Endpoints

The primary endpoint was MTD (phase I setting). The primary efficacy endpoint, (phase II setting) which was used to estimate sample size, was the objective response rate (ORR; defined as the proportion of patients with a complete response [CR] or partial response [PR]) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 [25]. Tumor assessment was undertaken every 2 cycles, with best responses being recorded. Responses were assessed by the investigator only.

Secondary endpoints included: disease control rate (DCR; defined as the proportion of patients with a CR, PR, or best response of stable disease [SD]), and progression-free survival (PFS) measured from the date of first infusion until the date of progression or death.