PARP1 and neoplasm: In neuroblastoma 3D solid tumor models, comparison of the cytotoxic efficiencies of 125I-KX1 with other PARP1-targeted (211At-MM4) or non-PARP1-targeted (125I-MIBG) radiopharmaceuticals showed that 125I-KX1 was less effective compared to 211At-MM4 in terms of concentration, tumor dosage (350x lower per decay), and tumor-cell nuclei dosage (150x lower per decay) [51].