A Phase 3 interventional study of Tobevibart and Elebsiran in Viral Hepatitis, sponsored by Vir Biotechnology, Inc.. Active, not recruiting at 39 sites in 10 countries. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-11-03.
Sponsored by Vir Biotechnology, Inc. · Phase 3, Interventional, and Treatment
This is a multicenter, open label, randomized Phase 3 clinical study to evaluate the efficacy and safety of the combination of tobevibart + elebsiran for the treatment of chronic hepatitis delta in comparison to delayed treatment.
343 studies on the registry are indexed under Hepatitis; 51 are open to participants now.
This study's enrollment of 124 is above the median of 85 across 245 interventional studies indexed under Hepatitis.
Browse Hepatitis studies →Vir Biotechnology, Inc. is the lead sponsor of 22 studies on the registry; 2 are open to participants now.
Of its 15 completed or terminated interventional studies of FDA-regulated products, 11 (73%) 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:
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.
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.
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.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
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.
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.
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.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Participants will receive treatment with tobevibart + elebsiran for 240 weeks.
Drug: Tobevibart · Drug: Elebsiran
Participants will receive tobevibart + elebsiran after an observational period for 240 weeks.
Drug: Tobevibart · Drug: Elebsiran
Tobevibart administered by subcutaneous injection
Also known as: VIR-3434
Elebsiran administered by subcutaneous injection
Also known as: VIR-2218
HDV RNA < Lower Limit of Quantification (LLOQ), Target Not Detected (TND) and alanine aminotransferase (ALT) normalization (ALT </= Upper Limit of Normal [ULN]) at Week 48 for Arm 1 vs at Week 12 for Arm 2
Time frame: Up to 48 weeks
Incidence of Treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs) through Week 12
Time frame: Up to 12 weeks
HDV RNA < LLOQ, TND at Week 48 for Arm 1 vs Week 12 for Arm 2
Time frame: Up to 48 weeks
Ran from Mar 2025 to primary completion in Sep 2026, 18 months.
Of 23 phase 3 interventional studies under Hepatitis, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 20 and three quarters within 38. This study's 18 months is below that.
Primary completion moved once since we started tracking on Sep 25, 2026: Dec 2026 → Sep 2026, on Nov 3, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
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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Studies of the drugs tested here: Tobevibart · Elebsiran