ImmunoGen, Inc. (NASDAQ: IMGN) is a biotechnology company focused on the development of antibody-drug conjugate (ADC) therapeutics for the treatment of cancer. ImmunoGen was founded in 1981 and is headquartered in Waltham, Massachusetts. An ImmunoGen ADC contains a manufactured antibody that binds to a target found on cancer cells, with one of the companys potent cell-killing agents attached as a "payload". The antibody serves to deliver the cell-killing agent specifically to cancer cells bearing its target and the payload serves to kill these cells. In some cases, the antibody also has anticancer activity. The ADCs currently in the clinic with ImmunoGen technology employ one of the companys maytansinoid cell-killing agents, either DM1 or DM4, or one of the companys DNA-acting IGN payloads.