Introduction: This study aimed to assess the safety and tolerability of the multitargeted tyrosine kinase inhibitor, vandetanib (V), in combination with two chemotherapeutic agents, oxaliplatin (O) and docetaxel (D) in advanced gastroesophageal (GE) cancer.
Methods: This was a Phase I study (NCT00732745) with a standard 3+3 dose escalation design. The primary aim was to determine the optimal dose of the combination of vandetanib and OD chemotherapy.
Results: Initial treatment for the first cohort consisted of oxaliplatin at 100 mg/m2 on day 1, docetaxel at 35 mg/m2 on days 1 and 8 and vandetanib 100 mg PO daily of 21-day treatment cycles. As dose limiting toxicity (DLT) was reached in 2 out of 3 patients in cohort 1 (one grade 3 and one grade 4 diarrhea with dehydration), 6 patients were treated then at dose level -1 (O 80 mg/m2 on day 1, D 30 mg/m2 on days 1 and 8, V 100 mg PO daily days 1-21) in which no further DLTs were observed. This dose was established as maximum tolerated dose and is the recommended phase 2 dose. 8 out of 9 enrolled patients had adenocarcinoma. At dose level 1, 1 of the 3 patients had a documented partial response and 2 patients had stable disease. At dose level -1, 1 of 6 patients achieved a complete response, 2 of 6 patients had stable disease, and 3 of 6 patients had progressive disease.
Conclusions: Vandetanib added to oxaliplatin and docetaxel showed manageable toxicity and limited activity in advanced GE cancer.