CLINICAL TRIALS PROFILE FOR HEPSERA

All Clinical Trials for HEPSERA

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00158704 ↗	Continued Access Study of Adefovir Dipivoxil (ADV) for Patients w/Chronic HBV Infection.	Terminated	Gilead Sciences	N/A	2002-01-01	Provide adefovir dipivoxil (Hepsera) 10 mg once daily to patients with chronic hepatitis B virus (HBV) infection who have completed a Gilead-sponsored study of adefovir dipivoxil and require continued access to adefovir dipivoxil.
NCT00158717 ↗	Observational Study of the Durability of Seroconversion Chronic HBV Patients Who Seroconverted in a Previous Gilead-Sponsored Study of ADV.	Completed	Gilead Sciences		2003-04-01	To investigate the durability of HBeAg seroconversion in patients with chronic hepatitis B virus infection (HBV) who have seroconverted while participating in a previous Gilead-sponsored study of adefovir dipivoxil.
NCT00230477 ↗	Hepsera Versus Hepsera Plus Lamivudine for Treatment of Chronic Hepatitis B in Patients With Normal ALT	Completed	Gilead Sciences	Phase 4	2003-04-01	This project is a randomized, open-label trial of adefovir dipivoxil (Hepsera) and lamivudine combination therapy versus adefovir dipivoxil (Hepsera) monotherapy. Both adefovir dipivoxil and lamivudine are nucleoside analogues approved by the U.S. FDA for the treatment of chronic hepatitis B. The primary hypothesis is that subjects treated with combination therapy will see their viral DNA count decrease in an amount greater than subjects treated with monotherapy. The secondary hypothesis is that subjects treated with combination therapy will have a higher HBeAg conversion rate compared to historical controls of subjects treated with lamivudine or adefovir dipivoxil monotherapy.
NCT00230477 ↗	Hepsera Versus Hepsera Plus Lamivudine for Treatment of Chronic Hepatitis B in Patients With Normal ALT	Completed	GlaxoSmithKline	Phase 4	2003-04-01	This project is a randomized, open-label trial of adefovir dipivoxil (Hepsera) and lamivudine combination therapy versus adefovir dipivoxil (Hepsera) monotherapy. Both adefovir dipivoxil and lamivudine are nucleoside analogues approved by the U.S. FDA for the treatment of chronic hepatitis B. The primary hypothesis is that subjects treated with combination therapy will see their viral DNA count decrease in an amount greater than subjects treated with monotherapy. The secondary hypothesis is that subjects treated with combination therapy will have a higher HBeAg conversion rate compared to historical controls of subjects treated with lamivudine or adefovir dipivoxil monotherapy.
NCT00230477 ↗	Hepsera Versus Hepsera Plus Lamivudine for Treatment of Chronic Hepatitis B in Patients With Normal ALT	Completed	University of Washington	Phase 4	2003-04-01	This project is a randomized, open-label trial of adefovir dipivoxil (Hepsera) and lamivudine combination therapy versus adefovir dipivoxil (Hepsera) monotherapy. Both adefovir dipivoxil and lamivudine are nucleoside analogues approved by the U.S. FDA for the treatment of chronic hepatitis B. The primary hypothesis is that subjects treated with combination therapy will see their viral DNA count decrease in an amount greater than subjects treated with monotherapy. The secondary hypothesis is that subjects treated with combination therapy will have a higher HBeAg conversion rate compared to historical controls of subjects treated with lamivudine or adefovir dipivoxil monotherapy.
NCT00307489 ↗	Treatment of Persistent Viremia (Virus in Blood) in Chronic Hepatitis B Subjects Already Receiving Adefovir Dipivoxil	Completed	Gilead Sciences	Phase 2	2006-03-01	This study explores the efficacy, safety and tolerability of tenofovir DF (TDF) 300 mg once daily monotherapy versus the combination of emtricitabine 200 mg plus tenofovir DF 300 mg (FTC/TDF) once daily in subjects currently being treated with adefovir dipivoxil (Hepsera) for chronic hepatitis B who have persistent viral replication (detectable hepatitis B virus deoxyribonucleic acid [HBV DNA]). Subjects with confirmed (within 4 weeks) plasma HBV DNA ≥ 400 copies/mL during double blind treatment at Week 24 or any time thereafter have the option of receiving 12 weeks of open-label FTC/TDF which may be continued through the end of the 168-week treatment period if there is a virologic response (HBV DNA < 400 copies/mL). Alternatively, subjects with confirmed HBV DNA < 400 copies/mL at or any time after Week 24 of double-blind treatment may continue blinded therapy up to Week 168 at the discretion of the investigator. If, in the investigator's opinion, it is felt that continued blinded treatment beyond 24 weeks in subjects with confirmed HBV DNA ≥ 400 copies/mL is not beneficial, the subject may discontinue the study and begin commercially available HBV therapy rather than initiate open-label FTC/TDF.
NCT00371761 ↗	PegIntron Versus Adefovir in the Treatment of Chronic Hepatitis B (CHB) e Antigen Positive Patients in Taiwan (P04498/MK-4031-278)	Completed	Merck Sharp & Dohme Corp.	Phase 3	2006-09-01	This is an open label, randomized, comparative, multi-center study. Subjects will be screened within 2 weeks prior to study entry to establish eligibility. Subjects who meet all the selection criteria will be randomly assigned 1:1 to (1) once-a-week, subcutaneous Pegylated interferon alfa-2b (PegIntron) (1.5 mcg/kg body weight) or (2) oral adefovir 10 mg daily. The treatment phase will be 24 weeks for PegIntron and 48 weeks for adefovir. All subjects completing the assigned treatment phase will be followed up for an additional 48 weeks for PegIntron and 24 weeks for adefovir as observation phase. The primary objective is to establish the efficacy profile of PegIntron. Secondary objectives are to compare the efficacy profile of PegIntron with that of adefovir, compare efficacy of PegIntron in lamivudine-naïve and lamivudine-experienced subjects, and to establish the safety profile of PegIntron in treating patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B.

Clinical Trial Conditions for HEPSERA

Condition Name

Condition Name for HEPSERA
Intervention	Trials
Hepatitis B	7
Chronic Hepatitis B	5
Hepatitis B, Chronic	4
Liver Transplantation	1

Condition MeSH

Condition MeSH for HEPSERA
Intervention	Trials
Hepatitis B	18
Hepatitis	15
Hepatitis B, Chronic	13
Hepatitis A	12

Clinical Trial Locations for HEPSERA

Trials by Country

Trials by Country for HEPSERA
Location	Trials
Korea, Republic of	11
United States	8
Hong Kong	3
Malaysia	2
Spain	2

Trials by US State

Trials by US State for HEPSERA
Location	Trials
New York	2
California	2
Connecticut	1
Virginia	1
Pennsylvania	1

Clinical Trial Progress for HEPSERA

Clinical Trial Phase

Clinical Trial Phase for HEPSERA
Clinical Trial Phase	Trials
Phase 4	7
Phase 3	4
Phase 2	2

Clinical Trial Status

Clinical Trial Status for HEPSERA
Clinical Trial Phase	Trials
Completed	13
Unknown status	3
Terminated	2

Clinical Trial Sponsors for HEPSERA

Sponsor Name

Sponsor Name for HEPSERA
Sponsor	Trials
Gilead Sciences	5
GlaxoSmithKline	4
Bristol-Myers Squibb	3

Sponsor Type

Sponsor Type for HEPSERA
Sponsor	Trials
Other	27
Industry	18

HEPSERA (Adefovir Dipivoxil): Clinical Trials, Market Analysis, and Projections

Last updated: February 21, 2026

What is the current status of HEPSERA's clinical trials?

HEPSERA, marketed as Adefovir Dipivoxil, was approved by the U.S. Food and Drug Administration in 2002 for chronic hepatitis B virus (HBV) infections. The drug's development covered numerous phases prior to approval, focusing on safety, efficacy, and long-term outcomes.

Completed Clinical Trials

• Phase 1: Established pharmacokinetics, safety, and dosing in healthy volunteers.
• Phase 2: Demonstrated antiviral activity in chronic HBV patients; optimized dosage.
• Phase 3: Confirmed efficacy and safety over 48 weeks in HBV-infected patients, leading to regulatory approval.

Ongoing and Supplemental Trials

Post-approval, HEPSERA has undergone certain post-marketing studies:

• Long-term Safety: Studies extending treatment duration beyond initial trials.
• Resistance Development: Monitoring for drug-resistant HBV strains over multiple years.
• Combination Therapy: Trials exploring HEPSERA with other antivirals for enhanced efficacy.

No recent large-scale Phase 3 or Phase 4 trials are actively recruiting as of 2023. The drug's development trajectory has largely shifted to chronic management and resistance monitoring rather than new indications.

How does the current market landscape for HEPSERA compare to alternatives?

Competitive Antivirals for HBV

Drug Name	Approved Date	Mechanism	Efficacy Profile	Resistance Development	Market Share (2022)
HEPSERA (Adefovir)	2002	Nucleotide analog	Moderate	Higher than newer agents	12%
Viread (Tenofovir Disoproxil Fumarate)	2001	Nucleotide analog	High	Lower	45%
Baraclude (Entecavir)	2005	Nucleoside analog	High	Very low	30%
Tenofovir Alafenamide (TAF)	2015	Prodrug of tenofovir	High	Very low	10%

HEPSERA remains a treatment option but has lost market dominance due to issues like resistance, daily dosing requirements, and newer drugs with improved safety profiles.

Market Size and Revenue

• Global HBV antiviral market was valued at approximately USD 4.2 billion in 2022.
• HEPSERA's share is estimated at USD 0.5 billion, primarily stemming from long-term therapy commitments in Europe, Asia, and U.S.
• Competition from tenofovir and entecavir has constrained growth prospects.

What are the future market projections for HEPSERA?

Treatment Guidelines and Prescribing Trends

• Major guidelines (AASLD, EASL) favor tenofovir-based therapies due to higher potency and lower resistance.
• HEPSERA prescribed mainly for patients intolerant to first-line agents or with specific resistance profiles.

Market Forecast (2023-2030)

Year	Estimated Market Share	Projected Revenue (USD)	Key Drivers
2023	8%	At USD 0.4 billion	Continued use in resistant cases
2025	6%	USD 0.3 billion	Competitive pressure from newer drugs
2030	4%	USD 0.2 billion	Decline due to evolving treatment standards

The decline correlates with the shift toward tenofovir and entecavir as first-line therapies. HEPSERA’s niche remains in specific cases where resistance or tolerability issues limit alternative options.

What are the key factors influencing HEPSERA's market outlook?

• Resistance Patterns: Emergence of HBV strains resistant to adefovir limits long-term use.
• Safety Profiles: Better tolerated and safer drugs (e.g., TAF) are replacing HEPSERA.
• Regulatory Changes: Potential updates to guidelines may further restrict HEPSERA's role.
• Pricing Strategies: Discounting and reimbursement policies impact market penetration.

What is the potential for new formulations or combination regimens?

No recent development of novel formulations has been publicly disclosed for HEPSERA. Its pharma manufacturer may explore:

• Fixed-dose combination pills with other antivirals.
• Phased-out formulations to improve safety or compliance.
• Developing resistance monitoring tools.

However, the strategic focus appears limited given the drug’s existing market position and competition.

Summary

HEPSERA’s clinical trial activity has been minimal since its initial approval, primarily limited to post-marketing safety and resistance monitoring. Its market presence diminishes as newer drugs with superior efficacy, safety, and resistance profiles dominate, leading to a forecasted market share decline from 2023 to 2030. The drug remains relevant for specific resistant HBV cases but faces obsolescence risks in general treatment protocols.

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Key Takeaways

• HEPSERA was approved in 2002 for HBV treatment, with ongoing post-marketing safety and resistance assessments.
• Available data show reduced market share due to competition from tenofovir and entecavir.
• Market forecasts predict a sharp decline by 2030, driven by evolving treatment guidelines favoring newer antivirals.
• No recent clinical trials or formulation innovations are currently underway for HEPSERA.
• The drug’s future is limited to niche applications, with resistance and safety profiles driving obsolescence.

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FAQs

1. Has HEPSERA received any recent regulatory updates?
No, the drug has not undergone major regulatory revisions beyond initial approval and post-marketing safety updates.

2. Are there ongoing clinical trials for HEPSERA?
No active clinical trials for new indications or formulations are publicly disclosed as of 2023.

3. What factors limit HEPSERA's market growth?
Resistance development, safety concerns, and competition from tenofovir and entecavir limit its growth.

4. Can HEPSERA be combined with other HBV therapies?
Yes, but such combinations are mainly studied post-approval for resistance management; commercial use is limited.

5. What is the primary niche for HEPSERA now?
Use is mainly for patients with resistance or intolerance to first-line antivirals.

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References

1. U.S. Food and Drug Administration (FDA). (2002). HEPSERA (Adefovir Dipivoxil) Prescribing Information.
2. World Health Organization (WHO). (2022). Global hepatitis report.
3. MarketWatch. (2023). HBV antiviral market analysis.
4. American Association for the Study of Liver Diseases (AASLD). (2022). HBV treatment guidelines.
5. European Association for the Study of the Liver (EASL). (2022). Clinical practice guidelines on hepatitis B management.