Phase II trial of tesetaxel, an oral taxane, as second-line therapy for patients with advanced gastroesophageal cancer.

4077 Background: Tesetaxel is a novel, orally administered taxane. It is not a substrate for P-glycoprotein, and preclinical data suggest tesetaxel has potent antitumor activity that exceeds standard taxanes in human tumor xenografts while causing substantially less neuropathy. Tesetaxel is not associated with hypersensitivity, thus eliminating the need for premedication and extended observation. A prior study showed an overall major response rate (ORR) of 20% with tesetaxel used as 2nd-line therapy in patients (pts) with advanced gastric cancer. We previously showed that “flat” (i.e., non weight-based) dosing with tesetaxel was associated with excessive variability; therefore, we amended the final trial design to evaluate whether we could extend the prior observations in a confirmatory Phase 2 trial using the MTD. Methods: Eligibility included: adenocarcinoma of stomach/GE junction; 1 prior fluoropyrimidine-platinum regimen; ECOG PS 0-1; and adequate organ function. Tesetaxel was administered orally once...