Therapeutic landscape of advanced HER2-positive breast cancer in 2022

Overexpression of cytoplasmic poly(A)-binding protein 1 as a biomarker for the prognosis and selection of postoperative regimen in breast cancer

PURPOSE

The dysregulation of the cytoplasmic poly(A)-binding protein 1 (PABPC1) is involved in a variety of tumors but little is known about its role in human breast cancer. Therefore, the effect of PABPC1 in the prognosis and regimen selection in breast cancer patients was evaluated.

METHODS

A total of 791 cases of invasive breast cancer were included in this study, although only 416 were involved in subsequent analyses after the propensity score matching (PSM) test. PABPC1 expression was detected by immunohistochemistry. The relationship between PABPC1 expression and clinicopathological factors, postoperative regimens, and outcomes was determined.

RESULTS

In the total 791 cases, 583 cases were positive for PABPC1, but only 212 (26.8%) showed high PABPC1 expression (PABPC1-HE). The overall survival (OS) and disease-free survival (DFS) of PABPC1-HE patients after PSM were significantly worse than those in patients with PABPC1 low expression (PABPC1-LE), regardless of age, molecular type, tumor size, nodal status, or pStage. Postoperative chemotherapy (CT) increased the OS of PABPC1-HE patients but not that of PABPC1-LE patients. Among patients receiving endocrine therapy, those in the PABPC-LE group had an extended OS, while CT or chemoradiotherapy (CT/CRT) only significantly extended the OS time of PABPC-HE patients. CT/CRT did not significantly extend the survival of PABPC1-LE HER2-positive patients but extended the OS of PABPC1-HE HER2-positive patients. However, the OS of patients treated with CT/CRT + trastuzumab therapy was significantly longer than that of other patients under other therapies in the PABPC1-HE group, suggesting that PABPC1-HE might be sensitive to trastuzumab-based therapy. The multivariate analysis revealed that PABPC1-HE was an independent prognostic factor for both poor OS and DFS in breast cancer except luminal A type.

CONCLUSIONS

Our results revealed that PABPC1 might be considered as a biomarker to help in subtyping, as well as in the prognosis and regimen selection of breast cancer patients.

Trastuzumab Duocarmazine in Pretreated Human Epidermal Growth Factor Receptor 2-Positive Advanced or Metastatic Breast Cancer: An Open-Label, Randomized, Phase III Trial (TULIP)

PURPOSE

Human epidermal growth factor receptor 2 (HER2)-targeted therapy is standard of care for HER2-positive (HER2+) breast cancer, but most patients develop progressive disease with persistent HER2 expression. No definitive treatment guidance currently exists beyond second line. Trastuzumab duocarmazine (T-Duo) is a third-generation, HER2-targeted antibody-drug conjugate that demonstrated efficacy and acceptable safety in phase I studies of heavily pretreated patients with HER2+/HER2-low breast cancer.

METHODS

In this open-label, randomized, phase III trial, T-Duo was compared with physician's choice (PC) in patients with unresectable locally advanced/metastatic HER2+ breast cancer with progression during/after ≥2 HER2-targeted therapies or after trastuzumab emtansine (T-DM1). The primary endpoint was progression-free survival (PFS) by blinded independent central review.

RESULTS

In total, 437 patients were randomly assigned 2:1 to T-Duo (n = 291) or PC (n = 146). The median age was 56.0 years (range, 24-86); most patients (93.6%) had metastatic disease. The median time from diagnosis of metastatic disease to trial entry was 3.5 years; the median number of prior HER2-targeted therapies in metastatic setting was three. The median PFS was 7.0 months (95% CI, 5.4 to 7.2) with T-Duo versus 4.9 months (95% CI, 4.0 to 5.5; hazard ratio [HR], 0.64 [95% CI, 0.49 to 0.84]; P = .002) with PC. PFS benefit was maintained across most predefined subgroups. The median overall survival (first analysis) was 20.4 (T-Duo) versus 16.3 months (PC; HR, 0.83 [95% CI, 0.62 to 1.09]; P = .153). Objective response rate was 27.8% (T-Duo) versus 29.5% (PC); other efficacy end points-clinical benefit rate, duration of response, and reduction in target lesion measurement-tended to favor T-Duo. Grade ≥3 treatment-emergent adverse events occurred in 52.8% (T-Duo) versus 48.2% (PC).

CONCLUSION

Treatment with T-Duo was manageable, but tolerability was affected by prevalent ocular toxicity, leading to a higher discontinuation rate in the T-Duo arm. T-Duo significantly reduced the risk of progression in patients with advanced HER2+ breast cancer who have progressed during/after ≥2 HER2-targeted therapies or after T-DM1.

A phase Ia study of a novel anti-HER2 antibody-drug conjugate GQ1001 in patients with previously treated HER2 positive advanced solid tumors

BACKGROUND

A novel anti-human epidermal growth factor receptor 2 (HER2) antibody-drug conjugate (ADC) GQ1001 was assessed in patients with previously treated HER2 positive advanced solid tumors in a global multi-center phase Ia dose escalation trial.

METHODS

In this phase Ia trial, a modified 3 + 3 study design was adopted during dose escalation phase. Eligible patients were enrolled, and GQ1001 monotherapy was administered intravenously every 3 weeks. The starting dose was 1.2 mg/kg, followed by 2.4, 3.6, 4.8, 6.0, 7.2 and 8.4 mg/kg. Extra patients were enrolled into 6.0, 7.2, and 8.4 mg/kg cohorts as dose expansion phase. The primary endpoints were safety and to determine the maximum tolerated dose (MTD) based on dose limiting toxicities (DLTs). Pharmacokinetics and anti-tumor efficacy of GQ1001 were assessed. The plasma concentration of free DM1, the payload of GQ1001, was quantitated.

RESULTS

A total of 32 patients were enrolled, predominantly in breast (9), gastric or gastro-esophageal junction (9) and salivary gland cancer (4). Median number of prior-line of therapies was 3 (0-11) and 37.5% patients received ≥ 2 lines of anti-HER2 therapies. No DLT was observed during dose escalation. MTD was not reached and dose recommended for dose expansion (DRDE) was determined as 8.4 mg/kg. Grade ≥ 3 treatment-related adverse events rate was 28.1% (9/32) and platelet count decreased (4/32, 12.5%) was the most common one. No drug-related death was observed. Objective response rate and disease control rate of 15 evaluable patients in 7.2 mg/kg and 8.4 mg/kg cohorts were 40.0% (6/15) and 60.0% (9/15). Pharmacokinetics analysis showed low exposure and accumulation of free DM1 in circulation.

CONCLUSION

GQ1001 is well tolerated and shows promising efficacy in previously treated HER2-positive advanced solid tumors. DRDE was determined as 8.4 mg/kg for following trials. Trial registration NCT, NCT04450732, Registered 23 June 2020, https://clinicaltrials.gov/study/NCT04450732.

Targeting HER2 in breast cancer with brain metastases: A pharmacological point of view with special focus on the permeability of blood-brain barrier to targeted treatments

Understanding the capability of a drug to penetrate the blood-brain barrier (BBB) is an unmet medical need in patients with positive human epidermal growth factor receptor 2 (HER2 positive) and brain metastases. The National Comprehensive Cancer Network (NCCN) guidelines recommend the use of tyrosine kinase inhibitors (TKIs) lapatinib, neratinib, and tucatinib in co-administration with monoclonal antibodies or chemotherapy drugs and the antibody-drug conjugates (ADCs) trastuzumab-deruxtecan and trastuzumab-emtansine. Predicting the BBB permeability of these therapeutic agents is a pharmacological challenge due to the various factors involved in the barrier functions. In this review article, we discuss about the molecular and cellular features of the barriers located in the central nervous system and the pharmacological parameters found to be important in predicting BBB permeability in human normal brain, and in the presence of brain metastases. Finally, we reported the clinical outcomes and intracranial response of patients with HER2-positive breast cancer with brain metastases treated with targeted TKIs and ADCs.

Feasibility Study of Pyrrolitinib-Based Dual-Target Therapy for Neoadjuvant Treatment of HER2-Positive Breast Cancer Patients

Background

HER2-positive breast cancer is one of the high-risk subtypes of breast cancer for which dual-targeted therapy has become an important treatment option. However, for some patients, complete control of the disease is still not possible and additional treatment is required. Pyrrolitinib, an inhibitor of ALK and MET, has shown promising efficacy in breast cancer treatment. The aim of this study was to investigate the feasibility of adjuvant intensive therapy with pyrrolitinib in the treatment of HER2-positive breast cancer tumors.

Materials and Methods

Twenty-eight patients with HER2-positive breast cancer who were treated at the Breast Surgery Department of the Provincial Hospital of Weihai City, Shandong Province, China, between January 1, 2019, and January 1, 2023, were selected for this study. All of these patients received dual-targeted therapy with the addition of pyrrolitinib therapy adjuvant intensive therapy. We recorded data on the patients' basic information, pathological characteristics, treatment regimens, effects of treatment regimens, and adverse reactions, and statistically analyzed them.

Results

Of the 28 patients with HER2-positive breast cancer, all of them were added to adjuvant intensive therapy with pyrrolitinib. After examination of the samples during treatment, the breast cancer mass had been significantly reduced with the assistance of pyrrolitinib. In addition, no serious adverse reactions were found.

Conclusion

Adjuvant intensification of pyrrolitinib in the treatment of HER2-positive breast cancer tumors is feasible. The results of this study suggest that pyrrolitinib is a safe and effective therapeutic option that can significantly improve the outcome of HER2-positive breast cancer. More studies are needed to further validate this finding.

Radiotracer Innovations in Breast Cancer Imaging: A Review of Recent Progress

This review focuses on the pivotal role of radiotracers in breast cancer imaging, emphasizing their importance in accurate detection, staging, and treatment monitoring. Radiotracers, labeled with radioactive isotopes, are integral to various nuclear imaging techniques, including positron emission tomography (PET) and positron emission mammography (PEM). The most widely used radiotracer in breast cancer imaging is 18F-fluorodeoxyglucose (18F-FDG), which highlights areas of increased glucose metabolism, a hallmark of many cancer cells. This allows for the identification of primary tumors and metastatic sites and the assessment of tumor response to therapy. In addition to 18F-FDG, this review will explore newer radiotracers targeting specific receptors, such as estrogen receptors or HER2, which offer more personalized imaging options. These tracers provide valuable insights into the molecular characteristics of tumors, aiding in tailored treatment strategies. By integrating radiotracers into breast cancer management, clinicians can enhance early disease detection, monitor therapeutic efficacy, and guide interventions, ultimately improving patient outcomes. Ongoing research aimed at developing more specific and sensitive tracers will also be highlighted, underscoring their potential to advance precision medicine in breast cancer care.

Efficacy and safety of trastuzumab deruxtecan in treating human epidermal growth factor receptor 2-low/positive advanced breast cancer:A meta-analysis of randomized controlled trials

BACKGROUND

A novel antibody-drug conjugate, trastuzumab deruxtecan is a combination of a human epidermal growth factor receptor 2 (HER2)-targeting antibody and DNA topoisomerase I inhibitor used to treat HER2-low/positive advanced breast cancer. To determine its safety and efficacy in treating HER2-low/positive advanced breast cancer, we performed a meta-analysis of several randomized clinical trials (RCTs) including DESTINY-Breast02 (NCT03523585), DESTINY-Breast03 (NCT03529110), and DESTINY-Breast04 (NCT03734029).

METHODS

We searched PubMed, Embase, and the Cochrane Library for RCTs on the efficacy and safety of trastuzumab deruxtecan that were published before May 2023. The efficacy endpoints included median progressive-free survival (PFS), overall survival (OS), duration of response (DOR), overall response rate (ORR), and clinical benefit rate (CBR). The safety endpoints included treatment-related adverse events. Statistical analyses were performed using RevMan 5.4 software. To ensure transparency, this study was registered on the International Prospective Register of Systematic Reviews website (CRD42023414170).

RESULTS

Three RCTs involving 1689 patients were included. Compared with physician-recommended and conventional treatments, trastuzumab deruxtecan exhibited statistically significant improvements in PFS, ORR, and CBR. The median OS and DOR failed to be combined; however, the analyzed studies showed that they were longer. The incidence of adverse events was generally higher with trastuzumab deruxtecan than with physician-recommended or conventional treatments.

CONCLUSION

The results of this study suggest that trastuzumab deruxtecan is more effective in treating HER2-low/positive advanced breast cancer than physician-recommended or conventional treatments. However, trastuzumab deruxtecan-related adverse drug reactions should be closely monitored because of its higher incidence of adverse events.

Evaluation of Enhanced Cytotoxicity Effect of Repurposed Drug Simvastatin/Thymoquinone Combination against Breast Cancer Cell Line

INTRODUCTION

Repurposing of drugs for their anticancer potential is gaining a lot of importance in drug discovery.

AIMS

The present study aims to explore the potential of Simvastatin (SIM), a drug used in the treatment of high cholesterol, and Thymoquinone (Nigella Sativa) (THY) for its anti-cancer activity on breast cancer cell lines. Thymoquinone is reported to have many potential medicinal properties exhibiting antioxidant, antiinflammatory, anti-cancer, activities like inhibition of tissue growth and division.

METHODS

In this analysis, we explored the inhibitory effects of the combination of Simvastatin ad Thymoquinone on two breast cancer cell lines viz MCF-7 and MDA-MB-231 cells. The combined effect of Simvastatin and Thymoquinone on Cell viability, Colony formation, Cell migration, and orientation of more programmed cell death in vitro was studied. Cell cycle arrest in the G2/M phase was concomitant with the combined effect of SIM and THY persuading apoptosis and generating reactive oxygen species (ROS).

RESULTS

The cell cycle arrest with combined treatment was observed that only 1.8% and 1.1% cells gated in G2/M phase in MCF-7 & MDA-MB-231 cell. An increased apoptosis was observed when cells were treated in combination which was about 76.20% and 58.15% respectively for MCF-7 and MDA-MB-231 cells.

CONCLUSION

It was concluded that the combined effect of simvastatin and thymoquinone stimulates apoptosis in breast cancer cells.

Meta-analysis of the clinical efficacy and safety of T-DM1 in the treatment of HER2-positive breast cancer

ABSTRACT

This meta-analysis aims to comprehensively evaluate the efficacy and safety of T-DM1 in treating HER2-positive breast cancer, providing insights for clinical practice. We conducted a literature search in PubMed, Cochrane Library, and Embase databases up to September 2023, collecting randomized controlled trials and cohort studies on T-DM1 for HER2-positive breast cancer. Out of 316 initially retrieved articles, 12 studies meeting the quality and inclusion criteria were included after a rigorous screening process. We used RevMan 5.3 software for the meta-analysis, employing fixed or random-effect models. Odds ratios (RRs) and 95% confidence intervals (CIs) were calculated as effect size measures. We conducted sensitivity analyses and assessed publication bias to ensure the results' stability and reliability. In seven studies, T-DM1 treatment significantly prolonged OS in patients with HER2-positive breast cancer [hazard ratio (HR) = 0.70, 95% CI: 0.64-0.77, P < 0.01], and the effect was especially pronounced in patients with advanced disease (HR = 0.64, 95% CI: 0.54-0.76, P < 0.001). Analysis of pCR rates did not show a significant difference (OR = 0.91, 95% CI: 0.48-1.73, P = 0.77). In five studies, ORR improved, but the difference between the two groups was not significant (OR = 1.16, 95% CI: 0.66-2.05, P = 0.61). Analysis of progression-free survival (PFS) showed a significant improvement in the experimental group relative to the control group (HR = 0.69, 95% CI: 0.57-0.84, P = 0.0003). Regarding the incidence of total adverse events, no significant difference was seen between the two groups (OR = 2.16, 95% CI: 0.98-4.79, P = 0.06), but for specific adverse events, such as leukopenia and neutropenia, the T-DM1 group demonstrated a significant reduction relative to the other treatment regimens. The results underscore the potential of T-DM1 in enhancing survival among patients with advanced HER2-positive breast cancer, yet they also highlight variability in effectiveness concerning pCR rate and ORR. The findings on adverse effects underscore the necessity of a balanced consideration of T-DM1's risks and benefits. Future research should focus on a more detailed examination of responses in varied patient populations, long-term outcomes, and a thorough economic evaluation of T-DM1, along with an exploration into treatment resistance. This will provide a more nuanced understanding of T-DM1's role in the treatment landscape of HER2-positive breast cancer.

Generation of a Novel SORT1×HER2 Bispecific Antibody-Drug Conjugate Targeting HER2-Low-Expression Tumor

Human epidermal growth factor receptor 2 (HER2) is considered an ideal antibody-drug conjugate (ADC) target because the gene is overexpressed in many tumors compared to normal tissues. Multiple anti-HER2 ADCs conjugated with different toxic payloads bring benefits to patients with high HER2 expression. However, HER2-targeted ADC technology needs further optimization to improve its effect for the treatment of patients with low HER2 expression. We hypothesized that bispecific antibody-drug conjugate (bsADC) targeting HER2 and Sortilin-1 (SORT1) would overcome this limitation. SORT1 is a suitable target for pairing with HER2 to generate a bispecific antibody (BsAb) since the gene is co-expressed with HER2 in tumors and possesses rapid internalization. We developed a BsAb (bsSORT1×HER2) that exhibited strong binding and internalization activity on HER2-low-expression tumor cells and facilitated higher HER2 degradation. The bsSORT1×HER2 was further conjugated with DXd to generate a bsADC (bsSORT1×HER2-DXd) that showed strong cytotoxicity on HER2-low-expression tumor cells and antitumor efficacy in an MDA-MB-231 xenograft mice model. These results demonstrated that employment of a SORT1×HER2-targeted bsADC may be promising to improve the antitumor efficacy of HER2-targeted ADC for the treatment of tumors with low HER2 expression.

Amelioration of the therapeutic potential of gefitinib against breast cancer using nanostructured lipid carriers

Aim: This study aimed to improve the delivery and therapeutic potential of gefitinib (GTB) against breast cancer by preparing GTB-loaded, nanostructured lipid carriers (GTB-NLCs). Materials & methods: Box-Behnken design was used for optimization and GTB was loaded into NLCs using ultrasonication. The GTB-NLCs were characterized using in vitro, ex vivo and in vivo studies. The anticancer efficacy of GTB-NLCs was evaluated using 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide cytotoxicity and flow cytometry on MCF-7 breast cancer cell lines. Results: Optimized GTB-NLCs were successfully characterized and demonstrated improved internalization and enhanced cytotoxicity compared with plain GTB. Gut permeation studies showed enhanced intestinal permeability, and pharmacokinetic analysis revealed 2.6-fold improvement in GTB oral bioavailability. Conclusion: GTB-NLCs effectively enhanced the therapeutic potential of GTB against breast cancer.

Upregulated Expression of ERBB2/HER2 in Multiple Myeloma as a Predictor of Poor Survival Outcomes

The main goal of the present study was to examine if the RNA-sequencing (RNAseq)-based ERBB2/HER2 expression level in malignant plasma cells from multiple myeloma (MM) patients has clinical significance for treatment outcomes and survival. We examined the relationship between the RNAseq-based ERBB2 messenger ribonucleic acid (mRNA) levels in malignant plasma cells and survival outcomes in 787 MM patients treated on contemporary standard regimens. ERBB2 was expressed at significantly higher levels than ERBB1 as well as ERBB3 across all three stages of the disease. Upregulated expression of ERBB2 mRNA in MM cells was correlated with amplified expression of mRNAs for transcription factors (TF) that recognize the ERBB2 gene promoter sites. Patients with higher levels of ERBB2 mRNA in their malignant plasma cells experienced significantly increased cancer mortality, shorter progression-free survival, and worse overall survival than other patients. The adverse impact of high ERBB2 expression on patient survival outcomes remained significant in multivariate Cox proportional hazards models that accounted for the effects of other prognostic factors. To the best of our knowledge, this is the first demonstration of an adverse prognostic impact of high-level ERBB2 expression in MM patients. Our results encourage further evaluation of the prognostic significance of high-level ERBB2 mRNA expression and the clinical potential of ERBB2-targeting therapeutics as personalized medicines to overcome cancer drug resistance in high-risk as well as relapsed/refractory MM.

Emerging Intrinsic Therapeutic Targets for Metastatic Breast Cancer

Breast cancer is now the most common cancer worldwide, and it is also the main cause of cancer-related death in women. Survival rates for female breast cancer have significantly improved due to early diagnosis and better treatment. Nevertheless, for patients with advanced or metastatic breast cancer, the survival rate is still low, reflecting a need for the development of new therapies. Mechanistic insights into metastatic breast cancer have provided excellent opportunities for developing novel therapeutic strategies. Although high-throughput approaches have identified several therapeutic targets in metastatic disease, some subtypes such as triple-negative breast cancer do not yet have an apparent tumor-specific receptor or pathway to target. Therefore, exploring new druggable targets in metastatic disease is a high clinical priority. In this review, we summarize the emerging intrinsic therapeutic targets for metastatic breast cancer, including cyclin D-dependent kinases CDK4 and CDK6, the PI3K/AKT/mTOR pathway, the insulin/IGF1R pathway, the EGFR/HER family, the JAK/STAT pathway, poly(ADP-ribose) polymerases (PARP), TROP-2, Src kinases, histone modification enzymes, activated growth factor receptors, androgen receptors, breast cancer stem cells, matrix metalloproteinases, and immune checkpoint proteins. We also review the latest development in breast cancer immunotherapy. Drugs that target these molecules/pathways are either already FDA-approved or currently being tested in clinical trials.

Trastuzumab Deruxtecan: A Review in Unresectable or Metastatic HER2-Positive Breast Cancer

Trastuzumab deruxtecan (Enhertu^®) is a human epidermal growth factor receptor 2 (HER2)-targeted antibody-drug conjugate approved in several countries, including the USA and those of the EU, for adults with unresectable or metastatic HER2-positive breast cancer who have previously received at least one prior anti-HER2-based regimen. In a pivotal phase 3 trial in this setting, intravenous trastuzumab deruxtecan demonstrated prolonged progression-free survival compared with trastuzumab emtansine (previously the recommended second-line therapy in this indication). Trastuzumab deruxtecan had a generally manageable safety and tolerability profile. Common treatment-related adverse events included haematological and gastrointestinal disorders. Interstitial lung disease (ILD)/pneumonitis is associated with a regulatory warning and requires careful monitoring. In conclusion, trastuzumab deruxtecan is a valuable new treatment option for HER2-positive breast cancer, having been shown to be effective with a generally manageable safety and tolerability profile in adults with unresectable or metastatic disease who have received one or more prior anti-HER2-based regimens.

Effective Combination Therapies for the Treatment of HER2 Cancer

Breast cancer (BC) is the primary cause of cancer-related death among women worldwide. The human epidermal growth factor receptor type 2 (HER2)-positive BC accounts for ∼15% of all BCs and a relatively poor prognosis. The disclosure in this patent highlight relates to a combination therapy comprising inavolisib (GDC-0077) and a HER2-targeted therapy such as trastuzumab, pertuzumab, or their combination for the treatment of HER2-overexpressing breast cancer.

Impact of tissue-agnostic approvals for patients with gastrointestinal malignancies

Gastrointestinal (GI) malignancies encompass a broad range of tumors with limited treatment options, particularly for advanced disease. With the development and implementation of next-generation sequencing (NGS) in routine practice, molecular-targeting therapies have been increasingly incorporated into the treatment paradigm for various cancers. Several drugs have achieved tissue-agnostic regulatory approvals, which offer promising biomarker-driven therapy options for patients with advanced GI malignancies. In this review, we focus on the clinical evidence for recent drug approvals for neurotrophic tyrosine receptor kinase (NTRK) fusion, microsatellite instability-high (MSI-H) phenotype, tumor mutation burden-high (TMB-H), BRAF V600E, and rearranged during transfection (RET), in the context of GI malignancies. We also highlight the future landscape of tissue-agnostic targets, such as human epidermal growth factor receptor 2 (HER2)/neu, fibroblast growth factor receptor (FGFR), and neuregulin (NRG)-1.

The Value of Tucatinib in Metastatic HER2-Positive Breast Cancer Patients: An Italian Cost-Effectiveness Analysis

BACKGROUND

This study was aimed at estimating the appropriate price of tucatinib plus trastuzumab and capecitabine (TXC), as third-line treatment, in HER2⁺ breast cancer (BC) patients from the Italian National Health System (NHS) perspective.

METHODS

A partitioned survival model with three mutually exclusive health states (i.e., progression-free survival (PFS), progressive disease (PD), and death) was used to estimate the price of tucatinib vs trastuzumab emtansine (TDM-1), considering a willingness to pay (WTP) of 60,000 EUR. Data from the HER2CLIMB trial, the Italian population, and the literature were used as input. The model also estimated the total costs and the life-years (LY) of TXC and TDM1. Deterministic and probabilistic (PSA) sensitivity analyses were conducted to evaluate the robustness of the model.

RESULTS

In the base case scenario, the appropriate price of tucatinib was 4828.44 EUR per cycle. The TXC resulted in +0.28 LYs and +16,628 EUR compared with TDM-1. Results were mainly sensitive to therapy intensity variation. In PSA analysis, TXC resulted cost-effective in 53% of the simulations. Assuming a WTP ranging 20,000-80,000 EUR, the tucatinib price ranged from 4090.60 to 5197.41 EUR.

CONCLUSIONS

This study estimated the appropriate price for tucatinib according to different WTP in order to help healthcare decision makers to better understand the treatment value.