Search

Background: HER2(+) gastric cancer (GC) can benefit from trastuzumab. However, the impact of additional trastuzumab in preoperative treatment on immune cells remains largely unknown., Methods: In cohort I, immune cells were detected by immunohistochemistry in 1321 patients. Then 88 HER2(+) patients received preoperative therapy were collected as cohort II. Immune cell profiles and changes were analyzed in paired pre- and post-operative specimens using multiple immunohistochemistry staining., Results: In the treatment-naive GC patients (n = 1002), CD3+ and CD8+ T cell infiltration was significantly lower in the HER2(+) GC patients together with higher FoxP3+ T cells compared with HER2(-). However, FoxP3+ T and CD20+ B cell infiltration was significantly higher in HER2(+) GC after neoadjuvant chemotherapy (n = 319). The trastuzumab-exposed group had higher CD8+ T and lower FoxP3+ T cell infiltration and CD8+ T cell was even more significant in responders. Additionally, tertiary lymphoid structure (TLS) density increased in invasion margin of residual tumors. Patients with lower TLS in the tumor core or lower FoxP3+ T cells had better overall survival in the trastuzumab-exposed group., Conclusion: Addition of trastuzumab modulates the immune microenvironment, suggesting the potential mechanism of the favorable outcome of anti-HER2 therapy and providing a theoretical rationale for the combinational immunotherapy in resectable HER2(+) GC patients., (© 2024. The Author(s).)

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. The APHINITY trial (ClinicalTrials.gov identifier: NCT01358877) previously demonstrated that pertuzumab added to adjuvant trastuzumab and chemotherapy improved invasive disease-free survival (iDFS) for patients with early human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC). Here, we report the preplanned third interim analysis of overall survival (OS) and a descriptive updated iDFS analysis with 8.4 years of median follow-up of 4,804 patients in the intent-to-treat population. The 8-year OS was 92.7% in the pertuzumab versus 92.0% in the placebo group (hazard ratio [HR], 0.83 [95% CI, 0.68 to 1.02]; P = .078, above the 0.006 significance threshold). The HR was 0.80 [95% CI 0.63 to 1.00] in the node-positive cohort and 0.99 [95% CI, 0.64 to 1.55] in the node-negative cohort. Updated results of 8-year iDFS in the node-positive cohort showed an absolute improvement of 4.9% favoring pertuzumab (86.1% v 81.2%; HR, 0.72 [95% CI, 0.60 to 0.87]). The node-negative cohort did well without adding pertuzumab (8-year iDFS and OS in the placebo group were 93.3% and 96.4%, respectively). The iDFS benefit was seen in the hormone receptor-negative (HR, 0.82 [95% CI, 0.64 to 1.06]) and HR+ cohorts (HR of 0.75 [95% CI, 0.61 to 0.92]). Despite improvement in overall iDFS, the addition of pertuzumab did not improve OS at this third interim analysis.

Purpose: Patients with HER2-positive breast cancer brain metastases have few effective systemic therapy options. In a prior study, pertuzumab with high-dose trastuzumab demonstrated a high clinical benefit rate (CBR) in the central nervous system (CNS) in patients with brain metastases. The current trial evaluated whether the addition of atezolizumab to this regimen would produce further improvements in CNS response., Patients and Methods: This was a single-arm, multicenter, phase II trial of atezolizumab, pertuzumab, and high-dose trastuzumab for patients with HER2-positive breast cancer brain metastases. Participants received atezolizumab 1,200 mg i.v. every 3 weeks, pertuzumab (loading dosage 840 mg i.v., then 420 mg i.v. every 3 weeks), and high-dose trastuzumab (6 mg/kg i.v. weekly for 24 weeks, then 6 mg/kg i.v. every 3 weeks). The primary endpoint was CNS overall response rate per Response Assessment in Neuro-Oncology Brain Metastases criteria. Key secondary endpoints included CBR, overall survival, and safety and tolerability of the combination., Results: Among 19 enrolled participants, two had a confirmed intracranial partial response for a CNS overall response rate of 10.5% (90% confidence interval, 1.9%-29.6%). The study did not meet the prespecified efficacy threshold and was terminated early. The CBR was 42.1% at 18 weeks and 31.6% at 24 weeks. Seven patients (36.8%) required a dose delay or hold, and the most frequent any-grade adverse events were diarrhea (26.3%) and fatigue (26.3%)., Conclusions: The addition of atezolizumab to pertuzumab plus high-dose trastuzumab does not result in improved CNS responses in patients with HER2-positive breast cancer brain metastases., (©2024 The Authors; Published by the American Association for Cancer Research.)

Purpose: Long-term outcomes of patients with stage I human epidermal growth factor receptor 2 (HER2)-positive breast cancer receiving adjuvant trastuzumab emtansine (T-DM1) remain undefined, and prognostic predictors represent an unmet need., Methods: In the ATEMPT phase II trial, patients with stage I centrally confirmed HER2-positive breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for 1 year or paclitaxel plus trastuzumab (TH). Coprimary objectives were to compare the incidence of clinically relevant toxicities between arms and to evaluate invasive disease-free survival (iDFS) with T-DM1. Correlative analyses included the HER2DX genomic tool, multiomic evaluations of HER2 heterogeneity, and predictors of thrombocytopenia., Results: After a median follow-up of 5.8 years, 11 iDFS events were observed in the T-DM1 arm, consistent with a 5-year iDFS of 97.0% (95% CI, 95.2 to 98.7). At 5 years, the recurrence-free interval (RFI) was 98.3% (95% CI, 97.0 to 99.7), the overall survival was 97.8% (95% CI, 96.3 to 99.3), and the breast cancer-specific survival was 99.4% (95% CI, 98.6 to 100). Comparable iDFS was observed with T-DM1 irrespective of tumor size, hormone receptor status, centrally determined HER2 immunohistochemical score, and receipt of T-DM1 for more or less than 6 months. Although ATEMPT was not powered for this end point, the 5-year iDFS in the TH arm was 91.1%. Among patients with sufficient tissue for HER2DX testing (n = 187), 5-year outcomes significantly differed according to HER2DX risk score, with better RFI (98.1% v 81.8%, hazard ratio [HR], 0.10, P = .01) and iDFS (96.3% v 81.8%, HR, 0.20, P = .047) among patients with HER2DX low-risk versus high-risk tumors, respectively., Conclusion: Adjuvant T-DM1 for 1 year leads to outstanding long-term outcomes for patients with stage I HER2-positive breast cancer. A high HER2DX risk score predicted a higher risk of recurrence in ATEMPT.

Trastuzumab is a potent targeted therapy drug for HER2-positive cancer patients. A comprehensive understanding of trastuzumab's mechanism of action, pharmacokinetic (PK) parameters, and steady-state exposure in different treatment regimens and administration routes is essential for a thorough evaluation of the drug's safety and effectiveness. Due to the distinctive pharmacokinetics, indications, and administration methods of trastuzumab, this understanding becomes crucial. Drug exposure can be assessed by measuring trastuzumab's peak concentration, trough concentration, or area under the curve through assays like enzyme-linked immunosorbent assay (ELISA) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). The dose-response (D-R) and exposure-response (E-R) relationships establish the correlation between drug dosage/exposure and the therapeutic effect and safety. Additionally, various covariates such as body weight, aspartate transaminase, and albumin levels can influence drug exposure. This review provides a comprehensive overview of trastuzumab's mechanism of action, data on steady-state concentration and PK parameters under multiple administration routes and indications, discussions on factors influencing PK parameters, and evaluations of the effectiveness and safety of E-R and D-R in diverse HER2-positive cancer patients., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Until recently, the available human receptor epidermal growth factor 2 (HER2) targeted agents were ineffective for treating patients with HER2-low expressing breast cancer (defined as immunohistochemical expression of 1+ or 2+ without amplification). The development of novel and potent HER2-directed antibody-drug conjugates, affective at treating HER2-low expressing breast cancers, have changed the way we think about HER2-low expression and expanded the treatment options for many patients with advanced disease., Areas Covered: In this review, we summarize the current management of HER2-low breast cancer and commonly encountered challenges such as treatment sequencing and toxicity management., Expert Opinion: trastuzumab deruxtecan (T-DXd) is a treatment option for patients with advanced, HER2-low breast cancer, irrespective of the hormone receptor status. The current optimal place in treatment algorithms is after the first line of chemotherapy, both in HR-positive and triple-negative breast cancer; however, other agents are available in this setting and risks and benefits for each should be considered in shared decision making. Up to 10-15% of patients receiving T-DXd develop interstitial lung disease. Patient and clinician education are key to safely implement T-DXd in clinical practice.

Background: Gastric cancer is the fifth most common cancer and the fourth most common cause of cancer death worldwide, yet the prognosis of advanced disease remains poor., Methods: This was a randomized, double-blinded, phase 2 trial (ClinicalTrials.gov: NCT04908813). Patients with locally advanced/metastatic HER2-positive gastric/gastroesophageal junction cancer and no prior systemic antitumor therapy were randomized 1:1:1 to 25 mg/kg HLX22 (a novel anti-HER2 antibody) + HLX02 (trastuzumab biosimilar) + oxaliplatin and capecitabine (XELOX) (group A), 15 mg/kg HLX22 + HLX02 + XELOX (group B), or placebo + HLX02 + XELOX (group C) in 3-week cycles. Primary endpoints were progression-free survival (PFS) and objective response rate (ORR) assessed by independent radiological review committee (IRRC)., Findings: Between November 29, 2021, and June 6, 2022, 82 patients were screened; 53 were randomized to group A (n = 18), B (n = 17), and C (n = 18). With 14.3 months of median follow-up, IRRC-assessed median PFS was prolonged with the addition of HLX22 (A vs. C, 15.1 vs. 8.2 months, hazard ratio [HR] 0.5 [95% confidence interval (CI) 0.17-1.27]; B vs. C, not reached vs. 8.2 months, HR 0.1 [95% CI 0.04-0.52]). Confirmed ORR was comparable among groups (A vs. B vs. C, 77.8% vs. 82.4% vs. 88.9%). Treatment-related adverse events (TRAEs) were observed in 18 (100%), 16 (94.1%), and 17 (94.4%) patients, respectively. One (5.6%) patient in group C reported a grade 5 TRAE., Conclusions: Adding HLX22 to HLX02 and XELOX prolonged PFS and enhanced antitumor response in the first-line treatment of HER2-positive gastric cancer, with manageable safety., Funding: Shanghai Henlius Biotech, Inc., Competing Interests: Declaration of interests F.Y., H.Y., Jing Li, Q.W., and J. Zhu are employees of Shanghai Henlius Biotech, Inc., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: SHR-A1811 is an antibody-drug conjugate composed of an anti-human epidermal growth factor receptor 2 (HER2) antibody trastuzumab, a cleavable linker, and a topoisomerase I inhibitor payload. We assessed the safety, tolerability, antitumor activity, and pharmacokinetics of SHR-A1811 in heavily pretreated HER2-expressing or mutated advanced solid tumors., Methods: This global, multi-center, first-in-human, phase I trial was conducted at 33 centers. Patients who had HER2-expressing or mutated unresectable, advanced, or metastatic solid tumors and were refractory or intolerant to standard therapies were enrolled. SHR-A1811 was administered intravenously at doses ranging from 1.0 to 8.0 mg/kg once every 3 weeks. The primary end points were dose-limiting toxicity, safety, and the recommended phase II dose., Results: From September 7, 2020, to February 27, 2023, 307 patients who had undergone a median of three (IQR, 2-5) previous treatment regimens in the metastatic setting received SHR-A1811 treatment. As of data cutoff (February 28, 2023), one patient from the 6.4 mg/kg group experienced dose-limiting toxicities (pancytopenia and colitis). The most common grade 3 or higher adverse events (AEs) included decreased neutrophil count (119 [38.8%]) and decreased WBC count (70 [22.8%]). Interstitial lung disease occurred in only eight (2.6%) patients. Serious AEs and deaths occurred in 70 (22.8%) and 13 (4.2%) patients, respectively. SHR-A1811 led to objective responses in 59.9% (184/307) of all patients, 76.3% (90/118) of HER2-positive breast cancer, 60.4% (55/91) of HER2 low-expressing breast cancer, and 45.9% (39/85 with evaluable tumor responses) of the 98 nonbreast tumors., Conclusion: SHR-A1811 exhibited acceptable tolerability, promising antitumor activity, and a favorable pharmacokinetic profile in heavily pretreated advanced solid tumors. The recommended phase II dose of 4.8 or 6.4 mg/kg was selected for various tumor types.

Introduction: To evaluate the efficacy, safety, pharmacokinetics (PK), and immunogenicity of ZRC-3277 (pertuzumab biosimilar) with Perjeta® (pertuzumab) in previously untreated patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC)., Patients and Methods: This phase III, multicenter, double-blind study across 38 sites in India randomized (1:1) patients with HER2-positive MBC in either the ZRC-3277 or Perjeta® group. Both groups also received trastuzumab and docetaxel. Of 268 enrolled patients, mITT population had 243 patients (119 and 124 in the ZRC-3277 and Perjeta® groups, respectively). The primary objective was to compare the between-group objective response rate (ORR) after 6 cycles of treatment. ORR was determined by evaluating scans of computed tomography or magnetic resonance imaging following Response Evaluation Criteria in Solid Tumor (RECIST 1.1). Two-sided 95% confidence interval (95% CI) for the difference in ORR was determined to evaluate the noninferiority of ZRC-3277 to Perjeta®. The secondary outcomes included the assessment of PK, immunogenicity, and safety between the 2 groups., Results: In the mITT population, 104 (87.39%) and 114 (91.94%) participants achieved the ORR in the ZRC-3277 and Perjeta® groups, respectively. For predefined -15% noninferiority margin, obtained 2-sided 95% CIs (-12.19%, 3.11%) for the difference in ORR (-4.55%) between the 2 groups demonstrated the noninferiority of ZRC-3277 to Perjeta®. PK, immunogenicity, and safety were not significantly different between the 2 groups., Conclusion: Efficacy, PK, immunogenicity, and safety profiles of ZRC-3277 was found to be similar to those of Perjeta®., Competing Interests: Disclosure Deven Parmar is an employee of Zydus Therapeutics Inc, USA, whereas Maulik Doshi and Rahul Shrivastava are employees of Zydus Lifesciences Ltd. All other authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To evaluate the efficacy and safety of the combination of olaparib plus trastuzumab in patients with HER2-positive advanced breast cancer (ABC) and germinal BRCA mutations (gBRCAm)., Methods: OPHELIA (NCT03931551) was a single-arm, open-label, phase 2 clinical trial. Patients aged ≥18 years diagnosed with HER2-positive ABC with germinal deleterious mutations in BRCA1 or BRCA2 who had received at least one prior systemic regimen for advanced disease were enrolled. Patients received olaparib plus trastuzumab until disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was investigator-assessed clinical benefit rate for at least 24 weeks as per RECIST v.1.1. Key secondary endpoints included overall response rate (ORR) and safety profile., Results: A total of 68 pre-treated HER2-positive ABC patients were screened. Due to slow accrual the trial was stopped after enrolling 5 patients instead of the planned sample size of 20. Four patients achieved clinical benefit (80.0 %, 95 % CI; 28.4-99.5, p < 0.001) and the primary endpoint was met. The ORR was 60.0 % (95 % CI; 14.7-94.7), including one complete response. Four (80.0 %) patients experienced at least one treatment-related treatment-emergent adverse event (TEAE). Most TEAEs were grade 1 or 2. There were no treatment-related deaths and no new safety signals were identified., Conclusions: This study suggests that the combination of olaparib plus trastuzumab may be effective and safe in pre-treated patients with HER2-positive gBRCAm ABC. This ABC patient population should be further studied and not be pre-emptively excluded from clinical trials of targeted therapy for BRCA1/2-driven cancers., Competing Interests: Declaration of competing interest J.E.A.M. reports receiving travel compensation from AstraZeneca, Roche; and research grants from AstraZeneca. J.B. has participated as invited speaker for AstraZeneca; has institutional, personal and financial interests in AstraZeneca; has institutional and other financial interests in AstraZeneca-MSD; has been involved in educational programs for AstraZeneca-MSD, declares participation in steering committees for AstraZeneca; reports institutional and financial interests in MEDSIR; and declares being a local principal investigator at MEDSIR. J.A.G.S. declares consultative and advisory services for Seagen, AstraZeneca, Daiichi Sankyo, Novaris, Gilead, Menarini; consultancy/speaker fees from Celgene, Eli Lilly, EISAI, MSD, Exact Sciences, Tecnofarma, Nolver (Adium), Asofarma, Roche; institution and research funding from AstraZeneca; and travel support from Gilead, AstraZeneca, Daiichi Sankyo. I.P. reports receiving honoraria from MSD, Novartis, AstraZeneca, Gildead; and consultancy or advisory role for AstraZeneca. M.F.A. declares speakers' bureaus from Daiichi-AstraZeneca, Lilly, Pfizer, Novartis, Eisai; expert testimony for Lilly; and receiving travel expenses from Roche, Novartis. B.B. reports receiving fees for medical education as consulting or advisory role with MSD, Roche, Pierre Fabre, Novartis, Astra Zeneca, Seagen; and speakers' bureau with Pfizer, Roche, MSD, Palex, Eisai, Daichii, Astra Zeneca, Seagen. M.H.L.C. reports speaker honoraria from Daichii, Novartis & Pierre Fabre; and travel and training grants from Roche, Pfizer, MSD & Novartis. J.P.E. is a full-time employee at MEDSIR. L.C. is a full-time employee at MEDSIR. M.S.C. reports participating in an advisory board for Optimapharm, Ability Pharma, and MD Anderson; and is a full-time employee at MEDSIR. J.M.P.G. declares having a consulting or advisory role for Lilly, Roche, Eisai, Daichii Sankyo, AstraZeneca, Seattle Genetics, Gilead, MSD; travel compensation from Roche; and employment at MEDSIR. J.C. reports serving as a consultant/advisor Roche, AstraZeneca, Seattle Genetics, Daiichi Sankyo, Lilly, Merck Sharp&Dohme, Leuko, Bioasis, Clovis Oncology, Boehringer Ingelheim, Ellipses, Hibercell, BioInvent, Gemoab, Gilead, Menarini, Zymeworks, Reveal Genomics, Scorpion Therapeutics, Expres2ion Biotechnologies, Jazz Pharmaceuticals, Abbvie, BridgeBio; receiving honoraria from Roche, Novartis, Eisai, Pfizer, Lilly, Merck Sharp&Dohme, Daiichi Sankyo, Astrazeneca, Gilead, Steamline Therapeutics; research funding to the Institution from Roche, Ariad pharmaceuticals, AstraZeneca, Baxalta GMBH/Servier Affaires, Bayer healthcare, Eisai, F.Hoffman-La Roche, Guardanth health, Merck Sharp&Dohme, Pfizer, Piqur Therapeutics, Iqvia, Queen Mary University of London; stock of MEDSIR, MAJ3 Capital, Leuko (relative); travel, accommodation, expenses from Roche, Novartis, Eisai, Pfizer, Daiichi Sankyo, Astrazeneca, Gilead, Merck Sharp&Dhome, Steamline Therapeutics; and patents: (1) Pharmaceutical Combinations of A Pi3k Inhibitor And A Microtubule Destabilizing Agent.Javier Cortés Castán, Alejandro Piris Giménez, Violeta Serra Elizalde. WO 2014/199294 A. ISSUED. (2) Her2 as a predictor of response to dual HER2 blockade in the absence of cytotoxic therapy.Aleix Prat, Antonio Llombart, Javier Cortés.US 2019/0338368 A1. LICENSED A.L.C. reports receiving research support from Roche, Agendia, Lilly, Pfizer, Novartis, Merck Sharp & Dohme, Gilead, and Daichii-Sanyo; consulting or advisory role for Lilly, Roche, Pfizer, and Novartis; speakers’ bureaus from Lilly, AstraZeneca, Merck Sharp & Dohme; travel support from Roche, Pfizer, AstraZeneca; and stock or other ownership of MEDSIR and Initia-Research. P.S.R., F.J.S.B., S.M., A.L.M., N.F., P.Z., T.D.R., and M.G. declare that they have not conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: Targeted Agent and Profiling Utilization Registry is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. Results of a cohort of patients with biliary tract cancer (BTC) with ERBB2/3 amplification, overexpression, or mutation treated with pertuzumab plus trastuzumab are reported., Methods: Eligible patients had advanced BTC, measurable disease (RECIST v1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, tumors with ERBB2/3 alterations, and a lack of standard treatment options. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) or stable disease of at least 16+ weeks duration (SD16+) according to RECIST v1.1. Secondary end points included OR, progression-free survival, overall survival, duration of response, duration of stable disease, and safety., Results: Twenty-nine patients were enrolled from February 2017 to January 2022, and all had advanced BTC with an ERBB2/3 alteration. One patient was not evaluable for efficacy. One complete response, eight partial responses, and two SD16+ were observed for DC and OR rates of 40% (90% CI, 27 to 100) and 32% (95% CI, 16 to 52), respectively. The null hypothesis of 15% DC rate was rejected ( P = .0015). Four patients had at least one grade 3 adverse event (AE) or serious AE at least possibly related to treatment: anemia, diarrhea, infusion-related reaction, and fatigue., Conclusion: Pertuzumab plus trastuzumab met prespecified criteria to declare a signal of activity in patients with BTC and ERBB2/3 amplification, overexpression, or mutation.

Objective: Breast cancer is among the highest causes of morbidity and mortality in women. Trastuzumab therapy, which is known to be significantly cardiotoxic, is mainly used to treat patients with resistant breast cancer, including estrogen receptor-positive type. We aimed to show the effects of trastuzumab therapy on endothelial functions of breast cancer patients., Methods: In this study, a total of 26 participants (24 female and 2 male patients, minimum age: 38 years, maximum age: 79 years, and mean age 57.3±12.7 years) were enrolled in the study. For the statistical evaluation of data, we classified the participants of the study as follows: Pretreatment: Before trastuzumab therapy; Treatment Period 1: 1 month after the first dose of trastuzumab; Treatment Period 2: 4 months after the first dose of trastuzumab; Treatment Period 3: 12 months after the first dose of trastuzumab. We conducted repeated-measures analysis of variance (Greenhouse-Geisser) and paired-sample t-tests to statistically compare the groups using flow-mediated dilation measurements., Results: We determined that there are statistically significant differences between flow-mediated hyperemia and ratio values (flow-mediated dilation) of the groups (p<0.009 and p<0.001, respectively)., Conclusion: Our data indicate that trastuzumab therapy could have negative effects on endothelial functions in breast cancer patients.

Purpose: The purpose of this study was to assess the predictive capability of HER2DX assay following (neo)adjuvant trastuzumab-pertuzumab (HP)-based therapy in HER2-positive (HER2+) early breast cancer., Experimental Design: HER2DX was analyzed in baseline pretreatment tumors from the PHERGain trial. Patients with stage I-IIIA HER2+ early breast cancer were randomized to group A [docetaxel, carboplatin, and HP (TCHP)] and group B (HP ± endocrine therapy). PET response was evaluated after two cycles. Group A received TCHP for six cycles regardless of PET response. Group B continued with HP ± endocrine therapy for six cycles (PET responders) or with TCHP for six cycles (PET nonresponders). The primary objective of this retrospective study was to associate the HER2DX pathologic complete response (pCR) score with pCR. The secondary objective was the association of the HER2DX risk score with 3-year invasive disease-free survival (iDFS)., Results: HER2DX was performed on 292 (82.0%) tumors. The overall pCR rate was 38.0%, with pCR rates of 56.4% in group A and 33.8% in group B. In multivariable analysis including treatment and clinicopathologic factors, the HER2DX pCR score (continuous variable) significantly correlated with pCR [OR, 1.29; 95% confidence interval (CI), 1.10-1.54; P < 0.001]. HER2DX-defined pCR-high, -med, and -low groups exhibited pCR rates of 50.4%, 35.8%, and 23.2%, respectively (pCR-high vs. pCR-low OR, 3.27; 95% CI, 1.54-7.09; P < 0.001). In patients with residual disease, the HER2DX high-risk group demonstrated numerically worse 3-year iDFS than the low-risk group (89.8% vs. 100%; HR, 2.70; 95% CI, 0.60-12.18; P = 0.197)., Conclusions: HER2DX predicts pCR in the context of neoadjuvant HP-based therapy, regardless of chemotherapy addition, and might identify patients at higher risk of recurrence among patients with residual disease., (©2024 The Authors; Published by the American Association for Cancer Research.)

Background: No consensus has been reached regarding the optimal chemotherapy for metastatic extramammary Paget's disease (EMPD), a rare cutaneous adenocarcinoma, because of the lack of solid evidence from prospective trials. However, the immunohistochemical profile of EMPD reportedly resembles that of breast cancer, particularly in terms of human epidermal growth factor receptor 2 (HER2) expression, suggesting that HER2 is a promising therapeutic target for advanced HER2-positive EMPD., Methods: In this phase II single-arm trial, 13 Japanese patients received intravenous trastuzumab (loading dose of 8 mg/kg and maintenance dose of 6 mg/kg) and docetaxel (75 mg/m2) every 3 weeks for up to 2 years. The docetaxel dose was reduced or discontinued according to its toxicity. The primary trial endpoints were objective response rate (ORR) after 3 cycles of treatment and safety throughout the study period., Results: All 13 patients completed 3 cycles of combination therapy. The median follow-up was 27.9 months. The ORR was 76.9% (n = 10/13; 90% CI, 50.5-93.4). Frequently observed adverse events were neutropenia (100%), hypoalbuminemia (84.6%), and mucocutaneous infection (84.6%), all of which were well tolerated., Conclusion: The combination of docetaxel and trastuzumab demonstrated a favorable clinical effect and acceptable tolerability, which makes it a good treatment option for HER2-positive metastatic EMPD (ClinicalTrials.gov Identifier: UMIN000021311, jRCTs031180073)., (© The Author(s) 2024. Published by Oxford University Press.)

Dual human epidermal growth factor receptor 2(HER2)blockade with trastuzumab(H)and pertuzumab(P)combined with docetaxel and carboplatin(TCb)is a standard neoadjuvant therapy for HER2-positive breast cancer patients. We conducted this sub-study using data from the investigator-initiated randomized phase 2 JBCRG-20(Neo-peaks)study to evaluate the safety of simultaneous mixed HP infusion in Japanese patients, as there have been no data to date. A total of 204 patients in groups A-C received TCbHP, TCbHP followed by trastuzumab emtansine(T-DM1)+P, and T-DM1+P, respectively. Of the 103 patients in groups A and B who received H and P by sequential infusion in cycle 1, the 17(median age 59; range 29-69 years)who did not experience an infusion reaction(IF)received these agents as a mixed, single-bag infusion from cycle 2 onwards. No cases of IF were observed, thus 71 mixed doses were safely administered. Administration time was reduced to 60 min from cycle 3 onwards. Furthermore, in the group B patients, mixed HP infusion did not affect their subsequent treatment(i. e. 4 cycles of T-DM1+P). Simultaneous administration of H and P enables a reduced administration time, which would benefit both patients and healthcare providers.

Recent studies show increased expression of human epidermal growth factor receptor 2 (HER2) in cervical cancer, but the efficacy of anti-HER2 therapy remains under-researched. Here, we present a case of recurrent HER2-positive serous carcinoma, presumably arising in the cervix, diagnosed by comprehensive genomic profiling, which responded to trastuzumab. The patient underwent a radical hysterectomy with concurrent adjuvant chemoradiotherapy. One year after surgery, the patient experienced recurrence (multiple lymph node metastases). She underwent chemotherapy and subsequent comprehensive genomic profiling, which revealed HER2 positivity. Despite treatment, the lymph node and peritoneal metastases progressed. Therefore, combination chemotherapy with paclitaxel and trastuzumab was initiated. Subsequently, the patient's clinical symptoms improved considerably, and good health was maintained for 8 months. This report highlights the importance of comprehensive genomic profiling and targeted therapies when standard treatments fail., (© 2024 The Author(s). Journal of Obstetrics and Gynaecology Research published by John Wiley & Sons Australia, Ltd on behalf of Japan Society of Obstetrics and Gynecology.)

Breast cancer stem cells (BCSCs) play a key role in therapeutic resistance in breast cancer treatments and disease recurrence. This study aimed to develop a combination therapy loaded with pH-sensitive liposomes to kill both BCSCs and the okbulk cancer cells using trastuzumab-sensitive and resistant human epidermal growth factor receptor 2 positive (HER2 + ) breast cancer cell models. The anti-BCSCs effect and cytotoxicity of all-trans retinoic acid, salinomycin, and bufalin alone or in combination with doxorubicin were compared in HER2 + cell line BT-474 and a validated trastuzumab-resistant cell line, BT-474R. The most potent anti-BCSC agent was selected and loaded into a pH-sensitive liposome system. The effects of the liposomal combination on BCSCs and bulk cancer cells were assessed. Compared with BT-474, the aldehyde dehydrogenase positive BCSC population was elevated in BT-474R (3.9 vs. 23.1%). Bufalin was the most potent agent and suppressed tumorigenesis of BCSCs by ∼50%, and showed strong synergism with doxorubicin in both BT-474 and BT-474R cell lines. The liposomal combination of bufalin and doxorubicin significantly reduced the BCSC population size by 85%, and inhibited both tumorigenesis and self-renewal, although it had little effect on the migration and invasiveness. The cytotoxicity against the bulk cancer cells was also enhanced by the liposomal combination than either formulation alone in both cell lines ( p  < 0.001). The liposomal bufalin and doxorubicin combination therapy may effectively target both BCSCs and bulk cancer cells for a better outcome in trastuzumab-resistant HER2 + breast cancer.

Purpose: HER2-targeted therapies have dramatically improved outcomes of patients with HER2-positive breast cancer (BC), as demonstrated in neoadjuvant trials. This study aims to provide real-world evidence on the use and effectiveness of combined pertuzumab, trastuzumab and chemotherapy (CT) in early-stage HER2-positive BC., Methods: A retrospective, multicentre study was conducted on patients diagnosed with HER2-positive early BC treated with neoadjuvant pertuzumab and trastuzumab plus CT at 13 Spanish sites. The primary endpoint was pathological complete response (pCR)., Results: A total of 310 patients were included. Pertuzumab and trastuzumab were combined with anthracyclines and taxanes, carboplatin and docetaxel, and taxane-based CT in 77.1%, 16.5%, and 6.5% of patients, respectively. Overall, the pCR rate was 62.2%. The pCR was higher amongst patients with hormone receptor-negative tumours and with tumours expressing higher levels of Ki-67 (> 20%). After postoperative adjuvant treatment, 13.9% of patients relapsed. Those patients who did not achieve pCR, with tumours at advanced stages (III), and with node-positive disease were more likely to experience distant relapse. Median overall survival (OS) and distant disease-free survival (D-DFS) were not reached at the study end. The estimated mean OS and D-DFS times were 7.5 (95% CI 7.3-7.7) and 7.3 (95% CI 7.1-7.5) years, respectively (both were significantly longer amongst patients who achieved pCR). Grade 3-4 anti-HER2 related toxicities were reported in six (1.9%) patients., Conclusion: Neoadjuvant pertuzumab and trastuzumab plus CT achieve high pCR rates in real-life patients with HER2-positive early BC, showing an acceptable safety profile. Innovative adjuvant strategies are essential in patients at high risk of distant disease recurrence., (© 2024. The Author(s).)

Competing Interests: We declare no competing interests.

Background: This randomized, parallel-controlled, double-blinded, phase III equivalence study evaluated the equivalence of a proposed pertuzumab biosimilar QL1209 to the pertuzumab (Perjeta®) each with trastuzumab and docetaxel in neoadjuvant treatment of early or locally advanced breast cancer patients with HER2-positive, ER/PR-negative., Methods: Eligible patients were randomly (1:1) assigned to receive 4 cycles of neoadjuvant QL1209 or pertuzumab each with trastuzumab and docetaxel, and adjuvant treatment. The primary endpoint was total pathologic complete response (tpCR), with equivalence margins of 0.76 to 1.32., Results: Among the 585 patients enrolled, 257 and 259 patients were assigned to the QL1209 and pertuzumab groups, respectively. The tpCR rates were comparable in the QL1209 (109/255, 42.75%; 90% CI 37.65 to 47.84) and pertuzumab (117/259, 45.17%; 90% CI 40.09 to 50.26) groups. The tpCR risk ratio was 0.95 (90% CI, 0.80 to 1.11), and the 90% CI fell within the predefined equivalence margin. The most common grade ≥3 treatment-related adverse event was decreased neutrophil count (10. 9% vs. 12.7%) in the QL1209 and pertuzumab groups., Conclusions: QL1209 demonstrated equivalent efficacy and comparable safety profile to the reference pertuzumab in neoadjuvant treatment of HER2-positive, ER/PR-negative, early, or locally advanced breast cancer., Trial Registration: Chinadrugtrials.org CTR20201073; ClinicalTrials.gov NCT04629846., (© 2024. The Author(s).)

Background: In 2008, bevacizumab received accelerated Food and Drug Administration (FDA) approval for use in human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC). Based on the pre-clinical and preliminary clinical activity of the trastuzumab and bevacizumab combination, ECOG-ACRIN E1105 trial was developed to determine if the addition of bevacizumab to a chemotherapy and trastuzumab combination for first-line therapy would improve progression-free survival (PFS) in patients with HER2-positive MBC., Findings: 96 patients were randomized to receive standard first-line chemotherapy and trastuzumab with or without bevacizumab between November 2007 and October 2009, and 93 began protocol therapy. Induction therapy was given for 24 weeks, followed by maintenance trastuzumab with or without bevacizumab. 60% (56/93) began carboplatin and 74% (69/93) completed 6 cycles of induction therapy. Primary endpoint was PFS. Median PFS was 11.1 and 13.8 months for placebo and bevacizumab arms, respectively (hazard ratio [HR] 95%, Confidence Interval [Cl] for bevacizumab vs. placebo: 0.73 [0.43-1.23], p = 0.24), and at a median follow-up of 70.7 months, median survival was 49.1 and 63 months (HR [95% Cl] for OS: 1.09 [0.61-1.97], p = 0.75). The most common toxicities across both arms were neutropenia and hypertension, with left ventricular systolic dysfunction, fatigue, and sensory neuropathy reported more frequently with bevacizumab., Conclusions: In this trial, the addition of bevacizumab did not improve outcomes in patients with metastatic HER2-positive breast cancer. Although the trial was underpowered due to smaller than anticipated sample size, these findings corroborated other clinical trials during this time., Clinical Trial Information: NCT00520975., (© 2024. The Author(s).)

The global phase 3 DESTINY-Breast03 study (ClinicalTrials.gov; NCT03529110) showed statistically significant and clinically meaningful improvements in progression-free survival (PFS) and overall survival (OS) with trastuzumab deruxtecan (T-DXd) over trastuzumab emtansine (T-DM1) in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) previously treated with trastuzumab and a taxane. Here, we report a subgroup analysis of Asian patients enrolled in DESTINY-Breast03. In total, 309 patients (149 in the T-DXd arm and 160 in the T-DM1 arm) from Asian countries and regions were randomized. At data cutoff (July 25, 2022), the median duration of follow-up in the Asian subpopulation was 29.0 months with T-DXd and 26.0 months with T-DM1. The PFS (determined by blinded independent central review) hazard ratio was 0.30 (95% confidence interval 0.22-0.41) favoring T-DXd over T-DM1 (median PFS 25.1 vs. 5.4 months). Median OS was not reached in the T-DXd arm and was 37.7 months in the T-DM1 arm. The median treatment duration was 15.4 months with T-DXd and 5.5 months with T-DM1. The incidence of grade ≥3 drug-related treatment-emergent adverse events was similar between both treatment arms (49.0% vs. 46.5%) and was consistent with the overall DESTINY-Breast03 population. Adjudicated drug-related interstitial lung disease or pneumonitis occurred in 12.9% of patients treated with T-DXd and 2.5% treated with T-DM1, with a higher incidence in Japanese patients; none of these were grade ≥4 events. These efficacy and safety data reinforce the favorable benefit-risk profile of T-DXd in HER2-positive mBC, including in the Asian subgroup., (© 2024 The Author(s). Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Background: Trastuzumab deruxtecan has shown encouraging activity in patients with treatment-refractory HER2-positive, RAS wild-type and BRAF wild-type metastatic colorectal cancer. Dose optimisation and further antitumour assessments in patients with RAS mutations and those with previous anti-HER2 therapy are warranted. We aimed to evaluate two doses of trastuzumab deruxtecan (5·4 mg/kg and 6·4 mg/kg) to establish the recommended dose in patients with pretreated HER2-positive, RAS wild-type or mutant metastatic colorectal cancer., Methods: DESTINY-CRC02 was a multicentre, randomised, two-stage, two-arm, phase 2 study done in 53 research hospitals and medical centres in Australia, Belgium, France, Italy, Japan, South Korea, Spain, Taiwan, the UK, and the USA. Eligible patients were aged 18 years and older or 20 years and older (depending on region) with pretreated pathologically documented, unresectable, recurrent, or metastatic HER2-positive, and RAS wild-type or mutant colorectal cancer. Patients were required to have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 and have received previous chemotherapy, and anti-EGFR, anti-VEGF, or anti-PD-L1 therapy, if clinically indicated. In stage 1, patients were randomly assigned (1:1), via a secure interactive response technology system, to receive 5·4 mg/kg or 6·4 mg/kg trastuzumab deruxtecan administered intravenously every 21 days. Stratification factors were ECOG performance status, HER2 status, and RAS status. In stage 2, patients were assigned into the 5·4 mg/kg treatment group only. The primary endpoint was confirmed objective response rate by blinded independent central review, assessed in all patients for whom treatment was assigned (full analysis set). Safety was assessed in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT04744831, and is ongoing (not recruiting)., Findings: Between March 5, 2021, and March 29, 2022, 135 patients were centrally screened, 122 of whom were enrolled. In stage 1, 40 patients each were randomly assigned to receive trastuzumab deruxtecan 5·4 mg/kg and 6·4 mg/kg. In stage 2, an additional 42 patients were enrolled in the 5·4 mg/kg group. 64 (52%) participants were male and 58 (48%) were female. The median duration of follow-up was 8·9 months (IQR 6·7-10·5) in the 5·4 mg/kg group and 10·3 months (5·9-12·7) in the 6·4 mg/kg group. The confirmed objective response rate by blinded independent central review was 37·8% (31/82 [95% CI 27·3-49·2]) in the 5·4 mg/kg group and 27·5% (11/40 [14·6-43·9]) in the 6·4 mg/kg group. 34 (41%) of 83 patients in the 5·4 mg/kg group and 19 (49%) of 39 in the 6·4 mg/kg group had grade 3 or worse drug-related treatment-emergent adverse events. The most common grade 3 or worse drug-related treatment-emergent adverse events were neutrophil count decreased (13 [16%] of 83 patients), anaemia (six [7%]), nausea (six [7%]), and white blood cell count decreased (five [6%]) in the 5·4 mg/kg group; and were neutrophil count decreased (10 [26%] of 39 patients), anaemia (eight [21%]), platelet count decreased (four [10%]), and white blood cell count decreased (four [10%]) in the 6·4 mg/kg group. Drug-related serious adverse events occurred in 11 (13%) of 83 patients in the 5·4 mg/kg group and six (15%) of 39 patients in the 6·4 mg/kg group; the most common in the 5·4 mg/kg group was nausea (three [4%] patients) and the most common in the 6·4 mg/kg group were fatigue (two [5%] patients), neutropenia (two [5%]), and thrombocytopenia (two [5%]). A drug-related treatment-emergent adverse event related to death occurred in one (1%) patient in the 5·4 mg/kg group (due to hepatic failure). Adjudicated drug-related interstitial lung disease or pneumonitis events were observed in seven (8%) patients in the 5·4 mg/kg group (all grade 1 or 2) and in five (13%) patients in the 6·4 mg/kg group (four grade 1 or 2; one grade 5)., Interpretation: The promising antitumour activity and favourable safety profile support trastuzumab deruxtecan 5·4 mg/kg as the optimal single-agent dose for patients with pretreated HER2-positive metastatic colorectal cancer, including those with RAS mutations, previous anti-HER2 therapy, or both., Funding: Daiichi Sankyo and AstraZeneca., Competing Interests: Declaration of interests KR has received research grants from Bayer, UCB BioSciences, Hibercell, Eisai, Merck, Janssen Pharmaceuticals, AbbVie, Daiichi Sankyo, Guardant Health, Innovent Biologics, and Xencor; has received payment or honoraria from Bayer, Daiichi Sankyo, and Seagen; and has participated on a data safety monitoring board or advisory board for Bayer, Eisai/Merck, SAGA Diagnostics, Daiichi Sankyo, Seagen, Pfizer, and AstraZeneca. SS has participated on a data safety monitoring board or advisory board for Agenus, AstraZeneca, Bayer, Bristol Myers Squibb, CheckmAb, Daiichi Sankyo, GlaxoSmithKline, MSD, Merck, Novartis, Pierre Fabre, Seagen, and T-One Therapeutics. AT has received research grants from Daiichi Sankyo, Ono Pharmaceutical, Bristol Myers Squibb, Pfizer, Merck Sharp & Dome, Isofol Medical, Incyte Corporation, and Hutchison Medipharma; and has received payment or honoraria from Eli Lilly, Taiho Pharmaceutical, Ono Pharmaceutical, Chugai Pharma, Merck Serono, and Takeda. TKat has received payment or honoraria from Chugai Pharmaceutical, Ono Pharmaceutical, Takeda Pharmaceutical, and Eli Lilly. FP has received payment or honoraria from Amgen, Merck-Serono, MSD, BMS, Astellas, Johnson & Johnson, Takeda, Bayer, Servier, Pierre Fabre, Ipsen, GSK, and Rottapharm. YK has received royalties or licenses from Ono Pharmaceutical, Chugai Pharmaceutical, Taiho Pharmaceutical, Shionogi, Nippon Zoki Pharmaceuticals, Asahi Kasei Pharma Corporation, Nippon, Kayaku, Daiichi Sankyo, IQVIA Services Japan, MSD, Astellas Pharma, Incyte Corporation, Eisai, National Cancer Center Japan, Syneos Health Clinical, ShiftZero, Parexel International, Japan Clinical Cancer Research Organization, EPS Holdings, Sysmex Corporation, Public Health Research Foundation, Aichi Cancer Center, and Kyushu Study group of Clinical Cancer; and has received payment or honoraria from Ono Pharmaceutical, TAIHO Pharmaceutical, Astellas Pharma, EA Pharma, Daiichi Sankyo, Nippon, Kayaku, Pfizer, Nippon Zoki Pharmaceuticals, Sanofi, NIPRO, MOROO, Alfresa Pharma Corporation, Boehringer Ingelheim, Hakodate National Hospital, Asahi Kasei Pharma Corporation, Chugai Pharmaceutical, MSD, Zeria Pharmaceutical, Bayer Yakuhin, Eli Lilly, Yakult Honsha, Sumitomo Dainippon Pharma, Incyte Corporation, Merck Biopharma, The Japanese Gastroenterological Association, Sapporo Minami Tokushukai Hospital, and Pancan Japan. HK has received consulting or advisory fees from Astellas Pharma, Daiichi-Sankyo, and AbbVie; honoraria from Bristol Myers Squibb, Bayer Yakuhin, Ono Pharmaceutical, Eli Lilly Japan, MSD, Chugai Pharmaceutical, Daiichi-Sankyo, Merck Biopharma, Teijin Pharma, Takeda Pharmaceutical, Yakult Pharmaceutical Industry, Taiho Pharmaceutical, Amgen, Otsuka Pharmaceutical, GlaxoSmithKline, and Nippon Kayaku; and research funding from Bristol Myers Squibb, Kobayashi Pharmaceutical, and Eisai. MP has received research grants from Amgen, Bayer, Bristol Myers Squibb, Ipsen, Novartis, and Roche; has received payment or honoraria from Amgen, Bayer, Bristol Myers Squibb, Merck, MSD, Roche, Sanofi, Servier, and Sirtex; has received consulting fees from Amgen, Bayer, Ipsen, Merck, MSD, Qurin, Remedus, Sanofi, Sirtex, and Terumo; and has participated on a data safety monitoring board or advisory board for Basilea. TA has received payment or honoraria from AstraZeneca, Bristol Myers Squibb, Gritstone Oncology, GlaxoSmithKline, Merck, Pierre Fabre, Seagen, and Servier Transgéne; has received support for attending meetings or travel from Bristol Myers Squibb and Merck; has received consulting fees from Aptitude Health, Astellas, Bristol Myers Squibb, Gritstone Oncology, GamaMabs Pharma, GlaxoSmithKline, Kaleido Oncology, Merck, Pierre Fabre, Seagen, Servier, and Transgène; and is president of the ARCAD Foundation. SL has received research grants from Amgen, Astellas, AstraZeneca, Bayer, Bristol Myers Squibb, Daiichi Sankyo, Hutchinson, Incyte, Merck Serono, Mirati, MSD, Pfizer, Roche, and Servier; has received payment or honoraria from Amgen, Bristol Myers Squibb, Incyte, GlaxoSmithKline, Eli Lilly, Merck Serono, MSD, Pierre Fabre, Roche, and Servier; and has received consulting fees from Amgen, Astellas, AstraZeneca, Bayer, Bristol Myers Squibb, Daiichi Sankyo, GSK, Incyte, Eli Lilly, Merck Serono, MSD, Pierre Fabre, Roche, Takeda, and Servier. KY has received research grants from Taiho Pharm; and has received honoraria from Daiichi Sankyo, Chugai Pharmaceutical, Bristol Myers Squibb, Eli Lilly Japan, Taiho Pharmaceutical, Ono Pharmaceutical, Takeda Pharmaceutical, and Merck. JT has received honoraria from Servier and Pierre Fabre; has received consulting fees from Haystack Oncology; has participated on a data safety monitoring board or advisory board for Gilead, MSD, Bristol Myers Squibb, Pierre Fabre, Novartis, and Daiichi Sankyo; and has participated with leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid for Australasian Gastro-Intestinal Trials Group and European Society for Medical Oncology. CGC has received honoraria from Amgen, Merck, Servier, Pierre Fabre, and Incyte; has received support for attending meetings or travel from Merck, Servier, and Pierre Fabre; and is the Secretary of the Spanish Group for Treatment of Gastrointestinal Tumours (TTD). JHS has received research grants from AbbVie, Amgen, AStar D3, Bayer, Curegenix, Daiichi Sankyo, Eli Lilly, Erasca, Gossamer Bio, Leap Therapeutics, Nektar, Roche/Genentech, Sanofi, Seagen, and Silverback Therapeutics; has received payment or honoraria from Seagen, Bayer, and Natera; has received consulting fees from AbbVie, Amgen, AstraZeneca, Bayer, Beigene, Daiichi Sankyo, Eli Lilly, GlaxoSmithKline, Natera, Pfizer, Roche/Genentech, Seagen, Silverback Therapeutics, Takeda, and Viatris; has participated on a data safety monitoring board or advisory board for AbbVie, Pionyr Immunotherapeutics, and Beigene; and has received support for attending meetings or travel from Seagen. YC has received consulting fees from IMBdx, Ono Pharmaceutical, Boryung Pharmaceutical, Interpark Bioconvergence, and GC Genome Corporation; and has received honoraria from Roche and MSD Korea. DB is an employee of Daiichi Sankyo. QY has received employee benefits (stocks or other financial or non-financial interests) from Daiichi Sankyo. TKam has received employee benefits (financial or non-financial interests) from Daiichi Sankyo. KK is an employee of Daiichi Sankyo. AB has received employee benefits (stocks or other financial or non-financial interests) from Daiichi Sankyo; and has received support for attending meetings or travel from Daiichi Sankyo. MK is an employee of Daiichi Sankyo. JDA has received employee benefits (stocks or other financial or non-financial interests) from Daiichi Sankyo. TY has received research grants from Amgen, Chugai Pharmaceutical, Daiichi Sankyo, Eisai, FALCO Biosystems, Genomedia, Molecular Health, MSD, Nippon Boehringer Ingelheim, Ono Pharmaceutical, Pfizer Japan, Roche Diagnostics, Sanofi, Sysmex, and Taiho Pharmaceutical; has received honoraria from Chugai Pharmaceutical, Takeda Pharmaceutical, Merck Biopharma, Bayer Yakuhin, Ono Pharmaceutical, and MSD; and has received consulting fees from Sumitomo Corporation. MVdE, H-CH, and T-YK declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Background: Current guidelines recommend that patients with HER2-low metastatic breast cancer (MBC) receive sequentially two antibody-drug conjugates (ADCs): Sacituzumab Govitecan (SG) and Trastuzumab Deruxtecan (T-DXd), despite a similar payload. However, the effectiveness of one after another is unknown., Methods: ADC-Low is a multicentre, retrospective study evaluating the efficacy of SG and T-DXd, one after another, with or without intermediary lines of chemotherapy, in patients with HER2-low MBC., Results: One hundred and seventy-nine patients were included: the majority with HR-negative tumours received SG first (ADC1) (n = 100/108) while most with HR-positive tumours received T-DXd first (n = 56/71). Median progression-free survival 2 was short: 2.7 months (95% CI: 2.4-3.3) in the whole population, respectively, 3.1 (95% CI: 2.6-3.6) and 2.2 months (95% CI: 1.9-2.7) for patients receiving T-DXd or SG second (ADC2). Intermediary lines of chemotherapy between ADC1 and ADC2 had no impact. Primary resistance to ADC2 occurred in 54.4% of patients. Certain patients showed initial response to ADC2., Conclusions: Clinical benefit of sequentially administered SG and T-DXd is limited for most patients. Nevertheless, a subset of patients might benefit-on the short term-from a second ADC. Additional studies are needed to identify patients who could benefit from two ADCs with similar payloads., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Currently, therapy for early-stage human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC) is based on the combination of trastuzumab and pertuzumab plus chemotherapy in a neoadjuvant regimen. The INMUNOHER study aimed to detect immunological markers in peripheral blood and their association with treatment response. Sixty-two HER2+ BC patients were recruited. Pre-treatment samples were obtained before the start of treatment, while post-treatment samples were obtained after completing therapy and before surgery and were analyzed by flow cytometry. The pathologic complete response (pCR) rate achieved was 82.3%. The expression of the NKp30, PD-1, and TIM-3 receptors was reduced in the Natural Killer (NK)-CD56dim subset of patients who did not achieve pCR. Following therapy, many changes were found in leukocytes, including alterations in T cell lymphocyte proportions. Also, the percentage of NK cells decreased, and several phenotypic changes were observed in this population. After treatment, IFN-γ production by NK cells against HER2+-cells with or without trastuzumab was significantly reduced. HER2-targeted therapy plus chemotherapy demonstrated high efficacy in most patients, reducing the statistical power for finding immunological markers. However, NK subset phenotypes correlated better with response groups, and numerous changes in the percentage of leukocytes and T and NK cells, as well as changes in the functionality of NK cells, were observed in most patients after treatment, encouraging further research into these immune populations.

Background: TCbHP (taxane + carboplatin + trastuzumab + pertuzumab) is the preferred neoadjuvant therapy regimen for human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, no consensus exists regarding whether specific populations may be exempt from carboplatin, allowing for de-escalation to the THP (taxane + trastuzumab + pertuzumab) regimen. Additionally, the optimal number of cycles for neoadjuvant THP remains unclear. We compared the efficacy and safety of neoadjuvant TCbHP and THP regimens, providing clinicians with a nuanced perspective to guide their treatment regimen selection., Methods: This multicenter real-world study included patients with HER2-positive breast cancer undergoing neoadjuvant TCbHP or THP between March 2019 and February 2023. Efficacy was assessed through the pathological complete response (pCR) rate, while safety was evaluated through monitoring adverse events., Results: Among 220 patients, 103 received 6 cycles of TCbHP (TCbHP×6), 83 received 6 cycles of THP (THP×6), and 34 received 4 cycles of THP (THP×4). The TCbHP×6 cohort exhibited a 66% pCR rate compared with 53% in the THP×6 cohort (P = 0.072). Subgroup analysis revealed that in patients aged ≤ 50 years, those with hormone receptor (HR)-negative status, and those with clinical stage T2, the pCR rate of the TCbHP×6 regimen was significantly higher than the THP×6 regimen (P < 0.05). The TCbHP×6 cohort reported higher frequencies of any-grade adverse events (99% versus 86.7%) and grade 3-4 events (49.5% versus 12%) than the THP×6 cohort. Propensity score matching identified 27 patient pairs between the THP×6 and THP×4 cohorts, indicating a significantly higher pCR rate for the THP×6 regimen than the THP×4 regimen (63% versus 29.6%, P = 0.029)., Conclusions: The TCbHP×6 regimen is favored for individuals aged ≤ 50 years and those aged > 50, ≤60 years with HR-negative status or clinical stage T2-4. For patients in compromised general condition or lacking the specified indications, the THP×6 regimen emerges as a lower-toxicity alternative with satisfactory efficacy. To ensure treatment efficacy, a minimum of 6 cycles of neoadjuvant THP is required., (© 2024. The Author(s).)

Preclinical studies suggest that simultaneous HER2/VEGF blockade may have cooperative effects in gastroesophageal adenocarcinomas. In a single-arm investigator initiated clinical trial for patients with untreated advanced HER2+ gastroesophageal adenocarcinoma, bevacizumab was added to standard of care capecitabine, oxaliplatin, and trastuzumab in 36 patients (NCT01191697). Primary endpoint was objective response rate and secondary endpoints included safety, duration of response, progression free survival, and overall survival. The study met its primary endpoint with an objective response rate of 81% (95% CI 65-92%). Median progression free and overall survival were 14.0 (95% CI, 11.3-36.4) and 23.2 months (95% CI, 16.6-36.4), respectively. The median duration of response was 14.9 months. The regimen was well tolerated without unexpected or severe toxicities. In post-hoc ctDNA analysis, baseline ctDNA features were prognostic: Higher tumor fraction and alternative MAPK drivers portended worse outcomes. ctDNA at resistance identified oncogenic mutations and these were detectable 2-8 cycles prior to radiographic progression. Capecitabine, oxaliplatin, trastuzumab and bevacizumab shows robust clinical activity in HER2+ gastroesophageal adenocarcinoma. Combination of VEGF inhibitors with chemoimmunotherapy and anti-PD1 regimens is warranted., (© 2024. The Author(s).)

Background: The optimal sequential strategy for antibody-drug conjugates (ADCs) in breast cancer remains uncertain. This study aimed to evaluate the efficacy and potential resistance of second ADC (ADC2) following the first ADC (ADC1) in human epidermal growth factor receptor 2 (HER2)-positive and HER2-low MBC., Methods: This retrospective, multicenter, real-world study enrolled patients with MBC who received at least 2 different types of ADCs in 3 hospitals in China between July 1, 2017 and May 1, 2023. Outcomes included the objective response rate (ORR) for ADC1 and ADC2, progression free survival 2 (PFS2), defined as the time from initiation of ADC2 to progression, and overall survival (OS)., Results: Seventy-nine female patients were included, 64 of whom had HER2-positive disease. The ORR for ADC2 with similar payload of ADC1 was found to be 5.3%. When switching to a different payload, the ORR of ADC2 increased to 22.6%. The PFS2 for ADC2 remained similar regardless of whether the payload was similar or different. Switching to different payload showed a higher ORR in patients with rapid progression and a durable response longer than 6 months (41.2% vs 15.0%). Specifically, significantly longer PFS2 and OS were seen in patients treated with trastuzumab deruxtecan (T-Dxd) compared to those treated with disitamab vedotin (RC48) after progression from trastuzumab emtansine (T-DM1; median PFS2 5.37 months vs 3.30 months, HR = 0.40, 95% CI 0.17-0.93, P = .034; median OS 50.6 months vs 20.2 months, HR = 0.27, 95% CI 0.08-0.91, P = .034). For patients who progressed after T-Dxd, the median PFS2 was 6.05 months for those treated with RC48 versus 0.93 months for those treated with T-DM1 (HR = 0.03, 95% CI 0.002-0.353, P = .0093). Genomic analysis revealed that alternation of retinoblastoma1 was significantly associated with superior PFS., Conclusion: The alternation of payload achieves different responses in different settings. T-Dxd followed by RC48 may be a potentially beneficial strategy in HER2-positive disease. Further research is needed to elucidate the mechanism of cross-resistance., (© The Author(s) 2024. Published by Oxford University Press.)

Introduction: Antibody-drug conjugates (ADCs) represent a revolutionary approach in the systemic treatment for both solid and hematologic tumors. Constituted by an antibody, a cytotoxic payload, and a linker, ADCs aim to selectively deliver cytotoxic agents to tumors while sparing normal tissues. Various ADCs have been tested and approved for multiple solid tumors so far, but if there is one that had a major impact on clinical practice, this is Trastuzumab-deruxtecan (T-DXd). Notably, T-DXd was approved for HER2-positive and HER2-low metastatic breast cancer (MBC), HER2-positive gastric cancer (GC), HER2-mutant non-small cell lung cancer (NSCLC) and HER2 3+ solid tumors. Moreover, it received Breakthrough Therapy Designation for HER2-positive colorectal cancer (CRC)., Areas Covered: We review preclinical and clinical data of T-DXd, focusing on early-phase ongoing trials exploring combination therapies to enhance the activity of T-DXd in HER2-expressing solid tumors., Expert Opinion: The clinical use of T-DXd still raises questions about selection of patients, treatment duration, prioritization over other approved ADCs, and management of resistance. Concerns regarding the toxicity of T-DXd remain, particularly with combinations involving potentially toxic drugs. Advancements in biomarker identification and combination therapies offer promising avenues to enhance efficacy and overcome resistance to T-DXd, ultimately improving outcomes for patients with cancer.

Importance: The standard adjuvant treatment for patients with ERRB2-positive breast cancer is chemotherapy plus 1 year of trastuzumab. Shorter durations of trastuzumab administration improve cardiac safety, but more information is needed about their effect on survival., Objective: To compare survival outcomes after 9-week vs 1-year administration of trastuzumab with the same adjuvant chemotherapy., Design, Setting, and Participants: This post hoc secondary analysis of an open-label, multicenter, noninferiority-design randomized clinical trial included women aged 18 years or older with early ERBB2-positive, axillary node-negative or axillary node-positive breast cancer who were enrolled from January 3, 2008, to December 16, 2014, at 65 centers in 7 European countries. The current exploratory analysis was conducted after achieving the maximum attainable follow-up data when the last patient enrolled had completed the last scheduled visit in December 2022., Intervention: Chemotherapy consisted of 3 cycles of docetaxel administered at 3-week intervals followed by 3 cycles of fluorouracil, epirubicin, and cyclophosphamide at 3-week intervals. Trastuzumab was administered in both groups for 9 weeks concomitantly with docetaxel. In the 9-week group, no further trastuzumab was administered after chemotherapy, whereas in the 1-year group, trastuzumab was continued after chemotherapy to complete 1 year of administration., Main Outcomes and Measures: The primary objective was disease-free survival (DFS). Distant DFS and OS were secondary objectives. Survival between groups was compared using the Kaplan-Meier method and log-rank test or univariable Cox proportional hazards regression., Results: Among the 2174 women analyzed, median age was 56 years (IQR, 48-64 years). The median follow-up time was 8.1 years (IQR, 8.0-8.9 years); 357 DFS events and 176 deaths occurred. Trastuzumab for 9 weeks was associated with shorter DFS compared with trastuzumab for 1 year (hazard ratio [HR], 1.36; 90% CI, 1.14-1.62); 10-year DFS was 80.3% in the 1-year group vs 78.6% in the 9-week group. The 5-year and 10-year OS rates were comparable between the 9-week and 1-year groups (95.0% vs 95.9% and 89.1% vs 88.2%, respectively; HR for all time points, 1.20; 90% CI, 0.94-1.54). In multivariable analyses, 9-week treatment was associated with shorter DFS compared with 1-year treatment (HR for recurrence or death, 1.36; 95% CI, 1.10-1.68; P = .005), but there was no between-group difference in OS (HR, 1.22; 95% CI, 0.90-1.64; P = .20). Only 4 patients (0.2%) died of a cardiac cause., Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, 1-year vs 9-week adjuvant trastuzumab was associated with improved DFS among patients with ERRB2-positive breast cancer receiving chemotherapy, but there was no significant difference in OS between the groups., Trial Registration: ClinicalTrials.gov Identifier: NCT00593697.

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.

Purpose: The randomized phase 2 Neo-peaks study examined usefulness of neoadjuvant trastuzumab emtansine + pertuzumab (T-DM1 + P) following docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) as compared with the standard TCbHP regimen. We previously reported that pCR rate after neoadjuvant therapy tended to be higher with TCbHP followed by T-DM1 + P. We conducted an exploratory analysis of prognosis 5 years after surgery., Methods: Neoadjuvant treatment with TCbHP (6 cycles; group A), TCbHP (4 cycles) followed by T-DM1 + P (4 cycles; group B), and T-DM1 + P (4 cycles; group C, + 2 cycles in responders) were compared. Group C non-responders after 4 cycles were switched to an anthracycline-based regimen. We evaluated 5-year disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS)., Results: Data from 203 patients (50, 52, and 101 in groups A-C, respectively) were analyzed. No significant intergroup differences were found for DFS, DDFS, or OS. The 5-year DFS rates (95% CI) were 91.8% (79.6-96.8%), 92.3% (80.8-97.0%), and 88.0% (79.9-93.0%) in groups A-C, respectively. TCbHP followed by T-DM1 + P and T-DM1 + P with response-guided addition of anthracycline therapy resulted in similar long-term prognosis to that of TCbHP., Conclusions: In patients who achieved pCR after neoadjuvant therapy with T-DM1 + P, omission of adjuvant anthracycline may be considered, whereas treatment should be adjusted for non-pCR patients with residual disease. T-DM1 + P with response-guided treatment adjustment may be useful for minimizing toxicity., Trial Registration Number and Date of Registration: UMIN-CTR, UMIN000014649, prospectively registered July 25, 2014. Some of the study results were presented as a Mini Oral session at the ESMO Breast Cancer 2023 (Berlin, Germany, 11-13 May 2023)., (© 2024. The Author(s).)

Background: Inetetamab is the first domestically developed innovative anti-HER2 monoclonal antibody in China, proven effective and safe in HER2-positive advanced breast cancer. However, its efficacy and safety in neoadjuvant treatment of HER2-positive locally advanced breast cancer (LABC) remain to be validated., Methods: This prospective cohort study aimed to evaluate the efficacy and safety of inetetamab combined with pertuzumab, taxanes, and carboplatin (TCbIP) in neoadjuvant therapy for HER2-positive LABC, comparing it to data from patients treated with the TCbHP regimen (trastuzumab combined with pertuzumab, taxanes, and carboplatin) using propensity score matching (PSM). The primary endpoint was total pathological complete response (tpCR). Adverse events (AEs), objective response rate (ORR), and near-pCR were key secondary endpoints., Results: Forty-four patients with clinical stage IIA-IIIC HER2-positive LABC were prospectively enrolled and treated with the TCbIP regimen. The tpCR rate among 28 patients who completed surgery was 60.7%, comparable to and slightly higher than the TCbHP group in PSM (60.7% vs. 53.6%, P = 0.510). The ORR was 96.4%, and the DCR reached 100.0%. The most common ≥ grade 3 AE was neutropenia (21.4% vs. 11.9%, P = 0.350). No significant reduction in left ventricular ejection fraction was observed, and no patient withdrew from treatment due to AEs., Conclusion: Neoadjuvant therapy with TCbIP showed good efficacy and safety in patients with HER2-positive LABC and might be another promising option for neoadjuvant treatment., Trial Registration: NCT05749016 (registration date: Nov 01, 2021)., (© 2024. The Author(s).)

Supramolecular delivery systems with the prolonged circulation, the potential for diverse functionalization, and few toxin-related limitations have been extensively studied. For the present study, we constructed a linear polyglycerol-shelled polymersome attached with the anti-HER-2-antibody trastuzumab. We then covalently loaded the anticancer drug DM1 in the polymersome via dynamic disulfide bonding. The resulted trastuzumab-polymersome-DM1 (Tra-PS-DM1) exhibits a mean size of 95.3 nm and remarkable drug loading efficiency % of 99.3%. In addition to its superior stability, we observed the rapid release of DM1 in a controlled manner under reductive conditions. Compared to the native polymersomes, Tra-PS-DM1 has shown greatly improved cellular uptake and significantly reduced IC 50 up to 17-fold among HER-2-positive cancer cells. Moreover, Tra-PS-DM1 demonstrated superb growth inhibition of HER-2-positive tumoroids; specifically, BT474 tumoroids shrunk up to 62% after 12 h treatment. With exceptional stability and targetability, the PG-shelled Tra-PS-DM1 appears as an attractive approach for HER-2-positive tumor treatment.

Anti-cancer therapy with anthracyclines and trastuzumab has raised concerns regarding cancer therapy-related cardiac dysfunction (CTRCD) in breast cancer (BC) patients. This study aimed to assess left ventricular (LV) ultrasound parameters in BC postmenopausal women during a 2-year follow-up period after starting anti-cancer therapy., Methods: We studied 74 women with early-stage BC with, a mean age of 62.3 (SD-8.6), who underwent adjuvant doxorubicin or doxorubicin + trastuzumab therapy. Parameters such as LV ejection fraction (LVEF), global longitudinal strain (LVGLS), and mitral annulus systolic velocity(S') were evaluated. Serial evaluations were conducted at baseline(T0) and the first (T1), second (T2), third (T3), sixth (T4), ninth (T5), twelfth (T6), and twenty-fourth month (T7) following the initiation of the chemotherapy. Cardioprotective therapy (CPT) was administered to high-risk patients and those with worsening LV systolic parameters. A multiple regression model was employed to assess the combined effects of various factors and co-factors on the outcome variables. Cardiotoxicity was evaluated using the survival analysis tools (Kaplan-Meier curves and Cox proportional model)., Results: A total of 27 (36.5%) patients developed CTRCD, although no patients were presented with symptomatic heart failure. LVGLS started to decline one month after the first anthracycline dose (T1) in 13.5% of the cohort and 34.5% of patients with CTRCD (p<0.000). From the third month, 10.8% of the patients showed a decrease in EF%, including 27.6% of patients with CTRCD in (P<0.000). Throughout, the study, S' remained within the normal range in patients without CTRCD, only patients with CTRCD showed a decline in S'., Conclusions: This prospective study revealed that:1) The dynamic assessment of GLS should be prioritized for the early detection of systolic dysfunction .2) S' possesses a high diagnostic value for identifying cardiotoxicity. 3) Implementing the optimal medical cardioprotective strategies and closely monitoring LV systolic function can prevent serious cardiac complications in patients undergoing highly cardiotoxic anti-cancer treatment.

Purpose: This study aims to evaluate the efficacy and safety of trastuzumab biosimilar (HLX02) in combination with pertuzumab and chemotherapy in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) after progression of trastuzumab., Materials and Methods: In this prospective, single-arm, phase II study, patients with HER2-positive MBC after progression of trastuzumab received pertuzuamb, HLX02, and chemotherapy in Beijing Cancer Hospital from March 2020 to December 2022. The primary endpoint was progression-free survival (PFS), and secondary endpoints included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety. The study was registered with ClinicalTrials.gov (NCT05188495)., Results: A total of 45 patients were included in this study. Twelve patients (26.7%) were treated in second-line and 33 patients (73.3%) were in third-line and later setting. Eighty percent and 15.5% patients had previously received pyrotinib/lapatinib and T-DM1, respectively. With a median follow-up of 24.4 months (range, 1.2 to 43.9 months), the median PFS was 7.6 months (95% confidence interval, 4.3 to 10.9), OS was not reached, the ORR was 31.1%, and DCR was 91.1%. The treatment was well tolerated., Conclusion: The combination of trastuzumab biosimilar HLX02, pertuzumab, and chemotherapy exhibited promising efficacy and a favorable safety profile as second- and beyond-line treatment in HER2-positive MBC.

Background: Due to cardiotoxicity concerns, the concurrent use of epirubicin and trastuzumab has not been fully studied. This study aimed to examine the cardiotoxicity and pathological complete response (pCR) rate associated with the concurrent regimens in patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer (EBC)., Methods: We conducted a systematic search for relevant literature in the NCBI/PubMed, the Cochrane database, and international conference abstracts for phase II or III randomized controlled trials between January 1, 2000, and February 28, 2021, focusing on the concurrent regimens in patients with HER2-positive EBC. To compare the risk of cardiotoxicity and the odds of the pCR rate, we performed linear meta-regression analyses to investigate the effects of multiple covariates., Results: We analyzed 7 neoadjuvant trials involving the concurrent use of epirubicin and trastuzumab with 1797 patients. The median cumulative dose of epirubicin used was 300 mg/m 2 , with a total of 96 reported adverse cardiac events. The concurrent regimens did not result in a significant increase in cardiotoxicity compared to nonconcurrent regimens (risk ratio [RR] = 1.18, 95% confidence interval [CI] = 0.68-2.05). Compared with nonconcurrent or non-anthracycline-containing regimens, concurrent regimens were associated with a significant increase in the pCR rate (odds ratio = 1.48, 95% CI = 1.04-2.12). The linear fixed-effects meta-regression analysis indicated that in trials including more patients with hormone receptor-positive EBC, the RR of cardiotoxicity significantly increased with concurrent regimens, and the pCR rate became less significant., Conclusions: The combination of trastuzumab and a low dose of epirubicin positively impacted the pCR rate without a significant increase in cardiotoxicity. We recommend exploring concurrent regimens for HR-negative, HER2-positive tumors to enhance pCR rates, with caution advised for HR-positive tumors due to potential cardiotoxicity., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Liposomes carrying chemotherapeutic drugs can accumulate passively in solid tumors at high levels. However, additional targeting of the liposomes towards e.g. receptors expressed on cancer cells may improve their interaction and therapeutic properties. In this study, we designed a liposomal delivery system, which utilizes the intrinsic characteristics of HER2-positive tumors to ensure efficient delivery of oxaliplatin to the cancer cells. On the liposome surface, trastuzumab, an antibody specific to the HER2 receptor, was shown to facilitate internalization by the cancer cells. A polyethylene glycol (PEG) layer on the liposome surface provides protection from mononuclear phagocyte system uptake. To optimize the interaction between liposomes and cancer cells, a protease-sensitive cleavable peptide linker was inserted at the base of each PEG. The PEG layer is then cleaved off by intra- and extracellular matrix metalloproteinases (MMPs) upon accumulation in the tumor. Our data demonstrate that the removal of PEG significantly destabilizes the liposomes and leads to substantial oxaliplatin release. The proposed beneficial effect of combining antibody-mediated internalization with MMP sensitivity was confirmed in a series of in vivo studies using ovarian cancer xenograft models. The results demonstrated that HER2-targeted MMP-sensitive liposomes have superior anticancer activity compared to non-targeted and non-cleavable liposomes., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023. Published by Elsevier B.V.)

Background and Objective: Trastuzumab targets human epidermal growth factor receptor 2 (HER2) receptors and is indicated for treating HER2-positive metastatic breast cancer. BP02, a recombinant IgG1 kappa humanized monoclonal antibody, is being developed as a trastuzumab biosimilar. The objective of this study was to evaluate the equivalence of BP02 with reference trastuzumab (RT: Herceptin ® -EU) in patients with HER2-positive metastatic breast cancer., Methods: This double-blinded, 1:1 randomized, parallel-group, active-controlled, phase III equivalence trial recruited women aged 18-75 years with histologically/cytologically confirmed HER2- positive, locally recurrent or metastatic breast cancer with systemic metastasis, from 59 sites in India. Patients were randomly allocated 1:1 stratified by estrogen receptor/progesterone receptor status to receive BP02/RT (8-mg/kg loading dose on day 1-cycle 1, 6 mg/kg on day 1-cycles 2-8, of each 3-week cycle) combined with docetaxel (75 mg/m 2 on day 1-cycles 1-8) [induction phase]. Participants with complete or partial response, or stable disease at the end of the induction phase continued the study drug until disease progression/treatment discontinuation [maintenance phase]. The primary efficacy endpoint was the objective response rate per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1., Results: Between 23 September, 2020 and 16 September, 2022, 690 patients were recruited (n = 345 each to BP02/RT). At the end of the induction phase (intent-to-treat population), a similar proportion of patients achieved an objective response rate with BP02 (n = 231 [67.0%], 95% confidence interval [CI] 62.0, 71.9) and RT (n = 238 [69.0%], 95% CI 64.1, 73.9). The 95% CI of risk difference (-2.03, 95% CI -9.15, 5.09) and 90% CI of risk ratio (0.97, 90% CI 0.89, 1.06) were within equivalence margins of ± 13% and (0.80, 1.25), respectively. Treatment-emergent adverse events leading to treatment withdrawal were reported in 2.9% and 3.2% patients with BP02 and RT, respectively., Conclusions: BP02 showed an equivalent efficacy and similar safety profile to RT at the end of 24 weeks., Clinical Trial Registration: CTRI Number: CTRI/2020/04/024456., (© 2024. The Author(s).)

Background: The addition of pertuzumab (P) to trastuzumab (H) and standard chemotherapy (CT) as neoadjuvant treatment (NaT) for patients with HER2 + breast cancer (BC), has shown to increase the pathological complete response (pCR) rate, without main safety concerns. The aim of NeoPowER trial is to evaluate safety and efficacy of P + H + CT in a real-world population., Methods: We retrospectively reviewed the medical records of stage II-III, HER2 + BC patients treated with NaT: who received P + H + CT (neopower group) in 5 Emilia Romagna institutions were compared with an historical group who received H + CT (control group). The primary endpoint was the safety, secondary endpoints were pCR rate, DRFS and OS and their correlation to NaT and other potential variables., Results: 260 patients were included, 48% received P + H + CT, of whom 44% was given anthraciclynes as part of CT, compared to 83% in the control group. The toxicity profile was similar, excluding diarrhea more frequent in the neopower group (20% vs. 9%). Three patients experienced significant reductions in left ventricular ejection fraction (LVEF), all receiving anthracyclines. The pCR rate was 46% (P + H + CT) and 40% (H + CT) (p = 0.39). The addition of P had statistically correlation with pCR only in the patients receiving anthra-free regimens (OR = 3.05,p = 0.047). Preoperative use of anthracyclines (OR = 1.81,p = 0.03) and duration of NaT (OR = 1.18,p = 0.02) were statistically related to pCR. 12/21 distant-relapse events and 14/17 deaths occurred in the control group. Patients who achieve pCR had a significant increase in DRFS (HR = 0.23,p = 0.009)., Conclusions: Adding neoadjuvant P to H and CT is safe. With the exception of diarrhea, rate of adverse events of grade > 2 did not differ between the two groups. P did not increase the cardiotoxicity when added to H + CT, nevertheless in our population all cardiac events occurred in patients who received anthracycline-containing regimens. Not statistically significant, higher pCR rate is achievable in patients receiving neoadjuvant P + H + CT. The study did not show a statistically significant correlation between the addition of P and long-term outcomes., (© 2024. The Author(s).)

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., (© 2024. The Author(s).)

Aim: There has been significant progress made in developing novel targeted therapies in the neoadjuvant setting for non-metastatic HER2-positive breast cancer, which may be used in combination with conventional chemotherapy to optimise pathological responses at surgery. However, these therapies, particularly the chemotherapeutic components, may portend significant and long-lasting toxicity. Hence, de-escalation of treatment intensity has been an area of interest and was evaluated in the phase II NeoSphere study. Herein, we report the real-world pathological and survival outcomes from neoadjuvant taxane and dual HER2 blockade recorded at our centre., Methods: This was a retrospective cohort study of patients receiving neoadjuvant pertuzumab, trastuzumab and taxane chemotherapy for non-metastatic HER2-positive breast cancer at a single centre in Sydney, Australia. We collected data pertaining to baseline demographic characteristics, pathological response rates, post-surgical prescribing patterns and also undertook survival analyses for invasive disease-free survival (iDFS) as well as exploratory analyses for correlations between pre-specified clinicopathologic factors and pathological response at surgery., Results: Our population was largely similar at baseline to the NeoSphere study. 71 patients were included in the final analysis. 61% achieved a pathological complete response (pCR). Three patients received conventional chemotherapy in the adjuvant setting. 92% of included patients were alive and disease-free at 3 years of follow-up. Only 3 events of recurrence or death were recorded at a median follow-up of 32 months. No significant difference in iDFS was noted between patients achieving pCR and those with residual disease at surgery., Conclusion: This study demonstrates that de-escalated adjuvant treatment for HER2-positive early breast cancer achieved favourable pathological and long-term outcomes comparable to large trials, some utilising more intensive chemotherapeutic components., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Displaying antibodies on carrier surfaces facilitates precise targeting and delivery of drugs to diseased cells. Here, we report the synthesis of antibody-lipid conjugates (ALCs) through site-selective acetylation of Lys 248 in human Immunoglobulin G (IgG) and the development of antibody-functionalized red blood cells (immunoRBC) for targeted drug delivery. ImmunoRBC with the HER2-selective antibody trastuzumab displayed on the surface (called Tras-RBC) was constructed following a three-step procedure. First, a peptide-guided, proximity-induced reaction transferred an azidoacetyl group to the ε-amino group of Lys 248 in the Fc domain. Second, the azide-modified IgG was subsequently conjugated with dibenzocyclooctyne (DBCO)-functionalized lipids via strain-promoted azide-alkyne cycloaddition (SPAAC) to result in ALCs. Third, the lipid portion of ALCs was then inserted into the cell membranes, and IgGs were displayed on red blood cells (RBCs) to construct immunoRBCs. We then loaded Tras-RBC with a photosensitizer (PS), Zinc phthalocyanine (ZnPc), to selectively target HER2-overexpressing cells, release ZnPc into cancer cells following photolysis, and induce photodynamic cytotoxicity in the cancer cells. This work showcases assembling immunoRBCs following site-selective lipid conjugation on therapeutic antibodies and the targeted introduction of PS into cancer cells. This method could apply to the surface functionalization of other membrane-bound vesicles or lipid nanoparticles for antibody-directed drug delivery., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Introduction: This study aims to provide a comprehensive assessment of economic and health-related quality of life (HRQoL) outcomes for human epidermal growth factor receptor 2 (HER2)-positive, early-stage breast cancer patients treated with trastuzumab-containing regimens, by focusing on both Incremental Cost-Effectiveness Ratios (ICERs) and quality-adjusted life years (QALYs)., Methods: A systematic search was conducted across PubMed, Embase, and Scopus databases without language or publication year restrictions. Two independent reviewers screened eligible studies, extracted data, and assessed methodology and reporting quality using the Drummond checklist and Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022), respectively. Costs were converted to US dollars (US$) for 2023 for cross-study comparison., Results: Twenty-two articles, primarily from high-income countries (HICs), were included, with ICERs ranging from US$13,176/QALY to US$254,510/QALY, falling within country-specific cost-effectiveness thresholds. A notable association was observed between higher QALYs and lower ICERs, indicating a favorable cost-effectiveness and health outcome relationship. EQ-5D was the most utilized instrument for assessing health state utility values, with diverse targeted populations., Conclusions: Studies reporting higher QALYs tend to have lower ICERs, indicating a positive relationship between cost-effectiveness and health outcomes. However, challenges such as methodological heterogeneity and transparency in utility valuation persist, underscoring the need for standardized guidelines and collaborative efforts among stakeholders., Registration: PROSPERO ID: CRD42021259826.

Background: The aim of this study was to explore the clinical utility of serum HER2 extracellular domain (sHER2 ECD) using data from a clinical trial evaluating trastuzumab combined S-1 plus oxaliplatin (SOX) in HER2 positive gastric cancer., Methods: sHER2 ECD were prospectively measured at baseline and subsequent treatment courses. Based on each quantile point of baseline sHER2 ECD levels and its early changes, patients were divided into two groups and compared clinical outcomes., Results: 43 patients were enrolled, and 17 patients (39.5%) were positive for baseline sHER2 ECD. Higher baseline sHER2 ECD levels tended to have lower hazard ratios (HRs). When divided into two groups by baseline sHER2 ECD of 19.1 ng/ml, median progression-free survival (PFS) and overall survival (OS) was longer in the higher group (mPFS: 16.8 vs 8.7 months, p = 0.359. mOS: 35.5 vs 20.6 months, p = 0.270), respectively. After initiation of treatment, sHER2 ECD significantly decreased up until the third cycle. Higher reduction rates of sHER2 ECD within 3 cycles also tended to have lower HRs. When divided into two groups by reduction rate of 42.5%, mPFS and mOS was longer in the higher reduced group (mPFS: 17.2 vs 8.7 months, p = 0.095. mOS: 65.0 vs 17.8 months, p = 0.047), respectively. Furthermore, higher reduction rates could surrogate higher objective response rates (ORR) (ORR: 90% vs 63.2% for 29.5%, p = 0.065. 100% vs 70% for 42.5%, p = 0.085), respectively., Conclusions: Baseline sHER2 ECD levels and its early decline may be useful biomarkers for SOX plus trastuzumab efficacy in HER2 positive gastric cancer., (© 2024. The Author(s).)

Background: Investigation of infection risk with subcutaneous versus intravenous trastuzumab and rituximab administration in an individual patient data (IPD) and published data meta-analysis of randomised controlled trials (RCTs)., Methods: Databases were searched to September 2021. Primary outcomes were serious and high-grade infection. Relative-risk (RR) and 95% confidence intervals (95%CI) were calculated using random-effects models., Results: IPD meta-analysis (6 RCTs, 2971 participants, 2320 infections) demonstrated higher infection incidence with subcutaneous versus intravenous administration, without reaching statistical significance (serious: 12.2% versus 9.3%, RR 1.28, 95%CI 0.93to1.77, P = 0.13; high-grade: 12.2% versus 9.9%, RR 1.32, 95%CI 0.98to1.77, P = 0.07). With exclusion of an outlying study in post-hoc analysis, increased risks were statistically significant (serious: 13.1% versus 8.4%, RR 1.53, 95%CI 1.14to2.06, P = 0.01; high-grade: 13.2% versus 9.3%, RR 1.56, 95%CI 1.16to2.11, P < 0.01). Published data meta-analysis (8 RCTs, 3745 participants, 648 infections) demonstrated higher incidence of serious (HR 1.31, 95%CI 1.02to1.68, P = 0.04) and high-grade (HR 1.52, 95%CI 1.17to1.98, P < 0.01) infection with subcutaneous versus intravenous administration., Conclusions: Results suggest increased infection risk with subcutaneous versus intravenous administration, although IPD findings are sensitive to exclusion of one trial with inconsistent results and identified risk-of-bias. Ongoing trials may confirm findings. Clinical surveillance should be considered when switching to subcutaneous administration. PROSPERO registration CRD42020221866/CRD42020125376., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: Current clinical practice recommends switching innovator intravenous trastuzumab (IV-TZM i ) to subcutaneous trastuzumab (SC-TZM) to save healthcare resources. However, with the availability of biosimilar intravenous trastuzumab (IV-TZM b ), there is a need to re-evaluate the recommendation. Hence, this study aims to compare the cost and resource use of SC-TZM and IV-TZM b in a Malaysian public healthcare facility., Methods: This activity-based costing study consists of (1) a retrospective medical record abstraction to determine patient details to estimate drug costs and (2) a time-motion study to quantify personnel time, patient time, and consumables used. The total cost of both SC-TZM and IV-TZM b were then compared using a cost-minimization approach, while differences were explored using an independent t-test. A sensitivity analysis was also conducted to determine the impact of uncertainties in the analysis., Results: The mean total cost of SC-TZM and IV-TZM b was USD 13,693 and USD 5,624 per patient respectively. The cost difference was primarily contributed by savings in drug cost of IV-TZM b , a reduction of USD 8,546 (SD = 134), p < 0.001 compared to SC-TZM. Interestingly, SC-TZM had a significantly lower cost than IV-TZM b for both the consumable and personnel cost, a reduction by USD 300 (SD = 17.6); p < 0.001 and USD 176 (SD = 7.3); p < 0.001 respectively. The sensitivity analysis demonstrated that the total cost difference between the formulation was mainly driven by drug costs., Conclusion: The study evidenced that IV-TZM b was a more economically viable option in Malaysian public healthcare currently compared to SC-TZM., (© 2023. The Author(s), under exclusive licence to Tehran University of Medical Sciences.)