HER2-positive Metastatic Breast Cancer Research Articles

Evolving treatments and outcomes in HER2-Positive metastatic breast cancer: Data from the GIM14/BIOMETA study

BackgroundTreatment for HER2-positive (+) metastatic breast cancer has improved in the last decade. We analyzed treatment changes over time and their impact on patients outcomes in a real-world dataset. MethodsData from 637 HER2+ patients with metastatic breast cancer enrolled in the multicenter Italian GIM14/BIOMETA study were retrieved. Progression-free survival (PFS) over time was evaluated according to the type of anti-HER2 therapy, disease onset (de novo vs. relapsing), metastatic site, and year of treatment (2000–2013 vs. 2014–2020). ResultsMedian follow-up was 64.4 months. Overall, for first-line therapies, mPFS was 16.5 vs 19.5 months for patients treated in 2000–2013 vs 2014–2020 (HR: 0.78, 95% CI:0.65–0.94, P = 0.008). mPFS improved over time in all patients except for those with brain metastasis. Interestingly mPFS was 17.4 vs13.4 months (HR, 1.49; 95% CI, 1.13–1.98, P = 0.005) in 2000–2013 and 24.4 vs 20.9 months (HR 1.04; 95% CI 0.78–1.40 p = 0.77) in 2014–2020 in pts without vs with liver metastases. For second line therapies, the overall median PFS was 9.6 months (95% CI, 8.31–10.97) and did not change over time. ConclusionMedian first-line PFS improved since 2014, mainly due to the introduction of pertuzumab. The outcome of patients with liver metastases appears to have improved in recent years. Patients with brain metastases had the worst PFS, which also did not improve over time.

Safety and efficacy study of oral metronomic capecitabine combined with pyrotinib in HER2-positive metastatic breast cancer: A phase II trial

PurposeTo analyze the safety and efficacy of orally administered metronomic capecitabine plus pyrotinib in HER2 positive metastatic breast cancer (MBC) patients, we conducted a prospective phase II study with a single-arm design. MethodsHER2 positive patients received oral metronomic capecitabine 500 mg three times a day and pyrotinib 400 mg per day. The primary endpoint was progression-free survival (PFS). Other endpoints included objective response rate (ORR), overall survival (OS), clinical benefit rate (CBR) and safety. ResultsThe study included 50 patients with MBC that was HER2-positive, while 1 patient was excluded due to nonstandard medication. The median PFS and OS was 11.9 months (95%CI 8.8–14.6) and 29.3 months (95%CI 24.4–34.8) respectively. ORR was 34.7%, and CBR was 81.6% with 2 CR (4.1%), 15 PR (30.6%) and 23 SD (46.9%). The mPFS in first- or second-line treatment was 12.2 months. The most frequent treatment-related adverse events included hand-foot syndrome, diarrhea, vomiting and nausea. Grade 3 adverse events occurred in 15(30.6%) patients, including hand-foot syndrome (12.2%), diarrhea (12.2%), vomiting (4.1%), and nausea (2.0%). 1 grade 4 adverse event of diarrhea (2.0%) was observed. ConclusionThe combination of metronomic capecitabine and pyrotinib is a promising regimen with competitive efficacy and improved tolerability in HER2 positive metastatic breast cancer patients.

Pretreatment 18F‐FDG uptake heterogeneity may predict treatment outcome of combined Trastuzumab and Pertuzumab therapy in patients with metastatic HER2 positive breast cancer

ObjectiveIntra-tumoral heterogeneity of 18F‐fluorodeoxyglucose (18F‐FDG) uptake has been proven to be a surrogate marker for predicting treatment outcome in various tumors. However, the value of intra-tumoral heterogeneity in metastatic Human epidermal growth factor receptor 2(HER2) positive breast cancer (MHBC) remains unknown. The aim of this study was to evaluate 18F‐FDG uptake heterogeneity to predict the treatment outcome of the dual target therapy with Trastuzumab and Pertuzumab(TP) in MHBC.MethodsThirty-two patients with MHBC who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) scan before TP were enrolled retrospectively. The region of interesting (ROI) of the lesions were drawn, and maximum standard uptake value (SUVmax), mean standard uptake value (SUVmean), total lesion glycolysis (TLG), metabolic tumor volume (MTV) and heterogeneity index (HI) were recorded. Correlation between PET/CT parameters and the treatment outcome was analyzed by Spearman Rank Test. The ability to predict prognosis were determined by time‐dependent survival receiver operating characteristic (ROC) analysis. And the survival analyses were then estimated by Kaplan‐Meier method and compared by log‐rank test.ResultsThe survival analysis showed that HI50% calculated by delineating the lesion with 50%SUVmax as threshold was a significant predictor of patients with MHBC treated by the treatment with TP. Patients with HI50% (≥ 1.571) had a significantly worse prognosis of progression free survival (PFS) (6.87 vs. Not Reach, p = 0.001). The area under curve (AUC), the sensitivity and the specificity were 0.88, 100% and 63.6% for PFS, respectively.Conclusion18F-FDG uptake heterogeneity may be useful for predicting the prognosis of MHBC patients treated by TP.

Twenty-Year Follow-Up of a Phase II Trial of Taxotere/Carboplatin/Herceptin in Patients With Metastatic HER2-Positive Breast Cancer.

As the implementation of trastuzumab, several studies have investigated new agents and regimens to treat human epidermal growth factor 2-positive (HER2+) metastatic breast cancer (MBC). However, long-term survival analyses from HER2-targeted therapies are lacking. This is a 20-year follow-up study of a phase II trial that evaluated the activity and safety of docetaxel in combination with carboplatin and trastuzumab (TCH) in patients with HER2+ MBC. This is a follow-up of a phase II, single-arm, open-label study. The primary objective was the activity from the combination of TCH in terms of response rate (RR). Secondary objectives included the activity from TCH in terms of response duration (RD), time to progression (TTP), overall survival (OS), and percent one-year survival. Between 11/1999 and 10/2002, 40 women were enrolled. Most patients (67.5%) had visceral metastasis on enrollment. After 2 decades and 3 months from first enrollment, there were 4 (10%) survivors (median follow-up of 3.2 years). The RR for complete response (CR) or partial response (PR) was 72.5%. The RR for CR was 42.5%. RD was 8 months. Median TTP was 10.8 months. Participants achieved a median OS of 39.8 months. Percent one-year survival was 92.5%. A subset of patients (10%) receiving trastuzumab in the metastatic setting have achieved long-term survival beyond 20 years.

Efficacy and Safety of Anti-HER2 Targeted Therapy for Metastatic HR-Positive and HER2-Positive Breast Cancer: A Bayesian Network Meta-Analysis.

Despite the development of HER2-targeted drugs, achieving favorable outcomes for patients with HR+/HER2+MBC remains challenging. This study utilized Bayesian Network Meta-analysis to compare the efficacy and safety of anti-HER2 combination regimens. The primary analysis focused on progression-free survival (PFS), while secondary analyses included objective response rate, overall survival (OS) and the incidence rate of grade 3/4 adverse events (AEs). A comprehensive search across seven databases identified 25 randomized controlled trials for inclusion in this meta-analysis. For patients eligible for endocrinotherapy, our findings revealed that dual-target combined endocrine therapy, such as Her2-mAb+Her2-mAb+Endo (HR = 0.38; 95%CrI: 0.16-0.88) and Her2-mAb+Her2-tki+Endo (HR = 0.45; 95%CrI: 0.23-0.89), significantly improved PFS compared to endocrine therapy alone. According to the surface under the cumulative ranking curves (SUCRAs), Her2-mAb+Her2-mAb+Endo and Her2-mAb+Her2-tki+Endo ranked highest in terms of PFS and OS, respectively. For patients unsuitable for endocrine therapy, anti-HER2 dual-target combined chemotherapy, such as Her2-mAb+Her2-mAb+Chem (HR = 0.76; 95%CrI: 0.6-0.96) and Her2-mAb+Her2-tki+Chem (HR = 0.48; 95%CrI: 0.29-0.81), demonstrated significant improvements in PFS compared to Her2-mAb+Chem. The results were the same when compared with Her2-tki+Chem. According to the SUCRAs, Her2-mAb+Her2-tki+Chem and Her2-mAb+Her2-mAb+Chem ranked highest for PFS and OS, respectively. Subgroup analyses consistently supported these overall findings, indicating that dual-target therapy was the optimal approach irrespective of treatment line.

Clinical Impact of New Treatment Strategies for HER2-Positive Metastatic Breast Cancer Patients with Resistance to Classical Anti-HER Therapies.

HER2-positive breast cancer accounts for 15-20% of all breast cancer cases. This subtype is characterized by an aggressive behavior and poor prognosis. Anti-HER2 therapies have considerably improved the natural course of the disease. Despite this, relapse still occurs in around 20% of patients due to primary or acquired treatment resistance, and metastasis remains an incurable disease. This article reviews the main mechanisms underlying resistance to anti-HER2 treatments, focusing on newer HER2-targeted therapies. The progress in anti-HER2 drugs includes the development of novel antibody-drug conjugates with improvements in the conjugation process and novel linkers and payloads. Moreover, trastuzumab deruxtecan has enhanced the efficacy of trastuzumab emtansine, and the new drug trastuzumab duocarmazine is currently undergoing clinical trials to assess its effect. The combination of anti-HER2 agents with other drugs is also being evaluated. The addition of immunotherapy checkpoint inhibitors shows some benefit in a subset of patients, indicating the need for useful biomarkers to properly stratify patients. Besides, CDK4/6 and tyrosine kinase inhibitors are also included in the design of new treatment strategies. Lapitinib, neratinib and tucatinib have been approved for HER2-positive metastasis patients, however clinical trials are currently ongoing to optimize combined strategies, to reduce toxicity, and to better define the useful setting. Clinical research should be strengthened along with the discovery and validation of new biomarkers, as well as a deeper understanding of drug resistance and action mechanisms.

Ex vivo dual gene therapy using human adipocytes secreting anti-HER2 antibody on HER2-positive xenograft tumor models.

Although targeted treatments against human epidermal growth factor receptor 2 (HER2) have improved survival in patients with metastatic HER2-positive breast cancer, long and repeated treatment is time-consuming and costly for patients. To reduce these burdens, we developed ex vivo gene-transduced adipocytes that secrete anti-HER2 antibodies and evaluated their anti-tumor effects. Ceiling culture-derived proliferative adipocytes (ccdPA) secreting anti-HER2 antibody against domain IV receptors: TRA-ccdPA, and domain II receptors: PER-ccdPA, were constructed using a plasmid lentivirus. Delivery of secreted antibody and its specific binding to HER2 breast cancer were evaluated in vitro and in vivo. To optimize antibody production from ccdPA, different conditions of ccdPA implantation were examined. Anti-tumor efficacy was evaluated in HER2-positive-cancer-inoculated nude mice. Anti-HER2 antibody against domain II was identified in supernatants from PER-ccdPAs. The optimal method to achieve the highest concentration of antibody in mouse sera was injecting differentiated ccdPA cells into the mammary fat pad. Antibody in supernatants from PER-ccdPAs bound to the surface of HER2-positive breast cancer cells similar to pertuzumab. Antibodies in mouse sera were delivered to HER2-positive breast cancer tumors and tumor necrosis was observed microscopically. One-time administration of combined TRA-ccdPAs and PER-ccdPAs produced antibody continuously in mouse sera, and anti-tumor effects were maintained for the duration of this study in xenograft models. Furthermore, combination therapy significantly suppressed tumor growth compared with a single administration. Ex vivo gene-transduced adipocytes might be useful for cell-based gene therapy. This system may be a platform for various antibody therapies.

Histologic heterogeneity predicts patient prognosis of HER2-positive metastatic breast cancer: A retrospective study based on SEER database.

Human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (MBC) is a subtype of breast cancer with a worse prognosis. Little is known about the relationship between histology and prognosis among different distant metastasis sites (DMS). Our aims were to explore the prognostic value of histologic subtypes in different DMS and screen out specific subtypes with particular DMS that need more attention in HER2+ MBC. HER2+ MBC patient data were obtained from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2014. Chi-squared tests were utilized to compare histologic subtypes in four DMS. The logistic regression analyses were used to control confounding factors. The log-rank tests were used to analyze the correlation of histologic subtype with disease-specific survival and overall survival. The survival data was analyzed using Kaplan-Meier methods. A total of 1174 HER2+ MBC patients were involved. First, the distribution of histological subtypes varied across metastatic sites, and the proportions of metastatic sites in different histological subtypes were also different. Furthermore, different histological subtypes within specific DMS showed divergent prognoses, and the different outcomes were shown by distinct DMS for specific histological subtypes. Among them, lobular carcinoma (ILC) subtypes showed the worst prognosis in bone metastasis, and lung metastasis predicted the worst prognosis in infiltration duct and lobular carcinoma (IDC-ILC) subtypes. After further consideration of hormone receptor (HR) status, the IDC-ILC subtype with liver metastasis in HR+/HER2+ MBC patients and the ILC subtype with bone metastasis in HR-/HER2+ MBC patients proved to be noteworthy. Histological subtypes are involved in determining the heterogeneity of HER2+ MBC patient prognosis, which is helpful to guide the prognosis prediction and monitoring of HER2+ breast cancer patients in clinics.

Clinical Guidance on the Monitoring and Management of Trastuzumab Deruxtecan (T-DXd)-Related Adverse Events: Insights from an Asia-Pacific Multidisciplinary Panel.

Trastuzumab deruxtecan (T-DXd)-an antibody-drug conjugate targeting the human epidermal growth factor receptor 2 (HER2)-improved outcomes of patients with HER2-positive and HER2-low metastatic breast cancer. Guidance on monitoring and managing T-DXd-related adverse events (AEs) is an emerging unmet need as translating clinical trial experience into real-world practice may be difficult due to practical and cultural considerations and differences in health care infrastructure. Thus, 13 experts including oncologists, pulmonologists and a radiologist from the Asia-Pacific region gathered to provide recommendations for T-DXd-related AE monitoring and management by using the latest evidence from the DESTINY-Breast trials, our own clinical trial experience and loco-regional health care considerations. While subgroup analysis of Asian (excluding Japanese) versus overall population in the DESTINY-Breast03 uncovered no major differences in the AE profile, we concluded that proactive monitoring and management are essential in maximising the benefits with T-DXd. As interstitial lung disease (ILD)/pneumonitis is a serious AE, patients should undergo regular computed tomography scans, but the frequency may have to account for the median time of ILD/pneumonitis onset and access. Trastuzumab deruxtecan appears to be a highly emetic regimen, and prophylaxis with serotonin receptor antagonists and dexamethasone (with or without neurokinin-1 receptor antagonist) should be considered. Health care professionals should be vigilant for treatable causes of fatigue, and patients should be encouraged to use support groups and practice low-intensity exercises. To increase treatment acceptance, patients should be made aware of alopecia risk prior to starting T-DXd. Detailed monitoring and management recommendations for T-DXd-related AEs are discussed further.

SDPS-46 CENTRAL NERVOUS SYSTEM (CNS)-RELATED MORTALITY IN PATIENTS WITH HER2-POSITIVE METASTATIC BREAST CANCER

Abstract BACKGROUND Approximately one third of patients with HER2-positive (+) metastatic breast cancer (MBC) develop brain metastases (BrM). In light of discordant control of extracranial metastases (ECM) versus BrM for standard-of-care antibody-based therapies for these patients, and the frequent use of radiation and surgical therapies particularly for patients with CNS-centric disease, we sought to determine the proportion of HER2+ MBC patients with BrM who suffered neurologic death in the CNS-only and intracranial-plus-extracranial metastasis settings, and the clinical risk factors of such. METHODS Clinicopathologic data for HER2+ MBC patients with BrM treated at an NCI-designated Comprehensive Cancer Center between August 2010 and April 2022 were collected, including disease burden at cancer presentation, the timing and pattern of BrM and ECM, and neurologic complications. CNS-related death was defined as any mortality caused by BrM, leptomeningeal progression, or BrM-associated complication. RESULTS 275 patients were included. 58/275 (21%) presented with CNS as only and first site of metastasis; the remaining (217/275, 79%) developed BrM synchronously with or subsequent to ECM. 125/275 (45%) had de novo MBC, and nearly all patients were treated with CNS therapies (254/275 [92%] received at least one radiation treatment and 88/275 [32%] underwent BrM resection). After a median follow-up of 2.5 years, 193/275 (70%) patients died, of whom 105 (54%) of CNS-related cause. The median OS was 3 years (95% CI=1.47-5.14) and 2 years (95% CI=1.74-2.34) for patients with CNS-only versus BrM concurrently/subsequent to ECM, respectively (p=0.059). The cumulative incidence of CNS-related death at 5 years was 40% (95%CI=33-46%). CONCLUSIONS Almost half of patients with HER2+ BrM suffered neurologic death. Patients with CNS-only disease had better OS than patients with synchronous/preceding ECM, suggesting that overall burden of disease affects mortality. With high rates of durable extracranial control with HER2-directed therapies, new strategies to prevent and eradicate CNS disease are urgent.

TIPS-10 FEASIBILITY OF A MULTI-MODALITY CENTRAL NERVOUS SYSTEM SCREENING EVALUATION IN HER2+ BREASTCANCER PATIENTS

Abstract BACKGROUND Breast cancer is the most common cancer in the world and the second most common to metastasize to the central nervous system (CNS). CNS-metastases are the most common type of brain tumor and have a rising incidence. They are associated with neurologic morbidity and mortality and remain a major clinical challenge. Survival withCNS-metastases is short with a median survival in the order of months. The incidence of CNS-metastases is 5.1% in breast cancer however true prevalence is not known; at autopsy this incidence ranges between 20-40%. One contributing factor towards the development of CNS-metastases in breast cancer is HER2-positivity. Between 25%-48% of patients with HER2-positive metastatic breast cancer develop CNS-metastases. Currently, routine CNS surveillance imaging is not recommended, however guidelines suggest having a low threshold for evaluation with imaging and/or cerebrospinal fluid (CSF) analysis because of the high rate of CNS-metastases. The clinical relevance of occult CNS-metastases, survival after identification of occult CNS-metastases and the importance of earlier initiation of CNS therapy are unknown. Existing treatment strategies for CNS-metastases rely on a combinatorial approach of chemotherapy, radiotherapy and/or surgery which typically affords limited disease control. This trial seeks to study if surveillance imaging and CSF analysis are feasible as early disease detection mechanisms. METHODS This is a two-cohort study to establish feasibility of multi-modality CNS surveillance. Patients with HER2+ metastatic breast cancer patients (with no known CNS-metastases) who are either Stage IV (Cohort A) or Stage II/III are eligible (Cohort B). On study, patients will undergo MRI Brain and CSF analysis at 6 monthly intervals. CSF analysis includes cytology, circulating tumor cells and cell-free DNA analysis. We plan to enroll 20 patients (10 onto each cohort). 1 of 20 patients have enrolled. This is the first multi-modality screening feasibility study for patients HER2-positive breast cancer.

Retrospective observational study of outcomes in HER2-positive metastatic breast cancer patients treated with trastuzumab emtansine in single center.

15 Background: Trastuzumab emtansine (T-DM1) was established as a standard second line treatment option for metastatic HER2 positive breast cancer (mBC). However, the EMILIA study did not include disease progression patients who received pertuzumab plus trastuzumab previously. After CLEOPATRA study, the dual blockade treatment was indicated for advanced breast cancer as first line treatment. In this study, we attempted to build the T-DM1 predictive model and to evaluate the association between dual blockade and T-DM1 for metastatic HER2-positive breast cancer. Methods: This retrospective cohort study was conducted in Taiwan. Consecutive patients with metastatic HER2-positive breast cancer who had received T-DM1 between January 2013 and December 2022 were enrolled. Those patients were divided to two groups based on strategy of trastuzumab only or dual-blockade as prior therapy. Demographic, clinical, and pre- and post-T-DM1 treatment characteristics were described. The swimmer plots were used to estimate time to treatment discontinuation (TTD) and overall survival (OS). Results: Of 32 patients treated with T-DM1, 12 (38%) had prior treatment with pertuzumab plus trastuzumab. The median age was 60 years. Most patients had visceral disease and 59% had two or more prior treatments for mBC before T-DM1 (range 1–8 lines). Most patients (63%) stopped T-DM1 due to disease progressed and followed by financial problem (22%). In dual-blockade group, median TTD with T-DM1 was 4.5 months; median OS from diagnosis day was 68.2 months (8 patients still alive in the end of study). In trastuzumab only group, median TTD with T-DM1 was 3.8 months; median OS from diagnosis day was 73.2 months (5 patients still alive in the end of study). In our swimmer plots we found a trend that the shorter interval between trastuzumab +/- pertuzumab and T-DM1 the longer TTD with T-DM1. Conclusions: Patients treated with T-DM1 in this study appeared to have more advanced disease than patients in clinical trials and were treated in later lines of therapy. We should prescribe T-DM1 once trastuzumab with or without pertuzumab failure for the longer TTD. The small patient number was a major limitation in our study. A multi-center analysis is needed and it will help us for treatment suggestion under the Taiwan’s National Health Insurance clinical practice.

Late-onset cardiotoxicity in patients with HER2-positive metastatic breast cancer receiving trastuzumab-based therapy.

Patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) typically receive long-term trastuzumab treatment for several years. The aim of our study is to identify the incidence and characterize late-onset cardiotoxicity in patients with HER2-positive MBC receiving trastuzumab-based therapy. We retrospectively reviewed charts of HER2-positive MBC patients who received >1 year of trastuzumab-based therapy at the Massachusetts General Hospital Cancer Center over three-year period. The primary endpoint was development of trastuzumab-induced cardiotoxicity (TIC). Secondary endpoints included time to TIC development, incidence/duration of trastuzumab interruption due to TIC, incidence of permanent discontinuation of trastuzumab due to TIC, clinic visit, or hospitalization due to TIC. Thirty-seven patients were included. Mean age was 56 years (range: 33-78 years, SD 9.5). Seven patients received prior doxorubicin and 14 patients received previous or concurrent breast irradiation. Mean duration of trastuzumab-based therapy was 57 months (range: 14-140 months, SD 39.3). Seven patients (18.9%) experienced TIC resulting in treatment interruption for two patients (28 and 78 days). The median time from starting trastuzumab therapy to TIC was 14 months (interquartile range: 11-29.5 months). The mean number of left ventricular ejection fraction (LVEF) assessment completed per year was 2.7 (range: 1.2-6.6, SD 1.1). Cardiotoxicity occurred in a minority of patients with HER2-positive MBC receiving trastuzumab-based therapy for more than one year. LVEF reductions to below the institutional lower limit of normal and therapy modifications were uncommon.

Fulvestrant with or without anti-HER2 therapy in patients in a postmenopausal hormonal state and with ER-positive HER2-positive advanced or metastatic breast cancer: A subgroup analysis of data from the Safari study (JBCRG-C06).

The role of endocrine therapy in the treatment of patients in a postmenopausal hormonal state and with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-positive advanced or metastatic breast cancer (AMBC) is unclear. We analyzed the data from 94 patients with ER-positive HER2-positive AMBC enrolled in the Safari study (UMIN000015168), a retrospective cohort study of 1072 ER-positive AMBC patients in a postmenopausal hormonal state who received fulvestrant 500 mg (F500): (1) to compare time to treatment failure (TTF) and overall survival (OS) by treatment group, and TTF by treatment line; (2) in patients who received endocrine therapy (including F500) or anti-HER2 therapy as initial systemic therapy before chemotherapy, to investigate relations between TTF for the first-line therapy or time to chemotherapy (TTC) and OS; (3) to investigate factors associated with OS. The TTF was longer in the patients treated with F500 as first- or second-line therapy (n = 20) than in those who received later-line F500 therapy (n = 74) (6.6 vs. 3.7 months; HR, 1.98; p = 0.014). In the 59 patients who received endocrine therapy or anti-HER2 therapy as initial systemic therapy before chemotherapy, those with TTC ≥3 years had longer median OS than those with TTC <3 years (10.5 vs. 5.9 years; HR, 0.32; p = 0.001). Longer TTC was associated with prolonged OS. In patients with ER-positive HER2-positive AMBC enrolled in the Safari study, TTF was longer in patients who received F500 as first- or second-line therapy. In patients who received chemotherapy-free initial systemic therapy, the prolonged OS in those with TTC ≥3 years suggests that this value may be a helpful cut-off for indicating clinical outcomes.

Cost-effectiveness model of trastuzumab deruxtecan as second-line treatment in HER2-positive unresectable and/or metastatic breast cancer in Finland

ObjectivesTrastuzumab deruxtecan (T-DXd) was recently recommended by the Committee for Medicinal Products for Human Use as a treatment for adult patients with unresectable or metastatic HER2-positive breast cancer, who had received a prior anti-HER2-based regimen. In our study, we evaluated the cost-effectiveness of T-DXd compared with ado-trastuzumab emtansine (T-DM1) for this indication in Finland.MethodsA three-state partitioned survival analysis model was developed with a payer’s perspective. Time to event data from the DESTINY-Breast03 (DB-03) trial were extrapolated over a lifetime horizon either directly—for progression-free survival and time to treatment discontinuation—or using an alternative approach utilizing long-term T-DM1 survival data and DB-03 data—for overall survival. Discount rates of 3% were applied for costs and effects. Inputs were sourced from the Medicinal Products Database from Kela, Helsinki University Hospital service price list, Finnish Medicines Agency assessments, clinical experts, and DB-03. Sensitivity analyses were performed to characterize and demonstrate parameter uncertainties in the model.ResultsTotal quality-adjusted life years (QALYs) and life years (LYs) gained for T-DXd compared with T-DM1 were 1.93 and 2.56, respectively. Incremental costs for T-DXd compared with T-DM1 were €106,800, resulting in an ICER of €55,360 per QALY gained and an ICER of €41,775 per LY gained. One-way sensitivity analysis showed the hazard ratio of T-DXd vs T-DM1 for OS was the most influential parameter. The probabilistic sensitivity analysis showed similar results to the base case.ConclusionsT-DXd is cost-effective based on surrogate WTP thresholds of €72,000 and €139,000 per QALY.

Metastatic HER2-Positive Breast Cancer: Is There an Optimal Sequence of Therapy?

Approximately 20% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2+), conferring a particularly aggressive subtype of the disease with an increased risk for the development of systemic and brain metastases. However, the advent of trastuzumab and more recently several other HER2-targeting novel therapies has led to significant improvements in the prognosis, making the diagnosis a "double-edged sword." The current standard first-line therapy for patients with HER2+ metastatic breast cancer (MBC) is a taxane combined with trastuzumab and pertuzumab. Trastuzumab deruxtecan should be used preferentially in the second line, with the only caveat being patients with CNS involvement where the tucatinib, capecitabine, and trastuzumab regimen could be considered. In the third line setting, given the survival benefits demonstrated with the tucatinib regimen in patients with and without CNS metastases, this is the preferred strategy. In the fourth line and beyond, there is no clear standard. Options include margetuximab in combination with chemotherapy, neratinib + capecitabine, or trastuzumab + chemotherapy. There are several novel therapies under investigation reporting promising results in the late-line setting. The treatment landscape of HER2-positive advanced disease is evolving constantly, with several active therapies being moved to the early-stage setting. Accordingly, it will be critical to identify biomarkers and mechanisms of resistance to optimize therapy selection and maximize patient outcomes and quality of life. Here, we provide an overview of the current and future management of HER2-positive advanced breast cancer and address the specific scenarios which may impact treatment selection including triple-positive breast cancer and the presence of brain metastases. Finally, we highlight promising novel treatments and ongoing trials that may impact future treatment sequencing.

Preclinical and clinical activity of DZD1516, a full blood–brain barrier-penetrant, highly selective HER2 inhibitor

BackgroundPatients with HER2-positive metastatic breast cancer (MBC) are at high risk of developing central nervous system (CNS) metastases. A potent and selective HER2 inhibitor with good blood–brain barrier (BBB) penetration is highly desirable.MethodsThe design and structure–activity relationship of DZD1516 was described. The potency and selectivity of DZD1516 were determined by enzymatic and cellular assays. The antitumor activity of DZD1516 monotherapy or in combination with HER2 antibody–drug conjugate was assessed in CNS and subcutaneous xenograft mouse models. A phase 1 first-in-human study evaluated the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of DZD1516 in patients with HER2+ MBC who relapsed from standard of care.ResultsDZD1516 showed good selectivity against HER2 over wild-type EGFR in vitro and potent antitumor activity in vivo. Twenty-three patients were enrolled and received DZD1516 monotherapy treatment across six dose levels (25–300 mg, twice daily). Dose-limiting toxicities were reported at 300 mg, and thus 250 mg was defined as the maximum tolerated dose. The most common adverse events included headache, vomiting, and hemoglobin decreased. No diarrhea or skin rash was observed at ≤ 250 mg. The mean Kp,uu,CSF was 2.1 for DZD1516 and 0.76 for its active metabolite DZ2678. With median seven lines of prior systemic therapy, the best antitumor efficacy in intracranial, extracranial and overall lesions was stable disease.ConclusionsDZD1516 provides positive proof of concept for an optimal HER2 inhibitor with high BBB penetration and HER2 selectivity. Further clinical evaluation of DZD1516 is warranted, with the RP2D being 250 mg BID.Clinicaltrials.gov identifier NCT04509596. Registered on August 12, 2020; Chinadrugtrial: CTR20202424 Registered on December 18, 2020.

Estimating the Product Lifecycle Value of Trastuzumab Based on Registry Data in Sweden.

Trastuzumab was introduced in Sweden in 2000 for treatment of HER2-positive metastatic breast cancer (MBC) and later expanded to early breast cancer (EBC). The potential value of this innovative therapy was explored in economic evaluations; however, the extent to which these benefits were realised remains unknown. This study aims to estimate the lifecycle value of trastuzumab by combining randomised trial data with Swedish routine-care data. Trastuzumab impact on costs and health outcomes was estimated with Markov models for MBC and EBC. Model inputs included progression/recurrence and breast cancer-related mortality data from international randomised clinical trials, and Sweden-specific non-breast cancer-related mortality, numbers treated, and costs and utilities based on data from National Registries and literature. Model predictions were validated by observed survival rates from the National Breast Cancer Registry. From 2000 to 2021, 3936 and 11,134 patients with HER2-positive MBC and EBC, respectively, were treated with trastuzumab, resulting in 25,844 life years and 13,436per quality-adjusted life years (QALY) gained. Cost per QALY gained was lower in EBC (Swedish krona [SEK]285,000/QALY) than MBC (SEK554,000/QALY). The net-monetary value delivered (excluding drug costs) was SEK 13.714 billion, and society retained 62% of this. The modelled survival in trastuzumab-treated patients with EBC matched closely with actually observed survival in registry data. Trastuzumab provided substantial population-level health benefits for patients and society, with favourable cost effectiveness in MBC and EBC. There is some uncertainty around the magnitude of these benefits, mainly due to missing data on health outcomes and number of treated patients with MBC.

건강보험청구자료를 이용한 HER2 양성 전이성 유방암 환자의 조기 사망에 따른 간접적 질병 부담 분석

The premature deaths caused by human epidermal growth factor receptor-2 protein (HER2) positive metastatic breast cancer (MBC) among working age groups result in significant socioeconomic losses. This study aims to quantify the socioeconomic burden of disease in female patients and provide evidence that can inform healthcare policy decisions. We identified deaths from HER2-positive MBC over the period from 2007 to 2021, using nationwide claims data of South Korea. Then, we estimated years of potential life lost (YPLL), years of potential productivity lost (YPPLL), and cost of productivity loss (CPL) to quantify socioeconomic burden of the disease. During the period from 2011 to 2020, a total of 3,576 patients died from HER2-positive MBC. The total YPLL over the period of 10 years from 2011 to 2020 was 128,605 years, corresponding to an average of approximately 36.0 years per deceased patient. The total YPPLL during the same period was 55,608 years, corresponding to an average of approximately 15.6 years per deceased patient. Additionally, total CPL of approximately 310 million won per deceased patient was incurred. All three disease burden indicators were highest among the age group of 40 to 54 years, which are individuals in their most productive time of life.

The аntitumor effect of 2-[3-(2-chloroethyl)-3-nitrosoureido]-1,3-propanediol (chlonisol) on the growth of spontaneous mammary tumors in HER-2/neu transgenic mice

Background. Current treatment of HER2-positive metastatic breast cancer (BC) is based on the use of anti-HER2 blockers as pathogenic drugs, as well as the search for the optimal combination of anticancer drugs with different mechanisms of action. The potential activity of chlonisol in HER2+ ВС is of great interesting. The aim of the study was to evaluate the antitumor effect of 2-[3-(2-chloroethyl)-3-nitrosouriedo]-1,3-propanediol (chlonisol) on the growth of spontaneous mammary tumors in HER-2/neu transgenic FVB/N mice. Material and Methods. A prospective study used 5-month-old female mice with HER2-positive mammary tumors. Of these animals, ten pairs with almost the same size of tumors were formed (respectively, for the control group and the chlonisol treatment group). Chlonisol was administered at a dose of 20 mg/kg intraperitoneally, once. The animals were followed up for 30 days. Results. In all ten pairs of mice, chlonisol showed a significant antitumor effect, up to a complete temporary regression of the tumor. When summing the comparative results of all ten pairs of animals, the inhibition of tumor growth (ITG) in the chlonisol treatment group was 90-97 % (p&lt;0.0001), and the area under the kinetic curve of tumor growth was 13.6 times less than in the control group (p&lt;0.0001), thus indicating a significant effect. Conclusion. Chlonisol has a high therapeutic activity by inhibiting the growth of spontaneous HER2-positive breast tumors in FVB/N mice.