Quest initiates dosing in Phase I clinical trial with SL052 Photodynamic Therapy in prostate cancer patients

May 12 2010

Quest PharmaTech Inc. (TSX-V: QPT) ("Quest" or the "Company"), a pharmaceutical company developing and commercializing products for the treatment of cancer, today announced the dosing of the first patient under the Company's recently initiated Phase I clinical trial with SL052 Photodynamic Therapy in prostate cancer patients. The study will evaluate the localization, safety, tolerability and preliminary treatment response of SL052 photodynamic therapy in 18 patients with localized prostate cancer.

SL052 is an injectible, synthetic derivative of a small molecular weight compound called Hypocrellin, which is isolated from a parasitic fungus that grows on bamboo trees in China. In Quest's Phase I trial, SL052 is inactive in a patient's body until activated by laser light of specific wavelength. Upon light activation, oxygen radicals are formed which are known to be toxic to tumor cells. This method of treatment is known as photodynamic therapy or PDT.

"SL052 photodynamic therapy is a promising treatment modality for prostate cancer because of its potential to minimize collateral damage compared to conventional treatment approaches," said Dr. Madi R. Madiyalakan, Quest's Chief Executive Officer. "In preclinical trials, SL052 photodynamic therapy demonstrated an impressive safety and efficacy profile. In this Phase I trial, our goal is to establish a safe and tolerable dosing regime of SL052 photodynamic therapy and monitor the patients for signals of efficacy."

The clinical trial is being conducted in two stages. In the first stage, up to six patients undergoing radical prostatectomy will be enrolled to study the prostate specific localization of SL052 after intra-arterial delivery. In the second stage, the safety and preliminary efficacy of SL052 PDT treatment with light dose escalation will be studied in 12 patients with localized prostate cancer. The treatment response will be monitored by MRI, prostate biopsy and changes in baseline PSA, which is an antigen associated with prostate disease progression.

This multi-disciplinary clinical trial is being conducted at the Princess Margaret and Sunnybrook Hospitals in Toronto and the University of Alberta Hospital in Edmonton. Dr. John Trachtenberg and Dr. Laurence Klotz, both Professors of Surgery at the University of Toronto, and Dr. Ronald Moore, Professor of Surgery and Oncology at the University of Alberta are the lead investigators. Dr. Brian Wilson, Professor of Medical Biophysics at the University of Toronto and interventional radiologists Dr. Richard Owen, Dr. John Kachura and Dr. Robyn Pugash are the co-investigators.

The American Cancer Society estimates there will be more than 192,000 new cases of prostate cancer in the U.S. in 2009, making it the third most prevalent form of cancer behind lung and breast cancer.

SOURCE Quest PharmaTech Inc.