Edward C. O'rourke

Abstract 2766: Multicenter pharmacokinetic evaluation of ON 01910. Na, a novel broad-spectrum anticancer agent, in Phase I single agent clinical trials in patients with solid tumors

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Introduction: ON 01910. Na is an anti-cancer agent with demonstrated activity against both solid tumors and hematological cancers. The purpose of this research was to evaluate the effect of dose and administration schedule on ON 01910. Na pharmacokinetics (PK) in advanced, heavily pre-treated solid tumor patients. Methods: Data was collected in three Phase I protcols conducted in the US and in India covering a wide range of doses and intraveous infusion schedules: Protocol 1 (50-1375 mg/m2/day over 72 h); Protocol 2 (250 – 4450 mg/m2/day over 24 h) and Protocol 3 (2400-3200 mg over 2, 4 or 8 h). In several patients, pharmacokinetics were evaluated for more than 1 dosing cycle. Plasma samples were collected pre-dose and up to 72 hours post-infusion. ON 01910. Na plasma levels were determined by a validated LC/MS/MS method. Results: Ninety-five data sets from 81 patients were evaluated in this study. ON 01910. Na showed biphasic elimination from the plasma, regardless of dose and administration schedule. The functional half-life of ON 01910. Na, estimated from the initial decline of plasma levels following infusion termination, was less than 2 hours. This was confirmed in data from patients receiving prolonged infusions as ON. 01910. Na approached steady state levels within several hours after dose initiation. As noted in the table below, ON. 01910. Na clearance was lower at higher drug dosing rates. There were no differences in drug pharmacokinetics among the infusion schedules. Conclusion: The pharmacokinetics of ON 01910. Na is dose dependent. A continuous IV infusion would be recommended to treat patients because of its short plasma half-life and rapid clearance. Systemic drug exposure is not affected by type of dosing (flat dosing vs. BSA adjusted). No significant differences were noted between the PK profiles of patients in the US centers and the patients in the India centers. View this table: Effect of Dosing Rate on Clearance of ON 01910. Na Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2766.