The present invention relates to novel bis-hydrazone derivatives of formula (I): wherein Ar1 and Ar2 may be identical or different and are each independently selected from the group consisting of groups of formula (II) and (III): Y1 and Z1 are independently CH or NRc+, provided that al least one of Y1 and Z1 is NRc+ and at least one of Y1 and Z1 is CH, and Ra, Rb, Rc, X2− and L as defined in the claims, or a hydrate or a solvate thereof. Compositions and kits comprising same are also described. Said bis-hydrazone derivatives of formula (I), compositions and kits are useful as drugs, in particular for treating or preventing cancers associated with the Epstein-Barr Virus.