9-Amino camptothecin of formula (I) ##STR1## is prepared by: 1) reducing a compound of formula (II): ##STR2## wherein Hal is 10- or 12-halogen, in a single step to the 9-amino-camptothecin of formula (I) or, alternatively, 2a) reductively removing the Hal group from a compound of formula (II) so obtaining the compound of formula (III): ##STR3## and 2b) reducing the compound of formula (III) so obtaining the 9-amino camptothecin of formula (I); the said steps 1 and 2a) and, optionally, step 2b) each being carried out in the presence of a catalytic amount of a compound of formula PdL.sub.2 wherein L is acetate or halogen and, additionally, in the presence of an ammonium formate as a hydrogen source. The 9-amino camptothecin of formula (I) is useful as inhibitor of the enzyme topoisomerase I. It is useful in the treatment of cancers, in particular leukaemia, colon and rectal tumours.