An Adverse Event (AE) is any unfavourable and unintended sign, symptoms, or diseases temporally associated with use of study drug, whether or not considered related to study drug. A serious adverse event (SAE) is an AE that results in death, initial or prolonged inpatient hospitalization, life-threatening, persistent or significant disability/incapacity, congenital anomaly/birth defect, or an important medical event. TEAEs and TESAEs are defined as AEs and SAEs present at baseline that worsened in intensity after administration of study drug, or events absent at baseline that emerged after administration of study drug, up to 60 days after the last study drug or until the participants started another anticancer therapy, whichever occurs first (approximately 8 years).

The AEs that occurred during Cycle 1 (Days 1 to 21) and were suspected of having a causal relationship to MEDI-573 and were \>= Grade 3 in severity were considered as DLTs.

The AEs that occurred during Cycle 1 (Days 1 to 21) and were suspected of having a causal relationship to MEDI-573 and were \>= Grade 3 in severity were considered as DLTs.

Progression-free survival (PFS) was defined as the time from the randomization until the first documentation of disease progression or death due to any cause, whichever occurred first. The PFS was censored on the date of the last tumor assessment documenting absence of tumor progression for participants who had no documented progression and were still alive prior to data cut-off, dropout, or the initiation of alternate anticancer treatment. Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as \>= 20% increase in the sum of diameters of target lesions and an absolute increase in sum of diameters of \>=5mm (compared to the previous minimum sum) or progression of non-target lesions or a new lesion.