CytRx Corporation announced that it has selected its next drug, designated DK049, for clinical development in 2016. DK049 was created using CytRx's novel LADR™ (Linker-Activated Drug Release) technology that allows the drug to bind to albumin in the body's bloodstream and controls its release at the site of the tumor. The LADR™ technology used with DK049 employs a two-stage linker that utilizes both pH sensitivity and acts enzymatically to allow release of its cytotoxic drug payload which extends the duration of exposure in tumors.

Prolonged inhibition of tumor growth has been demonstrated in human tumor xenograft models of pancreatic cancer, non-small cell lung cancer and ovarian cancer at doses that lack apparent toxicity. As an example of the LADR™ technology's capability, human ovarian tumor xenograft models received 85% less drug than a known chemotherapy comparator, yet at the end of the study, DK049-treated tumors were an average 13 times smaller than the chemotherapy-treated animals. These data have been submitted for presentation at the American Association of Cancer Research Annual Meeting in April 2016.

Additionally, CytRx has applied for patents for both its LADR™ technology and DK049 itself. CytRx's LADR™ technology has several advantages over current linkers: It allows prolonged drug exposure with accumulation at the site of the tumor. The linker reduces drug release in healthy cells.

The controlled release allows delivery of payloads that are 10-1,000 times more potent than standard chemotherapies. The LADR™ conjugates can evade traditional drug resistance mechanisms.