Hepatitis C Drug Bemnifosbuvir Shows Promise Against Hepatitis E Virus in Preclinical Studies
Key Insights
International researchers identified bemnifosbuvir, a nucleotide analogue already in hepatitis C (search) clinical trials, as an effective compound against hepatitis E virus (search) replication in laboratory studies.
The drug successfully prevented hepatitis E virus (search) replication in cell cultures while maintaining cell viability, and animal studies confirmed its efficacy in reducing viral activity and liver inflammation.
With hepatitis E (search) causing approximately 70,000 deaths annually and no approved vaccines or treatments available, bemnifosbuvir could potentially be repurposed for off-label use if hepatitis C (search) trials succeed.
An international research collaboration has identified bemnifosbuvir, a nucleotide analogue currently in clinical trials for hepatitis C (search), as a promising therapeutic candidate against hepatitis E virus (search) (HEV). The findings, published in the journal Gut on March 6, 2026, could address a critical unmet medical need for the approximately 70,000 people who die annually from hepatitis E (search) infections.
Drug Discovery Through Systematic Screening
The research team from Ruhr University Bochum (search), Heidelberg University Hospital, and Peking University (search) systematically screened a commercially available library of approximately 500 nucleotide/nucleoside analogues to identify compounds with anti-HEV activity. These synthetic molecules are designed to mimic the building blocks of genetic material in both human cells and viruses.
"These synthetically produced molecules are constructed similarly to the building blocks of our genetic material and likewise to that of viruses," explains Dr. Mara Klöhn from Ruhr University Bochum (search).
The researchers employed an innovative screening approach using a genetically modified hepatitis E virus (search) containing a fluorescent reporter gene. Cell cultures infected with this modified virus were treated with various candidate compounds, allowing researchers to monitor viral replication through fluorescence signals.
Promising Laboratory Results
Bemnifosbuvir demonstrated significant antiviral activity in the laboratory studies. "With bemnifosbuvir we were able to see that the virus no longer replicated, while the treated cells remained healthy," reports Jungen Hu from Heidelberg University.
The promising in vitro results were subsequently validated in animal studies conducted by the Chinese research team, which confirmed the drug's efficacy against HEV and its ability to reduce liver inflammation.
Clinical Development Pathway
The identification of bemnifosbuvir as an anti-HEV compound is particularly significant because the drug is already undergoing clinical evaluation for hepatitis C (search) treatment. This existing clinical development program could potentially accelerate its availability for hepatitis E (search) treatment.
"If the ongoing clinical trials of bemnifosbuvir against hepatitis C (search) are successful, the drug could soon also be available for off label use against hepatitis E (search)," say Dr. Viet Loan Dao Thi and Professor Eike Steinmann.
Addressing a Critical Medical Need
Hepatitis E virus (search) represents a major global health challenge as the leading cause of acute viral hepatitis. The disease was first documented during a major outbreak between 1955 and 1956, but intensive scientific research began only decades later.
While acute HEV infections typically resolve spontaneously in individuals with intact immune systems, the virus poses particular risks for vulnerable populations. In immunocompromised patients, including organ transplant recipients and individuals with HIV, HEV can progress to chronic infection. The virus also presents serious dangers for pregnant women.
Currently, no vaccine or specific antiviral therapy exists for hepatitis E (search), highlighting the urgent need for effective treatment options.
International Research Collaboration
This research represents a collaborative effort involving the Department of Molecular and Medical Virology at Ruhr University Bochum (search), the Dao Thi Lab at the Center for Integrative Infectious Disease Research (CIID) of Heidelberg University Hospital, and the Lin Wang Lab at Peking University (search) in China.
The study received comprehensive funding support from multiple international sources, including the National Key Research and Development Program of China, the Baden-Württemberg Stiftung's "Antiviral Therapies" research program, the German Research Foundation, the German Center for Infection Research, the Beijing Municipal Natural Science Foundation, and the National Natural Science Foundation of China.