Polaris Group Announces Positive Results for Phase 2 Study of ADI-PEG 20 in Malignant Pleural Mesothelioma

SAN DIEGO, Oct. 28, 2013 /PRNewswire/ -- Polaris Group announced today that positive results from a randomized Phase 2 trial of ADI-PEG 20, arginine deiminase formulated with polyethylene glycol, for the treatment of malignant pleural mesothelioma were presented at the World Conference on Lung Cancer in Sydney, Australia. There were 68 subjects randomized, 44 to ADI-PEG 20 plus best supportive care and 24 to best supportive care only. The target endpoint, enhanced progression free survival in those treated with ADI-PEG 20, was met with a hazard ratio of 0.53. In addition, partial responses, as determined by PET scanning, were observed in 46% of subjects treated with ADI-PEG 20.  The drug was also well tolerated. The study was led by Dr. Peter Szlosarek of Barts Cancer Center, Queen Mary University of London, and involved multiple sites in the United Kingdom.  Polaris Group is conducting clinical trials on ADI-PEG 20 for the treatment of several other indications, including hepatocellular carcinoma. The latter indication is already in a global Phase 3 study.

"We are pleased with the results of this randomized study of ADI-PEG 20. We plan to further investigate these results by performing a study of ADI-PEG 20 plus combination chemotherapy in mesothelioma," said John Bomalaski, M.D., Executive Vice President of Medical Affairs at Polaris Group. "ADI-PEG 20 is currently being evaluated in combination with cisplatin in melanoma and in combination with docetaxel in prostate cancer and non-small cell lung carcinoma. ADI-PEG 20 has a unique mechanism of action that we believe can complement the mechanisms of action of other agents in multiple studies to date. We are excited for such new studies to begin."

About ADI-PEG 20

ADI-PEG 20 is a biologic being developed by Polaris Group to treat cancers, especially those carrying a major metabolic defect that renders such cancer cells, unlike normal cells, unable to internally synthesize arginine. Because arginine is one of the 20 amino acids that are essential for protein synthesis and survival of cells, it is believed these cancer cells become dependent upon the external supply of arginine to survive and grow. ADI-PEG 20 is designed to systemically deplete the external supply of arginine, which causes arginine-dependent cancer cells to die while leaving the normal cells unharmed. Multiple cancers have been reported to have a high degree of arginine-dependency.

About Polaris Group

Polaris Group is a privately held biopharmaceutical company that specializes in the research and development of protein drugs to treat cancer and other debilitating diseases. The company's lead therapeutic, ADI-PEG 20, is currently being evaluated in a pivotal Phase 3 trial for hepatocellular carcinoma. Polaris Group is also investigating ADI-PEG 20 as a treatment for other cancers. In addition to the ADI-PEG 20 program, Polaris Group is researching and developing other biotherapeutic agents and is advancing a small molecule drug program that utilizes a rational structure-based approach to design novel compounds that inhibit the biological function of cancer-related protein targets.

For additional information please visit www.polarispharma.com

SOURCE Polaris Group