Cancer Immune Therapy Edited by G. Stuhler and P. Walden ...

was discovered during a clinical trial that small amounts of the LeY antigen are expressed
on the surface of endothelial cells and damage to these cells caused VLS. To
overcome such problems, new specific targets and new reagents against the cancer
antigens that will recognize only the tumor-associated molecules must be identified
and developed. The construction of large phage-display antibody libraries may result
in the isolation and characterization of new reagents with improved specificity and
affinity for cancer-targeted therapy.
17.9
Conclusions and Perspectives
Over the past decade, several second-generation recombinant immunotoxins with
improved properties have been developed and are currently being evaluated in clinical
trials. Several of these show clinical activity and promising results in phase I
trials [4, 128]. The outcome of these clinical trials demonstrates that the promising
preclinical results with these new agents can be translated into more substantial clinical
responses and that similar agents that target other cancer antigens merit further
clinical development. These accumulating results suggest that Fv±immunotoxins
merit further development as a new modality for targeted cancer treatment.
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17.9 Conclusions and Perspectives
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