Conditions: Hepatitis B
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 12
Healthy volunteers: no

Brief summary:
Chronic HBV patients will receive 9 doses of open-label ARC-520 once every 4 weeks and be evaluated for safety and efficacy.

Detailed description:
Open-label, multi-center extension study of intravenous ARC-520 in combination with entecavir or tenofovir in patients with chronic HBV infection. Patients who successfully completed the Heparc-2002 (NCT02604199) and Heparc-2003 (NCT02604212) studies and responded to therapy are eligible to participate. Responders are defined as patients who showed a ½ log or greater reduction in their serum Hepatitis B Surface Antigen (HBsAg) levels from baseline to day 71 ± 3 days of the primary Heparc-2002 and Heparc-2003 studies. Patients who have signed a Human Research Ethics Committee approved informed consent and have met all of the protocol eligibility criteria will continue receiving daily oral entecavir or tenofovir and intravenous (IV) injections of ARC-520. Study visits will occur once every 4 weeks for a total of 9 visits for monitoring and ARC-520 administration.

Patients will undergo the following evaluations at regular intervals during the study: medical history, physical examinations, vital sign measurements (blood pressure, heart rate, respiratory rate and temperature), weight, adverse events (AEs), 12-lead electrocardiograms (ECGs), concomitant medications, blood sample collection for hematology, coagulation, chemistry, creatine kinase, troponin, hemoglobin A1c, exploratory pharmacodynamic (PD) measures, urinalysis, HBV serology, immunogenicity, and pregnancy testing for females of childbearing potential. Patients will be monitored for HBV virology, AEs, and exploratory PD measures for a total of 24 weeks after the last dose of ARC-520.

Arms:
arm 1: Multiple administrations of ARC-520 starting at a dose level of 2 mg/kg, plus entecavir (0.5 or 1.0 mg/day) or tenofovir (300 mg/day)

Interventions: intervention 1: ARC-520 Injection intervention 2: entecavir intervention 3: tenofovir intervention 4: antihistamine
Intervention descriptions: intervention 1: IV injection intervention 2: All participants will take entecavir or tenofovir throughout the study. Participants will be instructed to take their medication daily. intervention 3: All participants will take entecavir or tenofovir throughout the study. Participants will be instructed to take their medication daily. intervention 4: All participants will be pretreated with an oral antihistamine. The antihistamine used should in general be an H1\>H2 receptor blocker and would include diphenhydramine 50 mg, cetirizine 10 mg, chlorpheniramine 8 mg or hydroxyzine 50 mg. The Investigator is free to choose any of these antihistamines available locally and consistent with their country's Marketing Authorisation.

Protocol document: