An experimental nanotherapy, IT-101, encapsulates a chemotherapy drug, camptothecin, inside a nanoparticle designed to circulate for an extended period in the bloodstream and to accumulate in tumors. In a human safety trial, evidence of the treatment’s efficacy was seen in some patients with advanced cancers. In the CT scans below, views of a patient’s midsection show a large lung tumor (top, circled) before treatment with IT-101 and after six months of treatment (bottom), when the tumor had shrunk considerably.