Phase II study of NGR-hTNF, a selective vascular targeting agent (VTA), administered as single agent in patients (pts) with colorectal cancer (CRC) refractory to standard regimens

4088 Background: NGR-hTNF is a VTA exploiting a tumor-homing peptide (NGR) that selectively binds to an aminopeptidase N/CD13 overexpressed by tumor blood vessels. In preclinical models, NGR-hTNF showed antitumor activity both at low and at high doses. Methods: Pts with CRC resistant/refractory to standard treatments, including biological agents, were treated with low-dose NGR-hTNF given intravenously at 0.8 μg/m2 as 1-hour infusion every 3 weeks (q3w). This phase II trial had a 2-stage design with 16 and 27 pts to be enrolled after first and second stage, respectively. Progression-free survival (PFS) was the primary end-point with reassessment performed q6w. Results: From January to May 2007, 33 pts with radiologically- documented progressive disease after last therapy were evaluated over 111 cycles (range, 1–10). Pts characteristics were: median age: 65 years (range, 53 to 79); M/F 16/17; PS 0/1 26/7. Median number of prior regimens was 3 (range, 2 to 5). Eight pts (25%) were pre-treated with ≥4 lines a...