Enhanced activity of anticancer drugs in murine tumours by co-administration with 3-amino-pyrrolidine-2,5-dione-N-mustard derivative.

(R,S)3-(N,N-[bis-(2-chloroethyl)]-amino)-1-(2'-methoxyphenyl)- pyrrolidine-2,5-dione hydrochloride (I) has shown antitumor activity against P388 and L1210 leukaemias and Sarcoma 180 (ascites). The effect of (I), when co-administered with anticancer drugs, was studied in these murine tumours. Although co-administration of (I) with methotrexate showed a significant increase of the activity against P388 and L1210 leukaemias and Sarcoma 180 (ascites), co-administration of (I) with 5-fluorouracil, mitomycin C, adriamycin or vincristine did not exhibit any enhancing, synergistic or additive effect in the activity of these drugs.