alpha based regimen

Drug: nucleos(t)ide

Retrospective

Description:

CHB patients with records from Sep 2020 to v3.0 (Dec 2023), collected retrospectively. Treatments: NAs monotherapy, or PegIFN based regimens, per historical practice. Data: extracted from the electronic healthcare record; missing routine data recorded.

Treatment:

Drug: peginterferon alpha based regimen

Drug: nucleos(t)ide