Celldex initiates accelerated approval study of Glembatumumab vedotin Celldex Therapeutics announced that it has launched a randomized study of Glembatumumab vedotin in patients with metastatic triple negative breast cancers that over-express glycoprotein NMB, or gpNMB). Glembatumumab vedotin is an antibody-drug conjugate that targets and binds to gpNMB, a specific protein that is expressed in breast cancer which promotes the migration, invasion and metastasis of the disease. It is also highly expressed in triple negative breast cancers where it is associated with increased risk of recurrence. Initial sites are now open to screen patients in the United States. Additional sites in the United States and in Canada and Australia will open in early 2014. The study is expected to include up to 100 sites and will enroll approximately 300 patients.