Geron Corporation announced the enrolment of the first patient in a clinical trial of its telomerase inhibitor drug, GRN163L, in locally recurrent or metastatic breast cancer.

The primary objective of the phase-I/II, dose escalation study is to determine the safety, maximum tolerated dose (MTD) and objective response rate of GRN163L when administered intravenously in combination with a paclitaxel/bevacizumab regimen in this patient population.

"We are excited to have enrolled the first patient in this study," said Kathy D Miller, MD, associate director for Clinical Research at the Indiana University Melvin and Bren Simon Cancer Center and lead investigator of the trial. "We have anticipated the clinical evaluation of this drug in breast cancer based on promising preclinical studies."

"This is an important milestone in the clinical development of our lead anti-cancer drug," said Fabio Benedetti, MD, Geron's chief medical officer, oncology. "Extending the clinical testing of GRN163L to breast cancer reflects the potentially broad and important role of telomerase in fighting cancer."

The current study is the fifth clinical trial of GRN163L. Studies are ongoing at 14 other US medical centers in patients with chronic lymphoproliferative diseases, multiple myeloma, non-small cell lung cancer, and other solid tumour malignancies administering GRN163L as either a single agent or in combination with conventional treatments.

Breast cancer is the most frequently diagnosed cancer in women, with an estimated incidence in the United States of more than 180,000 new cases and over 40,000 deaths this year. In addition, about 2,000 cases of breast cancer are expected to occur in men, accounting for 1% of all new breast cancers.

Telomerase is a critical and potentially broadly applicable tumour target. The enzyme is expressed in a wide range of malignant tumours, and its activity is essential for the indefinite replicative capacity of cancer cells that enables their malignant growth. Telomerase is absent or expressed only transiently at low levels in most normal adult tissues.

GRN163L is a short chain oligonucleotide that binds with very high affinity and specificity to the catalytic site of telomerase, resulting in competitive inhibition of enzyme activity. Proprietary manufacturing chemistry and 5' lipid chain were developed to improve the molecule's ability to penetrate cells and tissues.

Geron is a biopharmaceutical company that is developing first-in-class therapeutic products for the treatment of cancer and chronic degenerative diseases, including spinal cord injury, heart failure and diabetes. The products are based on our core expertise in telomerase and human embryonic stem cells.