Cerulean Pharma Inc., of Cambridge, Mass., said preclinical data for CRLX101, a tumor-targeted nanoparticle-drug conjugate designed to concentrate in tumors and slowly release anticancer payload camptothecin inside tumor cells, showed that, in an ovarian cancer model, CRLX101 monotherapy was highly efficacious, and chronic low-dose CRLX101 in combinaton with Avastin (bevacizumab, Roche AG) reduced hypoxia-inducible factor-1 alpha up-regulation and resulted in synergistic efficacy, with minimal toxicity in mice.