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Recruiting Phase 2 NCT04954859

NCT04954859 Long-term Follow-up Study to Evaluate Durability of Treatment Response in Previous Bepirovirsen Study Participants (B-Sure)

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Clinical Trial Summary
NCT ID NCT04954859
Status Recruiting
Phase Phase 2
Sponsor GlaxoSmithKline
Condition Hepatitis B
Study Type INTERVENTIONAL
Enrollment 450 participants
Start Date 2021-12-14
Primary Completion 2029-02-08

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
BepirovirsenPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

In Phase 2, researchers evaluate early signs of effectiveness. You may be randomized to receive the active treatment or a comparator. Monitoring continues closely.

This trial targets 450 participants in total. It began in 2021-12-14 with a primary completion date of 2029-02-08.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This is a global multi-center, long-term follow-up study to assess durability of efficacy, as measured by maintenance of treatment response from the parent study, in participants who participated in a previous bepirovirsen study and achieved a complete or partial response. Eligible participants will be enrolled in this study after completing the end of study (EoS) visit in the respective parent bepirovirsen studies (studies B-Clear \[209668: NCT04449029\], B-Together \[209348: NCT04676724\], B-Fine \[212602: NCT04544956\], B-Well 1 \[202009: NCT05630807\], B-Well 2 \[219288: NCT05630820\], and TH HBV ASO-001 \[217023: NCT05276297\]). Participants will be categorized as Not-on-NA, NA-cessated, or On-NA based on their nucleos(t)ide analogue (NA) status in the parent study. No further treatment with bepirovirsen will be administered in this study.

Eligibility Criteria

Inclusion criteria: * Participants who enter the study on stable NA are willing and able to cease their NA treatment in accordance with the NA cessation schedule. * Capable of giving informed consent. For participants rolling over from 209668 (B-Clear), 209348 (B-Together), and 212602 (B-Fine): * Participants who have previously received at least one dose of bepirovirsen AND 1. Achieved the PSPO in the parent study and who maintained a response until the End of Study (EoS) visit in their parent study (defined as complete responders to bepirovirsen from the parent study) OR 2. Demonstrated hepatitis B virus surface antigen (HBsAg) reduction greater than or equal to (≥) 1.0 log10 international units per milliliter (IU/mL) from parent study Baseline with HBsAg levels less than (\<) 100 IU/mL and HBV deoxyribonucleic acid (DNA) \< lower limit of quantification (LLOQ) for 24 weeks after the actual end of treatment regimen, in the absence of rescue medication and maintained until their EoS visit in the parent study. For participants rolling over from 202009 (B-Well1) and 219288 (B-Well 2): * Participants who have previously received at least 1 dose of bepirovirsen (or matching placebo where appropriate) AND 1. NA cessated at Week 48 in parent study and achieved at least HBsAg \<1 IU/ml and HBV DNA \<LLOQ at the EOS visit (Week 96) in the parent study OR 2. Achieved NA cessation criteria at Week 48 in parent study but have not stopped NA treatment, and are maintaining at least HBsAg \<1 IU/ml and HBV DNA \<LLOQ at EOS visit (Week 72) of parent study OR 3. Did not achieve NA cessation criteria in parent study but achieved at least HBsAg \<1 IU/ml and HBV DNA \<LLOQ at EOS visit (Week 72) of parent study. For participants rolling over from 217023 (TH HBV ASO-001): * Participants who have previously received at least 1 dose of bepirovirsen AND 1. Achieved HBsAg \<1 IU/ml and HBV DNA \<LLOQ in parent study at Week 66 (ASO12 arm) or Week 78 (ASO 24 arm) and are maintaining HBsAg \< 1 IU/ml and HBV DNA \<LLOQ, at the EOS study visit \[Week 133 ASO12 arm), or Week 145 (ASO24 arm)\] in parent study OR 2. Did not achieve HBsAg \<1 IU/ml and HBV DNA \<LLOQ in parent study at Week 66 (ASO12 arm) or Week 78 (ASO24 arm) but have achieved HBsAg \< 1 IU/ml and HBV DNA \< LLOQ by the EOS visit (Week 133 (ASO12 arm) or Week 145 (ASO24 arm)) in the parent study. Exclusion Criteria: * Participants who have/or are currently participating in another non-GSK interventional clinical study exploring HBV treatment since completing their treatment with bepirovirsen. * Any condition which, in the opinion of the investigator or Medical Monitor, contraindicates their participation in this study.

Contact & Investigator

Central Contact

US GSK Clinical Trials Call Center

✉ GSKClinicalSupportHD@gsk.com

📞 877-379-3718

Principal Investigator

GSK Clinical Trials

STUDY DIRECTOR

GlaxoSmithKline

Frequently Asked Questions

Who can join the NCT04954859 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Hepatitis B. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT04954859 trial and what does that mean for participants?

Phase 2 trials evaluate whether the treatment shows signs of effectiveness while continuing to monitor safety. More participants are enrolled than in Phase 1 to help refine the treatment protocol.

Is NCT04954859 currently recruiting?

Yes, NCT04954859 is actively recruiting participants. Contact the research team at GSKClinicalSupportHD@gsk.com for enrollment information.

Where is the NCT04954859 trial being conducted?

This trial is being conducted at Sacramento, United States, Boston, United States, Detroit, United States, Buenos Aires, Argentina and 11 additional locations.

Who is sponsoring the NCT04954859 clinical trial?

NCT04954859 is sponsored by GlaxoSmithKline. The principal investigator is GSK Clinical Trials at GlaxoSmithKline. The trial plans to enroll 450 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology