Bulevirtide is an antiviral medicine used to treat chronic (long-term) hepatitis delta virus (HDV) infection in adults with compensated liver disease (when the liver is damaged but is still able to work), when the presence of viral RNA (genetic material) has been confirmed by blood tests. Bulevirtide blocks the entry of HBV and HDV into hepatocytes by binding to and inactivating NTCP, a bile salt liver transporter serving as essential HBV/HDV entry receptor.