BACKGROUNDAntiangiogenesis is a promising field of cancer therapy. Endostar, a novel recombinant human endostatin, is one of the few approved drugs acting as angiogenesis inhibitors of cancer in China. However, there are few clinical studies about Endostar in gastrointestinal cancer. This pilot study aimed to evaluate the efficacy and safety of the combination of Endostar and chemotherapy in patients with metastatic colorectal and gastric cancers.

METHODSFrom March 2007 to October 2009, 23 patients were enrolled. Patients received Endostar intravenously at a dose of 15 mg daily from day 1 to 14 and day 1 to 7 when combined with 3- and 2-week chemotherapy regimens, respectively, which were determined according to patients' previous chemotherapy history. Treatment was repeated until disease progression, unacceptable toxicity or patients' refusal.

RESULTSSeven, six and ten patients received Endostar as first-, second- and third-line therapy, respectively. A total of 75 cycles were administered. Twenty-one patients were assessable for responses. The overall response rate and disease control rate were 19.0% and 47.6%, respectively. All the four partial responses were among patients receiving Endostar as first-line therapy, whose response rate was 57.1%. The median time to progression and overall survival were 2.6 months (95%CI, 2.0 - 3.2 months) and 10.3 months (95%CI, 3.9 - 16.7 months), respectively. Toxicity was tolerable, with grade 3-4 toxicities observed for leucopenia (30.4%), neutropenia (34.8%), thrombocytopenia (17.4%) and anemia (13.0%). Three patients (13.0%) encountered transient sinus bradycardia with spontaneous remission.

CONCLUSIONEndostar combined with chemotherapy is well-tolerated in patients with metastatic colorectal and gastric cancers, and it is relatively effective as a first-line therapy.