Drug Watch

Drugs in Development for Hepatitis Delta:

Drug

Mechanism

Company

Clinical Trial Phase

Designations
Lonafarnib + Ritonavir
Prenylation Inhibitor
Eiger BioPharma, USA
Phase III D-LIVR studyCompleted; Lonafarnib + Ritonavir (LOWR6 study) - Phase III active, not recruiting        
FDA Breakthrough Therapy Designation
FDA Fast Track Designation
FDA Orphan Drug Designation
EMA Orphan Drug Designation
EMA PRIME 
Hepcludex (Formerly Myrcludex B)

 
Entry Inhibitor
Gilead Sciences, Inc.
Monotherapy: Approval by EMA & Biologics License Application filed with FDA - ongoing Phase III and Phase I trials
EMA PRIME
FDA Breakthrough Therapy Designation
FDA Orphan Drug Designation
Promising Innovative Medicine (PIM) Designation by British MHRA
BJT-778
Monoclonal Antibody
BlueJay Therapeutics
Phase IIA
EMA PRIME
REP 2139 - Mg (in combination with PEG-IFN and Tenofovir)
HBsAg Inhibitor
 Replicor, Canada
Compassionate Access Program available In France, Austria, Israel, Italy, and Turkey; Phase II clinical trial planned enrollment starting in France and USA, 2025

 
 N/A
Tobevibart + Elebsiran
SiRNA Immune Response Stimulator/HBsAg Inhibitor/Entry Inhibitor
Vir Biotechnology
Phase II (recruiting)
N/A
HH-003
Entry Inhibitor
Huahui Health
Phase IIb (recruiting)
N/A
Hepalatide
NTCP Target
Shanghai HEP Pharmaceuticals
Phase IIa (not yet recruiting)
N/A
ABI-6250 & Interferon Alpha Receptor Agonist
Small Molecule Entry Inhibitor
Assembly BioSciences
Pre-clinical
N/A
GI-18000
Immune Response  Stimulator
GlobeImmune, USA
Pre-clinical
 N/A

Chart Updated September 2024

Glossary: 

Terms: HBV = Hepatitis B Virus, CHB = Chronic Hepatitis B, HDV = Hepatitis Delta Virus, CHD = Chronic Hepatitis Delta, PEG-IFN = Pegylated Interferon, NTCP = Sodium/Taurocholate Co-transporting Polypeptide, HBsAg = Hepatitis B Surface Antigen, RNA = Ribonucleic Acid, SiRNA = Small Interfering RNA (a strand of synthetic RNA designed to specifically target a particular messenger RNA for destruction), FDA = U.S. Food and Drug Administration, EMA = European Medicines Agency, NIH = National Institutes of Health, British MHRA = Great Britain Medicines and Healthcare products Regulatory Agency

Interferon Alpha (IFN-α)

Pegylated interferon alpha has been used as an off-label treatment for CHD since 1980. Viral response rates typically range between 25 and 30% with this treatment. International guidelines recommend a treatment duration of 48 weeks. A high relapse rate and severe side effects with IFN-α make the study of alternative treatments timely and critical.

Lonafarnib + Ritonavir

Lonafarnib is a "prenylation inhibitor" and works by targeting the protein assembly process, which prevents new viruses from being created. Lonafarnib combined with ritonavir has shown promise in reducing hepatitis delta virus levels. Eiger Biopharmaceuticals has completed their Phase III D-LIVR clinical trial and topline data looks promising. The LOWR6 study, which is also investigating use of lonafarnib and ritonavir for treatment of hepatitis delta, is also currently in phase 3 trials (no longer recruiting). Lonafarnib has been granted Fast Track Designation and Breakthrough Therapy Designation by the FDA, PRIME Eligibility Designation by the EMA, and Orphan Drug Designation by the FDA and EMA. 

Hepcludex (formerly Myrcludex B)

Hepcludex (generic name bulevirtide) is an “entry inhibitor” that works by stopping the hepatitis delta virus from entering and infecting hepatocytes (liver cells), and breaking the cycle of reinfection. It has shown activity against the hepatitis B virus, and in July 2020 was approved by the European Commission for prescription in Europe, including Russia and the former Soviet Union, as the first effective hepatitis D drug in the world. In September 2020, it was launched in Germany, France, and Austria. In November 2021, Gilead Sciences filed a Biologics License Application with the FDA for approval of the drug in the United States. In November of 2022, this application was not approved, but this was related to concerns about the manufacture and delivery of the drug, rather than its clinical efficacy or safety, so hopes are high that the application will be re-submitted quickly and approved sometime in 2025. In April of 2023, the drug was approved for prescription in the wider European Union and the UK, and it has also since been approved for prescription in Switzerland. Studies have also shown promise for Hepcludex when combined with PEG-IFN in reducing hepatitis delta viral levels. Gilead Sciences, Inc. and other researchers are still conducting Phase III clinical trials, as well as Phase I and observational studies, to investigate the long-term effects of Hepcludex. These studies have shown the achievement of significant response for HDV at 48 weeks. This drug has been granted PRIME Eligibility by the EMA, Breakthrough Therapy and Orphan Drug Designation by the FDA, and Promising Innovative Medicine Designation by the British MHRA. 

BJT-778

BJT-778 is a monoclonal antibody against hepatitis B surface antigen (anti-HBsAg mAb). This drug neutralizes and clears hepatitis B and hepatitis D virions and depletes HBsAg-containing subviral particles, which may help to reconstitute an individual’s antiviral immunity and contribute to functional cure for chronic hepatitis B. The drug is in Phase IIa clinical trials and has recently received EMA PRIME designation. 

REP 2139-Mg

REP 2139-Mg is a "nucleic acid-based amphipathic polymer (NAP)" that works by preventing infected liver cells from releasing hepatitis B virus into healthy liver cells. It is being evaluated for use in combination with PEG-IFN and Tenofovir. A study indicated that this combination treatment lowered HBsAg levels, HBV DNA, and HDV RNA in some patients. Planning for Phase II trials for this drug in France and the United States is currently in progress and enrollment is planned for early 2025. A compassionate access program for use of this drug is currently available in Austria, France, Israel, Italy, and Turkey.

Tobevibart & Elebsiran (Vir-3434 & Vir-2218)

Elebsiran is an HBV-targeted SiRNA that has the potential to stimulate an effective immune response and demonstrate direct antiviral activity against HBV and HDV. Tobevibart is a monoclonal antibody that targets HBsAg and is designed to remove HBV and HDV virus from the blood and block the entry of these viruses into liver cells. A phase 2 study of both of these drugs is currently recruiting participants. 

HH-003

HH-003 is a novel entry inhibitor for HBV & HDV. It has the potential to become a new standard of care that offers functional cure, standalone or in combination with other therapeutics, for patients suffering from chronic HBV infection or HBV/HDV co-infection. A phase 2 study is currently recruiting participants.

Hepalatide

Hepalatide works by targeting NTCP (Sodium/Taurocholate Co-transporting Polypeptide). A Phase 2 study to evaluate efficacy in people living with chronic hepatitis D will soon be recruiting participants.

ABI-6250 & Interferon Alpha Receptor Agonist

These drugs are both in development by Assembly Biosciences and will work to prevent HDV and HBV from entering healthy liver cells by blocking receptor mechanisms on the healthy cells.

GI-18000

GI-18000 is an "immune response stimulator" that works by causing the host's T-cells to target and fight the infected liver cells.

For current clinical trials for hepatitis delta click here.

Updated September 2024