A real-world study of treatment sequences and second-line clinical outcomes in patients with HER2-positive metastatic breast cancer in US community practice.

PURPOSE: Standard-of-care for HER2-positive metastatic breast cancer (HER2 + mBC) patients consists of trastuzumab ± pertuzumab with chemotherapy in first-line (1L), and ado-trastuzumab emtansine (T-DM1) or the more recently approved trastuzumab deruxtecan (T-DXd) in second-line (2L). Contemporary data on treatment sequencing and real-world effectiveness is limited. This study aims to report 2L treatments and outcomes among HER2 + mBC patients in the United States (US). METHODS: HER2 + mBC patients initiating 2L treatment (index date) between January 2014 and February 2021 were identified from the Syapse Learning Health Network (LHN) database. Summary statistics for patient characteristics, treatment received, reasons for 2L discontinuation and time to 2L-clinical outcomes are reported. RESULTS: Of the 312 patients initiating 2L treatment, had a median age of 59 years (interquartile range [IQR], 50-66) at the start of 2L. The majority were white (69%) and had de novo mBC (62%). Top three 2L regimens included T-DM1 ± endocrine therapy (29%), trastuzumab/pertuzumab/taxane (10%) and T-DM1/trastuzumab (8%). Around 88% discontinued 2L and 63% received subsequent treatment. Median time-to-next-treatment was 10.6 months (95% CI, 8.8-13.3) and real-world progression-free-survival was 7.9 months (95% CI, 7.0-9.9). Among 274 patients who discontinued 2L, 47% discontinued due to progression and 17% because of intolerance/toxicity, respectively. CONCLUSION: This real-world US study showed that approximately two-thirds of 2L patients received subsequent therapy and disease progression was the most common reason for 2L discontinuation highlighting the need for timely 2L treatment with the most efficacious drug to allow patients to achieve longer treatment duration and delayed progression.

GASTric Cancer HER2 Re-Assessment Study 2 (GASTHER2): HER2 Re-assessment for Initially HER2-Negative Advanced Gastric Cancer Patients after Progression on First-Line Treatment.

PURPOSE: Heterogeneous human epidermal growth factor receptor 2 (HER2) overexpression in gastric cancer may lead to a misdiagnosis of HER2 status. Accurate assessment of HER2 status is essential for optimal treatment as novel HER2-directed agents are being investigated in various clinical settings. We evaluated the usefulness of HER2 re-assessment following progression on first-line treatment in initially HER2-negative advanced gastric cancer (AGC) patients. MATERIALS AND METHODS: We enrolled 177 patients with baseline HER2-negative AGC and performed HER2 re-assessment after progression on first-line treatment from February 2012 to June 2016 at Asan Medical Center, Seoul, Korea. The re-assessed HER2 status was analyzed with baseline HER2 status and clinical characteristics. RESULTS: The median age was 54 years (range, 24 to 80 years), and 123 patients (69.5%) were men. Seven patients (4.0%) were HER2-positive on the re-assessment. Patients with baseline HER2 negativity confirmed by a single test (n=100) had a higher HER2-positive re-assessment rate compared to those who had repeated baseline testing (n=77) (5.0% vs. 2.6%). Among the patients with single baseline HER2 testing, the rate was higher in patients with baseline HER2 immunohistochemistry (IHC) 1+ compared to those with IHC 0 (13.4% vs. 3.6%). CONCLUSION: Overall, 4.0% of patients with baseline HER2-negative AGC were HER2-positive on re-assessment, and the HER2-positive re-assessment rate was higher among patients who had a single test at baseline. HER2 re assessment may be considered for initially HER2-negative patients to determine their eligibility for HER2-directed therapy, particularly if their HER2 negativity was determined by a single test, especially if they had a single baseline HER2 IHC 1+ test.

Epidemiology of interstitial lung disease in patients with metastatic breast cancer at baseline and after treatment with HER2-directed therapy: a real-world data analysis.

PURPOSE: Using real-world data, interstitial lung disease (ILD) prevalence before and after HER2-directed therapy was estimated. Potential ILD risk factors in patients receiving HER2-directed therapy for metastatic breast cancer (mBC) were evaluated. METHODS: Adults with HER2-directed therapy for mBC initiated between September 25, 1998, and February 22, 2020 were, included. ILD was defined broadly as one or more of 64 lung conditions. Patients were followed until incident ILD, death, last contact, or study end. RESULTS: In total, 533 patients were identified with median age at mBC of 57, 51% had de novo mBC, 43% were ever smokers, 30% had lung metastases, 9% had thoracic radiation, 6% had chronic obstructive pulmonary disease, and 16% had prevalent ILD. ILD cumulative incidence at one year was 9% (95% CI 6%, 12%), with a median follow-up of 23 months. Smoking (HR 2.2, 95% CI 1.1, 4.8) and Black/African-American race (HR 3.4, 95% CI 1.6, 7.5) were significantly associated with ILD; HRs for preexisting lung conditions (HR 1.8, 95% CI 0.9, 3.8) and thoracic radiation (HR 2.3, 95% CI 0.8, 7.1) were not statistically significant. Prevalent ILD was associated with 13-fold greater occurrence of incident ILD. 85% of patients with prevalent or incident ILD were symptomatic. CONCLUSIONS: This real-world population of patients with mBC had a high prevalence of ILD prior to HER2-directed therapy, reflecting the multifactorial causation of interstitial lung changes. The cumulative incidence of ILD in patients receiving HER2-directed therapy for mBC augments prior reports. Symptomatic presentation suggests an opportunity for early intervention.

Adapted Physical Activity for Breast Cancer Patients Treated with Neoadjuvant Chemotherapy and Trastuzumab Against HER2 (APACAN2): A Protocol for a Feasibility Study.

BACKGROUND: The standard care for HER2-positive breast cancer is chemotherapy plus a HER2-directed therapy. This can lead to treatment-induced cardiotoxicity. On the other hand, the practice of physical activity is known to improve cardiac function; thus HER2-positive breast cancer patients could draw particular benefit from physical activity during treatment. However, at the time of diagnosis for breast cancer, the majority of patients are insufficiently active according to physical activity recommendations of World Health Organisation, and it is difficult to remain or become active during the treatment. There is a lack of data in the literature on the optimal program to propose to patients to encourage them to be active during treatment. The aim of our study is to assess the feasibility of a home-based physical activity program during neoadjuvant chemotherapy and trastuzumab for HER2-positive breast cancer. METHODS: The APACAN2 study is a single-centre, non-randomized interventional trial. Patients with HER2-positive breast cancer treated with anthracycline-based neoadjuvant chemotherapy and trastuzumab are eligible for enrolment. The supervised home-based physical activity program takes place during neoadjuvant chemotherapy (NACT). It combines aerobic and strengthening exercises. The primary endpoint is the proportion of patients reaching the international physical activity recommendations, i.e. 150 minutes of moderate-intensity activity per week at the end of NACT. The study started in April 2018 and seventy patients are expected to be recruited. DISCUSSION: In the literature, the majority of studies on practice of physical activity in breast cancer focus on adjuvant chemotherapy or on the period after the end of treatment. To the best of our knowledge, the APACAN2 study is the first to evaluate a home-based physical activity program during neoadjuvant chemotherapy for HER2-positive breast cancer. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov: NCT02963363, registered on July 11, 2016. Identifier with the French National Agency for the Safety of Medicines and Health Products N°ID RCB 2016-A01344-47, registered in August 2016. Protocol: version 8, 24 February 2021.

The management of HER2-positive early breast cancer: Current and future therapies.

Advances in human epidermal growth factor receptor 2 (HER2)-directed therapies have revolutionised the care of patients with HER2-positive breast cancer. While adjuvant trastuzumab in combination with chemotherapy has dramatically improved the prognosis for patients with early-stage disease, up to a quarter of patients will develop recurrent disease. The standard-of-care treatment paradigm has evolved with the introduction of newer HER2-directed therapies and increasing use of neoadjuvant systemic therapy, the latter providing us with important functional data to HER2-directed therapies and impacting subsequent adjuvant therapy decisions. However, these new strategies come at a cost of increased toxicity and economic burden, and only a subset of patients benefit from such approaches. Thus, ongoing work is required to identify predictive biomarkers of response, to de-escalate treatment in patients who may do just as well with less therapy, and new therapeutic approaches for patients who do not respond to currently used therapies. In this review, we will examine the current therapeutic landscape, summarise the latest evidence, and list the current treatment algorithms for early stage HER2-positive breast cancer.

Use of HER2-Directed Therapy in Metastatic Breast Cancer and How Community Physicians Collaborate to Improve Care.

The development of new HER2-directed therapies has resulted in a significant prolongation of survival for women with metastatic HER2-positive breast cancer. Discoveries in the laboratory inform clinical trials which are the basis for improving the standard of care and are also the backbone for quality improvement. Clinical trials can be completed more rapidly by expanding trial enrollment to community sites. In this article we review some of the challenges in treating metastatic breast cancer with HER2-directed therapies and our strategies for incorporating our community partners into the research network.

Pathological complete response of HER2-positive breast cancer to trastuzumab and chemotherapy can be predicted by HSD17B4 methylation.

Human epidermal growth factor (HER) 2-directed therapy is the standard treatment for HER2-positive breast cancer. Patients who achieved a pathological complete response (pCR) to the therapy are associated with excellent disease-free survival. However, few molecular markers are available to predict pCR. Here, we aimed to establish a DNA methylation marker to predict the response to trastuzumab and chemotherapy. A total of 67 patients were divided into screening (n = 21) and validation (n = 46) sets. Genome-wide DNA methylation analysis of the screening set identified eight genomic regions specifically methylated in patients with pCR. Among these, HSD17B4 encoding type 4 17ß-hydroxysteroid dehydrogenase was most significantly differentially methylated. The differential methylation was confirmed by pyrosequencing (P = 0.03), and a cutoff value was determined. This association was successfully validated in the validation set (P < 0.001), and patients with pCR were predicted with a high specificity (79%). Multivariate analysis, including tumor stage and hormone receptor status, showed that HSD17B4 methylation was an independent predictive factor (odds ratio: 10.0, 95% confidence interval 2.54-39.50, P = 0.001). Combination with ER status and HSD17B4 methylation improved the specificity up to 91%. Identification of HER2-positive breast cancer patients who would achieve pCR only by trastuzumab and chemotherapy may lead to surgery-free treatment for this group of breast cancer patients.

Neratinib, A Novel HER2-Targeted Tyrosine Kinase Inhibitor.

HER2 gene amplification and receptor overexpression is identified in 20% to 25% of human breast cancers. Use of targeted therapy for HER2-amplified breast cancer has led to improvements in disease-free and overall survival in this subset of patients. Neratinib is an oral pan HER inhibitor, that irreversibly inhibits the tyrosine kinase activity of epidermal growth factor receptor (EGFR or HER1), HER2, and HER4, which leads to reduced phosphorylation and activation of downstream signaling pathways. Neratinib is currently being tested in a number of clinical trials for its safety and efficacy in lung cancer, and colorectal, bladder, and breast cancers. In this review we discuss the available phase I, II, and III data for use of neratinib in the metastatic, adjuvant, neoadjuvant, and extended adjuvant settings along with the ongoing clinical trials of neratinib in breast cancer. We also elaborate on the side effect profile of this relatively new drug and provide guidelines for its use in clinical practice.

Buparlisib , an oral pan-PI3K inhibitor for the treatment of breast cancer.

INTRODUCTION: Deregulation of the phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) intracellular signaling pathway is common in breast cancer (BC) and has been found to be potentially implicated in resistance to endocrine and anti-HER2 therapies. Targeting the PI3K/Akt/mTOR pathway may remove this inhibition and restore sensitivity to these compounds. Buparlisib (BKM120) is a potent oral pan-class I PI3K inhibitor that is being extensively evaluated in multiple tumor types. AREAS COVERED: This review briefly summarizes the pharmacodynamics and pharmacokinetics of buparlisib, focusing on preclinical and clinical data in BC and on ongoing randomized trials. EXPERT OPINION: Overall, buparlisib is a safe and tolerable drug and, despite its peculiar toxicity profile, it is suitable for studies in combination with other anticancer agents in BC. Early-phase clinical trials in BC have provided evidence of antitumor activity. Several trials are being conducted in all the biological subsets of BC, including combinations with endocrine therapy, anti-HER2 agents, PARP-inhibitors and chemotherapy. While clinical results are eagerly awaited, biological material suitable for both genomic and non-genomic analyses is being collected. The authors expect an intense investigation of the potential biomarkers that explain response or resistance to buparlisib and inspire strategies to rationally explore the therapeutic potential of this drug.

HER story: the next chapter in HER-2-directed therapy for advanced breast cancer.

Untreated human epidermal growth factor receptor-2 (HER-2)-positive advanced breast cancer (ABC) is an aggressive disease, associated with a poor prognosis and short overall survival. HER-2-directed therapy prolongs both time to disease progression and overall survival when combined with chemotherapy and has become the standard of care for those with HER-2-positive breast cancer in the early and advanced settings. Despite the remarkable therapeutic impact HER-2-directed therapy has had on disease outcomes, some patients with HER-2-positive disease will have primary resistant disease and others will respond initially but will eventually have progression, underscoring the need for other novel therapeutic options. This article reviews recent phase III trial data and discusses a practical approach to sequencing of HER-2-directed therapy in patients with HER-2-positive ABC. The significant cumulative survival gains seen in these trials are slowly reshaping the landscape of HER-2-positive ABC outcomes.