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Dose-Escalation Prime/Boost Therapeutic Vaccination Study Of 2 Chimp Adenoviral Vectors in Adults With Chronic HBV On Nucleos(t)Ide Therapy

Phase 1
Recruiting
Conditions
Chronic Hepatitis B
Interventions
Biological: VRON-0200-AdC6
Biological: VRON-0200-AdC7
Registration Number
NCT06070051
Lead Sponsor
Virion Therapeutics
Brief Summary

This Phase 1b clinical study is a multi-center, open-label, dose escalation, prime only, and prime plus boost therapeutic vaccination study of 2 distinct chimpanzee adenoviral vectors (AdC6 and AdC7), containing parts of hepatitis B virus (HBV) core and polymerase antigens fused within glycoprotein D in a cohort of chronic hepatitis B (CHB)-infected adult participants who are currently receiving entecavir, tenofovir (tenofovir alafenamide fumarate or tenofovir disoproxil fumarate), or lamivudine, with documented HBV viral load suppression for at least 12 months.

Approximately 24 participants will be enrolled in Group 1 and randomized to Cohort 1a or Cohort 1b. Those assigned to Cohort 1a will receive a low dose prime therapeutic vaccination of vector AdC7 on Day 1, followed by a booster vaccination on Day 91 using vector AdC6. Those assigned to Cohort 1b will receive a low dose prime therapeutic vaccination of vector AdC6 on Day 1, and will not receive a booster vaccination.

Group 2 will then enroll approximately 24 participants randomized to Cohort 2a or Cohort 2b. Those assigned to Cohort 2a will receive a high dose prime therapeutic vaccination of vector AdC7 on Day 1, followed by a booster vaccination on Day 91 using vector AdC6. Those assigned to Cohort 2b will receive a high dose prime therapeutic vaccination of vector AdC6 on Day 1, and will not receive a booster vaccination.

All vaccine doses will be administered by intramuscular (IM) injection.

All study participants will be followed for a total of 1 year post-prime vaccination.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
48
Inclusion Criteria
  1. Documented chronic HBV infection (eg, HBsAg+ ≥ 6 months with detectable HBsAg at screening)
  2. Receipt of either entecavir, tenofovir (tenofovir alafenamide fumarate or tenofovir disoproxil fumarate), or lamivudine for at least 12 months before screening with no reported antiviral resistance during this time; still on treatment at screening and expected to stay on therapy during the study period
  3. Virally suppressed for > 12 months (HBV DNA < 40 IU/mL)
  4. No clinical diagnosis of advanced liver fibrosis and/or cirrhosis
Exclusion Criteria
  1. History of hepatic decompensation, advanced fibrosis, or liver transplantation
  2. History of hepatocellular carcinoma
  3. History of risk factors for thrombosis and thrombocytopenia
  4. Documented hepatitis A, hepatitis C, hepatitis D, hepatitis E, or HIV (or history of prior active disease)
  5. Pregnant, nursing, or planning a pregnancy during the trial

Study & Design

Study Type
INTERVENTIONAL
Study Design
SEQUENTIAL
Arm && Interventions
GroupInterventionDescription
Cohort 3b: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, No BoostVIR-2218Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will not receive a boost vaccination.
Cohort 1a: Low Dose VRON-0200-AdC7 Prime, VRON-0200-AdC6 BoostVRON-0200-AdC6Participants assigned to Cohort 1a will receive a low dose prime vaccination of AdC7 vector on Day 1. They will receive a low dose boost vaccination of vector AdC6 on Day 91.
Cohort 1a: Low Dose VRON-0200-AdC7 Prime, VRON-0200-AdC6 BoostVRON-0200-AdC7Participants assigned to Cohort 1a will receive a low dose prime vaccination of AdC7 vector on Day 1. They will receive a low dose boost vaccination of vector AdC6 on Day 91.
Cohort 1b: Low Dose VRON-0200-AdC6 Prime, No BoostVRON-0200-AdC6Participants assigned to Cohort 1b will receive a low dose prime vaccination of AdC6 vector on Day 1. They will not receive a booster vaccination.
Cohort 2a: High Dose VRON-0200-AdC7 Prime, VRON-0200-AdC6 BoostVRON-0200-AdC6Participants assigned to Cohort 2a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 2a: High Dose VRON-0200-AdC7 Prime, VRON-0200-AdC6 BoostVRON-0200-AdC7Participants assigned to Cohort 2a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 2b: High Dose VRON-0200-AdC6 Prime, No BoostVRON-0200-AdC6Participants assigned to Cohort 2b will receive a high dose prime vaccination of AdC6 vector on Day 1. They will not receive a booster vaccination.
Cohort 3a: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, VRON-0200-AdC6 BoostVRON-0200-AdC6Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 3a: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, VRON-0200-AdC6 BoostVRON-0200-AdC7Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 3a: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, VRON-0200-AdC6 BoostVIR-2218Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 3a: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, VRON-0200-AdC6 BoostVIR-3434Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will receive a high dose boost vaccination of AdC6 vector on Day 91.
Cohort 3b: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, No BoostVRON-0200-AdC7Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will not receive a boost vaccination.
Cohort 3b: High Dose VRON-0200-AdC7 Prime, 6 Doses VIR-2218 + VIR-3434, No BoostVIR-3434Participants assigned to Cohort 3a will receive a high dose prime vaccination of AdC7 vector on Day 1. They will receive VIR-2218 and VIR-3434 on Days 28, 56, 84, 112, 140, and 168. They will not receive a boost vaccination.
Primary Outcome Measures
NameTimeMethod
Treatment Emergent Adverse Events28 days

Number and percent of participants with 1 or more treatment-emergent adverse events within 28 days after the last dose by cohort.

Grade 3 Adverse Events28 days

Number and percent of participants with Grade 3 or higher local and/or systemic reactions within 28 days after the last dose by cohort.

Clinically Significant Changes in Lab Values28 days

Number and percent of participants with clinically significant changes from pre-vaccination laboratory values within 28 days after the last dose by cohort.

Serious Adverse Events6 months

Number and percent of participants with serious adverse events within 6 months after the last dose by cohort.

Medically Attended Adverse Events6 months

Number and percent of participants with medically attended adverse events within 6 months after the last dose by cohort.

Secondary Outcome Measures
NameTimeMethod
Adverse Events360 days

Number and percentage of adverse events for all participants through Day 360.

T Cell Frequencies360 days

Change from baseline in vaccine-induced CD8+ T cell frequencies in the blood.

Trial Locations

Locations (3)

Aotearoa Clinical Trials, Middlemore Hospital

🇳🇿

Auckland, New Zealand

Chinese University of Hong Kong

🇭🇰

Hong Kong, Hong Kong

Auckland City Hospital

🇳🇿

Auckland, New Zealand

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