Phase II trial of gemcitabine/carboplatin (plus trastuzumab in HER2-positive disease) in patients with metastatic breast cancer.
BACKGROUND
Gemcitabine and carboplatin have significant preclinical synergy, and both provide synergistic antitumor activity in metastatic breast cancer (MBC) when used in combination with trastuzumab. The gemcitabine/ cisplatin combination is highly active in MBC with response rates (RRs) of approximately 50% in anthracycline- and taxane-pretreated patients and up to 80% in untreated subjects. This phase II trial studied the efficacy and safety of gemcitabine/carboplatin with or without trastuzumab in patients with MBC.


METHODS
Patients were stratified into 3 groups: group 1, HER2-positive; group 2, HER2-negative and taxane- naive/remote (no taxanes within past 2 years); and group 3, HER2-negative and previous taxane therapy. Included were women aged > or = 18 years, Eastern Cooperative Oncology Group performance status of 0-2, with Response Evaluation Criteria in Solid Tumors-defined measurable MBC; HER2-negative or HER2 (3+) by immunohistochemistry or fluorescence in situ hybridization positive. All cycles were repeated every 14 days. On day 1, gemcitabine 1500 mg/m2 over 30 minutes was administered followed by carboplatin area under the curve of 2.5. Group 1 also received trastuzumab 8 mg/kg on day 1 of each cycle followed by 4 mg/kg for every 2 weeks thereafter.


RESULTS
One hundred fifty patients were registered (50, 51, and 49 in groups 1, 2, and 3, respectively). The overall RRs were 64%, 27%, and 32%, respectively, with median time to progression of 7.2, 5.5, and 4.4 months, respectively. Overall, grade 3/4 toxicities included neutropenia (45%), leukopenia (17%), and thrombocytopenia (7%). Alopecia was infrequent: grade 1 (34%) and grade 2 (3%), and there was no significant cardiac toxicity.


CONCLUSIONS
Gemcitabine/carboplatin/trastuzumab is highly active in patients with HER2-positive MBC. Gemcitabine/carboplatin is active in patients with HER2-negative MBC independent of previous taxane therapy. Gemcitabine/carboplatin with or without trastuzumab administered every 2 weeks is associated with a low frequency of serious toxicity.
Loesch
David
D
US Oncology Research, Inc, Houston, TX, USA. david.loesch@usoncology.com
Asmar
Lina
L
McIntyre
Kristi
K
Doane
Lisa
L
Monticelli
Michael
M
Paul
Devchand
D
Vukelja
Svetislava
S
Orlando
Mauro
M
Vaughn
LaTrice G
LG
Zhan
Feng
F
Boehm
Kristi A
KA
O'Shaughnessy
Joyce A
JA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D016190:Carboplatin / Q000008:administration & dosage / Q000009:adverse effects; D003841:Deoxycytidine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000188:drug therapy* / Q000473:pathology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D000068878:Trastuzumab; D000093542:Gemcitabine
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D016190:Carboplatin; D003841:Deoxycytidine; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; D000093542:Gemcitabine; C508053:ERBB2 protein, human