Plerixafor is a bicyclam molecule, which has been identified as a specific antagonist of CXCR4. It had originally been developed as an inhibitor of T-tropic human immunodeficiency virus, but later demonstrated to be an effective mobilizer of hematopoietic stem cells. Plerixafor was approved by FDA for autologous transplantation (in combination with granulocyte-colony stimulating factor) in patients with non-Hodgkin's lymphoma and multiple myeloma under the name Mozobil.