Poniard Announces Positive Incremental Efficacy and Safety Data From Ongoing Phase 2 Picoplatin Trial in Hormone-Refractory Prostate Cancer
- Updated Results Presented at 20th EORTC-NCI-AACR Symposium -
SOUTH SAN FRANCISCO, Calif. and GENEVA, October 22, 2008 /PRNewswire-FirstCall/ -- Poniard Pharmaceuticals, Inc. , a biopharmaceutical company focused on oncology, today announced positive incremental data from its ongoing Phase 2 clinical trial of picoplatin in combination with docetaxel and prednisone as first-line therapy for metastatic hormone-refractory prostate cancer (HRPC). The expanded and updated results continued to show that picoplatin can be safely administered with full-dose docetaxel and prednisone, the standard treatment for HRPC, with no neurotoxicity observed. In addition, reductions of prostate specific antigen levels (PSA) of at least 50 percent were achieved in 78 percent of evaluable patients. Normalized PSA levels were achieved in 26 percent of patients.
"These data are very encouraging as they suggest that picoplatin can be safely administered with full doses of docetaxel as first-line therapy in the treatment of hormone-refractory prostate cancer," said E. David Crawford, M.D., professor of surgery and radiation oncology, and head of the Section of Urologic Oncology at the and associate director of the Comprehensive Cancer Center in Denver. Dr. Crawford also is a member of Poniard's Clinical Advisory Board. "I believe these early Phase 2 results may potentially support a Phase 3 trial. A therapy with an improved safety and efficacy profile would be important for patients with advanced prostate cancer, who have a very poor prognosis and few effective treatment options."
The data were presented in a poster session (abstract # 211/poster #211) during the 20th EORTC-NCI-AACR Symposium on "Molecular Targets and Cancer" in Geneva, Switzerland. Picoplatin, the Company's lead product candidate, is a new generation platinum chemotherapy agent with the potential to become a platform product addressing multiple indications, combinations and formulations for the treatment of multiple solid tumor indications.
Phase 2 HRPC Trial Design and Preliminary Results
In the ongoing Phase 2 trial, the efficacy and safety of intravenous picoplatin (120 mg/m squared) administered every three weeks (21 days) in combination with full-dose docetaxel (75 mg/m squared) with daily prednisone (5 mg) as a first-line treatment are being evaluated in 30 patients with metastatic HRPC who have not received prior chemotherapy. PSA response (defined as a PSA reduction of at least 50 percent from baseline) is the primary endpoint; secondary endpoints include safety, response rate, time to progression and overall survival. The trial completed enrollment in December 2007.
Results presented at the Symposium showed a PSA response of at least 50 percent in 78 percent of the 27 evaluable patients and also showed that the combination of picoplatin and full-dose docetaxel can be safely administered. Manageable and reversible neutropenia were the main hematologic toxicities. In contrast to picoplatin monotherapy, thrombocytopenia was less severe and less frequent in combination with docetaxel. To date, no neurotoxicity has been observed in this study. These findings confirm and extend earlier Phase 2 results presented at the 44th Annual Meeting of the American Society of Clinical Oncology in May and results from the Phase 1 trial presented earlier this year.
"We are encouraged by the PSA decreases observed with picoplatin in combination with docetaxel to date and with the finding that picoplatin continues to be well tolerated in this Phase 2 proof-of-concept trial," said Robert De Jager, M.D., chief medical officer of Poniard. "Additional data from this ongoing study may support the advancement of picoplatin into a Phase 3 clinical trial for HRPC. Our growing body of safety and efficacy data also supports the potential for additional uses of picoplatin as a combination therapy in the treatment of non-small cell lung and ovarian cancers where platinum and taxane combinations are currently used."
Picoplatin has an improved safety profile relative to existing platinum-based cancer therapies and is designed to overcome platinum resistance associated with chemotherapy in solid tumors. It is being studied in multiple cancer indications, combinations and formulations. Picoplatin has been evaluated in more than 750 patients and has demonstrated anti-tumor activity in multiple indications with less severe kidney toxicity (nephrotoxicity) and nerve toxicity (neurotoxicity) than is commonly observed with other platinum chemotherapy drugs.
In addition to the ongoing Phase 2 clinical trial in HRPC, Poniard is evaluating intravenous picoplatin in an ongoing pivotal Phase 3 trial, known as SPEAR (Study of Picoplatin Efficacy After Relapse), in small cell lung cancer. This registration trial currently is being conducted under a Special Protocol Assessment (SPA) from the U.S. Food and Drug Administration and is evaluating overall survival as the primary endpoint. Picoplatin is also being evaluated in a Phase 2 clinical trial in patients with metastatic colorectal cancer. Oral picoplatin is being evaluated in a Phase 1 clinical trial in solid tumors. The oral formulation of picoplatin has the same active pharmaceutical ingredient as the intravenous formulation. Picoplatin has not been approved by any regulatory authority for use in humans.
Posted: October 2008