A Study of ABI-H0731 + Nucleos(t)Ide as Finite Treatment for Chronic Hepatitis B Patients

Open-label, extension study to evaluate the safety and efficacy of combination therapy and its effect on sustained viral response biomarkers.

This is an open-label extension of parent studies ABI-H0731-201 (NCT03576066) and ABI-H0731-202 (NCT03577171). The extension study will assess the safety of long-term (up to 100 weeks of treatment in extension study ABI-H0731-211) combination therapy and its effect on biomarkers of sustained viral response (SVR) (NCT03780543).

Eligibility Criteria:
Inclusion Criteria:

1. Willing and able to provide informed consent.
2. Previously enrolled on Study ABI-H0731-201 (NCT03576066) or ABI-H0731-202 (NCT03577171) and completed the treatment period, with demonstrated compliance in the opinion of the investigator.
3. Female subjects must agree to use an effective birth control method for the duration of the study and follow-up, or be surgically sterile for at least 6 months, or at least 2 years postmenopausal with serum follicle-stimulating hormone (FSH) levels consistent with a postmenopausal status. Effective birth control methods include male or female condom (may not be used together due to increased risk of breakage), vasectomy, intrauterine device (IUD), diaphragm, or cervical cap. Female subjects of childbearing potential must have a negative serum pregnancy test.
4. All heterosexually active male subjects must agree to use an effective birth control method for the duration of the study and follow-up. Effective birth control methods include male or female condom (may not be used together due to increased risk of breakage), vasectomy, hormone-based contraception (only female partner of a male subject), IUD, diaphragm, or cervical cap.
5. Agreement to adhere to Lifestyle Considerations (including abstaining from alcohol abuse \[defined as alcohol consumption exceeding 2 standard drinks per day on average (1 standard drink = 10 grams of alcohol)\] and the use of illicit substances, herbal or other substances, or unnecessary over-the-counter medications throughout study duration.
6. In good general health except for chronic HBV infection.
7. Have the ability to take oral medication and be willing to adhere to the ABI-H0731-211 regimen in the opinion of the Investigator.

Exclusion Criteria:

1. Must not have had evidence of HBV resistance-associated variants (RAVs) or lack of compliance on a previous study of ABI H0731.
2. Must not have had a treatment-emergent adverse event or laboratory abnormalities deemed clinically significant and possibly or probably related to drug while on a previous study of ABI-H0731, that in the opinion of the Investigator or the Sponsor makes the subject unsuitable for this study.
3. Current clinically significant cardiac or pulmonary disease, chronic or recurrent renal or urinary tract disease, liver disease other than HBV, endocrine disorder, autoimmune disorder, diabetes mellitus requiring treatment with insulin or hypoglycemic agents, neuromuscular, musculoskeletal, or mucocutaneous conditions requiring frequent treatment, seizure disorders requiring treatment, or other medical conditions requiring frequent medical management or pharmacologic or surgical treatment that in the opinion of the Investigator or the Sponsor makes the subject unsuitable for the study.
4. Females who are lactating or pregnant or wish to become pregnant within the duration of the ABI-H0731-211 study.