Site-directed chemotherapy with a drug bound to anti-idiotypic antibody to a lymphoma cell-surface IgM.

Xenogeneic antibodies against the cell-surface IgM of a B-cell lymphoma (38C-13) were coupled through a dextran bridge to the anti-neoplastic drug, daunomycin. The conjugate maintained both its antibody and its drug activity. The effectiveness of the conjugate was tested in vivo in mice challenged with the 38C-13 lymphoma. Drug conjugates of the idiotypic antibodies injected intraperitoneally 2 days after tumor transplantation almost completely inhibited tumor development. The controls, daunomycin-dextran-goat anti-DNP, free daunomycin, or the antibodies alone had no effect or only delayed the tumor development.