Background: To evaluate the safety, pharmacokinetics (PKs), and pharmacodynamics of aflibercept, and to identify the recommended phase II dose (RP2D) of aflibercept in combination with pemetrexed and cisplatin.
Methods: Aflibercept was administered at escalating doses of 2, 4, or 6 mg kg(-1) in combination with fixed doses of pemetrexed (500 mg m(-2)) plus cisplatin (75 mg m(-2)) every 3 weeks. Blood samples were collected for PK analyses. Serum antiaflibercept antibodies were quantified to assess their impact on systemic aflibercept concentrations.
Results: Eighteen patients were enrolled. One patient dosed at 4 mg kg(-1) experienced grade 3 hypophosphatemia (dose-limiting toxicity; DLT), which prompted a cohort expansion. No further DLTs were observed in the 4 mg kg(-1) cohort or the 6 mg kg(-1) dose cohort. Most common adverse events (AEs) of all grades included (%): fatigue (89), anaemia (89), nausea (83), hyponatremia (78), and neutropenia (72). Grade ≥ 3 AEs consistent with anti-vascular endothelial growth factor therapy included (%): hypertension (22), pulmonary embolism (11), and deep vein thrombosis (6). Five patients (28%) experienced mild neurocognitive disturbance. No episodes of reversible posterior leukoencephalopathy syndrome (RPLS) were noted.
Conclusion: The results of this phase I study allowed further evaluation of the combination of aflibercept with pemetrexed and cisplatin in a phase II study. The RP2D of aflibercept was 6 mg kg(-1), to be administered intravenously every 3 weeks in combination with pemetrexed and cisplatin.