Patient treatment has commenced in a Phase II clinical trial of SNS-595, Sunesis Pharmaceuticals' lead anti-cancer therapeutic, in patients with small cell lung cancer.

The trial is an open-label, multi-centre study designed to examine the safety and efficacy of SNS-595 as a second-line agent in patients with small cell lung cancer who have failed first-line therapy. SNS-595 is a first-in-class cell-cycle modulator that (in vitro) kills proliferating cancer cells by inducing apoptosis, or programmed cell death, as cells progress through the S phase of the cell cycle.

"Sunesis continues to demonstrate rapid progress in the advancement of multiple oncology products through development. This Phase II study in small cell lung cancer -- our second Phase II trial for SNS-595 -- is the fourth clinical trial we have initiated since last fall," said Daniel N. Swisher, President and Chief Executive Officer at Sunesis.

"Small cell lung cancer makes up approximately sixteen percent of lung cancers, and is characterized by rapid growth and spread, and commonly relapses within months of treatment," Daniel Adelman, Senior Vice President of Research and Development at Sunesis said adding, "First-line treatment for small cell lung cancer typically involves use of a platinum drug such as cisplatin in combination with a second agent, typically etoposide. While these chemotherapies are beneficial, most patients' disease recurs. We believe that SNS-595 has the potential to provide a meaningful benefit in second-line treatment as we have observed evidence of SNS-595's activity in platinum-resistant and etoposide-resistant xenograft models."

Patients with small cell lung cancer who have failed first-line treatment will be enrolled at multiple centers in the United States and Canada. Eligible patients will receive SNS-595 every three weeks at a dose and schedule identified in Sunesis' Phase I study of SNS-595 in patients with advanced solid malignancies. The trial design anticipates enrolling 80 patients -- 40 that are refractory and 40 that are sensitive.

According to the American Cancer Society, in 2006, approximately 160,000 people will die of lung cancer and approximately 174,000 new cases will be diagnosed in the US alone. Of these, approximately sixteen percent will be small cell lung cancer. Small cell lung cancer is estimated to affect approximately 34,000 patients in the US alone with 29,000 new cases diagnosed each year.