Hera Trial: 2 Years Versus 1 Year of Trastuzumab After Adjuvant Chemotherapy in Women with Her2-Positive Early Breast Cancer at 8 Years of Median Follow up

Trends in neoadjuvant chemotherapy versus surgery-first in stage I HER2-positive breast cancer patients in the National Cancer DataBase (NCDB)

BACKGROUND

Neoadjuvant chemotherapy (NAC) is the standard of care for locally advanced HER2 + breast cancer (BC). Optimal sequencing of treatment (NAC vs. surgery first) is less clear cut in stage I (T1N0) HER2 + BC, where information from surgical pathology could impact adjuvant treatment decisions. Utilizing the NCDB, we evaluated the trend of NAC use compared to upfront surgery in patients with small HER2 + BC.

METHODS

We identified NCDB female patients diagnosed with T1 N0 HER2 + BC from 2010 through 2015. Prevalence ratios (PR) using multivariable robust Poisson regression models were calculated to measure the association between baseline characteristics and the receipt of NAC. Analysis of trends over time was denoted by annual percent change (APC) of NAC versus surgery upfront.

RESULTS

Of the 14,949 that received chemotherapy and anti-HER2 therapy during the study period, overall 1281 (8.6%) received NAC and 13,668 (91.4%) received adjuvant treatment. Patients receiving NAC increased annually from 4.2% in 2010 to 17.3% in 2015, with the most rapid increase occurring between years 2013 (8.5%) and 2014 (14.2%). The greatest increase was seen in patients with cT1c tumors with an APC of 37.8% over the study period (95% CI 29.0, 47.3%, p < 0.01), although a significant trend was likewise seen in patients with cT1a (APC = 26.1%,95% CI 1.59, 56.6%), and cT1b (APC = 27.4%, 95% CI 18.0, 37.7%) tumors. Predictors of neoadjuvant therapy receipt were age younger than 50 (PR = 1.69, 95% CI 1.52, 1.89), Mountain/Pacific area (PR = 1.24, 95% CI 1.05, 1.46), and estrogen receptor negativity (ER- PR + : PR = 2.01, 95% CI 1.51, 2.68; ER- PR- : PR = 1.49, 95% CI 1.32, 1.69).

CONCLUSIONS

Neoadjuvant therapy for T1 N0 HER2 + BC increased over the study period and was mostly due increased use in clinical T1c tumors. This may be consistent with secular change in Pertuzumab treatment following FDA approval in 2013.

Six versus 12 months' adjuvant trastuzumab in patients with HER2-positive early breast cancer: the PERSEPHONE non-inferiority RCT

BACKGROUND

The addition of adjuvant trastuzumab to chemotherapy has significantly improved outcomes for people with human epidermal growth factor receptor 2 (HER2)-positive, early, potentially curable breast cancer. Twelve months' trastuzumab, tested in registration trials, was adopted as standard adjuvant treatment in 2006. Subsequently, similar outcomes were demonstrated using 9 weeks of trastuzumab. Shorter durations were therefore tested for non-inferiority.

OBJECTIVES

To establish whether or not 6 months' adjuvant trastuzumab is non-inferior to 12 months' in the treatment of HER2-positive early breast cancer using a primary end point of 4-year disease-free survival.

DESIGN

This was a Phase III randomised controlled non-inferiority trial.

SETTING

The setting was 152 NHS hospitals.

PARTICIPANTS

A total of 4088 patients with HER2-positive early breast cancer who it was planned would receive both chemotherapy and trastuzumab took part.

INTERVENTION

Randomisation (1 : 1) to 6 months' or 12 months' trastuzumab treatment.

MAIN OUTCOMES

The primary end point was disease-free survival. The secondary end points were overall survival, cost-effectiveness and cardiac function during treatment with trastuzumab. Assuming a 4-year disease-free survival rate of 80% with 12 months' trastuzumab, 4000 patients were required to demonstrate non-inferiority of 6 months' trastuzumab (5% one-sided significance, 85% power), defining the non-inferiority limit as no worse than 3% below the standard arm. Costs and quality-adjusted life-years were estimated using a within-trial analysis and a lifetime decision-analytic model.

RESULTS

Between 4 October 2007 and 31 July 2015, 2045 patients were randomised to 12 months' trastuzumab and 2043 were randomised to 6 months' trastuzumab. Sixty-nine per cent of patients had ER-positive disease; 90% received anthracyclines (49% with taxanes; 41% without taxanes); 10% received taxanes without anthracyclines; 54% received trastuzumab sequentially after chemotherapy; and 85% received adjuvant chemotherapy (58% were node negative). At 6.1 years' median follow-up, with 389 (10%) deaths and 566 (14%) disease-free survival events, the 4-year disease-free survival rates for the 4088 patients were 89.5% (95% confidence interval 88.1% to 90.8%) in the 6-month group and 90.3% (95% confidence interval 88.9% to 91.5%) in the 12-month group (hazard ratio 1.10, 90% confidence interval 0.96 to 1.26; non-inferiority p = 0.01), demonstrating non-inferiority of 6 months' trastuzumab. Congruent results were found for overall survival (non-inferiority p = 0.0003) and landmark analyses 6 months from starting trastuzumab [non-inferiority p = 0.03 (disease-free-survival) and p = 0.006 (overall survival)]. Six months' trastuzumab resulted in fewer patients reporting adverse events of severe grade [365/1929 (19%) vs. 460/1935 (24%) for 12-month patients; p = 0.0003] or stopping early because of cardiotoxicity [61/1977 (3%) vs. 146/1941 (8%) for 12-month patients; p < 0.0001]. Health economic analysis showed that 6 months' trastuzumab resulted in significantly lower lifetime costs than and similar lifetime quality-adjusted life-years to 12 months' trastuzumab, and thus there is a high probability that 6 months' trastuzumab is cost-effective compared with 12 months' trastuzumab. Patient-reported experiences in the trial highlighted fatigue and aches and pains most frequently.

LIMITATIONS

The type of chemotherapy and timing of trastuzumab changed during the recruitment phase of the study as standard practice altered.

CONCLUSIONS

PERSEPHONE demonstrated that, in the treatment of HER2-positive early breast cancer, 6 months' adjuvant trastuzumab is non-inferior to 12 months'. Six months' treatment resulted in significantly less cardiac toxicity and fewer severe adverse events.

FUTURE WORK

Ongoing translational work investigates patient and tumour genetic determinants of toxicity, and trastuzumab efficacy. An individual patient data meta-analysis with PHARE and other trastuzumab duration trials is planned.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN52968807, EudraCT 2006-007018-39 and ClinicalTrials.gov NCT00712140.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 40. See the NIHR Journals Library website for further project information.

Human epidermal growth factor receptor family-targeted therapies in the treatment of HER2-overexpressing breast cancer

Breast cancer characterized by overexpression of human epidermal growth factor receptor 2 (HER2) has been associated with more aggressive disease progression and a poorer prognosis. Although an improved understanding of breast cancer pathogenesis and the role of HER2 signaling has resulted in significant survival improvements in the past 20 years, resistance to HER2-targeted therapy remains a concern. A number of strategies to prevent or overcome resistance to HER2-targeted therapy in breast cancer are being evaluated. This article provides a comprehensive review of (a) the role of HER2 signaling in breast cancer pathogenesis, (b) potential receptor and downstream therapeutic targets in breast cancer to overcome resistance to HER2-targeted therapy, and (c) clinical trials evaluating agents targeting one or more members of the HER family and/or downstream pathways for the treatment of breast cancer, with a focus on metastatic disease.