In the studies presented, researchers evaluated the activity of NKTR-102 versus irinotecan alone or administered in combination with 5-FU in nonclinical models of gastrointestinal cancers.  Anti-tumor activity was evaluated based on tumor growth delay (TGD) and regression responses.  In the first study, NKTR-102 was administered as a single-agent at doses of 60, 100, and 150 mg/kg resulted in maximum TGDs of 362 percent.  Regression response rates were dose-related and increased from 30-100 percent, with several animals remaining tumor free at the end-of-study at the 150 mg/kg dose level.  In contrast, the irinotecan monotherapy arm of this study was minimally active, yielding slight TGDs of 64 percent, with no regressions and no end-of-study survivors at a maximum-tolerated dose of 60 mg/kg.  In the second study, the combination of 100 mg/kg NKTR-102 with 50 mg/kg 5-FU was the most active regimen, yielding the maximum TGD of 232 percent, a 100-percent regression response rate and demonstrating superiority when compared to standard irinotecan in combination with 5-FU.  NKTR-102 was well tolerated as a monotherapy and when administered in combination with 5-FU in all of the studies.

These data were presented in a poster titled "Activity of NKTR-102 in nonclinical models of gastrointestinal cancers" (Abstract P-0025) at the ESMO Conference: 12th World Congress on Gastrointestinal Cancer in Barcelona, Spain on July 3-5, 2010.  The poster can be found on Nektar's website at nektar/product_pipeline/oncology_nktr-102.html.

SOURCE Nektar Therapeutics