Trastuzumab, tested only as a single agent, has been shown to achieve 7% response in heavily pretreated patients with AOC with 3+ and 2+ HER2 immunostaining by immunohistochemistry (IHC).

HER2 IHC 3+ staining was observed in 15 (4.7%) of the 320 tumor samples analyzed and HER2 IHC 2+ in 26 (8.1%; Table 1). Low HER2 expression (IHC 0 or 1+) was detected in the 279 (87.2% ...