Chronic Hepatitis B Antiviral Therapy (Baraclude, Pegasys, Vemlidy)

Coverage Summary

This policy addresses antiviral therapy for chronic hepatitis B (CHB) with specific coverage criteria for Baraclude (entecavir), Pegasys (peginterferon alfa-2a), and Vemlidy (tenofovir alafenamide). Coverage stance is mixed: each agent has defined medical necessity requirements rather than universal coverage. Age limits are: Baraclude ≥2 years, Pegasys ≥18 years for adults and ≥3 years for non-cirrhotic pediatric HBeAg-positive CHB, and Vemlidy ≥6 years. The policy specifies coinfection considerations (HIV, HCV, HDV) in determining eligibility and sequencing of therapy. Prior-treatment requirements and step therapy are applied for some products (e.g., prior generic entecavir before Baraclude; prior trial of generic tenofovir disoproxil fumarate for Vemlidy when weight ≥35 kg). Initial and re-authorization approvals are for up to 12 months per authorization, with documentation requirements for ongoing clinical response.

Initial Therapy Criteria

Baraclude (entecavir) - Medical Necessity

Baraclude (entecavir) may be considered medically necessary when ALL of the following are met:

ALL of the following

Age: The individual is aged 2 years or older
Diagnosis: Has a confirmed diagnosis of chronic hepatitis B virus (HBV) infection
Age and liver disease status
- Adult: Individuals aged 18 years or older with compensated or decompensated liver disease
- Pediatric: Individuals aged 2 to 17 years with compensated liver disease
Prior treatment: Has had inadequate response or intolerance to generic entecavir
HIV coinfection status
- No HIV: Does not have a co-infection with human immunodeficiency virus (HIV)

Clinical trials and efficacy context: Efficacy demonstrated in adult and pediatric trials with proportions achieving undetectable or low HBV DNA at Week 48

Examples: adult studies showed 67%-90% undetectable HBV DNA (<300 copies/mL); pediatric study showed HBV DNA <50 IU/mL in a substantial proportion

Pegasys (peginterferon alfa-2a) - Medical Necessity (CHB & other)

Pegasys (peginterferon alfa-2a) may be considered medically necessary for the treatment of chronic hepatitis B virus (HBV) infection in the following groups and as specified:

Top-level eligible groups

Adult CHB (compensated) with viral replication and inflammation
- Age: Individuals aged 18 years or older
- Disease features: HBeAg-positive and HBeAg-negative chronic HBV infection who have compensated liver disease and evidence of viral replication and liver inflammation
Pediatric CHB (non-cirrhotic)
- Age: Non-cirrhotic pediatric individuals aged 3 years or older with HBeAg-positive CHB

Vemlidy (tenofovir alafenamide) - Medical Necessity

Vemlidy (tenofovir alafenamide) may be considered medically necessary when ALL of the following are met:

ALL of the following

Age: The individual is aged 6 years or older
Diagnosis: Has a confirmed diagnosis of chronic hepatitis B virus (HBV) infection
Liver status: Has compensated liver disease
HIV coinfection allowance
- No HIV coinfection:

Continuation Therapy & Length of Approval

Length of Approval

Authorization durations per policy:

Initial authorization: up to 12 months

Re-authorization: up to 12 months if medical necessity criteria are met and chart notes show continued positive clinical response (e.g., reduction in HBV DNA levels)

Example evidence: reduction in hepatitis B virus DNA levels

Unproven / Exclusions

Uses Considered Investigational

All other uses not outlined in this policy or policy 5.01.606 are considered investigational.

FDA dosing adherence: Medications listed are subject to FDA dosing and administration

Investigational uses: All other uses of the above-named agents when used for conditions not outlined in this policy are investigational

Denial Risk

Investigational uses not covered

All other uses of the agents listed in this policy that are not described here or in policy 5.01.606 are considered investigational and are not covered.

Applicable Codes

HCPCS CodesHCPCS

S0145

Injection, PEGylated interferon alfa-2A (Pegasys), 180 mcg per ml

Provider Actions & Authorization Requirements

Prior Authorization

Pharmacy benefit management and prior authorization

Baraclude, Pegasys, and Vemlidy are managed through the pharmacy benefit; prior authorization is implied by the policy coverage criteria. Initial approvals may be for up to 12 months.

Documentation Required

Required medical record documentation

Office visit notes must document diagnosis, relevant history, physical evaluation, HBV DNA (viral load), and medication history to demonstrate medical necessity.

Clinical Evidence Summary

67-90%Baraclude adult trials: 67%-90% undetectable HBV DNA (<300 copies/mL) vs lamivudine 36%-72%

32-43%Pegasys adult studies: 32%-43% achieving specified HBV DNA thresholds at week 48

92% / 63%Vemlidy trials: Trial 108 92% <29 IU/mL; Trial 110 63% <29 IU/mL at week 48

Clinical trial evidence supports antiviral efficacy for these agents: Baraclude demonstrated high rates of undetectable HBV DNA in adult trials and pediatric studies; Pegasys trials (Studies 8, 9, 10) showed virologic responses in adults and children though with lower proportions versus lamivudine in some endpoints; Vemlidy trials (108/110 and switch studies) showed high rates of HBV DNA suppression at week 48 and benefit when switching from TDF. The policy references the AASLD practice guideline for chronic hepatitis B (2026) as guidance for treatment selection. Coinfection considerations are highlighted: in HCV/HBV coinfection, HBV therapy (e.g., entecavir or tenofovir agents) should be started concurrently with direct-acting antiviral HCV therapy to prevent HBV reactivation; HIV/HBV coinfected persons require combination antiretroviral regimens with agents active against both viruses; persons with risk factors should be tested for HDV and Pegasys has a listed indication for compensated HDV treatment.

Background

Background: Chronic hepatitis B (CHB) affects hundreds of millions worldwide and contributes substantially to cirrhosis and hepatocellular carcinoma; many affected persons in the U.S. are undiagnosed. The AASLD 2026 guideline lists preferred antiviral therapies for adults and children as peginterferon alfa-2a, entecavir, tenofovir disoproxil fumarate, and tenofovir alafenamide. Coinfection considerations: direct-acting antiviral HCV therapy can precipitate HBV reactivation, so HBV antiviral therapy (entecavir, TDF, or TAF) should be given concurrently in HCV/HBV coinfection; HIV/HBV coinfected individuals require antiretroviral regimens that include at least two agents active against HBV due to resistance concerns with monotherapy; persons at risk should be tested for HDV, and Pegasys is included for treatment of compensated HDV. Definitions: Chronic hepatitis B (CHB) — HBsAg positive for at least 6 months with variable HBV DNA and possible HBeAg positivity or negativity; ALT/AST may be normal or elevated. Immune-Active CHB — HBsAg ≥6 months with HBV DNA >20,000 IU/mL (HBeAg-positive) or >2,000 IU/mL (HBeAg-negative) and intermittently or persistently elevated ALT/AST with moderate/severe necroinflammation. Immune-tolerant CHB — HBsAg ≥6 months, HBeAg positive, very high HBV DNA (typically >1,000,000 IU/mL), and normal or minimally elevated ALT/AST with minimal inflammation/fibrosis.

Revision History

2026-04-14approved (material)Latest

Policy approved April 14, 2026 (effective May 1, 2026) with material updates to Pegasys criteria: added indications for polycythemia vera, essential thrombocytopenia (first- or second-line), and treatment of hepatitis D virus; clarified myelofibrosis criteria specifying JAK2 V617F mutation.

2024-06-01revised (material)

Annual review (approved May 14, 2024) updated Vemlidy age requirement to 6 years or older and added requirement that adults and pediatric individuals weighing ≥35 kg try generic tenofovir disoproxil fumarate with inadequate response or intolerance before Vemlidy.

2024-06-01