Aim: Targeted biocompatible nanoplatforms presenting multiple therapeutic functions have great potential for the treatment of cancer. Materials & methods: Multifunctional nanocomposites formed by polymeric nanoparticles (PNPs) containing two cytotoxic agents ? the drug alisertib and silver nanoparticles ? were synthesized. These PNPs have been conjugated with a chlorotoxin, an active targeting 36-amino acid-long peptide that specifically binds to MMP?2, a receptor overexpressed by brain cancer cells. Results: The individual and synergistic activity of these two cytotoxic agents against glioblastoma multiforme was tested both in vitro and in vivo. The induced cytotoxicity in a human glioblastoma?astrocytoma epithelial?like cell line (U87MG) was studied in vitro through a trypan blue exclusion test after 48 and 72 h of exposure. Subsequently, the PNPs? biodistribution in healthy animals and their effect on tumor reduction in tumor?bearing mice were studied using PNPs radiolabeled with 99mTc. Conclusion: Tumor reduction was achieved in vivo when using silver/alisertib@PNPs?chlorotoxin.