Use of berbamine or its analogue for preventing or treating RNA virus infection

A method of preventing or treating a subject suffering from a flavivirus infection caused by Japanese encephalitis virus, Zika virus, or Dengue virus by administering an effective amount of berbamine of Formula (I) or its analogue to the subject. A method of inhibiting the entry of such a flavivirus, an enterovirus and/or a lentivirus into host cells includes contacting the host cells with an effective amount of berbamine of Formula (I) or its analogue. The invention also provides a method of preventing or treating a subject suffering from a coronavirus, particularly SARS-CoV-2 or MERS-CoV, a method of inhibiting the entry of a coronavirus into host cells, as well as uses of berbamine or its analogue in the preparation of a medicament for preventing or treating a flavivirus infection, enterovirus infection, lentivirus infection or coronavirus infection.