Safety and Targeting of Anti-hk2 Antibody in mCRPC

It is the intent to develop h11B6 as a therapeutic radiopharmaceutical for men with mCRPC. This Phase 0 study will be conducted to confirm the safety, estimate the mass amount, and confirm in vivo tumor targeting of the antibody. This study will use Indium-111 (111In) radiolabeled h11B6 in subjects with mCRPC to image known sites of disease and identify a favorable mass amount of antibody for satisfactory tumor targeting with minimal/no accumulation off-target. In cohort 1, In-111 labeled h11B6 will remain fixed at 2 mg, and additional h11B6 will be added in 2 sub-cohorts (8 mg and 18 mg respectively); up to 6 patients may be entered into a sub-cohort. Additional patients (up to 6) will be studied once the most favorable mass and imaging time point have been established, to establish targeting of antibody to known disease. This study will provide the dosimetric information crucial for Phase 1 therapy.