Pyrotinib Combined With Vinorelbine in HER2-Positive Metastatic Breast Cancer: A Multicenter Retrospective Study

Pyrotinib Combined with Vinorelbine in Patients with Previously Treated HER2-Positive Metastatic Breast Cancer: A Multicenter, Single-Arm, Prospective Study

PURPOSE

This study aims to evaluate the efficacy and safety of a new combination treatment of vinorelbine and pyrotinib in human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) and provide higher level evidence for clinical practice.

MATERIALS AND METHODS

This was a prospective, single-arm, phase 2 trial conducted at three institutions in China. Patients with HER2-positive MBC, who had previously been treated with trastuzumab plus a taxane or trastuzumab plus pertuzumab combined with a chemotherapeutic agent, were enrolled between March 2020 and December 2021. All patients received pyrotinib 400 mg orally once daily plus vinorelbine 25 mg/m2 intravenously or 60-80 mg/m2 orally on day 1 and day 8 of 21-day cycle. The primary endpoint was progression-free survival (PFS), and the secondary endpoints included the objective response rate (ORR), disease control rate (DCR), overall survival, and safety.

RESULTS

A total of 39 patients were enrolled. All patients had been pretreated with trastuzumab and 23.1% (n=9) of them had accepted trastuzumab plus pertuzumab. The median follow-up time was 16.3 months (95% confidence interval [CI], 5.3 to 27.2), and the median PFS was 6.4 months (95% CI, 4.0 to 8.8). The ORR was 43.6% (95% CI, 27.8% to 60.4%) and the DCR was 84.6% (95% CI, 69.5% to 94.1%). The median PFS of patients with versus without prior pertuzumab treatment was 4.6 and 8.3 months (p=0.017). The most common grade 3/4 adverse events were diarrhea (28.2%), neutrophil count decreased (15.4%), white blood cell count decreased (7.7%), vomiting (5.1%), and anemia (2.6%).

CONCLUSION

Pyrotinib plus vinorelbine showed promising efficacy and tolerable toxicity as second-line treatment in patients with HER2-positive MBC.

Ferroptosis biomarkers predict tumor mutation burden's impact on prognosis in HER2-positive breast cancer

BACKGROUND

Ferroptosis has recently been associated with multiple degenerative diseases. Ferroptosis induction in cancer cells is a feasible method for treating neoplastic diseases. However, the association of iron proliferation-related genes with prognosis in HER2+ breast cancer (BC) patients is unclear.

AIM

To identify and evaluate fresh ferroptosis-related biomarkers for HER2+ BC.

METHODS

First, we obtained the mRNA expression profiles and clinical information of HER2+ BC patients from the TCGA and METABRIC public databases. A four-gene prediction model comprising PROM2, SLC7A11, FANCD2, and FH was subsequently developed in the TCGA cohort and confirmed in the METABRIC cohort. Patients were stratified into high-risk and low-risk groups based on their median risk score, an independent predictor of overall survival (OS). Based on these findings, immune infiltration, mutations, and medication sensitivity were analyzed in various risk groupings. Additionally, we assessed patient prognosis by combining the tumor mutation burden (TMB) with risk score. Finally, we evaluated the expression of critical genes by analyzing single-cell RNA sequencing (scRNA-seq) data from malignant vs normal epithelial cells.

RESULTS

We found that the higher the risk score was, the worse the prognosis was (P < 0.05). We also found that the immune cell infiltration, mutation, and drug sensitivity were different between the different risk groups. The high-risk subgroup was associated with lower immune scores and high TMB. Moreover, we found that the combination of the TMB and risk score could stratify patients into three groups with distinct prognoses. HRisk-HTMB patients had the worst prognosis, whereas LRisk-LTMB patients had the best prognosis (P < 0.0001). Analysis of the scRNA-seq data showed that PROM2, SLC7A11, and FANCD2 were significantly differentially expressed, whereas FH was not, suggesting that these genes are expressed mainly in cancer epithelial cells (P < 0.01).

CONCLUSION

Our model helps guide the prognosis of HER2+ breast cancer patients, and its combination with the TMB can aid in more accurate assessment of patient prognosis and provide new ideas for further diagnosis and treatment.

The Efficacy and Safety of Inetetamab and Pyrotinib in Combination with Vinorelbine for Second-line Therapy and Beyond in HER2-positive Metastatic Breast Cancer: A Single-institution Clinical Experience

BACKGROUND AND OBJECTIVES

This study aimed to observe the efficacy and safety of inetetamab and pyrotinib in combination with vinorelbine in second-line therapy and beyond in HER2-positive metastatic breast cancer (MBC).

METHODS

Patients with HER2-positive MBC admitted to our hospital from January 2016 to December 2021 were selected. For patients who could not receive antibody‒drug conjugates (ADCs) during second-line (2nd-line) or third-line and beyond (≥ 3rd-line) anti-HER2 therapy, inetetamab + pyrotinib + vinorelbine was used for treatment until unacceptable adverse events occurred or the disease progressed, as evaluated by the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 every 2 cycles. The progression-free survival (PFS), objective response rate (ORR), clinical benefit rate (CBR), and adverse reactions were recorded. Multivariate Cox regression analysis was performed to explore the prognostic factors influencing the curative effect.

RESULTS

Overall, 52 patients were included; 13 patients received 2nd-line treatment, and 39 patients received ≥ 3rd-line treatment. The median PFS (mPFS) for all patients treated with inetetamab + pyrotinib + vinorelbine was 7 months. The mPFS of the 2nd-line subgroup was significantly better than that of the ≥ 3rd-line subgroup (17 vs. 5 months, P = 0.001). The mPFS of the subgroups that received trastuzumab (H) or trastuzumab and pertuzumab (HP) only was significantly better than that of the H or HP and tyrosine kinase inhibitor (TKI) subgroups (8 vs. 5 months, P = 0.030). The mPFS of the HER2 resistance subgroup was better than that of the HER2 refractoriness subgroup (14 vs. 7 months, P = 0.025). Cox regression analysis showed that the treatment line (2nd-line more so than ≥ 3rd-line) was an independent prognostic factor for PFS. In addition, the ORR and CBR of 2nd-line patients were significantly higher than those of ≥ 3rd-line patients (69.2% vs. 30.8% and 92.3% vs. 64.1%, respectively). The most common hematological toxicities were leukopenia and neutropenia, and the most common nonhematological toxicity was diarrhea.

CONCLUSION

Inetetamab and pyrotinib in combination with vinorelbine have good efficacy in ≥ 2nd-line treatment of HER2-positive MBC with controllable toxicity, and the combination is a new treatment option, especially for patients who cannot use ADCs in 2nd-line treatment.

Real-world data of triplet combination of pyrotinib, trastuzumab, and chemotherapy in HER2-positive metastatic breast cancer: a multicenter, retrospective study

Background

Pyrotinib, an irreversible pan-human epidermal growth (HER) inhibitor, has proven its antitumor efficacy as a second-line treatment for HER2-positive metastatic breast cancer (HER2+ MBC) when combined with capecitabine. However, real-world data concerning the pyrotinib, trastuzumab, and chemotherapy (PyroHC) combination remains scarce.

Objectives

Our study is to report the treatment patterns, efficacy, and safety of the PyroHC combination in a real-world setting.

Design

This study enrolled patients with HER2+ MBC from five institutions in China, treated with PyroHC between June 2017 and January 2023 (ClinicalTrials.gov, identifier: NCT05839288).

Methods

We evaluated progression-free survival (PFS), objective response rate (ORR), toxicity profile, and utilized treatment regimens.

Results

Of the 135 patients in our cohort, 91.9% had prior trastuzumab exposure and 52.2% underwent at least two systematic therapy lines before receiving PyroHC. The most prevalent chemotherapies paired with PyroH were capecitabine (36.3%). Patients receiving PyroHC achieved a median PFS of 8.67 months [95% confidence interval (CI): 6.84-10.51] and an ORR of 51.3% (95% CI: 42.1-61.5%). The first-line treatment with PyroHC led to a median PFS of 14.46 months (95% CI: 6.35-22.56). Patients with brain metastases showed a median PFS of 9.03 months (95% CI: 6.56-11.50), achieving an ORR of 52.17% (95% CI: 51.74-83.39). Longer previous trastuzumab (⩾6.37 months) or lapatinib (⩾10.05 months) therapies could indicate improved PFS, while prior pyrotinib exposure negatively influenced PFS. Notably, the most common grade 3/4 adverse events were diarrhea (37.8%), which were generally manageable.

Conclusion

PyroHC shows promising efficacy and a satisfactory safety profile for treating HER2+ MBC, both as a first-line option and for heavily treated patients, including those with brain metastasis. Our findings suggest the duration and history of anti-HER2 therapy as potential predictors for PyroHC efficacy in advanced settings.

Comparing pyrotinib with trastuzumab and pertuzumab with trastuzumab for HER2-positive metastatic breast cancer: a retrospective, multicenter analysis

Objective

Pyrotinib and pertuzumab are effective treatment options for HER2-positive metastatic breast cancer (HER2+ MBC). Our study was to directly compare the efficacy and safety of pyrotinib plus trastuzumab (PyroH) and pertuzumab plus trastuzumab (HP) in patients with HER2+ MBC.

Methods

We conducted a retrospective examination of HER2+ MBC patients who received PyroH plus chemotherapy or HP plus chemotherapy between 2017 and 2022 at five institutions in China. Our primary endpoint was progression-free survival (PFS).

Results

This study involved 333 patients, among which 161 received PyroH and 172 received HP. The utilization of PyroH as a first-line therapy for MBC was more prevalent among older patients, those with a shorter duration of disease-free interval, or those who had previously been treated with trastuzumab. Although in the first-line advanced treatment HP cohort showed numerically longer PFS (median PFS: 14.46 vs. 22.90 months, p=0.057), in the second-line or later treatments, there was no significant difference in PFS between the PyroH and HP groups (median PFS: 8.67 vs. 7.92 months, p=0.286). Despite HP showing a longer PFS in the overall cohort (median PFS: 9.30 vs. 13.01 months, p=0.005), it did not serve as an independent predictor of PFS in the multivariate analysis (HR 1.134, 95% CI 0.710-1.811, p=0.598). Without taxane, PyroH demonstrated a longer PFS than HP (median PFS: 10.12 vs. 8.15 months, p=0.017). PyroH group displayed a numerically longer median PFS in patients with brain metastases compared to the HP group, though not statistically significant (median PFS: 9.03 vs. 8.15 months, p=0.976). PyroH had higher incidence of grade 3/4 diarrhea (34.3% vs. 3.0%) but similar overall adverse events.

Conclusion

In conclusion, PyroH is comparable in second-line or later treatment and during brain metastasis, even having superior efficacy without taxane in real-world setting. Toxicities were tolerable in both groups. (ClinicalTrials.gov: NCT05572645).

Efficacy and safety of inetetamab-containing regimens in patients with HER2-positive metastatic breast cancer: a real-world retrospective study in China

Background

Inetetamab (cipterbin) is an innovative anti-HER2 humanized monoclonal antibody. The efficacy and safety of a combination of inetetamab and vinorelbine in the first-line treatment of human epidermal receptor positive (HER2+) metastatic breast cancer (MBC) have been confirmed. We aimed to investigate real-world data of inetetamab in complex clinical practice.

Methods

We retrospectively reviewed the medical records of patients who received inetetamab as a salvage treatment at any line setting from July 2020 to June 2022. The main endpoint was progression-free survival (PFS).

Results

A total of 64 patients were included in this analysis. The median progression-free survival (mPFS) was 5.6 (4.6-6.6) months. Of the patients, 62.5% received two or more lines of therapy before treatment with inetetamab. The most common chemotherapy and anti-HER2 regimens combined with inetetamab were vinorelbine (60.9%) and pyrotinib (62.5%), respectively. Patients treated with inetetamab plus pyrotinib plus vinorelbine benefited the most (p=0.048), with the mPFS of 9.3 (3.1-15.5) months and an objective response rate of 35.5%. For patients with pyrotinib pretreatment, inetetamab plus vinorelbine plus pyrotinib agents resulted in mPFS of 10.3 (5.2-15.4) months. Regimens (inetetamab plus vinorelbine plus pyrotinib vs. other therapeutic agents) and visceral metastases (yes vs. no) were independent predictors of PFS. Patients with visceral metastases treated with inetetamab plus vinorelbine plus pyrotinib had a mPFS of 6.1(5.1-7.1) months. The toxicity of inetetamab was tolerable, with the most common grade 3/4 adverse event being leukopenia (4.7%).

Conclusions

HER2+ MBC patients pretreated with multiple-line therapies still respond to inetetamab-based treatment. Inetetamab combined with vinorelbine and pyrotinib may be the most effective treatment regimen, with a controllable and tolerable safety profile.

Neoadjuvant pyrotinib plus trastuzumab and vinorelbine for HER2-positive locally advanced breast cancer patient who was initially resistant to HP therapy: a case report and literature review

Background

Trastuzumab (H) and pertuzumab (P) plus chemotherapy is the standard guideline-recommended neoadjuvant therapy recommended for patients with human epidermal growth factor receptor 2 (HER2)-positive locally advanced breast cancer (BC), which has dramatically improved patient prognosis. However, over 10% of patients develop primary drug resistance to HP and did not respond to treatment. There is no standard second-line neoadjuvant therapy approach for these individuals at the present. Pyrotinib and vinorelbine have shown promising efficacy in HER2-positive metastatic breast cancer, but their usage in neoadjuvant therapy has not been reported so far.

Case Description

Here, we present a case of a 58-year-old female patient with locally advanced HER2-positive BC who was initially resistant to HP neoadjuvant therapy. Following the failure of the treatment, this patient was given pyrotinib plus trastuzumab and vinorelbine as second-line neoadjuvant therapy. The patient tolerated this treatment well, with mild symptoms of diarrhea. After 6 cycles of neoadjuvant therapy, the efficacy was assessed to be partial remission (PR), and a modified radical mastectomy was finally conducted. This patient remained disease-free for 23 months after surgery.

Conclusions

This is the first report to present a case of neoadjuvant pyrotinib plus trastuzumab and vinorelbine in a patient with HER2-positive locally advanced BC, suggesting that the combination could be a new option for patients who have developed resistance to HP neoadjuvant treatment.

Pyrotinib for HER2-positive metastatic breast cancer: a systematic review and meta-analysis

Background

Human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer patients continue to progress despite multiple anti-HER2-targeted treatments. A number of studies have found that Pyrotinib, a small-molecule pan-ErbB receptor tyrosine kinase inhibitor (TKI), is effective in treating patients with HER2-positive metastatic breast cancer. This systematic review and meta-analysis aimed to evaluate the efficacy and safety of Pyrotinib in the treatment of HER2-positive metastatic breast cancer.

Methods

PubMed, Embase, Web of Science, and Cochrane Library databases were searched until February 2022. Research on HER2-positive metastatic breast cancer being treated with Pyrotinib in any line of therapy was included, both prospective and retrospective. Statistical pooling and meta-analysis of data from the included studies were performed to explore the efficacy and safety of Pyrotinib in HER2-positive metastatic breast cancer.

Results

In this meta-analysis, 23 studies were included. The overall objective response rate was 0.49 (95% CI: 0.40, 0.58) for Pyrotinib in HER2-positive metastatic breast cancer and 0.52 (95% CI: 0.32, 0.71) in those with brain metastases. The objective response rate of Pyrotinib was superior to that of other second-line therapeutics in comparison (RR =1.38, 95% CI: 1.25, 1.52), but was relatively inferior to trastuzumab emtansine (T-DM1) (RR =0.82, 95% CI: 0.36, 1.85). The combined median progression-free survivals (PFSs) for Pyrotinib in metastatic breast cancer and those with brain metastases were 8.2 (95% CI: 6.8, 9.5) months and 8.9 (95% CI: 6.2, 11.7) months, respectively. The most common adverse reaction was diarrhea with an all-grade incidence of 0.84 (95% CI: 0.74, 0.92), followed by nausea and vomiting of 0.52 (95% CI: 0.36, 0.68).

Conclusions

In any line of treatment for HER2-positive metastatic breast cancer, the Pyrotinib-containing regimens demonstrated considerable tumor response, disease control, and survival with manageable adverse effects.

The role of irreversible pan-HER tyrosine kinase inhibitors in the treatment of HER2-Positive metastatic breast cancer

Human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) is the leading cause of cancer death in women. For patients with HER2-positive MBC, after the failure of multiple lines of treatment, there is no optimal line of therapy. A series of clinical trials confirmed that treatment with irreversible pan-HER tyrosine kinase inhibitors (TKIs) in combination with chemotherapy significantly improves patients' survival outcomes. This review focuses on the pathogenesis of HER2-positive breast cancer, current standard treatments, mechanisms of approved irreversible TKIs, and key clinical trials. The available findings suggest that irreversible pan-HER TKIs, such as pyrotinib and neratinib, in combination with chemotherapy, represent a beneficial salvage therapy for patients with HER2-positive MBC with manageable toxicity. However, further studies are needed to assess the efficacy and safety of this combination therapy.

Pyrotinib-based treatments in HER2-positive breast cancer patients with brain metastases

OBJECTIVES

Extensive application of anti-HER2 targeted therapy improves significantly the HER2-positive advanced breast cancer (BC) prognosis, however, it is still difficult to treat brain metastasis. In current study, we explored effective approaches via combining pyrotinib to treat brain metastasis in patients with HER2-positive advanced BC based upon clinical data.

MATERIALS AND METHODS

Current study included 61 HER2-positive BC patients with brain metastases (BM) who were treated by pyrotinib-based regimens. The systemic regimens included pyrotinib combined with capecitabine, pyrotinib combined with nab-paclitaxel, and pyrotinib combined with vinorelbine. Patients' progression-free survival (PFS), overall survival (OS), clinical benefit rate (CBR) and objective response rate (ORR), as well as drug-related adverse events (AEs) in regard of each combination regimen were analyzed.

RESULTS

Pyrotinib-based systemic therapy resulted in 8.6 months median PFS (mPFS) and 18.0 months median OS (mOS) among the BM patients. Regarding different regimens, the combination of pyrotinib with nab-paclitaxel was superior to the combination with capecitabine and vinorelbine with respect to PFS and OS. The central nervous system (CNS) ORR did not showcase significant difference among 3 regimens, however, nab-paclitaxel combined regimen obtained the best peripheral ORR (84.6%) (p ≤ .05).

CONCLUSIONS

Pyrotinib-based combination therapy is safe for HER2-positive brain metastasis treatment. Compared with vinorelbine or capecitabine, pyrotinib combined with nab-paclitaxel is more effective with less toxicity, which is the preferable regimen for HER2-positive brain metastasis.KEY MESSAGESPresent investigation investigated effective methods through combining pyrotinib to treat brain metastasis with HER2-positive advanced brain cancer. The outcomes verified that pyrotinib-based combination therapy was safe and efficient to treat HER2-positive brain metastasis. Therefore, it is effective to treat brain metastasis applying anti-HER2 targeted therapies although pyrotinib showcases efficiency regarding its treatments for the metastasis.

Systemic Therapy for Patients with HER2-Positive Breast Cancer and Brain Metastases: A Systematic Review and Meta-Analysis

AIM

Patients with HER2-positive (HER2+) metastatic breast cancer (mBC) develop brain metastases (BM) in up to 30% of cases. Treatment of patients with BM can consist of local treatment (surgery and/or radiotherapy) and/or systemic treatment. We undertook a systematic review and meta-analysis to determine the effect of different systemic therapies in patients with HER2+ mBC and BM.

METHODS

A systematic search was performed in the databases PubMed, Embase.com, Clarivate Analytics/Web of Science Core Collection and the Wiley/Cochrane Library. Eligible articles included prospective or retrospective studies reporting on the effect of systemic therapy on objective response rate (ORR) and/or median progression free survival (mPFS) in patients with HER2+ mBC and BM. The timeframe within the databases was from inception to 19 January 2022. Fixed-effects meta-analyses were used. Quality appraisal was performed using the ROBINS-I tool.

RESULTS

Fifty-one studies were included, involving 3118 patients. Most studies, which contained the largest patient numbers, but also often carried a moderate-serious risk of bias, investigated lapatinib and capecitabine (LC), trastuzumab-emtansine (T-DM1) or pyrotinib. The best quality data and/or highest ORR were described with tucatinib (combined with trastuzumab and capecitabine, TTC) and trastuzumab-deruxtecan (T-DXd). TTC demonstrated an ORR of 47.3% in patients with asymptomatic and/or active BM. T-DXd achieved a pooled ORR of 64% (95% CI 43-85%, I² 0%) in a heavily pretreated population with asymptomatic BM (3 studies, n = 96).

CONCLUSIONS

Though our meta-analysis should be interpreted with caution due to the heterogeneity of included studies and a related serious risk of bias, this review provides a comprehensive overview of all currently available systemic treatment options. T-Dxd and TTC that appear to constitute the most effective systemic therapy in patients with HER2+ mBC and BM, while pyrotinib might be an option in Asian patients.

Differential effects of ketoconazole, fluconazole, and itraconazole on the pharmacokinetics of pyrotinib in vitro and in vivo

It has been reported that drug-drug interactions (DDIs) can affect the pharmacokinetics and pharmacodynamics of various oral drugs. To better understand the effects of azole antifungal drugs (ketoconazole, fluconazole, and itraconazole) on pyrotinib’s pharmacokinetics, DDIs between pyrotinib and three azoles were studied with Sprague-Dawley (SD) rat liver microsomes in vitro. Additionally, in vivo pyrotinib metabolic experiment was also performed. Twenty-four male SD rats were randomly divided into four groups: the ketoconazole (40 mg/kg), fluconazole (40 mg/kg), itraconazole (40 mg/kg), and the control group. UPLC-MS/MS was used for the determination of Pyrotinib’s plasma concentration in rats. In vitro experiments showed that IC₅₀ values of ketoconazole, fluconazole and itraconazole were 0.06, 11.55, and 0.27 μM, respectively, indicating that these drugs might reduce the clearance rate of pyrotinib at different degrees. In rat studies, coadministration of pyrotinib with ketoconazole or fluconazole could dramatically increase the C_max and AUC_(0-t) values and decrease the clearance rate of pyrotinib, especially for ketoconazole. However, coadministration with itraconazole had no impact on the pharmacokinetic characters of pyrotinib. These data indicated that ketoconazole and fluconazole could significantly decrease the metabolism of pyrotinib both in vitro and in vivo. More attentions should be paid when pyrotinib is combined with azole antifungal drugs in clinic although further investigation is still required in future.

Cost-Effectiveness of Pyrotinib Plus Capecitabine versus Lapatinib Plus Capecitabine for the Treatment of HER2-Positive Metastatic Breast Cancer in China: A Scenario Analysis of Health Insurance Coverage

Background: The overexpression of the human epidermal growth factor receptor-2 (HER2) gene is present in 20~25% of breast cancer (BC) patients, contributing to an inferior prognosis. Recent clinical trials showed that pyrotinib has promising antitumor activities and acceptable tolerability for those patients (ClinicalTrials.gov, NCT03080805 and NCT02422199). Therefore, this study aims to assess the cost-effectiveness of pyrotinib plus capecitabine versus lapatinib plus capecitabine for patients with HER2-positive metastatic BC after prior trastuzumab. Methods: A lifetime-partitioned survival model was established to evaluate health and economic outcomes with different treatment strategies. The primary outcome was the incremental cost-effectiveness ratio (ICER). Data were derived from the published literature, clinical trials, expert opinions, and other local charges. Sensitivity analyses were performed to assess the robustness of the findings. Scenario analyses were developed to make further evaluations. Results: The pyrotinib regimen had significant advantages over the lapatinib regimen after enrolling in the National Reimbursement Drug List (NRDL), with cost savings of USD 15,599.27 and a gain of 0.53 QALYs. Meanwhile, before enrolling in NRDL, the pyrotinib regimen afforded the same QALYs at a higher incremental cost of USD 45,400.64 versus the lapatinib regimen, producing an ICER of USD 85,944.79 per QALY. Scenario analyses yielded similar results. Sensitivity analyses suggested stability in the cost-effectiveness findings. Conclusions: Compared to lapatinib plus capecitabine, the pyrotinib plus capecitabine enrolled in NRDL is a cost-effective alternative second-line treatment for patients with HER2-positive metastatic BC in China.

Temporal Heterogeneity of HER2 Expression and Spatial Heterogeneity of 18F-FDG Uptake Predicts Treatment Outcome of Pyrotinib in Patients with HER2-Positive Metastatic Breast Cancer

Background: This study aimed to evaluate tumor heterogeneity of metastatic breast cancer (MBC) and investigate its impact on the efficacy of pyrotinib in patients with HER2-positive MBC. Methods: MBC patients who underwent 18F-FDG PET/CT before pyrotinib treatment were included. Temporal and spatial tumor heterogeneity was evaluated by the discordance between primary and metastatic immunohistochemistry (IHC) results and baseline 18F-FDG uptake heterogeneity (intertumoral and intratumoral heterogeneity indexes: HI-inter and HI-intra), respectively. Progression-free survival (PFS) was estimated by the Kaplan−Meier method and compared by a log-rank test. Results: A total of 572 patients were screened and 51 patients were included. In 36 patients with matched IHC results, 25% of them had HER2 status conversion. Patients with homogenous HER2 positivity had the longest PFS, followed by patients with gained HER2 positivity, while patients with HER2 negative conversion could not benefit from pyrotinib (16.8 vs. 13.7 vs. 3.6 months, p < 0.0001). In terms of spatial heterogeneity, patients with high HI-intra and HI-inter had significantly worse PFS compared to those with low heterogeneity (10.6 vs. 25.3 months, p = 0.023; 11.2 vs. 25.3 months, p = 0.040). Conclusions: Temporal heterogeneity of HER2 status and spatial heterogeneity of 18F-FDG uptake could predict the treatment outcome of pyrotinib in patients with HER2-positive MBC, which provide practically applicable methods to assess tumor heterogeneity and guidance for treatment decisions.

Efficacy and safety of pyrotinib-containing regimen in the patients with HER2-positive metastatic breast cancer: A multicenter real-world study

BACKGROUND

Pyrotinib, a novel irreversible epidermal growth factor receptor 2 (EGFR)/HER2 dual tyrosine kinase inhibitor, has shown promising antitumor efficacy with tolerable toxicity in HER2-positive metastatic breast cancer (MBC) in several clinical trials. However, the clinical trials do not usually well reflect the patients in real clinical settings. Despite several small-sample studies in real world, the data on pyrotinib as first-line and third-or-later-line treatment and the efficacy comparison of pyrotinib combined with different regimens are still lacking. Therefore, this study aimed to investigate the efficacy and safety of pyrotinib for the HER2-positive MBC in real world to replenish more comprehensive data.

METHODS

A total of 172 HER2-positive MBC patients treated with pyrotinib-based therapy were recruited from multiple centers in nonclinical trial settings from September 2017 to June 2020.

RESULTS

The median progression-free survival (mPFS) of 172 patients was 8.83 months. The patients, receiving first-line pyrotinib treatment, had the longest mPFS (20.93 months) compared with those receiving second-line (8.67 months, p = 0.0339) and third-or-later-line (7.13 months, p = 0.0075) treatments, respectively. Prior treatment with lapatinib (p = 0.012) and site of metastasis (visceral vs. nonvisceral) (p = 0.033) were the independent prognostic factors for PFS. The prior treatment with lapatinib compared with lapatinib-native treatment (5.96 vs. 10.97 months, p = 0.0036) and those with visceral metastasis compared with nonvisceral metastasis (8.40 vs. 23.70 months, p = 0.0138) had worse mPFS. Among 146 patients evaluated for efficacy, 2.1%, 58.9%, and 32.9% showed complete response, partial response, and stable disease, respectively. Adverse events occurred in 92.4% of the patients with 33.3% Grade 3 and higher adverse events and diarrhea (57.0%), anemia (44.8%), and leukopenia (40.7%) as the most frequent ones.

CONCLUSIONS

Pyrotinib-containing regimen could effectively treat HER2-positive MBC with acceptable toxicity, including the patients who progressed after lapatinib treatment and with brain metastasis.

Treatment with pyrotinib-based therapy in lapatinib-resistant HER2-positive metastatic breast cancer: a multicenter real-world study

Background:

Tyrosine kinase inhibitors (TKIs) are effective for treating human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. However, therapies subsequent to TKI progression remain controversial, and effective treatments for TKI resistance are urgently needed. We evaluate the practice of exchange of TKIs, which involves treatment with a different TKI following prior TKI failure. Specifically, this study investigated the efficacy of pyrotinib-based therapy in lapatinib-resistant HER2-positive metastatic breast cancer (NCT04899128).

Methods:

This real-world study included 76 patients diagnosed with HER2-positive metastatic breast cancer who received pyrotinib-based therapy after lapatinib progression at four Chinese institutions between August 2018 and March 2020. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), clinical benefit rate (CBR), and toxicity profiles were reported.

Results:

All patients received pyrotinib-based therapy in two or later line therapy. The median PFS was 8.0 months (95% CI 5.1–10.9). OS has not reached. The ORR and CBR were 17.1% and 60.5%, respectively. The median PFS was 7.1 months (95% CI 5.633–8.567) and intracranial ORR was 42.9% in patients who had brain metastasis (n = 14). Patients who benefited from lapatinib ⩾ 6.0 months prior exhibited a longer PFS (10.6 versus 6.0 months, p = 0.034, stratified hazard ratio (HR) 0.534, 95% CI 0.293–0.975). The most common adverse effects were diarrhea (n = 34, 44.7%) and hand-foot syndrome (n = 10, 13.2%).

Conclusion:

Pyrotinib-based therapy has the potential to improve survival in patients with lapatinib-resistant HER2-positive metastatic breast cancer, including those with brain metastases. Pyrotinib could provide a clinically significant increase in PFS for patients who benefited from prior lapatinib.

Real-World Analysis of the Efficacy and Safety of a Novel Irreversible HER2 Tyrosine Kinase Inhibitor Pyrotinib in Patients with HER2-Positive Metastatic Breast Cancer

Background

As a novel irreversible pan-ErbB inhibitor recently approved in China, pyrotinib has exhibited promising anticancer efficacy and acceptable safety profile in HER2-positive metastatic breast cancer (mBC). The aim of this retrospective study was to estimate the efficacy and safety of pyrotinib treatment in Chinese mBC patients.

Methods

We retrospectively reviewed the real-world clinicopathological and treatment data of HER2-positive mBC patients receiving pyrotinib-based treatment from August 2018 to July 2019 in Qilu Hospital of Shandong University and other medical centers of Shandong Province in China.

Results

A total of 64 patients treated with pyrotinib were included for analysis, and the median follow-up duration was 260 days (interquartile range, 199.0 to 339.0 days). Fifty-nine (92.2%) patients had been previously treated with trastuzumab and/or T-DM1, while 11 (17.2%) patients had been exposed to lapatinib. The objective response rate (ORR) of all patients was 73.4%, and the disease control rate (DCR) was 98.4%, with a clinical benefit rate (CBR) of 87.5%. Patients with exposure to lapatinib responded well to pyrotinib-based treatment, although the ORR was significantly lower compared with that of patients without exposure to lapatinib (44.1% vs 77.5%, p=0.037). Previous lapatinib exposure was negatively associated with the objective response of pyrotinib treatment (odds ratio [OR]=0.248, 95% confidence interval [CI] 0.063–0.970, p=0.045). The median progression-free survival (mPFS) for patients with previous lapatinib exposure and patients with visceral metastasis was 299 days (95% CI 240.1–357.9 days) and 359 days (95% CI 258.3–459.7 days), respectively. But the mPFS of the whole cohort has not been reached until the cut-off date. Cox multivariate analysis revealed that only visceral metastasis was an independent predictor of significantly shorter PFS (p=0.041) but not previous exposure to lapatinib (p=0.092). Diarrhea (28.1%), hand-foot syndrome (17.2%), and neutropenia (9.4%) were the most common grade 3 adverse events associated with pyrotinib treatment.

Conclusion

Pyrotinib is highly beneficial to HER2-positive metastatic breast cancer patients, even in patients with previous lapatinib exposure. Pyrotinib is a feasible replacement of lapatinib in combination with chemotherapeutic drugs or as a monotherapy. Adverse effects are tolerable and easily manageable.

Pyrotinib Plus Vinorelbine Versus Lapatinib Plus Capecitabine in Patients With Previously Treated HER2-Positive Metastatic Breast Cancer: A Multicenter, Retrospective Study

Background

Pyrotinib is a newly-developed irreversible pan-ErbB (erythroblastic leukemia viral oncogene homolog) receptor oral tyrosine kinase inhibitor (TKI) with promising efficacy in the human epidermal growth factor receptor-2 (HER2) positive breast cancer. The phase III PHOEBE study proved that pyrotinib plus capecitabine exceeded lapatinib plus capecitabine (LX) in PFS (p < 0.001). Oral vinorelbine is commonly used in combination with anti-HER2 treatment. However, no evidence was reported in terms of the real-world pattern, safety, and efficacy of pyrotinib plus vinorelbine (NP) compared with LX.

Methods

Medical records were retrospectively evaluated for all HER2-positive metastatic breast cancer (MBC) patients who experienced progression on prior trastuzumab-containing regimens (advanced setting) and taxane (any setting) and received NP or LX therapy from 2015 to 2021 in five institutions.

Results

A total of 224 patients were enrolled and evaluated, of which 132 (58.9%) patients received LX and 92 (41.1%) patients received NP. The median progression-free survival (mPFS) of NP group was significantly longer than that in LX group (8.3 vs 5.0 months, HR = 0.47 95% CI 0.34–0.65, p < 0.001). The advantage of NP over LX was seen both in patients with trastuzumab resistance (p < 0.001) and refractoriness (p = 0.004). The NP group had more diarrhea cases (23.9%) compared to the LX group (8.3%). Discontinuation rates in the two groups were similar.

Conclusions

This trial revealed the clinical practice of NP and LX treatment among HER2+ MBC patients pretreated with trastuzumab in China. More patients received LX than NP in real-world while the efficacy of NP exceeded LX in terms of PFS regardless of resistant status of trastuzumab. Although the NP group had more diarrhea cases, toxicities in both groups were acceptable.