A Phase 1 interventional study of HepB mAb19 and Sterile Saline in Hepatitis b Virus and Hepatitis B, sponsored by Rockefeller University. Active, not recruiting at 2 sites in United States. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-10-13.
Sponsored by Rockefeller University · Phase 1, Interventional, and Treatment
This is a first-in-human, placebo-controlled, single dose, dose-escalation phase 1 study to evaluate the safety, pharmacokinetics and antiviral activity of a highly potent neutralizing anti-HBV monoclonal antibody (mAb), HepB mAb19, which targets the S-protein in individuals with chronic hepatitis B (CHB) on nucleos(t)ide analog therapy (NRTI).
The study has a dose escalation design. In Groups 1-4, eligible participants will be randomized at a 3:1 ratio to receive a single intravenous infusion of HepB mAb19 or placebo (normal saline) at one of four increasing dose levels (1 mg/kg, 3 mg/kg, 10 mg/kg and 30 mg/kg). In Group 5 participants will receive HepB mAb19 at the maximum tolerated dose (MTD). Participants will be followed for 48 weeks after HepB mAb19 or placebo infusion.
1,045 studies on the registry are indexed under Hepatitis B; 139 are open to participants now.
This study's planned enrollment of 37 is below the median of 147 across 756 interventional studies indexed under Hepatitis B.
Browse Hepatitis B studies →Rockefeller University is the lead sponsor of 123 studies on the registry; 3 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 6 (43%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
- Clinical symptoms, imaging studies or liver histology suggestive of advanced fibrosis (exclude fibrosis grade 3 and 4 by FibroScan (Fibroscan®\< 9 kpa) within 12 months from entry or done at the pre-infusion visit.
Note: If FibroScan results from within 12 months are not available, imaging will be performed at the pre-infusion visit.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Single intravenous infusion of HepB mAb19, dosed at 1 mg/kg.
Biological: HepB mAb19
Single intravenous infusion of HepB mAb19, dosed at 3 mg/kg.
Biological: HepB mAb19
Single intravenous infusion of HepB mAb19, dosed at 10 mg/kg.
Biological: HepB mAb19
Single intravenous infusion of HepB mAb19, dosed at 30 mg/kg.
Biological: HepB mAb19
Single intravenous infusion of HepB mAb19, dosed at the MTD
Biological: HepB mAb19
Single intravenous infusion of placebo - normal saline, dosed at 1 mg/kg.
Other: Sterile Saline
Single intravenous infusion of placebo - normal saline, dosed at 3 mg/kg.
Other: Sterile Saline
Single intravenous infusion of placebo - normal saline, dosed at 10 mg/kg.
Other: Sterile Saline
Single intravenous infusion of placebo - normal saline, dosed at 30 mg/kg.
Other: Sterile Saline
HepB mAb19 is a human mAb of IgG1kappa isotype that specifically binds to the "a" determinant of the extracellular loop of the HBV surface antigen (HBsAg).
Placebo will be normal sterile saline (NaCl 0.9%).
Rate and severity of solicited adverse events that are Grade 2 or above within 2 weeks after administration.
The occurrence of solicited AEs will be assessed 2 weeks after IP administration.
Time frame: 2 weeks
Rate and severity of treatment-emerging unsolicited adverse events that are Grade 2 or above (including confirmed laboratory abnormalities) within 2, 12, 24 and 48 weeks after administration.
The occurrence of treatment-emerging AEs will be assessed after IP administration
Time frame: 48 weeks
Rate and severity of participants with serious adverse events (SAEs) throughout the study period that are considered related to investigational product and the duration of those SAEs.
The occurrence of SAEs will be assessed after IP administration
Time frame: 48 weeks
Rate and severity of participants with potential immune complex disease (ICD) throughout the study period following investigational product (IP) administration.
The occurrence of immune complex disease will be assessed after IP administration
Time frame: 48 weeks
Changes in AST within 2,12, 24 and 48 weeks after administration.
Changes in AST will be assessed after IP administration
Time frame: 48 weeks
Changes in ALT within 2,12, 24 and 48 weeks after administration
Changes in ALT will be assessed after IP administration
Time frame: 48 weeks
Changes in alkaline phosphatase within 2,12, 24 and 48 weeks after administration
Changes in alkaline phosphatase will be assessed after IP administration
Time frame: 48 weeks
Changes in bilirubin within 2,12, 24 and 48 weeks after administration
Changes in bilirubin will be assessed after IP administration
Time frame: 48 weeks
Changes in albumin within 2,12, 24 and 48 weeks after administration
Changes in albumin will be assessed after IP administration
Time frame: 48 weeks
Elimination half-life of HepB mAb19
Elimination half-life (t1/2) will be assessed after IP administration
Time frame: 48 weeks
Clearance (CL/F) of HepB mAb19
Clearance (CL/F) will be assessed after IP administration
Time frame: 48 weeks
Volume of Distribution (Vz/F) of HepB mAb19
Volume of Distribution (Vz/F) will be assessed after IP administration
Time frame: 48 weeks
Area under the curve (AUC) of HepB mAb19
Area under the curve (AUC) will be assessed after IP administration
Time frame: 48 weeks
Decay Curve of HepB mAb19
Decay Curve will be assessed after IP administration
Time frame: 48 weeks
Rate and severity of treatment-related adverse events during study follow up.
The occurrence of treatment-related AEs will be assessed after IP administration.
Time frame: 48 weeks
Rate of induced anti-HepB mAb19 antibodies in all study groups.
Occurrence of anti-HepB mAb19 antibodies will be assessed at baseline and after IP administration.
Time frame: 48 weeks
Change in quantitative HBsAg levels from baseline (day 0) at each scheduled follow up visit.
Serum HBsAg levels will be measured from baseline (day 0) until end of study follow up.
Time frame: 48 weeks
Detection of HBsAg by a qualitative assay at each scheduled follow up visit.
Qualitative measure of HBsAg will be performed from baseline (day 0) until end of study follow up.
Time frame: 48 weeks
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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