Ramucirumab, a fully human mAb to the transmembrane signaling tyrosine kinase VEGFR-2 for the potential treatment of cancer.

Angiogenesis is essential for tumor growth, invasion and metastasis, and is mediated, at least in part, by a large family of VEGF ligands and receptors. Ramucirumab, which is being developed by ImClone Systems Inc, is a fully human mAb that binds human VEGFR-2, thus blocking VEGF binding and inhibiting angiogenesis. Proof-of-concept preclinical studies with the mouse mAb DC-101 supported this hypothesis, and ramucirumab inhibited cell proliferation in vitro, as well as tumor progression in mouse xenograft models of human cancer. Ramucirumab was well tolerated on weekly and fortnightly schedules in phase I clinical trials in patients with advanced cancers; mechanism-related DLTs were hypertension and deep venous thrombosis. Stable disease was also observed in several patients treated on either schedule, and several patients on the weekly schedule exhibited partial responses. At the time of publication, ramucirumab was undergoing assessment in phase II trials as a monotherapy in hepatocellular, renal cell and ovarian carcinomas. Ramucirumab was also in phase II trials in combination with dacarbazine in melanoma, with mitoxantrone/prednisone in prostate cancer, with carboplatin/paclitaxel in NSCLC and with oxaliplatin/folinic acid/5-fluorouracil in colorectal cancer. A phase III trial in combination with docetaxel in breast cancer was also ongoing. Pending results from these trials, ramucirumab may be a useful addition to current antiangiogenic therapies. The results are awaited with interest.