Search

Objective: Pyrotinb has been approved for the treatment of HER2-positive advanced or metastatic breast cancer in China. However, the plasma concentration of pyrotinb in different patients varies greatly, and in the course of treatment, if patients have intolerable adverse reactions, the drug dosage will be reduced or even stopped. This study set out to establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the determination of pyrotinb in human plasma, analyze the population pharmacokinetics (PPK) of pyrotinib and assess the influence of patient variables on PK of pyrotinib in patients with HER2 positive breast cancer. Method: An UPLC-MS/MS method was developed to measure pyrotinib in human plasma. Utilizing a gradient elution procedure and a Kinetex C18 column (2.1 mm × 100 mm, 1.7 μm), sample separation was accomplished in 5.5 min. Pyrotinb extraction via protein precipitation was used as a sample pre-treatment technique. In total, 50 patients provided 158 plasma samples, which were identified and used in the PPK investigation. The non-linear mixed-effects modeling (NONMEM) approach was used to assess the plasma concentrations and covariates information. For the final PPK model evaluation, external evaluation, non-parametric bootstrap, visual predictive check (VPC), and goodness-of-fit (GOF) were used. Results: The UPLC-MS/MS method for determining plasma concentration of pyrotinib in patients had good selectivity and linearity in the range of 1–1,000 ng/mL. Pyrotinib concentration profile in HER2-positive breast cancer patients was well described by a single-compartment PPK model with first-order absorption and elimination. The formulas for the final estimated values of overall parameters of CL/F and Vd/F and Ka are respectively: C L / F L / h = 88.8 × e TP / 67.2 × 0.376 , V / F L = 3940 , K A h − 1 = 0.357 F I X E D. No dosage adjustment was advised, despite the possibility that the total protein levels could have a substantial impact on the apparent distribution volume of pyrotinib with limited magnitude. Conclusion: In this study, an UPLC-MS/MS method was established to determine the concentration of pyrotinib in human plasma. A population pharmacokinetic model of pyrotinib in HER2 positive breast cancer patients suggested that low serum total protein reduced the clearance rate of pyrotinib in patients. Clinical medical staff should pay attention to the liver function of patients with abnormal serum total protein and be alert to the occurrence of adverse drug reactions. [ABSTRACT FROM AUTHOR]

Background: Exploration of novel combination mode of pyrotinib and chemotherapy for heavily pretreated HER2-positive metastatic breast cancer (MBC) and how to balance survival benefits and compliance are still urgent problems in clinical practice. The current single-arm prospective phase II study aimed to evaluate the efficacy and safety of pyrotinib in combination with metronomic oral etoposide in heavily pretreated HER2-positive MBC. Methods: HER2-positive MBC patients previously treated with trastuzumab were enrolled to receive oral pyrotinib 400 mg per day and metronomic oral etoposide 50 mg per day d1-21 every 28 days, until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). The secondary endpoints were objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), overall survival (OS), and safety. Results: 22 patients were enrolled with a median of 4 prior treatment regimens for MBC. During the follow-up of 20 evaluable patients, the median PFS was 9.0 months (95% CI, 7.6–10.4 months), and the median OS was 27.0 months (95%CI, 20.9–33.1 months). The ORR was 30% (6/20), the DCR was 80% (16/20), and the CBR was 65% (13/20). The most common grade 3 adverse events (AEs) included nausea (15%), vomiting (15%), diarrhea (5%), anemia (5%), and peripheral neuropathy (5%). No grade 4 or lethal AEs were observed. Conclusion: The combination of pyrotinib with metronomic oral etoposide has achieved promising clinical benefits in heavily pretreated HER2-positive MBC, with acceptable and manageable toxicity. Trial registration: Registry number: NCT03923179. Registered April 18, 2019. [ABSTRACT FROM AUTHOR]

Objective: Pyrotinb has been approved for the treatment of HER2-positive advanced or metastatic breast cancer in China. However, the plasma concentration of pyrotinb in different patients varies greatly, and in the course of treatment, if patients have intolerable adverse reactions, the drug dosage will be reduced or even stopped. This study set out to establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the determination of pyrotinb in human plasma, analyze the population pharmacokinetics (PPK) of pyrotinib and assess the influence of patient variables on PK of pyrotinib in patients with HER2 positive breast cancer. Method: An UPLC-MS/MS method was developed to measure pyrotinib in human plasma. Utilizing a gradient elution procedure and a Kinetex C18 column (2.1 mm × 100 mm, 1.7 µm), sample separation was accomplished in 5.5 min. Pyrotinb extraction via protein precipitation was used as a sample pre-treatment technique. In total, 50 patients provided 158 plasma samples, which were identified and used in the PPK investigation. The non-linear mixed-effects modeling (NONMEM) approach was used to assess the plasma concentrations and covariates information. For the final PPK model evaluation, external evaluation, non-parametric bootstrap, visual predictive check (VPC), and goodness-of-fit (GOF) were used. Results: The UPLC-MS/MS method for determining plasma concentration of pyrotinib in patients had good selectivity and linearity in the range of 1-1,000 ng/mL. Pyrotinib concentration profile in HER2-positive breast cancer patients was well described by a single-compartment PPK model with first-order absorption and elimination. The formulas for the final estimated values of overall parameters of CL/F and Vd/F and Ka are respectively: CL/F(L/h) x 88.8 × e(TP/67.2)×0.376, V/F(L) x 3940, KA(h-1) x 0.357FIXED. No dosage adjustment was advised, despite the possibility that the total protein levels could have a substantial impact on the apparent distribution volume of pyrotinib with limited magnitude. Conclusion: In this study, an UPLC-MS/MS method was established to determine the concentration of pyrotinib in human plasma. A population pharmacokinetic model of pyrotinib in HER2 positive breast cancer patients suggested that low serum total protein reduced the clearance rate of pyrotinib in patients. Clinical medical staff should pay attention to the liver function of patients with abnormal serum total protein and be alert to the occurrence of adverse drug reactions. [ABSTRACT FROM AUTHOR]

Background: We explored the efficacy and safety of inetetamab combined with sirolimus and chemotherapy for the treatment of human epidermal factor receptor 2 (HER2)‐positive metastatic breast cancer patients with abnormal activation of the PI3K/Akt/mTOR (PAM) pathway after trastuzumab treatment. Methods: For this prospective multicenter clinical study, HER2‐positive metastatic breast cancer patients with PAM pathway mutations confirmed by histology or peripheral blood genetic testing were enrolled from July 2021 to September 2022. Patients were randomly assigned to a trial or control group. The patients in the trial group received inetetamab combined with sirolimus and chemotherapy, while the control group patients received pyrotinib and chemotherapy. The RECIST v1.1 standard was used to evaluate efficacy. Descriptive statistics were used to summarize the clinicopathological features, and the Kaplan–Meier method was used to generate survival curves. The log‐rank test was used to compare progression‐free survival (PFS) between the two groups. Results: A total of 59 HER2‐positive metastatic breast cancer patients with abnormal activation of the PAM pathway were included, of which 37 received inetetamab combined with sirolimus and chemotherapy treatment and 22 received pyrotinib and chemotherapy treatment. The median PFS was 4.64 months in the inetetamab group and 5.69 months in the pyrotinib group, with no statistically significant difference (p = 0.507). The objective response rates were 27.3% for the inetetamab group and 29.4% for the pyrotinib group. The safety assessment indicated that the adverse event (AE) incidences were 86.1% (31/36) in the inetetamab group and 78.9 (15/19) in the pyrotinib group, with 9 (25%) and four (21.1%) Grade 3/4 AEs in the inetetamab and pyrotinib groups, respectively. Conclusions: For metastatic HER2‐positive breast cancer patients with abnormal PAM pathway activation and previous trastuzumab treatment, the combination of inetetamab with sirolimus and chemotherapy is equivalent to the combination of pyrotinib and chemotherapy. Therefore, this regimen could be a treatment option for PAM pathway‐activated metastatic HER2‐positive breast cancer patients. [ABSTRACT FROM AUTHOR]

Background: Inetetamab is a novel antibody targeting human epidermal growth factor receptor 2 (HER2) developed in China. Due to its optimized antibody-dependent cell-mediated cytotoxicity effect compared with trastuzumab, it has shown good efficacy and safety in the treatment of HER2-positive advanced breast cancer (ABC). Objectives: This study aimed to investigate the efficacy and safety of inetetamab combination therapy in the treatment of HER2-positive ABC in real-world clinical practice. Design: Retrospective study. Methods: A total of 133 patients with HER2-positive ABC who were treated with inetetamab-based regimens between March 2020 and January 2024 were retrospectively included in this study. The main endpoint was median progression-free survival (mPFS). The secondary endpoints included objective response rate (ORR), disease control rate (DCR), and safety. Results: The study included 133 HER2-positive ABC patients, and the median age was 55 years. The mPFS was 8.0 (6.7–9.3) months. The ORR was 50.4%, while the DCR was 88.7%. The mPFS for patients receiving inetetamab-based therapy as first to second, third to fourth, and later lines of metastatic treatment were 14.0, 7.0, and 6.0 months, respectively. Patients treated with inetetamab plus pyrotinib plus chemotherapy, especially with capecitabine, had the best outcomes (mPFS = 14.0 months). Multivariate analysis revealed that prior HER2-TKI treatment was significantly associated with worse PFS (hazard ratios 2.829, 95% confidence interval 1.265–6.328, p = 0.011). Subgroup analysis indicated that patients without visceral metastases had significantly better PFS (14.0 months vs 8.0 months, p = 0.003). The overall incidence of any grade adverse events (AEs) was 100%, with most being grades 1–2. Severe complications included neutropenia (37.6%) and leukopenia (33.1%). Conclusions: Inetetamab-based combination therapy shows promising efficacy and good safety in patients with HER2-positive ABC. It is one of the late-line treatment options for Chinese patients with HER2-positive ABC. [ABSTRACT FROM AUTHOR]

Abstract Background Exploration of novel combination mode of pyrotinib and chemotherapy for heavily pretreated HER2-positive metastatic breast cancer (MBC) and how to balance survival benefits and compliance are still urgent problems in clinical practice. The current single-arm prospective phase II study aimed to evaluate the efficacy and safety of pyrotinib in combination with metronomic oral etoposide in heavily pretreated HER2-positive MBC. Methods HER2-positive MBC patients previously treated with trastuzumab were enrolled to receive oral pyrotinib 400 mg per day and metronomic oral etoposide 50 mg per day d1-21 every 28 days, until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). The secondary endpoints were objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), overall survival (OS), and safety. Results 22 patients were enrolled with a median of 4 prior treatment regimens for MBC. During the follow-up of 20 evaluable patients, the median PFS was 9.0 months (95% CI, 7.6–10.4 months), and the median OS was 27.0 months (95%CI, 20.9–33.1 months). The ORR was 30% (6/20), the DCR was 80% (16/20), and the CBR was 65% (13/20). The most common grade 3 adverse events (AEs) included nausea (15%), vomiting (15%), diarrhea (5%), anemia (5%), and peripheral neuropathy (5%). No grade 4 or lethal AEs were observed. Conclusion The combination of pyrotinib with metronomic oral etoposide has achieved promising clinical benefits in heavily pretreated HER2-positive MBC, with acceptable and manageable toxicity. Trial registration Registry number: NCT03923179. Registered April 18, 2019.

Background: The efficacy of afatinib or pyrotinib has been demonstrated in HER2-positive advanced non-small cell lung cancer (NSCLC) patients; however, the efficacy of pyrotinib after afatinib progression has yet to be determined. Method: Patients with HER2 mutated advanced lung adenocarcinoma administered afatinib or pyrotinib monotherapy were enrolled. Those who received pyrotinib after afatinib were further analyzed to determine the efficacy and safety of pyrotinib after progression on afatinib. Survival curves were plotted with the Kaplan–Meier method. A swimming plot was used to describe the specific treatments. Additionally, patient-derived tumor organoids (PDTOs) were established from HER2-amplified NSCLC patient samples to investigate the antitumor activity of pyrotinib in HER2-amplified tumor cells in vitro. Results: A total of 99 patients were enrolled, 13 of whom were administered pyrotinib after progression on afatinib. No statistical difference in PFS of pyrotinib was observed between patients whether be treated after afatinib progression or not (6.7 months vs. 4.4 months, P = 0.817), thus indicating that progression on afatinib did not affect the efficacy of pyrotinib. Further analysis was conducted on the former patients, which comprising eight patients administered interval chemotherapy after progression on afatinib. Two patients achieved PR after pyrotinib treatment. No independent factors were found to influence the PFS of pyrotinib. PDTOs confirmed the anti-tumor activity of pyrotinib in NSCLC tumor cells with HER2 amplification. Conclusions: Progression after prior afatinib treatment does not influence the efficacy of pyrotinib treatment. Pyrotinib may be a salvage option for patients with HER2 mutation who have experienced progression on afatinib. [ABSTRACT FROM AUTHOR]

Abstract Background Human epidermal growth factor receptor 2 (HER2) plays an important role in the progression of multiple solid tumors and induces resistance to epidermal growth factor receptor (EGFR) target treatment. However, the expression status and the clinical significance of HER2 in oral squamous cell carcinoma (OSCC) is still controversial. Pyrotinib (PYR) is a promising novel EGFR/HER2 dual inhibitor, whose efficacy in OSCC has not been determined. Methods 57 locally advanced de novo OSCC patients were included in this study to investigate the relationship between the HER2 expression levels and the prognosis by the tissue microarray analysis (TMA). In vitro and in vivo experiments were performed to retrieve the efficacy of PYR in OSCC. The main downstream of HER2 was evaluated by western blotting in OSCC cell lines and xenograft tumors to explore the potential mechanism of PYR. Results This study revealed the primary tumor of OSCC had higher HER2 expression levels. Patients with HER2 overexpression had poor overall survival (P

Abstract In this study, we prepared a bionic nanosystem of trastuzumab-functionalized SK-BR-3 cell membrane hybrid liposome-coated pyrotinib (Ptb-M-Lip-Her) for the treatment of HER2-positive breast cancer. Transmission electron microscopy, dynamic light scattering, polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting were used to verify the successful preparation of Ptb-M-Lip-Her. In vitro drug release experiments proved that Ptb-M-Lip-Her had a sustained release effect. Cell uptake experiments and in vivo imaging experiments proved that Ptb-M-Lip-Her had good targeting ability to homologous tumor cells (SK-BR-3). The results of cell experiments such as MTT, flow cytometry, immunofluorescence staining and in vivo antitumor experiments showed that Ptb-M-Lip-Her could significantly promote apoptosis and inhibit the proliferation of SK-BR-3 cells. These results clearly indicated that Ptb-M-Lip-Her may be a promising biomimetic nanosystem for targeted therapy of HER2-positive breast cancer.

Metastatic colorectal cancer (mCRC) is characterized by significant phenotypic heterogeneity at the molecular level and presents a poor prognosis. Chemotherapy is commonly employed as the primary treatment option. Nevertheless, the advantages of chemotherapy are constrained, underscoring the critical necessity for novel treatment protocols aimed at enhancing patient outcomes. Human epidermal growth factor receptor 2 (HER2) has been recognized as a promising therapeutic target in mCRC. Pyrotinib, an innovative irreversible dual tyrosine kinase inhibitor targeting HER2, effectively inhibits cancer progression in various types of human cancers. Here, we present a case of a 39-year-old female with metastatic rectal cancer showing amplification of HER2. Despite resistance to multiple therapies, including trastuzumab and pertuzumab, the patient exhibited a remarkable therapeutic response to pyrotinib, tegafur combined with radiotherapy. This case provides evidence for the feasibility and potential efficacy of deploying pyrotinib in the salvage treatment of mCRC patients with HER2 amplification even though resistant to other anti-HER2 drugs. [ABSTRACT FROM AUTHOR]

Background: Human epidermal growth factor receptor 2 (HER2) plays an important role in the progression of multiple solid tumors and induces resistance to epidermal growth factor receptor (EGFR) target treatment. However, the expression status and the clinical significance of HER2 in oral squamous cell carcinoma (OSCC) is still controversial. Pyrotinib (PYR) is a promising novel EGFR/HER2 dual inhibitor, whose efficacy in OSCC has not been determined. Methods: 57 locally advanced de novo OSCC patients were included in this study to investigate the relationship between the HER2 expression levels and the prognosis by the tissue microarray analysis (TMA). In vitro and in vivo experiments were performed to retrieve the efficacy of PYR in OSCC. The main downstream of HER2 was evaluated by western blotting in OSCC cell lines and xenograft tumors to explore the potential mechanism of PYR. Results: This study revealed the primary tumor of OSCC had higher HER2 expression levels. Patients with HER2 overexpression had poor overall survival (P < 0.014) and poor disease free survival (P < 0.042). In vitro, PYR suppressed the proliferation, colony formation and migration of OSCC cells. It also promoted apoptosis of OSCC cells and induced cell cycle arrest. Furthermore, PYR was able to inhibit the occurrence and development of OSCC effectively in vivo. Western blotting revealed that PYR suppressed OSCC by inhibiting the phosphorylation of HER2, AKT and ERK. Conclusions: This study exhibited the anti-OSCC effects of PYR in vitro and in vivo, and demonstrated PYR inhibited OSCC cells by inducing apoptosis via the HER2/ AKT and ERK pathway. The result of this study also indicated locally advanced OSCC patients might benefit from HER2 assay and EGFR/HER2 dual inhibit treatment. [ABSTRACT FROM AUTHOR]

Objective: Pyrotinib, a new irreversible dual pan-human epidermal growth factor receptor 2 (HER2) receptor tyrosine kinase inhibitor blocking EGFR and HER2, has achieved a promising efficacy for advanced HER2-positive (HER2+) breast cancer. This study intended to further investigate the efficacy and safety of neoadjuvant pyrotinib and trastuzumab plus chemotherapy for HER2+ breast cancer treatment. Methods: Thirty-eight HER2+ breast cancer patients who received neoadjuvant pyrotinib and trastuzumab plus chemotherapy (docetaxel and carboplatin) were retrospectively reviewed. Clinical response by Response Evaluation Criteria in Solid Tumors (RECIST), pathological complete response (pCR), and adverse events data was retrieved. Results: According to the RECIST, the complete response rate was 0.0%, 10.5%, and 15.8% after second-cycle, fourth-cycle, and sixth-cycle therapy, respectively; whereas the objective response rate was 76.3%, 92.1%, and 100.0%, accordingly. The total pCR (tpCR) rate was 52.6%, the pCR rate of the breast was also 52.6%, and the pCR rate of lymph nodes was 86.8%. The tpCR rate was lower in patients with HER2 immunohistochemistry (IHC)++ and amplification by fluorescent in situ hybridization (FISH) than in those with HER2 IHC+++ (14.3% vs. 61.3%, p = 0.024), which was also lower in patients with Ki-67 expression ≥30% than in those with Ki-67 expression <30% (40.0% vs. 76.9%, p = 0.031). The common adverse events included diarrhea (84.2%), anemia (73.7%), nausea and vomiting (63.2%), fatigue (50.0%), hypomagnesemia (44.7%), leukopenia (42.1%), thrombocytopenia (39.5%), elevated transaminase (36.8%), and pruritus (31.6%). Conclusions: Pyrotinib and trastuzumab plus chemotherapy serve as an acceptable neoadjuvant regimen exhibiting good efficacy and tolerance in HER2+ breast cancer patients, while further large-scale validation is warranted. [ABSTRACT FROM AUTHOR]

Extramammary Paget disease (EMPD) is a rare cutaneous intraepithelial adenocarcinoma, which is mostly distributed in areas with sweat gland cells and mainly occurs in the anogenital skin of women. The male genital tract involvement is extremely rare and often occurs with other malignant tumors. Paget's disease in the scrotum with sweat gland carcinoma is even rarer. In the first report of scrotal endocrine sweat gland carcinoma associated with Paget disease by Saidi et al. in 1997, no more than 50 cases have been reported in the relevant research worldwide. Early EMPD combined with sweat gland carcinoma is mainly surgical treatment, and there is no standard treatment plan for advanced EMPD with sweat gland carcinoma. Previous article has reported that chemotherapy such as paclitaxel, fluorouracil, platinum, and vinblastine and molecular targeted therapy based on the genetic test results of patients have certain efficacy. Here, we report a 79-year-old male case diagnosed with human epidermal growth factor receptor 2 (HER-2) overexpression, which was effectively controlled by chemotherapy and anti--HER-2 treatment such as pyrotinib. [ABSTRACT FROM AUTHOR]

Objectives: HER2 is an infrequently mutated driver gene in non‐small cell lung cancer (NSCLC). At present, there has been no comprehensive large‐scale clinical study to establish the optimal first‐line treatment strategy for advanced lung adenocarcinoma (LUAD) with HER2‐Mutant. Besides that, the effectiveness and safety of pyrotinib, a pan‐HER inhibitor, in the context of NSCLC are still undergoing investigation. Materials and Methods: In this study, we conducted a retrospective data collection of HER2‐Mutated advanced LUAD who received first‐line treatment and pyrotinib between May 2014 and June 2023. Patients treated with chemotherapy, chemotherapy + immune checkpoint inhibitors (ICIs), chemotherapy + bevacizumab and pyrotinib in first‐line treatment. Furthermore, we collected data on the efficacy and safety of pyrotinib in these patients after disease progression. The main endpoint of the study was progression‐free survival (PFS). Results: In the final analysis, 89 patients were included in the first‐line cohort and 30 patients were included in the pyrotinib cohort. In the first‐line treatment cohort, chemotherapy + ICIs, chemotherapy + bevacizumab, and pyrotinib exhibited notable survival benefits compared to chemotherapy (median PFS: 9.87 vs. 7.77 vs. 7.10 vs. 5.40 months, p‐value < 0.05). Furthermore, patients with a first‐line treatment PFS of less than 6 months may potentially benefit from subsequent treatment with pyrotinib (median PFS: 7.467 vs. 3.000, p‐value = 0.0490). Conclusions: In the first‐line treatment of HER2‐Mutant LUAD, regimens involving combinations like chemotherapy + ICIs, chemotherapy + bevacizumab, and pyrotinib may confer enhanced survival advantages compared to chemotherapy. Nevertheless, no significant distinctions were observed among these three treatment strategies, underscoring the imperative to identify biomarkers for the discerning selection of suitable therapeutic modalities. Moreover, patients with suboptimal response to first‐line treatment may potentially derive more benefit from pyrotinib. [ABSTRACT FROM AUTHOR]

In this study, we prepared a bionic nanosystem of trastuzumab-functionalized SK-BR-3 cell membrane hybrid liposome-coated pyrotinib (Ptb-M-Lip-Her) for the treatment of HER2-positive breast cancer. Transmission electron microscopy, dynamic light scattering, polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting were used to verify the successful preparation of Ptb-M-Lip-Her. In vitro drug release experiments proved that Ptb-M-Lip-Her had a sustained release effect. Cell uptake experiments and in vivo imaging experiments proved that Ptb-M-Lip-Her had good targeting ability to homologous tumor cells (SK-BR-3). The results of cell experiments such as MTT, flow cytometry, immunofluorescence staining and in vivo antitumor experiments showed that Ptb-M-Lip-Her could significantly promote apoptosis and inhibit the proliferation of SK-BR-3 cells. These results clearly indicated that Ptb-M-Lip-Her may be a promising biomimetic nanosystem for targeted therapy of HER2-positive breast cancer. [ABSTRACT FROM AUTHOR]

Background: The combination of dual‐targeted human epidermal growth factor receptor 2 (HER2) therapy and chemotherapy is the standard first‐line regimen for recurrent/metastatic breast cancer (mBC). However, the toxicity of such combination therapy can lead to some patients being unable to tolerate adverse events or bear treatment costs. As a novel irreversible pan‐ErbB receptor TKI (pyrotinib), can the dual oral administration of pyrotinib plus capetabine (PyroC) provide first‐line survival benefits and serve as a more affordable treatment option? Methods: This real‐world retrospective study included patients diagnosed with HER2‐positive mBC who received PyroC as a first‐line treatment at West China Hospital between May 2018 and July 2023. The survival data and toxicity profiles were reported in this study. Results: A total of 64 patients received PyroC as first‐line therapy. The median progression‐free survival (PFS) was 19.6 months (95% CI 15.0–27.2), while overall survival (OS) has not yet been reached. Kaplan–Meier analysis indicated that age (≥60, p = 0.03) and metastasis sites (p = 0.004) were related to poor efficacy of PyroC, while there was no relationship between effectiveness and menstrual status, hormone receptor (HR) status or previous treatment with anti‐HER2 therapy. Furthermore, the objective response rate (ORR) and disease control rate (DCR) were 79.7% and 98.4%, respectively. Of the patients, 78.1% reported treatment‐related adverse events (TRAEs). The predominant adverse events were diarrhea (n = 46, 71.9%) and hand‐foot syndrome (n = 10, 15.6%). Conclusion: The dual oral administration regimen (PyroC) has a promising ORR or PFS in HER2‐positive mBC patients, with an acceptable safety profile and convenience. [ABSTRACT FROM AUTHOR]

Summary: Background: The PHILA study suggests that pyrotinib, trastuzumab, and docetaxel significantly improved progression-free survival (PFS) compared with placebo, trastuzumab, and docetaxel in patients with untreated HER2-positive metastatic breast cancer. In this study, we aimed to investigate the synergistic mechanisms of pyrotinib plus trastuzumab and provide further insights for the PHILA trial. Methods: The in vitro activity of combination treatments was assessed through cell biological and biochemical experiments. The in vivo efficacy was evaluated in cell-derived xenografts, a TUBO tumour model, and one clinical case. Next-generation sequencing was performed on circulating tumour DNA (ctDNA) from patients in the PHILA trial. Findings: The combination of pyrotinib and trastuzumab more effectively inhibited cell growth than pyrotinib or trastuzumab alone in models of HER2-dependent breast cancer. It potentiated membrane HER2 ubiquitination and downregulation, which resulted in a comprehensive blockade of the HER2 signalling pathway. The pyrotinib-altered membrane HER2 levels had no significant effect on trastuzumab-mediated antibody-dependent cell-mediated cytotoxicity (ADCC). We further validated the synergistic mechanisms in TUBO tumours and one clinical case, rather than models of HCC1954 cells harbouring the PIK3CA H1047R mutation. Similarly, in our centre cohort of the PHILA study, patients with genetic alterations in the HER2 signalling cascade had significantly shorter median PFS than individuals with the wild-type pathway. Interpretation: Our findings underscore the robust synergy between pyrotinib and trastuzumab in overcoming HER2 dependency and provide a rationale for pyrotinib, trastuzumab, and docetaxel as one of the optimal choices for patients with untreated HER2-positive metastatic breast cancer, who are dependent on the HER2 signalling cascade. Funding: This work was supported by the National Key Research and Development Program of China (2021YFF1201300), the National Natural Science Foundation of China (82172875), the CAMS Innovation Fund for Medical Sciences (CIFMS) (2022-I2M-2-001), and the Joint Innovative Fund of Beijing Natural Science Foundation and Changping District (L234004).

Summary: Background: The phase 2 PERMEATE study has shown the antitumor activity and safety of pyrotinib plus capecitabine in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer and brain metastases. In this report, survival results were updated with extended follow-up. Methods: Between January 29, 2019 and July 10, 2020, adult patients with HER2-positive metastatic breast cancer who had radiotherapy-naïve brain metastases (cohort A, n = 59) or progressive disease after radiotherapy (cohort B, n = 19) were enrolled and received pyrotinib (400 mg once daily) and capecitabine (1000 mg/m2 twice daily on days 1–14 of each 21-day cycle) until disease progression or unacceptable toxicity. Secondary endpoints progression-free survival (PFS) and overall survival (OS) were updated, and post-hoc central nervous system (CNS)-PFS was analyzed. This study is registered with ClinicalTrials.gov (NCT03691051). Findings: As of February 2, 2023, the median follow-up duration was 30.9 months (interquartile range, 16.1–39.8). Median PFS was 10.9 months (95% confidence interval [CI], 7.6–14.6) in cohort A and 5.7 months (95% CI, 3.4–11.5) in cohort B. Median OS was 35.9 months (95% CI, 24.4-not reached) in cohort A and 30.6 months (95% CI, 12.6–33.3) in cohort B. Median CNS-PFS was 13.6 months (95% CI, 9.0–15.8) in cohort A and 5.7 months (95% CI, 3.4–11.5) in cohort B. Median OS was 34.1 months (95% CI, 21.7-not reached) for 14 patients with intracranial progression only in cohort A who restarted pyrotinib plus capecitabine after local radiotherapy. Interpretation: These data support further validation in a randomized controlled trial for the assessment of pyrotinib in combination with capecitabine as systemic therapy for patients with HER2-positive breast cancer and brain metastases. Funding: National Cancer Center Climbing Foundation Key Project of China, Jiangsu Hengrui Pharmaceuticals.

Abstract Background We explored the efficacy and safety of inetetamab combined with sirolimus and chemotherapy for the treatment of human epidermal factor receptor 2 (HER2)‐positive metastatic breast cancer patients with abnormal activation of the PI3K/Akt/mTOR (PAM) pathway after trastuzumab treatment. Methods For this prospective multicenter clinical study, HER2‐positive metastatic breast cancer patients with PAM pathway mutations confirmed by histology or peripheral blood genetic testing were enrolled from July 2021 to September 2022. Patients were randomly assigned to a trial or control group. The patients in the trial group received inetetamab combined with sirolimus and chemotherapy, while the control group patients received pyrotinib and chemotherapy. The RECIST v1.1 standard was used to evaluate efficacy. Descriptive statistics were used to summarize the clinicopathological features, and the Kaplan–Meier method was used to generate survival curves. The log‐rank test was used to compare progression‐free survival (PFS) between the two groups. Results A total of 59 HER2‐positive metastatic breast cancer patients with abnormal activation of the PAM pathway were included, of which 37 received inetetamab combined with sirolimus and chemotherapy treatment and 22 received pyrotinib and chemotherapy treatment. The median PFS was 4.64 months in the inetetamab group and 5.69 months in the pyrotinib group, with no statistically significant difference (p = 0.507). The objective response rates were 27.3% for the inetetamab group and 29.4% for the pyrotinib group. The safety assessment indicated that the adverse event (AE) incidences were 86.1% (31/36) in the inetetamab group and 78.9 (15/19) in the pyrotinib group, with 9 (25%) and four (21.1%) Grade 3/4 AEs in the inetetamab and pyrotinib groups, respectively. Conclusions For metastatic HER2‐positive breast cancer patients with abnormal PAM pathway activation and previous trastuzumab treatment, the combination of inetetamab with sirolimus and chemotherapy is equivalent to the combination of pyrotinib and chemotherapy. Therefore, this regimen could be a treatment option for PAM pathway‐activated metastatic HER2‐positive breast cancer patients.

Objective: Pyrotinib is a novel irreversible tyrosine kinase inhibitor that has shown efficacy for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). This study explored the efficacy and safety of pyrotinib in the treatment of HER2-positive MBC patients in the real world. Methods: From September 2018 to February 2022, 137 female patients with HER2-positive MBC treated in this center were enrolled in this study. The follow-up period ended on January 12, 2023. The primary endpoint of this study was progression-free survival (PFS). Overall survival (OS), objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), central nervous system (CNS)-PFS, CNS-ORR, CNS-CBR, CNS-DCR, and adverse event (AE) were the secondary endpoints. Results: The ORR, DCR and CBR were 41.98 % (55/131), 87.79 % (115/131) and 44.27 % (58/131) in this cohort, respectively. The median PFS for this cohort was 10.37 months [95 % confidence interval (CI): 9.205-11.535] and the median OS was 37.53 months (not reached). Univariate and multivariate analyses showed that trastuzumab sensitivity was an independent predictor of improved PFS [hazard ratio (HR): 0.579 (0.371-0.904, p=0.016)] and improved OS [0.410 (0.213-0.790, p=0.008)]. Patients treated with a pyrotinib-based regimen as second-line and third-or-post-line therapy had poorer PFS [second-line: 3.315 (1.832-6.000, p

Qingqing Gu, Mingzhi Zhu, Yanyan Wang, Yuanting Gu The Second Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of ChinaCorrespondence: Yuanting Gu; Yanyan Wang, The Second Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China, Tel +86-371-66913114, Fax +86-371-66964992, Email guyuanting2009@163.com; fccwangyy22@zzu.edu.cnPurpose: To evaluate the efficacy and safety of a pyrotinib-based therapy for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) in the real world.Methods: Clinical data of 218 patients with HER2-positive MBC who received a pyrotinib-based therapy from January 2020 to March 2023 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed.Results: Finally, 195 patients were included in the efficacy cohort. The median progression-free survival (PFS) in the total population is 12.4 months (95% CI, 9.8– 15.0 months). More than half of the patients in the efficacy cohort received pyrotinib mono-targeted therapy (103 cases, 52.8%). Among the remaining patients, 74 (37.9%) patients chose a combined trastuzumab-targeted therapy and 17 (8.7%) chose to combine inetetamab. Median PFS in the pyrotinib group vs pyrotinib plus trastuzumab group was 10.5 months vs 20.1 months (P< 0.001). The median PFS of primary trastuzumab resistance population reached to 20.1 months in pyrotinib plus trastuzumab group. Double-targets’ advantage was also observed in the brain metastases subgroup (17.9 months vs 10.0 months, P=0.386). The patients who received pyrotinib plus inetetamab as second and higher-line treatment reached a median PFS of 7.9 months (95% CI, 4.0– 11.8 months). Forty-one (19.8%) of 207 patients included in the safety cohort experienced grade 3 or higher diarrhea, the most common adverse event in safety analysis, and no adverse event-related deaths.Conclusion: The combination of pyrotinib and trastuzumab demonstrated promising efficacy in the treatment of HER2-positive metastatic breast cancer, including those who had primary resistance to trastuzumab and brain metastases. Pyrotinib plus trastuzumab is expected to be a potent option in the first-line. Additionally, the concurrent administration of pyrotinib and inetetamab could be an alternative to consider in the second and higher-line treatment for metastatic breast cancer. The adverse reactions of pyrotinib were tolerable in general.Keywords: pyrotinib, HER2, metastatic breast cancer, trastuzumab, inetetamab

Congcong Wang,1,&ast; Jinyu Xiang,1,&ast; Qingyu Zhang,1 Jing Li,1 Yanqing Liu,2 Jiannan Liu1 1Department of Oncology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shangdong, 264000, People’s Republic of China; 2Department Brest Surgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shangdong, 264000, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Jiannan Liu, Department of Oncology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 Yuhuangding East Road, Yantai, 264000, People’s Republic of China, Email ljnwcc@163.com Yanqing Liu, Department Brest Surgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 Yuhuangding East Road, Yantai, 264000, People’s Republic of China, Email liuyanqing927@163.comAim: Approximately 50% of patients diagnosed with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (BC) are estimated to develop brain metastases (BMs). This study was aimed to assess the intracranial efficacy and survival benefits of pyrotinib and capecitabine combination therapy in the treatment of BMs in patients with HER2-positive BC.Methods: A total of 56 HER2-positive BC patients with BMs were treated with 400 mg pyrotinib once daily along with 1000 mg/m2 capecitabine twice daily for 14 days in 21-day cycles. The patients were allocated into three cohorts: (1) Cohort A composed of patients with newly diagnosed BMs without prior local radiotherapy, (2) Cohort B included patients with stable post-local radiotherapy, and (3) Cohort C composed of patients with progression following local radiotherapy. The primary endpoint was the intracranial objective response rate (CNS-ORR), while secondary endpoints included intracranial disease control rate (CNS-DCR), progression-free survival (PFS), overall survival (OS), safety, as well as QoL.Results: The observed CNS-ORR CNS-ORR of 72.73% (95% CI 51.85– 86.85%) in cohort A, 55% (95% CI 34.21– 74.18%) in cohort B, and 42.86% (95% CI 21.38– 67.41%) in cohort C. The mPFS was 11 months, 8.4 months, and 5.2 months in cohorts A, B, and C, respectively. Diarrhea, accounting for 23.21% of all the patients, was the most common grade 3/4 adverse event related with treatments (6/22 [27.3%] in cohort A, 4/20 [20.0%] in cohort B, and 3/14 [21.4%] in cohort C). However, there were no deaths related with treatments observed. Importantly, the QoL was efficiently maintained throughout the treatment duration.Conclusion: Pyrotinib and capecitabine combination therapy proved significant effectiveness as well as tolerability in treating HER2-positive BC with BMs, yielding satisfactory results, especially in radiotherapy-naive population.Keywords: breast cancer, brain metastases, pyrotinib, capecitabine, HER2, radiotherapy

In this study, the trastuzumab-functionalized SK-BR-3 cell membrane-wrapped mesoporous silica nanoparticles loaded with pyrotinib (Tra-CM-MSN-PYR) were prepared for targeted therapy of HER2-positive breast cancer. Transmission electron microscopy (TEM) characterization showed that MSN had a spherical morphology with mesoporous channels and that the structure of Tra-CM-MSN was a cell membrane (CM) layer successfully coated on the surface of MSN. A cellular uptake assay demonstrated that FITC-labeled Tra-CM-MSN were taken up by SK-BR-3 breast cancer cells, which illustrated that Tra-CM-MSN had good targeting ability compared with CM-MSN and MSN. In vivo imaging experiments demonstrated significant accumulation of FITC-labeled Tra-CM-MSN in tumor tissues, further proving that Tra-CM-MSN have superior targeting properties. Cell apoptosis experiments suggested that Tra-CM-MSN-PYR significantly inhibited the proliferation of SK-BR-3 breast cancer cells. The results of in vivo animal experiments also showed that Tra-CM-MSN-PYR significantly inhibited tumor growth. These results indicate that Tra-CM-MSN-PYR has potential application as a targeted therapy for HER2-positive breast cancer in the future.

Objective: It has been observed that the prognosis of patients with HER2‐positive metastatic breast cancer has improved significantly with HER2‐targeted agents. However, there is still a lack of evidence regarding first‐line anti‐HER2 treatment options for patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer. Besides, there are no reliable markers that can predict the efficacy of anti‐HER2 treatment in these patients. Methods: Patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer were enrolled. Pyrotinib plus albumin‐bound paclitaxel were used as first‐line treatment. The primary endpoint was the objective response rate (ORR). The safety profile was also assessed. In order to explore predictive biomarkers using Olink technology, blood samples were collected dynamically. Results: From December 2019 to August 2023, the first stage of the study involved 27 eligible patients. It has not yet reached the median PFS despite the median follow‐up being 17.8 months. Efficacy evaluation showed that the ORR was 92.6%, and the DCR was 100%. Adverse events of grade 3 or higher included diarrhoea (29.6%), leukopenia (11.1%), neutropenia (25.9%), oral mucositis (3.7%), and hand‐foot syndrome (3.7%). Toll‐like receptor 3 (TLR3) and Proto‐oncogene tyrosine‐protein kinase receptor (RET) were proteins with significant relevance to PFS in these patients. Conclusions: This study demonstrates that pyrotinib plus albumin‐bound paclitaxel as a first‐line treatment regimen shows good efficacy and manageable safety for patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer. Besides, a significant association was identified between the expression levels of TLR3 and RET and the PFS in patients. [ABSTRACT FROM AUTHOR]

There remains an unmet need for targeted therapies against advanced non‐small‐cell lung cancer (NSCLC) with HER2 mutations. To improve the antitumor activity of single anti‐HER2 agent, this prospective, single‐arm clinical trial (NCT05016544) examined the safety profile and efficacy of anti‐HER2 antibody inetetamab and pan‐HER TKI pyrotinib in HER2‐posivite advanced NSCLC patients. Enrolled patients received inetetamab every 3 weeks and pyrotinib once per day (pyrotinib, dose‐escalation part, 240 mg, 320 mg; dose‐expansion part, 320 mg). Primary endpoints were dose‐limiting toxicity (DLT) dosage and safety. Secondary endpoints included progression‐free survival (PFS), objective response rate (ORR), and disease control rate (DCR). A total of 48 patients were enrolled. During the dose‐escalation period, no DLT occurred. Diarrhea was the most commonly reported treatment‐related adverse event (TRAE). Grade 3 TRAEs occurred in seven patients. The median PFS (mPFS) was 5.5 months [95% confidence interval (CI): 4.4–8.6 months]. The confirmed ORR and DCR reached 25% (11/44) and 84.1% (37/44), respectively. Responses were shown in patients with distinct HER2 aberrations. In summary, inetetamab in combination with pyrotinib demonstrated acceptable safety and antitumor activity among patients with advanced HER2‐mutant NSCLC. [ABSTRACT FROM AUTHOR]

Anti‐HER2 (human epidermal growth factor receptor 2) therapies significantly increase the overall survival of patients with HER2‐positive breast cancer. Unfortunately, a large fraction of patients may develop primary or acquired resistance. Further, a multidrug combination used to prevent this in the clinic places a significant burden on patients. To address this issue, this work develops a nanotherapeutic platform that incorporates bimetallic gold‐silver hollow nanoshells (AuAg HNSs) with exceptional near‐infrared (NIR) absorption capability, the small‐molecule tyrosine kinase inhibitor pyrotinib (PYR), and Herceptin (HCT). This platform realizes targeted delivery of multiple therapeutic effects, including chemo‐and photothermal activities, oxidative stress, and immune response. In vitro assays reveal that the HCT‐modified nanoparticles exhibit specific recognition ability and effective internalization by cells. The released PYR inhibit cell proliferation by downregulating HER2 and its associated pathways. NIR laser application induces a photothermal effect and tumor cell apoptosis, whereas an intracellular reactive oxygen species burst amplifies oxidative stress and triggers cancer cell ferroptosis. Importantly, this multimodal therapy also promotes the upregulation of genes related to TNF and NF‐κB signaling pathways, enhancing immune activation and immunogenic cell death. In vivo studies confirm a significant reduction in tumor volume after treatment, substantiating the potential effectiveness of these nanocarriers. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

AbstractThis study aimed to compare the efficacy of pyrotinib, trastuzumab combined with chemotherapy with different lines therapy in human epidermal growth factor receptor 2- (HER2-) positive advanced breast cancer (ABC) and analyze the factors affecting the prognosis. A total of 84 patients with median age of 49 year-old. The mPFS of patients receiving first-line pyrotinib plus trastuzumab and chemotherapy was the longest (11 months) compared with second- and third line patients (p = 0.106). The objective response rate (ORR) and disease control rate (DCR) of the total population were 33.3% and 82.1% respectively. Subgroup analysis suggested that using pyrotinib plus trastuzumab and Albumin-bound paclitaxel was not inferior to combine with Vinorelbine in regards of PFS. Histological grade (OR: 0.233[0.069 ∼ 0.781], p = 0.018) and tumor location (OR: 0.286[0.087 ∼ 0.942], p = 0.040) were independent factors influencing the ORR. Multivariate cox analysis showed that Ki-67 was independently associated with increased risk of progression (HR: 1.843[1.044-3.254], p = 0.035). The most common adverse events were diarrhea (17.9%) and neutropenia (11.9%). In the first-, second- and third-line treatment, pyrotinib plus trastuzumab and chemotherapy is effective and safe. Pyrotinib and trastuzumab combined with Albumin-bound paclitaxel may be a potential ideal treatment plan for HER2-positive advanced breast cancer. [ABSTRACT FROM AUTHOR]

Triple‐positive breast cancer (TPBC) poorly responds to current standard neoadjuvant therapy (trastuzumab plus pertuzumab and chemotherapy). Our previous MUKDEN 01 study showed a promising total pathological complete response (tpCR) rate of 30.4% with neoadjuvant pyrotinib (pan‐human epidermal growth factor receptor tyrosine kinase inhibitor) plus dalpiciclib (cyclin‐dependent kinase 4/6 inhibitor) and letrozole, but the efficacy remains suboptimal. This pilot study (NCT05228951) explored adding trastuzumab to this triplet neoadjuvant regimen in patients with stage II–III TPBC. The primary endpoint was tpCR (ypT0/is, ypN0) rate. Between February 2022 and June 2022, 12 patients were enrolled, and seven (58%; 95% confidence interval [CI], 27.7%–84.8%) patients achieved tpCR. The rate of residual cancer burden (RCB) 0–I was 75% (95% CI, 46.8%–91.1%). The objective response rate (ORR) was 92% (95% CI, 64.6%–98.5%). Mean Ki‐67 level was significantly reduced from 45.0% (95% CI, 19.5%–70.5%) at baseline to 17.2% (95% CI, 0.7%–33.7%) after neoadjuvant therapy (p = 0.03). The most common grade 3 adverse events were diarrhea (four [33%]) and decreased neutrophil count (three [25%]). No grade 4 adverse events or treatment‐related deaths occurred. This four‐drug neoadjuvant regimen shows promising pathological response with an acceptable safety profile in patients with TPBC. A randomized controlled trial (NCT05638594) of this regimen is being conducted. [ABSTRACT FROM AUTHOR]

BackgroudHuman epithelial growth factor receptor 2 (HER2) amplification is an important mechanism of acquired resistance to anti-epidermal growth factor receptor (EGFR) therapy in non-small cell lung cancer (NSCLC) patients. For patients with both EGFR mutation and HER2 amplification, there is currently no unified standard treatment, and further exploration is needed on how to choose the therapy.Methods and resultsA female NSCLC patient developed bone and brain metastases 14 and 42 months after radical surgery, respectively. The second genetic sequencing detected EGFR L858R mutation and HER2 amplification, and therefore initiated treatment with almonertinib and pyrotinib. The patient achieved partial remission and did not show any further progression during the follow-up period.ConclusionFor NSCLC patients with both EGFR mutation and HER2 amplification, the combination of almonertinib and pyrotinib is a valuable therapy that can continuously reduce tumor burden and achieve long-term survival.

Abstract Objectives HER2 is an infrequently mutated driver gene in non‐small cell lung cancer (NSCLC). At present, there has been no comprehensive large‐scale clinical study to establish the optimal first‐line treatment strategy for advanced lung adenocarcinoma (LUAD) with HER2‐Mutant. Besides that, the effectiveness and safety of pyrotinib, a pan‐HER inhibitor, in the context of NSCLC are still undergoing investigation. Materials and Methods In this study, we conducted a retrospective data collection of HER2‐Mutated advanced LUAD who received first‐line treatment and pyrotinib between May 2014 and June 2023. Patients treated with chemotherapy, chemotherapy + immune checkpoint inhibitors (ICIs), chemotherapy + bevacizumab and pyrotinib in first‐line treatment. Furthermore, we collected data on the efficacy and safety of pyrotinib in these patients after disease progression. The main endpoint of the study was progression‐free survival (PFS). Results In the final analysis, 89 patients were included in the first‐line cohort and 30 patients were included in the pyrotinib cohort. In the first‐line treatment cohort, chemotherapy + ICIs, chemotherapy + bevacizumab, and pyrotinib exhibited notable survival benefits compared to chemotherapy (median PFS: 9.87 vs. 7.77 vs. 7.10 vs. 5.40 months, p‐value

Abstract Background The combination of dual‐targeted human epidermal growth factor receptor 2 (HER2) therapy and chemotherapy is the standard first‐line regimen for recurrent/metastatic breast cancer (mBC). However, the toxicity of such combination therapy can lead to some patients being unable to tolerate adverse events or bear treatment costs. As a novel irreversible pan‐ErbB receptor TKI (pyrotinib), can the dual oral administration of pyrotinib plus capetabine (PyroC) provide first‐line survival benefits and serve as a more affordable treatment option? Methods This real‐world retrospective study included patients diagnosed with HER2‐positive mBC who received PyroC as a first‐line treatment at West China Hospital between May 2018 and July 2023. The survival data and toxicity profiles were reported in this study. Results A total of 64 patients received PyroC as first‐line therapy. The median progression‐free survival (PFS) was 19.6 months (95% CI 15.0–27.2), while overall survival (OS) has not yet been reached. Kaplan–Meier analysis indicated that age (≥60, p = 0.03) and metastasis sites (p = 0.004) were related to poor efficacy of PyroC, while there was no relationship between effectiveness and menstrual status, hormone receptor (HR) status or previous treatment with anti‐HER2 therapy. Furthermore, the objective response rate (ORR) and disease control rate (DCR) were 79.7% and 98.4%, respectively. Of the patients, 78.1% reported treatment‐related adverse events (TRAEs). The predominant adverse events were diarrhea (n = 46, 71.9%) and hand‐foot syndrome (n = 10, 15.6%). Conclusion The dual oral administration regimen (PyroC) has a promising ORR or PFS in HER2‐positive mBC patients, with an acceptable safety profile and convenience.

Background: Human epidermal growth factor receptor 2 (HER2)-targeted agents have significantly improved the outcomes of patients with HER2-positive breast cancer; however, a large proportion of patients still develop resistance to trastuzumab. In this study, we investigated the efficacy and safety of inetetamab, another anti-HER2 antibody, combined with pyrotinib and oral vinorelbine in patients with HER2-positive advanced breast cancer so as to provide new ideas for the treatment. Methods: In this prospective, single-arm, phase 2 trial, patients with HER2-positive advanced breast cancer with disease progression after trastuzumab were recruited. Patients received a combination of inetetamab (loading dose of 8 mg/kg and subsequent doses of 6 mg/kg intravenously once every 3 weeks), pyrotinib (400 mg orally once daily), and vinorelbine (60 mg/m2 orally once weekly) until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). The secondary endpoints included objective response rate (ORR), overall survival (OS), disease control rate (DCR), and safety. Results: Between February 13, 2022 and December 25, 2022, 30 patients were screened and enrolled in this study. The median age of the patients at enrollment was 54 years, 12 patients (40.0 %) had hormone-receptor-positive disease and 23 patients (76.7 %) had visceral metastasis. The median PFS was 8.63 months (95 % confidence interval [CI] 4.15–13.12 months). The median OS was not reached. The ORR was 53.3 % (16/30) and the DCR was 96.7 % (29/30). The most common Grade III/IV adverse events were leukopenia (n = 5, 16.7 %), neutropenia (n = 4, 13.3 %), and diarrhea (n = 3, 10 %). No treatment-related serious adverse events or deaths occurred. Conclusions: The combination regimen of inetetamab, pyrotinib, and oral vinorelbine showed encouraging efficacy and favorable safety in patients with HER2-positive advanced breast cancer and could be considered as an alternative treatment option for the patients. Trial registration: No.NCT05823623; https://www.clinicaltrials.gov/.

Abstract Background This prospective study aims to investigate the efficacy and safety of pyrotinib (P) combined with 4 cycles of epirubicin and cyclophosphamide followed by 4 cycles of taxane and trastuzumab (P + EC-TH) regimen as neoadjuvant therapy for human epidermal growth factor receptor 2 (HER2) positive breast cancer and to investigate the predictive value of p53, p63, and epidermal growth factor receptor (EGFR) status for neoadjuvant efficacy. Methods A total of 138 HER2-positive breast cancer patients who received neoadjuvant therapy and underwent surgery were included. Case group: 55 patients received P + EC-TH regimen. Control group: 83 patients received EC-TH regimen. The chi-square test, Fisher’s exact test, and logistic regression analysis were applied. The primary endpoint was total pathologic complete response (tpCR), and the secondary endpoints were breast pathologic complete response (bpCR), overall response rate (ORR), and adverse events (AEs). Results In the case group, the tpCR rate was 63.64% (35/55), the bpCR rate was 69.09% (38/55), and the ORR was 100.00% (55/55). In the control group, the tpCR rate was 39.76% (33/83), the bpCR rate was 44.58% (37/83), and the ORR was 95.18% (79/83). The case group had significantly higher tpCR and bpCR rates than those of the control group (P 0.05). The tpCR was associated with the status of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR), and the patients with any negative ER, PR, AR, or combined, were more likely to achieve tpCR than those with positive results (P

Background Pyrotinib is currently approved for the treatment of HER2-positive advanced breast cancer in China. Data on the overall survival (OS) and efficacy in patients with brain metastasis (BM) remain scarce. This study evaluated the effectiveness of pyrotinib in a real-world setting, especially in patients with BM. Methods We reviewed patients with metastatic breast cancer treated with pyrotinib-based therapy between June 2018 and June 2022. Progression-free survival (PFS), OS, objective response rate, and safety were analyzed following the administration of pyrotinib. Results A total of 239 patients were included. The median PFS in patients who received pyrotinib-based therapy as first-line (15/239), second-line (115/239), or third-or-higher-line (109/239) treatment was 14.00, 9.33, and 8.20 months, respectively, and the median OS was not reached, 29.07 and 22.23 months, respectively. The median PFS in patients who pretreated with trastuzumab (214/239), trastuzumab plus pertuzumab (22/239), lapatinib (68/239), or trastuzumab emtansine (14/239) was 9.33, 6.87, 7.20, and 7.20 months, respectively. In 61 patients with BM, the median PFS was 7.50 months, the median central nervous system (CNS)-PFS was 11.17 months, and the median OS was 21.27 months. Furthermore, 19 patients with concomitant brain radiotherapy tended to achieve a longer OS than 42 patients without radiation (34.17 vs. 20.70 months, P  = .112). Conclusions Long-term outcomes of pyrotinib-based therapy are promising for patients with HER2-positive metastatic breast cancer in real world and in patients with BM, regardless of the treatment lines and prior anti-HER2 therapies. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: This prospective study aims to investigate the efficacy and safety of pyrotinib (P) combined with 4 cycles of epirubicin and cyclophosphamide followed by 4 cycles of taxane and trastuzumab (P + EC-TH) regimen as neoadjuvant therapy for human epidermal growth factor receptor 2 (HER2) positive breast cancer and to investigate the predictive value of p53, p63, and epidermal growth factor receptor (EGFR) status for neoadjuvant efficacy. Methods: A total of 138 HER2-positive breast cancer patients who received neoadjuvant therapy and underwent surgery were included. Case group: 55 patients received P + EC-TH regimen. Control group: 83 patients received EC-TH regimen. The chi-square test, Fisher's exact test, and logistic regression analysis were applied. The primary endpoint was total pathologic complete response (tpCR), and the secondary endpoints were breast pathologic complete response (bpCR), overall response rate (ORR), and adverse events (AEs). Results: In the case group, the tpCR rate was 63.64% (35/55), the bpCR rate was 69.09% (38/55), and the ORR was 100.00% (55/55). In the control group, the tpCR rate was 39.76% (33/83), the bpCR rate was 44.58% (37/83), and the ORR was 95.18% (79/83). The case group had significantly higher tpCR and bpCR rates than those of the control group (P < 0.05), but there was no significant difference in ORR (P > 0.05). The tpCR was associated with the status of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR), and the patients with any negative ER, PR, AR, or combined, were more likely to achieve tpCR than those with positive results (P < 0.05). The p53-positive patients were more likely to achieve tpCR and bpCR than p53-negative patients (P < 0.05). The incidence of hypokalemia and diarrhea in the case group was higher than that in the control group (P < 0.05). The AEs developed were all manageable, and no treatment-related death occurred. Conclusion: The efficacy and safety of the P + EC-TH regimen were verified by this study. The HER2-positive breast cancer patients treated with the EC-TH neoadjuvant regimen were more likely to achieve tpCR or bpCR if pyrotinib was administered simultaneously. [ABSTRACT FROM AUTHOR]

Background: Pyrotinib, a novel irreversible pan-HER tyrosine kinase inhibitor, has been approved for the treatment of HER2-positive metastatic breast cancer in China. The aim of this study was to evaluate the efficacy and safety of pyrotinib in advanced nonsmall cell lung cancer (NSCLC) patients with HER2 alterations in real-world practice. Materials and Methods: A retrospective analysis of advanced NSCLC with HER2 mutations or amplifications who received pyrotinib-based treatment at the Qilu Hospital in Shandong University was performed. The primary end points were objective response rate and safety. The secondary end points were progression-free survival, disease control rate, and overall survival. Results: Twenty three eligible patients from a single center were enrolled between June 2019 and March 2023; among them, 21 had HER2 mutation and two harbored HER2 amplification. Evaluation of the efficacy in 21 patients revealed an objective response rate of 28.6% (6/21; 95% confidence interval [CI]: 7.5%-49.6%) and disease control rate of 85.7% (18/21). The median progression-free survival and overall survival were 7.7 months (95% CI: 6.07-9.33) and 20.8 months (95% CI: 8.42-33.18), respectively. The most common adverse events (AEs) included diarrhea (n = 14, 60.9%), nausea (n = 5, 21.7%), and liver dysfunction (n = 5, 21.7%). Seven patients (7/23, 30.4%) had grade 3-4 AE; no grade 5 AE was observed. Furthermore, one patient (1/23, 4.3%) experienced dose withdrawal and two (2/23, 8.7%) presented with dose reduction symptoms. Conclusion: Pyrotinib-based therapy showed promising antitumor activity and acceptable safety in advanced NSCLC patients with HER2 alterations. [ABSTRACT FROM AUTHOR]

The objective of this multicenter, single‐arm trial (ChiCTR1900022293) was to explore the efficacy and safety of neoadjuvant therapy with epirubicin, cyclophosphamide, and pyrotinib followed by docetaxel, trastuzumab, and pyrotinib (ECPy‐THPy) in the treatment of patients with stage II–III HER2‐positive breast cancer. The present study enrolled patients with stage II–III HER2‐positive breast cancer. Epirubicin and cyclophosphamide were administrated for four 21‐day cycles, followed by four cycles of docetaxel and trastuzumab. Pyrotinib was taken orally once per day throughout the treatment period. The primary endpoint was total pathological complete response (tpCR, ypT0/is ypN0) rate in the modified intention‐to‐treat (mITT) population. In total, 175 patients were included. The tpCR rate was 68.6% (95% CI, 60.7–75.8%), while the objective response rate was 89.1%. In the post‐hoc subgroup analysis, no association between clinical characteristics and the tpCR rate was observed. The most common grade ≥3 adverse events were diarrhea (54.3%), followed by white blood cell count decreased (5.1%), and neutrophil count decreased (4.6%). In conclusion, the neoadjuvant regimen with ECPy‐THPy showed promising pathological response and clinical benefits with an acceptable safety profile in patients with stage II–III HER2‐positive breast cancer. [ABSTRACT FROM AUTHOR]

Abstract Objective It has been observed that the prognosis of patients with HER2‐positive metastatic breast cancer has improved significantly with HER2‐targeted agents. However, there is still a lack of evidence regarding first‐line anti‐HER2 treatment options for patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer. Besides, there are no reliable markers that can predict the efficacy of anti‐HER2 treatment in these patients. Methods Patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer were enrolled. Pyrotinib plus albumin‐bound paclitaxel were used as first‐line treatment. The primary endpoint was the objective response rate (ORR). The safety profile was also assessed. In order to explore predictive biomarkers using Olink technology, blood samples were collected dynamically. Results From December 2019 to August 2023, the first stage of the study involved 27 eligible patients. It has not yet reached the median PFS despite the median follow‐up being 17.8 months. Efficacy evaluation showed that the ORR was 92.6%, and the DCR was 100%. Adverse events of grade 3 or higher included diarrhoea (29.6%), leukopenia (11.1%), neutropenia (25.9%), oral mucositis (3.7%), and hand‐foot syndrome (3.7%). Toll‐like receptor 3 (TLR3) and Proto‐oncogene tyrosine‐protein kinase receptor (RET) were proteins with significant relevance to PFS in these patients. Conclusions This study demonstrates that pyrotinib plus albumin‐bound paclitaxel as a first‐line treatment regimen shows good efficacy and manageable safety for patients who have received adjuvant and/or neoadjuvant trastuzumab for HER2‐positive metastatic breast cancer. Besides, a significant association was identified between the expression levels of TLR3 and RET and the PFS in patients.

Abstract There remains an unmet need for targeted therapies against advanced non‐small‐cell lung cancer (NSCLC) with HER2 mutations. To improve the antitumor activity of single anti‐HER2 agent, this prospective, single‐arm clinical trial (NCT05016544) examined the safety profile and efficacy of anti‐HER2 antibody inetetamab and pan‐HER TKI pyrotinib in HER2‐posivite advanced NSCLC patients. Enrolled patients received inetetamab every 3 weeks and pyrotinib once per day (pyrotinib, dose‐escalation part, 240 mg, 320 mg; dose‐expansion part, 320 mg). Primary endpoints were dose‐limiting toxicity (DLT) dosage and safety. Secondary endpoints included progression‐free survival (PFS), objective response rate (ORR), and disease control rate (DCR). A total of 48 patients were enrolled. During the dose‐escalation period, no DLT occurred. Diarrhea was the most commonly reported treatment‐related adverse event (TRAE). Grade 3 TRAEs occurred in seven patients. The median PFS (mPFS) was 5.5 months [95% confidence interval (CI): 4.4–8.6 months]. The confirmed ORR and DCR reached 25% (11/44) and 84.1% (37/44), respectively. Responses were shown in patients with distinct HER2 aberrations. In summary, inetetamab in combination with pyrotinib demonstrated acceptable safety and antitumor activity among patients with advanced HER2‐mutant NSCLC.

Abstract Anti‐HER2 (human epidermal growth factor receptor 2) therapies significantly increase the overall survival of patients with HER2‐positive breast cancer. Unfortunately, a large fraction of patients may develop primary or acquired resistance. Further, a multidrug combination used to prevent this in the clinic places a significant burden on patients. To address this issue, this work develops a nanotherapeutic platform that incorporates bimetallic gold‐silver hollow nanoshells (AuAg HNSs) with exceptional near‐infrared (NIR) absorption capability, the small‐molecule tyrosine kinase inhibitor pyrotinib (PYR), and Herceptin (HCT). This platform realizes targeted delivery of multiple therapeutic effects, including chemo‐and photothermal activities, oxidative stress, and immune response. In vitro assays reveal that the HCT‐modified nanoparticles exhibit specific recognition ability and effective internalization by cells. The released PYR inhibit cell proliferation by downregulating HER2 and its associated pathways. NIR laser application induces a photothermal effect and tumor cell apoptosis, whereas an intracellular reactive oxygen species burst amplifies oxidative stress and triggers cancer cell ferroptosis. Importantly, this multimodal therapy also promotes the upregulation of genes related to TNF and NF‐κB signaling pathways, enhancing immune activation and immunogenic cell death. In vivo studies confirm a significant reduction in tumor volume after treatment, substantiating the potential effectiveness of these nanocarriers.

Abstract Triple‐positive breast cancer (TPBC) poorly responds to current standard neoadjuvant therapy (trastuzumab plus pertuzumab and chemotherapy). Our previous MUKDEN 01 study showed a promising total pathological complete response (tpCR) rate of 30.4% with neoadjuvant pyrotinib (pan‐human epidermal growth factor receptor tyrosine kinase inhibitor) plus dalpiciclib (cyclin‐dependent kinase 4/6 inhibitor) and letrozole, but the efficacy remains suboptimal. This pilot study (NCT05228951) explored adding trastuzumab to this triplet neoadjuvant regimen in patients with stage II–III TPBC. The primary endpoint was tpCR (ypT0/is, ypN0) rate. Between February 2022 and June 2022, 12 patients were enrolled, and seven (58%; 95% confidence interval [CI], 27.7%–84.8%) patients achieved tpCR. The rate of residual cancer burden (RCB) 0–I was 75% (95% CI, 46.8%–91.1%). The objective response rate (ORR) was 92% (95% CI, 64.6%–98.5%). Mean Ki‐67 level was significantly reduced from 45.0% (95% CI, 19.5%–70.5%) at baseline to 17.2% (95% CI, 0.7%–33.7%) after neoadjuvant therapy (p = 0.03). The most common grade 3 adverse events were diarrhea (four [33%]) and decreased neutrophil count (three [25%]). No grade 4 adverse events or treatment‐related deaths occurred. This four‐drug neoadjuvant regimen shows promising pathological response with an acceptable safety profile in patients with TPBC. A randomized controlled trial (NCT05638594) of this regimen is being conducted.

Abstract Background Although some targeted therapies have been shown to be effective in treating HER2‐altered non‐small cell lung cancer (NSCLC), the survival demands have not yet been met due to the high cost and limited availability. This study aimed to assess the effectiveness and safety of pyrotinib plus antiangiogenic agents, including apatinib, anlotinib, and bevacizumab, in previously treated patients with HER2‐altered advanced NSCLC. Methods In this retrospective real‐world study, patients with HER2‐altered NSCLC who received pyrotinib plus antiangiogenic agents as a second‐ or later‐line treatment between November 2015 and January 2022 were reviewed. The objective response rate (ORR), disease control rate (DCR), progression‐free survival (PFS), overall survival (OS), and safety profiles of patients were analyzed. Results A total of 107 patients were included in the analysis, of which 59 patients (55.1%) had received at least two lines of prior chemotherapy or tyrosine kinase inhibitors. Most of them (87.9%) were identified as harboring HER2 exon 20 insertions. At the data cutoff date (May 13, 2022), the ORR, DCR, median PFS, and median OS were 19.6% (21/107), 94.4% (101/107), 7.13 months (95% confidence interval [CI]: 6.26–8.01), and 19.50 months (95% CI: 12.83–26.17), respectively. There was no difference in the PFS between patients receiving apatinib or anlotinib/bevacizumab (median PFS, 7.13 vs. 6.27 months, hazard ratio [HR] = 1.49, 95% CI: 0.87–2.54, p = 0.15). The most frequent grade 3 or higher treatment‐related adverse events was diarrhea (17.6%), followed by hypertension (11.0%) and nausea (3.3%). No treatment‐related death occurred. Conclusion In this study, pyrotinib plus antiangiogenic agents demonstrated promising efficacy and were tolerable in HER2‐altered NSCLC patients.

Jie Huang,1,&ast; Wenqiang Zhu,1,&ast; Qiangzhi Duan,2,&ast; Chaomang Zhu,1 Xueling Shi,1 Hongyu Zhao,1 Peng Cai,1 Duojie Li1 1Department of Radiotherapy, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233000, People’s Republic of China; 2Department of Radiotherapy, The 2nd Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233000, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Duojie Li, Department of Radiotherapy, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233000, People’s Republic of China, Tel/Fax +86-139-5633-2626, Email liduojie@163.comPurpose: To explore the efficacy and safety of pyrotinib combined with different radiotherapy modes in human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) patients with brain metastasis (BM).Patients and Methods: This study is a retrospective analysis of patients diagnosed with BM who underwent treatment with pyrotinib between November 2018 and April 2023. A total of 66 patients were administered radiotherapy in conjunction with pyrotinib (Group A), while 26 patients received pyrotinib as a standalone treatment (Group B). Within Group A, 18 patients underwent conventional fractionated radiotherapy (2Gy/F), while 48 patients received hyperfractionated radiotherapy (HFRT) (≥ 3Gy/F). The primary endpoints were intracranial progression-free survival (IC-PFS) and overall survival (OS). The secondary endpoints were objective response rate (ORR) and clinical benefit rate (CBR).Results: The ORR of Group A was 54.5% (36/66), while the ORR of Group B was 34.6% (9/26) (P= 0.047). The CBR of Group A was 89.4% (59/66) and that of Group B was 69.2% (18/26) (P= 0.041). The IC-PFS between Group A and Group B were 12 months and 8 months, respectively (P< 0.001), and the OS were 20 months and 16 months, respectively (P= 0.065). In Group A, the IC-PFS and OS between the conventional fractionation radiotherapy group and the HFRT group were 10 months and 12 months, respectively (P= 0.001) and 16 months and 24 months, respectively (P< 0.001). No serious adverse reactions were observed in Group A and Group B.Conclusion: For HER2-positive BC patients with BM, it is recommended to adopt the treatment mode of HFRT combined with pyrotinib, which can improve the local control and survival of patients.Keywords: breast cancer, human epidermal growth factor receptor type 2, brain metastasis, pyrotinib, radiation therapy, hyperfractionated radiotherapy

Abstract Human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) is a highly aggressive subtype associated with poor prognosis. The advent of HER2-targeted drugs, including monoclonal antibodies, tyrosine-kinase inhibitors (TKIs) and antibody–drug conjugates, has yielded improved prognosis for patients. Compared with widely used monoclonal antibodies, small-molecule TKIs have unique advantages including oral administration and favorable penetration of blood–brain barrier for brain metastatic BC, and reduced cardiotoxicity. Pyrotinib is an irreversible TKI of the pan-ErbB receptor, and has recently been shown to be clinically effective for the treatment of HER2-positive BC in metastatic and neoadjuvant settings. This review highlights the development on the application of pyrotinib-based therapeutic approaches in the clinical settings of HER2-positive BC.

Abstract Background Patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer and primary resistance to trastuzumab have a poor clinical outcome and lack good evidence to inform clinical decision. This study investigated the efficacy and safety of pyrotinib plus capecitabine in this population. Methods This phase 2 trial was conducted at 16 sites in China. Patients received oral pyrotinib 400 mg once daily and capecitabine 1000 mg/m2 twice a day on days 1–14 of each 21-day cycle until disease progression or intolerable toxicity. The primary endpoint was investigator-assessed progression-free survival (PFS). Results Between June 2019 and September 2021, 100 patients were enrolled with a median age of 51 years (range, 24–69). All patients had been treated with trastuzumab and 21 (21.0%) patients had prior use of pertuzumab. As of August 31, 2022, the median follow-up duration was 20.1 months (range, 1.3–38.2). The median PFS was 11.8 months (95% confidence interval [CI], 8.4–15.1), which crossed the pre-specified efficacy boundary of 8.0 months. The objective response rate was 70.0% (70/100), with a median duration of response of 13.8 months (95% CI, 10.2–19.3). The disease control rate was 87.0% (87/100). The median overall survival was not reached. The most common grade ≥ 3 treatment-emergent adverse event was diarrhea (24 [24.0%]). No treatment-related deaths occurred. Conclusions Pyrotinib plus capecitabine can be considered to be a treatment option in HER2-positive advanced breast cancer patients who have shown primary resistance to trastuzumab. Even in the era of modern anti-HER2 treatments, this clinical setting warrants more investigations to meet unmet needs. Trial registration ClinicalTrials.gov, NCT04001621. Retrospectively registered on June 28, 2019.

Abstract Background Human epidermal growth factor receptor 2 (HER2) targeted therapy combined with endocrine therapy has been recommended as an alternative treatment strategy for patients with hormone receptor (HR)-positive, HER2-positive metastatic breast cancer (MBC). This study aimed to evaluate the role of pyrotinib, an oral pan-HER irreversible tyrosine kinase inhibitor, in combination with letrozole for patients with HR-positive, HER2-positive MBC. Methods In this multi-center, phase II trial, HR-positive and HER2-positive MBC patients who were not previously treated for metastasis disease were enrolled. Patients received daily oral pyrotinib 400 mg and letrozole 2.5 mg until disease progression, unacceptable toxicity, or withdrawal of consent. The primary endpoint was the clinical benefit rate (CBR) assessed by an investigator according to the Response Evaluation Criteria in Solid Tumors version 1.1. Results From November 2019 to December 2021, 53 patients were enrolled and received pyrotinib plus letrozole. As of August 2022, the median follow-up duration was 11.6 months (95% confidence interval [CI], 8.7–14.0 months). The CBR was 71.7% (95% CI, 57.7–83.2%), and the objective response rate was 64.2% (95% CI, 49.8–76.9%). The median progression-free survival was 13.7 months (95% CI, 10.7–18.7 months). The most common treatment-related adverse event of grade 3 or higher was diarrhea (18.9%). No treatment-related deaths were reported, and one patient experienced treatment discontinuation due to adverse event. Conclusions Our preliminary results suggested that pyrotinib plus letrozole is feasible for the first-line treatment of patients with HR-positive and HER2-positive MBC, with manageable toxicities. Trial registration ClinicalTrials.gov, NCT04407988.

Abstract Background Non-small cell lung cancer (NSCLC) with HER2 mutation has entered into the era of targeted therapy. However, both anti-HER2 antibody–drug conjugates (ADCs) and tyrosine kinase inhibitors (TKIs) showed moderate objective response rate (ORR) and median progression-free survival (PFS). The aim of this study was to investigate the molecular features of responders to pyrotinib in advanced NSCLC with HER2 mutation. Methods Patients from our two previous phase II trials were pooled analyzed. Their circulating tumor DNA (ctDNA) were detected by next-generation sequencing (NGS) panels, and the correlation with the efficacy of pyrotinib was investigated. Results This pooled analysis included 75 patients, and 50 of them with baseline plasma samples were finally enrolled with a median age of 57 years old. The overall ORR and median PFS were 28% and 7.0 months respectively. Biomarker analysis showed that 5 patients were ctDNA nonshedding. Patients with TP53 wild type were significantly associated with higher disease control rate (97.1%vs. 68.8%, p = 0.010), PFS (median 8.4 vs. 2.8 months, p = 0.001) and overall survival (OS, median 26.7 vs. 10.4 months, p

Abstract The objective of this multicenter, single‐arm trial (ChiCTR1900022293) was to explore the efficacy and safety of neoadjuvant therapy with epirubicin, cyclophosphamide, and pyrotinib followed by docetaxel, trastuzumab, and pyrotinib (ECPy‐THPy) in the treatment of patients with stage II–III HER2‐positive breast cancer. The present study enrolled patients with stage II–III HER2‐positive breast cancer. Epirubicin and cyclophosphamide were administrated for four 21‐day cycles, followed by four cycles of docetaxel and trastuzumab. Pyrotinib was taken orally once per day throughout the treatment period. The primary endpoint was total pathological complete response (tpCR, ypT0/is ypN0) rate in the modified intention‐to‐treat (mITT) population. In total, 175 patients were included. The tpCR rate was 68.6% (95% CI, 60.7–75.8%), while the objective response rate was 89.1%. In the post‐hoc subgroup analysis, no association between clinical characteristics and the tpCR rate was observed. The most common grade ≥3 adverse events were diarrhea (54.3%), followed by white blood cell count decreased (5.1%), and neutrophil count decreased (4.6%). In conclusion, the neoadjuvant regimen with ECPy‐THPy showed promising pathological response and clinical benefits with an acceptable safety profile in patients with stage II–III HER2‐positive breast cancer.