The invention concerns a cyclic dinucleotide compound of Formula (I):wherein Xis H or F； Xis H or F； at least one among Xand Xis a fluorine atom； Z is OH, OR, SH or SR, wherein: Ris Na or NH, or Ris an enzyme-labile group which provides OH or SHsuch as pivaloyloxymethyl； Band Bare bases chosen from Adenine, Hypoxanthine or Guanine, and Bis a different base than Band a pharmaceutically acceptable salt thereof. The invention also concerns pharmaceutical compositions comprising said cyclic dinucleotide, as well as their use in the treatment of a bacterial infection, a viral infection or a cancer.
