The invention relates to a conjugate comprising (a) an amatoxin comprising (i) an amino acid 4 with a 6'-deoxy position; and (ii) an amino acid 8 with an S-deoxy position; (b) a target-binding moiety; and (c) optionally a linker linking said amatoxin and said target-binding moiety. The invention furthermore relates to a pharmaceutical composition comprising such conjugate.