Alacizumab is a humanized monoclonal antibody designed to target VEGFR2 (vascular endothelial growth factor receptor 2), a key receptor involved in angiogenesis—the formation of new blood vessels. By blocking VEGFR2, alacizumab inhibits signaling pathways that promote tumor vascularization, thereby restricting blood supply to tumors and limiting their growth and metastasis.

It has been investigated primarily in oncology, especially in the treatment of solid tumors such as pancreatic cancer, colorectal cancer, and non-small cell lung cancer. Alacizumab is often used in combination with chemotherapy or other targeted therapies to enhance anti-tumor efficacy. Its mechanism allows for normalization of tumor vasculature, which may improve delivery of chemotherapeutic agents to the tumor site.

In clinical trials, alacizumab showed potential in delaying disease progression and improving outcomes when used as part of combination regimens. However, development was discontinued in some indications due to limited efficacy or strategic decisions, highlighting the challenges in anti-angiogenic therapy. Despite this, it remains a reference antibody for research into VEGF pathway inhibition and tumor angiogenesis.