Comparison of IgG and F(ab')2 fragments of bispecific anti-RCCxanti-DTIn-1 antibody for pretargeting purposes.

Purpose An effective pretargeting strategy was developed for renal cell carcinoma (RCC) based on a biologically produced bispecific monoclonal antibody: anti-RCC×anti-DTPA(In) (bsMAb: G250×DTIn-1). Tumour uptake of a 111In-labelled bivalent peptide after pretargeting with bsMAb G250×DTIn-1 was relatively high compared with that in other pretargeting systems using chemically coupled F(ab′)2 fragments. Here, we investigated the effect of the bsMAb form in the pretargeting strategy.