rhuMAb 2C4

Response by tumor measurement occurred if there was documented and confirmed CR or PR. Response was assessed by both the RECIST and by PSA levels measurement, based on measurable or non-measurable disease at baseline. Per RECIST, CR: disappearance of all target and non-target lesions and normalization of tumor marker level; PR: at least a 30 percent (%) decrease in the sum of the longest diameter of target lesions, taking as reference the baseline sum of longest diameter. A PSA response was defined as a PSA decline of greater than or equal to (≥) 50%, which had to be confirmed by a second PSA value at least 4 weeks later.

Per RECIST, disease progression was defined as at least a 20% increase in the sum of the longest diameter of target lesions, taking as reference the smallest sum of longest diameter recorded since the treatment started or the appearance of 1 or more new lesions, and/or unequivocal progression of existing non-target lesions.

A prior dose level was defined as an MTD if at a certain dose level, there were greater than or equal to (≥) 2 out of 6 participants who had Dose Limiting Toxicities (DLTs). If there were no DLTs or DLTs were seen in less than (\<) 2 participants in the highest dose level, that was considered as MTD. Participants received escalating doses of docetaxel and pertuzumab until DLTs were observed. DLTs were defined as any of the following: 1) Any non-hematological toxicity ≥ Grade 3 according to Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 except for fever, chills and flu-like symptoms, in spite of adequate toxicity management, 2) Grade 4 neutropenia lasting greater than (\>) 7 days, 3) Febrile neutropenia, 4) Thrombocytopenia Grade 4 or any thrombocytopenia requiring platelet transfusion or 5) Any subjectively intolerable toxicity felt by the investigator to be related to either one of the compounds.

MTD was defined as the highest tolerated dose combination of capecitabine (825 mg, 1000 mg or 1250 mg) and pertuzumab, without causing Dose Limiting Toxicities (DLTs). DLTs were defined as follows: 1) Any non-hematological toxicity greater than or equal to (≥) Grade 3 according to Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 except for fever, chills and flu-like symptoms, in spite of adequate toxicity management; 2) Grade 4 neutropenia lasting \> 7 days; 3) Febrile neutropenia; 4) Thrombocytopenia Grade 4 or any thrombocytopenia requiring platelet transfusion; 5) Any subjectively intolerable toxicity felt by the investigator to be related to either one of the compounds. Participants who withdrew from the study without completing the first treatment cycle for reasons other than DLT were not considered evaluable for DLT. MTD was measured in mg/m\^2.

For this protocol, an AE is defined any untoward medical occurrence (e.g., sign, symptom, disease, syndrome, intercurrent illness, abnormal laboratory finding) that emerges or worsens relative to pretreatment baseline during the treatment or post-treatment periods, regardless of the suspected cause. For this protocol an SAE was defined as any AE that occurred at any dose if: * It resulted in death (i.e., the AE caused or led to death), * It was life threatening, * It required or prolonged inpatient hospitalization, * It was disabling, * It resulted in a congenital anomaly/birth defect, * It may have jeopardized the participant or may have required medical or surgical intervention to prevent one of the outcomes listed above. The primary cause of death for all reported cases was disease progression, and all of the deaths occurred following study discontinuation, with one death occurring within 4 weeks of the last treatment day.

Incidence of DLTs defined as any Grade 3 or 4 major organ toxicity according to the National Cancer Institute Common Toxicity Criteria (NCI-CTC) Version 2 or any subjectively intolerable toxicity felt by the investigator to be related to rhuMAb 2C4. One participant in the 15.0 mg/kg dose group experienced a gastrointestinal hemorrhage on Day 16. This event was judged by the investigator to be related to study drug. The participant recovered in 3 days and continued to receive rhuMAb 2C4 beyond Cycle 2.This was the only DLT reported during the first two treatment cycles.