Trastuzumab retreatment after relapse on adjuvant trastuzumab therapy for human epidermal growth factor receptor 2-positive breast cancer: final results of the Retreatment after HErceptin Adjuvant trial.
OBJECTIVE
Trastuzumab, in combination with chemotherapy, is the standard of care for patients with early and metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The Retreatment after HErceptin Adjuvant trial assessed the efficacy and safety of trastuzumab plus a taxane as first-line treatment for patients with metastatic breast cancer (MBC) who had relapsed after adjuvant trastuzumab for HER2-positive early breast cancer.


METHODS
In total, 43 patients with HER2-positive MBC who had received previous adjuvant trastuzumab for ≥10 months, with a relapse-free interval of ≥6 months after the last adjuvant trastuzumab dose, were recruited. Eligible patients (n = 41) were assigned to receive trastuzumab, either weekly or every 3 weeks, in combination with docetaxel or paclitaxel until disease progression.


RESULTS
At the final analysis, with a median follow-up time of 40 months, a positive response was observed in 25/41 patients (61%; 95% confidence interval: 48.7-80.4%), stable disease in 7/41 (17.1%) and progressive disease in 6/41 (14.6%). Three patients had missing response assessments (one had no measurable lesions at baseline and two had no post-baseline tumour assessments). The median progression-free survival (PFS) was 8.0 months (95% confidence interval: 6-11 months) and the median overall survival was 25.0 months (16-33 months). No correlation was found between response rate, PFS or overall survival and the duration of adjuvant trastuzumab treatment, trastuzumab-free interval, relapse-free interval, hormone receptor status or type of pre-metastatic treatment. The most common adverse events (all grades) were alopecia (32%) and diarrhoea (32%). Six patients (14.6%) developed at least one serious adverse event. No congestive heart failure or any unexpected adverse events were reported.


CONCLUSIONS
Trastuzumab, in combination with a taxane, is an effective and well-tolerated first-line treatment for MBC in patients who relapse after trastuzumab-based adjuvant therapy.
National Institute of Oncology, Budapest, Hungary. Electronic address: lang@oncol.hu.
I
I
Láng
Andrew Love Cancer Centre, Geelong Hospital, Geelong, Victoria, Australia.
R
R
Bell
Cancer Institute and Hospital, CAMS, Beijing, China.
F Y
FY
Feng
National Oncology Institute, Panama, Republic of Panama.
R I
RI
Lopez
Medical University of Gdańsk, Gdańsk, Poland.
J
J
Jassem
N. N. Petrov Research Institute of Oncology, St Petersburg, Russia.
V
V
Semiglazov
F. Hoffmann-La Roche Ltd, Basel, Switzerland.
N
N
Al-Sakaff
F. Hoffmann-La Roche Ltd, Basel, Switzerland.
D
D
Heinzmann
R. S. McLaughlin Durham Regional Cancer Centre, Oshawa, Ontario, Canada.
J
J
Chang
D000328:Adult; D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D015331:Cohort Studies; D000077143:Docetaxel; D005260:Female; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D017239:Paclitaxel / Q000008:administration & dosage; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000378:metabolism*; D043823:Taxoids / Q000008:administration & dosage; D000068878:Trastuzumab
D061067:Antibodies, Monoclonal, Humanized; D000077143:Docetaxel; D017239:Paclitaxel; D018719:Erb-b2 Receptor Tyrosine Kinases; D043823:Taxoids; D000068878:Trastuzumab; C508053:ERBB2 protein, human
HER2-positive; metastatic breast cancer; retreatment; taxane; trastuzumab