trastuzumab/pertuzumab (EG13084) / EirGenix - LARVOL DELTA

Adjuvant pertuzumab + trastuzumab vs trastuzumab monotherapy after pCR in early stage HER2-positive breast cancer (HOPA 2026) - "Adult patients were included if they had early stage high-risk HER2-positive breast cancer patients (T2 and/or N1), received neoadjuvant pertuzumab, trastuzumab, carboplatin and docetaxel (PTCH) therapy and had pCR (pathologic stage "ypT0/Tis ypN0") at the time of definitive surgery 1/1/2017 - 9/30/2025, aged 18 years or older, received at least four cycles/doses of pertuzumab in neoadjuvant setting, and had their surgery completed at OSU. This study aims to assess the impact of dual-HER2 directed therapy vs. trastuzumab alone in the adjuvant setting has an effect on cancer-related outcomes. Study findings could result in optimized application of adjuvant treatment regimens."

Clinical • Monotherapy • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2

Increasing Outpatient Infusion Efficiency with Subcutaneous Formulations (HOPA 2026) - "Background Daratumumab/hyaluronidase and pertuzumab/trastuzumab/hyaluronidase are non-hazardous chemotherapy drugs used for various cancers and conditions. The daratumumab/hyaluronidase study group did not yield a difference in time since the drug is used in combination with other drugs and pre-medications. The nursing preparation model offered a decrease in both preparation and administration costs with a combined savings of $2,787."

Clinical

Anthracycline-Free Neoadjuvant Pertuzumab-Trastuzumab-Taxane in Patients with HER2-Positive Early Breast Cancer: Hormone Receptor Status as a Key Determinant of Pathological Complete Response. (PubMed, Biomedicines) - " Anthracycline-free THP is a highly active, well-tolerated neoadjuvant option for HER2-positive EBC, with particularly high pCR rates in HR-negative disease. HR status emerged as a key determinant of pCR, whereas the role of PIK3CA mutations remains inconclusive and requires confirmation in larger prospective studies."

Journal • Breast Cancer • Hematological Disorders • HER2 Breast Cancer • HER2 Positive Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

Clinical Significance of Achieving No Evidence of Disease in HER2-Positive Metastatic Breast Cancer: A Multicenter Study by Turkish Oncology Group (TOG). (PubMed, Cancers (Basel)) - "Metastasis-directed local therapy and treatment regimen (trastuzumab vs. trastuzumab + pertuzumab) were not independently associated with NED attainment or PFS...Radiologic NED was independently associated with prolonged PFS within this enriched population. Factors associated with NED attainment included favorable ECOG performance status, HER2 IHC 3+ expression, and high tumor grade; given the wide confidence intervals, these estimates should be interpreted cautiously as exploratory and hypothesis-generating."

Clinical • Journal • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2

Overcoming Trastuzumab-Pertuzumab Resistance and Optimizing Sequential Anti-HER2 Therapy in HER2-Positive Metastatic Breast Cancer. (PubMed, Cancers (Basel)) - "Trastuzumab deruxtecan demonstrates substantial antitumor activity through potent cytotoxic effects and a bystander effect, supporting its efficacy in tumors with intratumoral heterogeneity or downstream pathway activation. In contrast, tucatinib-based regimens represent an important option for patients with brain metastases and tumors expressing p95HER2. The ongoing development of novel antibody-drug conjugates and bispecific antibodies is expected to further advance personalized sequential therapy targeting composite resistance mechanisms."

Journal • Review • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • ERBB3

Hormone Receptor Status as a Predictive Factor for Pathological Complete Response to Neoadjuvant Dual HER2 Blockade in Patients with HER2-Positive Breast Cancer: A Multicenter Retrospective Study. (PubMed, Breast Care (Basel)) - "Neoadjuvant therapy with dual human epidermal growth factor receptor 2 (HER2) blockade using trastuzumab and pertuzumab combined with chemotherapy is the standard of care for patients with locally advanced HER2-positive breast cancer...HR status is a strong and independent predictor of pCR in HER2-positive breast cancer patients receiving neoadjuvant dual blockade. Patients with HR- disease derive the most benefit from this regimen, highlighting the need for tailored therapeutic strategies to improve outcomes for the HR+ subgroup."

Biomarker • Journal • Retrospective data • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2

Trastuzumab Deruxtecan plus Pertuzumab for HER2-Positive Metastatic Breast Cancer. (PubMed, N Engl J Med) - P3 | "Trastuzumab deruxtecan plus pertuzumab led to a significantly lower risk of progression or death than THP when used as first-line treatment for HER2-positive advanced or metastatic breast cancer, with no new safety signals. (Funded by AstraZeneca and Daiichi Sankyo; DESTINY-Breast09 ClinicalTrials.gov number, NCT04784715.)."

Journal • Breast Cancer • Hematological Disorders • HER2 Breast Cancer • HER2 Positive Breast Cancer • Interstitial Lung Disease • Leukopenia • Neutropenia • Oncology • Pneumonia • Pulmonary Disease • Respiratory Diseases • Solid Tumor • HER-2

A Phase III Study of KN026 in Combination With HB1801 as Adjuvant Therapy for Resectable HER2-Positive Breast Cancer (clinicaltrials.gov) - P3 | N=1800 | Not yet recruiting | Sponsor: Shanghai JMT-Bio Inc.

New P3 trial • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2

Radiation Therapy Followed by Intrathecal (IT) Trastuzumab/Pertuzumab in the Management of HER2+ Breast Leptomeningeal Disease: Interim Results from a Phase II Multi-Institutional Study (SABCS 2025) - P1/2 | "The study met its predetermined endpoint for OS to warrant continuing enrollment in the second stage of the phase II trial. Initial trial results are encouraging with study therapy that is well tolerated."

Clinical • P2 data • Breast Cancer • HER-2

Phase III study of paclitaxel/carboplatin alone or combined with either trastuzumab and hyaluronidase-oysk or pertuzumab, trastuzumab, and hyaluronidase-zzxf in HER2 positive, stage I-IV endometrial carcinoma (NRG-GY026) (SGO 2026) - No abstract available

P3 data • Endometrial Cancer • Oncology • Solid Tumor • HER-2

IPATHER: Ipatasertib + Pertuzumab +Trastuzumab in Advanced HER2+ PI3KCA-mutant Breast Cancer Patients (clinicaltrials.gov) - P1 | N=17 | Completed | Sponsor: SOLTI Breast Cancer Research Group | Recruiting ➔ Completed

Trial completion • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PGR • PIK3CA

EmpowHER 208: A Phase 2, randomized, multicenter, open-label neoadjuvant study evaluating zanidatamab in combination with chemotherapy in participants with HER2-positive breast cancer combination with chemotherapy in participants with HER2-positive breast cancer (clinicaltrialsregister.eu) - P1/2 | N=60 | Not yet recruiting | Sponsor: Jazz Pharmaceuticals Ireland Limited

New P1/2 trial • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Hormone Receptor Negative Breast Cancer • Inflammatory Breast Cancer • Oncology • Solid Tumor • HER-2

Multiplex Spatial Proteomic Analysis of HER2-Positive Breast Tumors Reveals Unique Molecular and Immunologic Features Associated With Treatment Response. (PubMed, JCO Precis Oncol) - "ER-negative, HER2-positive breast cancer has unique molecular and immunologic features that may predict pCR after neoadjuvant HP. Validation of these potential biomarkers and composite biomarker analyses may guide design of future clinical trials."

Journal • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Hormone Receptor Breast Cancer • Oncology • Solid Tumor • EGFR • ER • HER-2

Real-World Outcomes of First-Line Pertuzumab, Trastuzumab, and Taxane in HER2-Positive Metastatic Breast Cancer in Costa Rica: A Multicenter Retrospective Study. (PubMed, Cureus) - "Paclitaxel was the most used taxane (85%). These findings contribute to regional real-world evidence and underscore the need for neurological monitoring, given the high rate of central nervous system (CNS) progression. Cross-study comparisons remain descriptive due to population and design differences."

Journal • Real-world evidence • Retrospective data • Breast Cancer • Cardiovascular • HER2 Breast Cancer • HER2 Positive Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Pain • Solid Tumor • HER-2

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=256 | Recruiting | Sponsor: Genentech, Inc. | N=104 ➔ 256 | Trial completion date: Dec 2020 ➔ Nov 2022 | Trial primary completion date: Dec 2020 ➔ Nov 2022

Enrollment change • Trial completion date • Trial primary completion date • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=256 | Active, not recruiting | Sponsor: Genentech, Inc. | Recruiting ➔ Active, not recruiting

Enrollment closed • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=104 | Recruiting | Sponsor: Genentech, Inc. | N=236 ➔ 104 | Trial completion date: Dec 2021 ➔ Dec 2020 | Trial primary completion date: Dec 2021 ➔ Dec 2020

Enrollment change • Trial completion date • Trial primary completion date • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=236 | Recruiting | Sponsor: Genentech, Inc. | Trial completion date: Feb 2020 ➔ Dec 2021 | Trial primary completion date: Feb 2020 ➔ Dec 2021

Trial completion date • Trial primary completion date • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=256 | Recruiting | Sponsor: Genentech, Inc. | Trial completion date: Dec 2022 ➔ Nov 2024 | Trial primary completion date: Nov 2022 ➔ Nov 2024

Trial completion date • Trial primary completion date • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=156 | Recruiting | Sponsor: Hoffmann-La Roche

New P1 trial • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

GO39374: To Evaluate the Safety, Tolerability, and Pharmacokinetics of Inavolisib Single Agent in Participants With Solid Tumors and in Combination With Endocrine and Targeted Therapies in Participants With Breast Cancer (clinicaltrials.gov) - P1 | N=200 | Active, not recruiting | Sponsor: Genentech, Inc. | Trial completion date: Nov 2024 ➔ Dec 2026 | Trial primary completion date: Nov 2024 ➔ Dec 2026

Trial completion date • Trial primary completion date • Breast Cancer • HER2 Breast Cancer • Hormone Receptor Breast Cancer • Hormone Receptor Positive Breast Cancer • Oncology • Solid Tumor • HER-2 • PIK3CA

BRIDGING HER2 TESTING AND TREATMENT: REAL-WORLD EVIDENCE ACROSS 22 SOLID TUMORS (ISPOR 2026) - "Although HER2 is expressed in multiple solid tumors and testing has increased dramatically, HER2-targeted therapies are only prescribed in 38% of patients and newer generation HER2-targeted therapies are not frequently utilized. Future research will focus on how HER2 scoring (breast vs. gastric), HER2 testing methodologies (i.e."

Clinical • HEOR • Real-world • Real-world evidence • Endometrial Cancer • Oncology • Solid Tumor • HER-2

A HEALTH ECONOMIC AND ENVIRONMENTAL EVALUATION OF SUBCUTANEOUS PERTUZUMAB/TRASTUZUMABVERSUS INTRAVENOUS PERTUZUMAB/TRASTUZUMAB FOR HER2-POSITIVE BREAST CANCER IN DENMARK (HEREAFTER) (ISPOR 2026) - "Implementing SC PT in a hospital outpatient setting has the potential to free up resources and increase capacity by reducing the number of hours spent by HCPs, while simultaneously lowering the environmental and economic costs."

HEOR • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2

ECONOMIC EVALUATION OF FIXED-DOSE SUBCUTANEOUS PERTUZUMAB-TRASTUZUMAB FOR NEOADJUVANT TREATMENT OF HIGH-RISK HER2-POSITIVE EARLY BREAST CANCER IN INDONESIA (ISPOR 2026) - "In the Indonesian setting, pertuzumab plus trastuzumab administered subcutaneously in combination with chemotherapy considered cost effective compared to chemotherapy alone. The intervention appears most economically advantageous for women diagnosed at age 35."

Clinical • HEOR • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2

Antibody-based adjuvant and neoadjuvant therapy for early non-metastatic HER2-positive breast cancer: a 2010–2020 analysis from the Bavarian cancer registry, Regensburg (DKK 2026) - "This retrospective cohort study assessed survival (OS), recurrence-free survival (RFS), and pathological complete response (pCR) in patients receiving anthracycline-based versus anthracycline-free regimens, and dual Trastuzumab+Pertuzumab therapy versus Trastuzumab alone. Dual HER2 blockade and anthracycline-free regimens represent effective treatment strategies supported by real-world evidence."

Clinical • Metastases • Breast Cancer • HER2 Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • HER-2