PRINCETON, N.J., June 14 Celator Pharmaceuticals today announced that new data from a preclinical leukemia study in mice demonstrate that its lead product, CPX-351 (Cytarabine:Daunorubicin) Liposome Injection, alone or in combination with clofarabine or azacytidine can improve treatment outcomes compared to the combination of either agent with the conventional (unencapsulated) cytarabine:daunorubicin regimen. The results were presented at the 15th Congress of the European Hematology Association in Barcelona, Spain, June 10-13, 2010 (Abstract #718(1)).
"As prior research has demonstrated, the challenge of combining cytarabine:daunorubicin with other anti-leukemic agents is that the dosing adjustments necessary to avoid unacceptable toxicities may compromise treatment efficacy," said Lawrence Mayer, PhD, president and head of research at Celator Pharmaceuticals. "The results from this model demonstrate the enhanced efficacy and wider therapeutic window of CPX-351 compared to the conventional cytarabine:daunorubicin regimen."
The study was conducted in a human leukemia xenograft model (CCRF-CEM mice). Tumor-bearing mice were treated with either clofarabine or azacytidine alone or with one of these agents in combination with CPX-351 or a conventional cytarabine:daunorubicin regimen. Maximum tolerated dose assessments were made for clofarabine and azacytidine singly, and in both combinations. The dose of CPX-351 had to be reduced by 50 percent when combined with either agent to avoid mortality or unacceptable weight loss. The dose of conventional cytarabine:daunorubicin had to be reduced by 50 percent when combined with clofarabine and by 75 percent when combined with azacytidine.
Prolongation of median survival relative to treatment with the individual agents, the principle efficacy outcome, was substantially greater for CPX-351 alone and for CPX-351 in combination with either agent. CPX-351 alone resulted in a greater median survival than conventional cytarabine:daunorubicin, single agent clofarabine or single agent azacytidine, or the combination of conventional cytarabine:daunorubicin with either clofarabine or azacytidine. CPX-351 in combination with either clofarabine or azacytidine produced the longest median survival.
"CPX-351 has potent anti-leukemia activity alone and in combination with other drugs in development for the treatment of leukemia," said Scott Jackson, chief executive officer of Celator Pharmaceuticals. "Based on the positive results generated with CPX-351 in patients with acute myeloid leukemia, the Company is evaluating the product's potential for the treatment of other hematologic malignancies."
CPX-351 (Cytarabine:Daunorubicin) Liposome Injection represents a new approach to developing combinations of drugs in which drug molar ratios with synergistic anti-tumor activity are encapsulated in a drug delivery vehicle in order to maintain the desired ratio following administration. CPX-351 has been granted orphan drug status by the U.S. Food & Drug Administration (FDA) for the treatment of acute myeloid leukemia (AML). Celator is currently conducting two randomized phase 2 studies with CPX-351 for the treatment of AML. The first randomized phase 2 study compares CPX-351 versus the standard "7+3" regimen of cytarabine:daunorubicin in patients 60 years of age up to and including 75 years of age with newly diagnosed AML. Celator recently reported topline data from this study. The primary efficacy endpoint of the study, the rate of patients achieving a complete remission with CPX-351 compared to "7+3," achieved statistical significance. In addition, the Company reported a reduction in the 30-day and 60-day mortality with CPX-351 versus the "7+3" regimen. The primary efficacy endpoint analysis, and additional results from this study, will be submitted to a major medical conference in 2010. The second randomized phase 2 study is comparing CPX-351 versus intensive salvage therapy in patients 18 years of age up to and including 65 years of age with AML in first relapse. Enrollment is expected to be completed in 2010. This study is supported by The Leukemia & Lymphoma Society.
About Celator Pharmaceuticals, Inc.
Celator Pharmaceuticals, Inc., with locations in Princeton, NJ, and Vancouver, BC, is a privately held pharmaceutical company developing new and more effective therapies to treat cancer. CombiPlex®, the company's proprietary drug ratio technology platform, represents a novel approach that identifies molar ratios of drugs that will deliver a synergistic benefit, and locks the desired ratio in a nano-scale drug delivery vehicle that maintains the ratio in patients with the goal of improving clinical outcomes. The company pipeline includes two phase 2 products; CPX-351 (a liposomal formulation of cytarabine:daunorubicin) for the treatment of acute myeloid leukemia and CPX-1 (a liposomal formulation of irinotecan:floxuridine) for the treatment of colorectal cancer; a preclinical stage compound, CPX-571 (a liposomal formulation of irinotecan:cisplatin); and multiple research programs, including the hydrophobic docetaxel prodrug nanoparticle (HDPN) formulation being studied by the National Cancer Institute's Nanotechnology Characterization Laboratory. Based on the applications of CombiPlex and the proprietary nanoparticle prodrug delivery platform, Celator is positioned to advance a broad pipeline of cancer therapies involving both previously approved and novel drug agents. For more information, please visit the company's website at www.celatorpharma.com. Information on ongoing trials is available at www.clinicaltrials.gov.
(1) EHA Abstract #718: Fan M, Mayer L, Udechukwu T, et al. Preclinical evaluation of CPX-351 liposome injection in combination with clofarabine and azacytidine. Poster presented June 11, 2010.
SOURCE Celator Pharmaceuticals, Inc.