Polaris Group Doses First Patient in Phase 1 Clinical Trial of Lead Therapeutic Candidate ADI-PEG 20 in Combination with Docetaxel in Advanced Solid Tumors with Emphasis on Prostate Cancer

SAN DIEGO, Jan. 10, 2012 /PRNewswire/ -- Polaris Group (Polaris) today announced that it has dosed the first patient in a Phase 1 clinical trial evaluating its lead cancer therapeutic, pegylated arginine deiminase (ADI-PEG 20), in combination with docetaxel in advanced solid tumors with emphasis on prostate cancer patients.

Patients with advanced solid tumors, including castration resistant prostate cancer, who are candidates for docetaxel, will be treated with a standard dose of docetaxel and increasing doses of ADI-PEG 20. Patients will receive weekly intramuscular injections of ADI-PEG 20 until disease progression.  The primary endpoints of the study are safety and efficacy, and secondary endpoints will include finding the maximum tolerated dose of ADI-PEG 20 with docetaxel.

Docetaxel is currently approved for the treatment of several malignancies, including breast cancer, non-small cell lung cancer, prostate cancer, gastric adenocarcinoma and squamous cell carcinoma of the head and neck.  Thus docetaxel, an anti-microtubule agent, is a widely used chemotherapeutic drug.

The rationale for the combination of ADI-PEG 20 plus docetaxel was previously reported by Polaris collaborators at the University of California at Davis Cancer Center, using both cell based assays, xenograft mouse models and PET imaging. In addition, they found a high percentage of prostate cancer tissue specimens require arginine. This institution will also lead this Phase 1 clinical study.

"We are pleased to begin the first human combination study of ADI-PEG 20," said John Bomalaski, M.D., executive vice president, medical affairs, of Polaris. "We believe ADI-PEG 20 is a promising cancer therapeutic not only as monotherapy but in combination therapy. ADI-PEG 20 as monotherapy is already in a Phase 3 global trial for patients with hepatocellular carcinoma, and in Phase 2 trials for patients with small cell lung carcinoma or mesothelioma. We look forward to continuing clinical development in these and in other areas to understand the full potential for this therapeutic."

Additional information about the trial can be found online at http://clinicaltrials.gov/ct2/show/NCT01497925?term=arginine+deiminase&rank=4

About Prostate Cancer

Prostate cancer is the second most common cancer found in American men after skin cancer, and is the second most common cause of cancer death in men, after lung cancer. In the United States, approximately 250,000 men will be diagnosed with prostate cancer this year, and approximately 34,000 deaths due to prostate cancer will occur. Prostate cancer will occur in 1 man in every 6 during his life.

About ADI-PEG 20

ADI-PEG 20 is a biologic being developed by Polaris to treat cancers carrying a major metabolic defect that renders them, unlike normal cells, unable to make arginine internally. Because arginine is one of the 20 amino acids that are essential for protein synthesis and survival of cells, these cancer cells become dependent upon the external supply of arginine to survive and grow. ADI-PEG 20 works by systemically depleting the external supply of arginine, which causes these 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. Phase 2 clinical trials of ADI-PEG 20 have yielded positive results in patients with hepatocellular carcinoma or metastatic melanoma, and Phase 2 trials for small cell lung cancer and mesothelioma are currently ongoing.

About Polaris Group

Polaris Group is a privately held multinational 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 is also investigating ADI-PEG 20 as a treatment for other arginine-dependent cancers, such as melanoma, leukemia, lymphoma, sarcoma and pancreatic cancer. In addition to the ADI-PEG 20 project, Polaris is researching and developing other biotherapeutic agents and has 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