Pharmacokinetic drug-drug interaction study of the angiopoietin-1/angiopoietin-2-inhibiting peptibody trebananib (AMG 386) and paclitaxel in patients with advanced solid tumors.

BACKGROUND: Trebananib is an anti-angiogenic peptibody under investigation in patients with advanced cancer. This study evaluated the pharmacokinetic (PK) drug-drug interaction of paclitaxel and trebananib. PATIENTS AND METHODS: Patients with advanced solid tumors received weekly 80 mg/m(2) intravenous (IV) paclitaxel (3 weeks on/1 week off) with weekly 15 mg/kg IV trebananib starting at Week 2. Blood samples for PK analysis were collected at Week 1 (paclitaxel alone), Week 6 (paclitaxel and trebananib), and Week 8 (trebananib alone). An absence of interaction was to be concluded if the 90 % confidence intervals (CI) for the differences in paclitaxel exposure fell within the 0.80-1.25 interval.
RESULTS: The primary study was conducted between 7/2012 and 10/2013. Thirty-five patients were enrolled and 34 received both treatments. Most patients were white (91 %) and female (59 %); mean age was 61 years. The most common tumor types were ovarian (32 %) and bladder (27 %), 71 % of patients had stage IV disease, and all had Eastern Cooperative Oncology Group (ECOG) scores of 0 or 1. PK parameter analysis was done on patients with evaluable PK data at both assessments (with and without concomitant therapy; n = 28). The geometric least squares mean (GLSM) ratio (90 % CI) of paclitaxel AUCinf with and without trebananib was 1.17 (1.10, 1.25). The GLSM ratio (90 % CI) of trebananib AUCtau,ss with and without paclitaxel was 0.92 (0.87, 0.97). The most common adverse events were fatigue, local edema, peripheral edema, and nausea.
CONCLUSIONS: This study showed no evidence of clinically meaningful PK interaction between paclitaxel and trebananib.