Fourteen pharmacologic agents reported to have biological activities which are directly or indirectly antineoplastic, were assayed for their ability to inhibit the growth of a mouse neoplasia (M5076) and a rat mammary adenocarcinoma (13762) implanted beneath the renal capsule of the host. Ascorbic acid, cimetidine hydrochloride. Corynebacterium parvum, dimethylsulfoxide, naloxone hydrochloride, indomethacin, muramyl-dipeptide, Protein A from Staphylococcus aureus, theophylline, tilorone (analog R11, 877DA), tuftsin diacetate and sodium ibuprofen were completely inactive as antineoplastic agents for these 2 tumors. In fact, theophylline and dimethylsulfoxide seemed to enhance the formation of 13762 metastases. Blue tongue virus and polyinocinic-polycytidylic acid were marginally effective antineoplastic agents for 13762. Polyinocinic-polycytidylic acid was an excellent antineoplastic agent for M5076; this agent not only prevented the growth of M5076, it was oncolytic.
