A Phase 2 interventional study of HepTcell and Placebo in Hepatitis B, Chronic, sponsored by Altimmune, Inc.. Terminated at 21 sites in 5 countries. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-12-08.
Sponsored by Altimmune, Inc. · Phase 2, Interventional, and Treatment
A study to evaluate the antiviral effects, immunogenicity, and safety of HepTcell in treatment-naive patients with inactive chronic hepatitis B (CHB) and low hepatitis B surface antigen (HBsAg) levels.
Exclusion Criteria:
Dose administered at intervals of 4 weeks for 6 doses
Biological: HepTcell
Dose administered at intervals of 4 weeks for 6 doses
Drug: Placebo
Intramuscular injection
Intramuscular injection
The Proportion of Patients Achieving Virologic Responses
Virologic response is defined as a 1.0-log reduction in quantitative hepatitis B surface antigen (HBsAg) or serologic clearance of HBsAg from Baseline to Day 169
Time frame: Baseline to Day 169
The Proportion of Patients Achieving Serologic Clearance of Hepatitis B Surface Antigen (HBsAg) on Day 169
Time frame: Baseline to Day 169
The Proportion of Patients Achieving Serologic Clearance of Hepatitis B Virus (HBV) DNA on Day 169
Time frame: Baseline to Day 169
Changes in Quantitative HBsAg Level
Time frame: Baseline to Days 85 and 169
Changes in HBV DNA Levels
Time frame: Baseline to Days 85 and 169
Changes in Hepatitis B Core-related Antigen (HBCrAg) Levels
Time frame: Baseline to Days 85 and 169
Changes in Pre-genomic RNA Levels
Time frame: Baseline to Days 85 and 169
Change in IFN-gamma Frequency by ELISpot Assay in PBMCs
Percent change in antigen-specific spot forming cells per million peripheral blood mononuclear cells (PBMCs)
Time frame: Baseline to Days 85 and 169
| Milestone | HepTcell | Placebo |
|---|---|---|
| Started | 42 | 45 |
| Treated | 41 | 43 |
| Completed | 40 | 43 |
| Not completed | 2 | 2 |
| Withdrew: Withdrawal by subject | 1 | 0 |
| Withdrew: Discontinued before receiving study treatment | 1 | 2 |
Virologic response is defined as a 1.0-log reduction in quantitative hepatitis B surface antigen (HBsAg) or serologic clearance of HBsAg from Baseline to Day 169
| Participants | HepTcell | Placebo |
|---|---|---|
| The Proportion of Patients Achieving Virologic Responses | 1 | 0 |
| Participants | HepTcell | Placebo |
|---|---|---|
| The Proportion of Patients Achieving Serologic Clearance of Hepatitis B Surface Antigen (HBsAg) on Day 169 | 1 | 0 |
| Participants | HepTcell | Placebo |
|---|---|---|
| The Proportion of Patients Achieving Serologic Clearance of Hepatitis B Virus (HBV) DNA on Day 169 | 5 | 8 |
| IU/mL | HepTcell | Placebo |
|---|---|---|
| Day 85 | -7.76 ± 28.01 | -8.47 ± 15.85 |
| Day 169 | -13.72 ± 32.80 | -10.19 ± 31.87 |
| IU/mL | HepTcell | Placebo |
|---|---|---|
| Day 85 | -7559.73 ± 46650.54 | -5270.05 ± 33240.79 |
| Day 169 | -7868.48 ± 44871.40 | -4690.12 ± 32070.75 |
| kU/mL | HepTcell | Placebo |
|---|---|---|
| Day 85 | -4.00 ± 7.81 | 1.00 ± NA |
| Day 169 | -1.00 ± 1.00 | 1.00 ± NA |
| Log U/mL | HepTcell | Placebo |
|---|---|---|
| Day 85 | 0.26 ± 0.42 | 0.16 ± 0.39 |
| Day 169 | 0.31 ± 0.44 | 0.30 ± 0.48 |
Percent change in antigen-specific spot forming cells per million peripheral blood mononuclear cells (PBMCs)
| percent change | HepTcell | Placebo |
|---|---|---|
| Day 85 | 3.71 ± 39.02 | -0.14 ± 21.50 |
| Day 169 | -5.28 ± 28.56 | 3.45 ± 45.56 |
Collected over 6 months. Non-serious events are listed at a 2% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| HepTcell | 0/41 (0%) | 0/41 (0%) | 19/41 (46.3%) |
| Placebo | 0/43 (0%) | 0/43 (0%) | 29/43 (67.4%) |
| Event | HepTcell | Placebo |
|---|---|---|
| COVID-19Infections and infestations | 6/41 | 4/43 |
| Back painMusculoskeletal and connective tissue disorders | 3/41 | 3/43 |
| Neutrophil count decreasedInvestigations | 1/41 | 3/43 |
| HeadacheNervous system disorders | 2/41 | 2/43 |
| PyrexiaGeneral disorders | 2/41 | 2/43 |
| DiarrheaGastrointestinal disorders | 1/41 | 2/43 |
| Food poisoningGastrointestinal disorders | 0/41 | 2/43 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 1/41 | 2/43 |
| Influenza A virus test positiveInvestigations | 0/41 | 2/43 |
| FatigueGeneral disorders | 0/41 | 2/43 |
mITT population: all randomized subjects who received any amount of study medication and had a baseline and at least one postbaseline efficacy assessment
| Age, Continuous(years) | HepTcell | Placebo | Total |
|---|---|---|---|
| Mean | 50.95 ± 9.07 | 53.21 ± 8.08 | 52.11 ± 8.60 |
| Sex: Female, Male(Participants) | HepTcell | Placebo | Total |
|---|---|---|---|
| Female | 13 | 19 | 32 |
| Male | 28 | 24 | 52 |
| Race (NIH/OMB)(Participants) | HepTcell | Placebo | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 27 | 24 | 51 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 2 | 6 | 8 |
| White | 12 | 11 | 23 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 2 | 2 |
| Region of Enrollment(participants) | HepTcell | Placebo | Total |
|---|---|---|---|
| Canada | 6 | 8 | 14 |
| United States | 6 | 4 | 10 |
| United Kingdom | 1 | 4 | 5 |
| Germany | 0 | 1 | 1 |
| Spain | 9 | 11 | 20 |
| Thailand | 13 | 12 | 25 |
| Italy | 6 | 3 | 9 |
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Altimmune, Inc.