29 Jan 2014

The collaborative research team formed by The University of Hong Kong (HKU), Chinese Academy of Sciences, and Fudan University has made a breakthrough in discovering a novel drug candidate for the emerging Middle East respiratory syndrome coronavirus (MERS-CoV). The team discovered an “antiviral peptide” which is capable of inhibiting MERS-CoV from infecting the cells by its interaction with the stalk of the virus’ surface Spike protein responsible for virus entry into cells. The work is published online today (January 29, 2014) in the leading international scientific journal Nature Communications.

Research implications

MERS-CoV emerged in 2012 in the Middle East causing outbreaks of a SARS-like illness with a high case fatality rate of over 40%. The reports of person-to-person transmission of MERS-CoV through close contacts have raised global concern about its pandemic potential. Therefore, the development of drugs capable of curbing the spread of MERS-CoV is of great importance. This study finds a novel antiviral peptide that can be a potential drug candidate for treating MERS. The discovery is an important milestone in the treatment of MERS.

Study method and findings

The HKU research team has been actively studying and monitoring different types of coronaviruses since the SARS outbreak. Two of the coronaviruses previously discovered by the team in the bats in Hong Kong, namely, Tylonycteris bat coronavirus HKU4 and Pipistrellus bat coronavirus HKU5, were found to be closely related to MERS-CoV. As MERS-CoV and SARS-CoV share some similarities phylogenetically, the researchers used the convalescent sera of SARS patients to conduct antibody tests and found that cross-reactive anti-MERS-CoV antibodies existed in these serum samples because of a homologous region in the viruses’ surface proteins. Thus they suspected that “antiviral peptides” may also be able to inhibit MERS-CoV as in the case of SARS-CoV.

An “antiviral peptide” targeting MERS-CoV was later developed and tested jointly by the collaborative research team formed by HKU, Chinese Academy of Sciences, and Fudan University. The research team discovered that the “antiviral peptide” can effectively inhibit MERS-CoV from infecting cells in cell culture experiments. As it takes considerable time to develop “antiviral peptide” into a drug for market use, the HKU research team also tested the anti-MERS-CoV activity of other drugs which are already available in the market. They found that another two drugs used for treating other illnesses, namely mycophenolic acid (Mycophenolate mofetil) and interferon-β1b (Betaferon), also have significant activity against MERS-CoV in cell culture experiments. The three agents will be tested in animal models and clinical trials in future.

About MERS-CoV

MERS-CoV (formerly known as “human coronavirus EMC” or “novel coronavirus”) is a virus that may cause a “SARS-like” severe acute respiratory disease. Based on the limited information available, MERS-CoV may be transmitted from person-to-person through close contact. Currently there is no specific treatment for the infection. From April 2012 to January 27, 2014, the World Health Organisation has been informed of 180 confirmed cases, including 77 deaths.

About the research team

The research team is led by Professor Yuen Kwok-yung, Henry Fok Professor in Infectious Diseases, Chair Professor, Department of Microbiology, Li Ka Shing Faculty of Medicine, HKU, the Co-Director of the State Key Laboratory of Emerging Infectious Diseases and Academician of the Chinese Academy of Engineering, Professor Zhang Rongguang of the National Laboratory of Biomacromolecules of Chinese Academy of Sciences, and Professor Jiang Shibo of the Key Laboratory of Medical Molecular Virology of the Fudan University. Team members of the Department of Microbiology, Li Ka Shing Faculty of Medicine, HKU in this study also include Dr Chan Kwok-hung, Honorary Associate Professor, and Dr Jasper Chan Fuk-woo, Clinical Assistant Professor of Department of Microbiology.