Margenza (margetuximab-cmkb)

Margetuximab plus chemotherapy was used as fourth- or later-line treatment in patients who had received multiple HER2-targeted agents, including trastuzumab, pertuzumab, ado-trastuzumab emtansine, trastuzumab deruxtecan, tucatinib, and neratinib. Patients responded to margetuximab plus chemotherapy with real-world progression-free survival (PFS) of 3, 4, and 7 months. Clinical outcomes from three heavily pretreated patients with metastatic HER2+/HR+ MBC demonstrated that margetuximab plus chemotherapy resulted in real-world PFS comparable to that reported in the controlled pivotal clinical trial and support use of this targeted therapy option in appropriately identified patients.

The safety and efficacy of pertuzumab and margetuximab in the treatment of gastric cancer have been verified...Small-molecule tyrosine kinase inhibitors, such as lapatinib and pyrrotinib, have the advantages of small molecular weight, penetrating the blood-brain barrier and high oral bioavailability, and are expected to become the drugs of choice for perioperative treatment and neoadjuvant therapy of gastric cancer after validation by large-scale clinical trials in the future. Antibo-drug conjugate, such as T-DM1 and T-DXd, can overcome the resistance of monoclonal antibodies despite their different mechanisms of tumor killing, and are a supplement for the treatment of patients who have failed the treatment of monoclonal antibodies such as trastuzumab. Therefore, after more detailed stratification of gastric cancer patients, various gastric cancer drugs targeting HER2 are expected to play a more significant role.

P2, N=174, Active, not recruiting, Dana-Farber Cancer Institute | Recruiting --> Active, not recruiting | Trial primary completion date: Jul 2024 --> Oct 2024

P2/3; Trial completion date: Mar 2024 --> Jun 2025

Also, the findings of pharmacokinetic parameters such as Cmax, tmax, AUC0-∞, AUC0-t, and half-life results of margetuximab showed that the technique was helpful for accurately measuring drug concentrations in rat plasma. The method that was developed was useful and effective for quantifying margetuximab.

P2/3; Trial completion date: Dec 2023 --> Mar 2024 | Trial primary completion date: Dec 2023 --> Mar 2024

Primary endpoints were safety and maximum tolerated dose of tebotelimab when administered as a single agent (n = 269) or in combination with the anti-HER2 antibody margetuximab (n = 84). The confirmed objective response rate in these patients was 19% (14/72), including responses in patients typically not responsive to anti-HER2/anti-PD-1 combination therapy. ClinicalTrials.gov identifier: NCT03219268 .

Trastuzumab deruxtecan, an antibody drug conjugate of trastuzumab with a topoisomerase inhibitor, was recently approved for the treatment of refractory HER2-positive advanced GAC patients...Here we review the current status of HER2-targeted therapy in GACs. We additionally review newer therapies under investigation and their potential role in HER2 GACs.

More recently, two monoclonal antibodies have demonstrated their efficacy in combination with oxaliplatin-based first-line chemotherapy, nivolumab (anti-PD1) for PD-L1 CPS ≥5 tumors, and zolbetuximab for tumors overexpressing Claudin 18.2. Recent years have seen the emergence of new drugs that have improved patient survival, such as trastuzumab in first-line for HER2-positive tumors, ramucirumab alone or in combination with paclitaxel in second-line, and trifluridine-tipiracil beyond the second-line treatment. Advanced gastric adenocarcinoma is a common disease with a poor prognosis whose treatment has for decades been based on cytotoxic chemotherapy, including platinum salts in first-line, and taxane or irinotecan in second or later line. In addition, regorafenib has been also showed effective in phase 3 trial for heavily pretreated patients. Based on phase 2 studies, trastuzumab-deruxtecan was approved in 2022 by the EMA for HER2-positive pretreated patients. This agent is currently evaluated in phase 3 study (DESTINY-Gastric04 trial), as are several other anti-HER2 (zanidatamab, margetuximab, tucatinib), immune checkpoint inhibitors, or targeted therapies (anti-FGFR2b).

The PD-1 × LAG-3 bispecific molecule tebotelimab is safe as a monotherapy and in combination with margetuximab.

This concept was demonstrated in preclinical in vivo models showing increased efficacy of the combination therapy with the murine surrogate of BI-1607 and an anti-HER2, an anti–cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and an anti-CD20 (rituximab) as compared to monotherapy...The choice of trastuzumab as the combination agent in this trial was based on promising preclinical studies, a recognized need for additional options for those patients who fail to respond or stop responding to trastuzumab, and promising results from the newly approved Fc-engineered anti-HER2 mAb margetuximab...Phase 2a will enroll 15 subjects each in two cohorts of HER2+ advanced/metastatic breast cancer or HER2+ gastric/GEJ adenocarcinoma respectively. For information regarding the study, please contact: anna.ropenga@bioinvent.com

However, the advent of trastuzumab and more recently several other HER2-targeting novel therapies has led to significant improvements in the prognosis, making the diagnosis a "double-edged sword." The current standard first-line therapy for patients with HER2+ metastatic breast cancer (MBC) is a taxane combined with trastuzumab and pertuzumab. Trastuzumab deruxtecan should be used preferentially in the second line, with the only caveat being patients with CNS involvement where the tucatinib, capecitabine, and trastuzumab regimen could be considered...Options include margetuximab in combination with chemotherapy, neratinib + capecitabine, or trastuzumab + chemotherapy...Here, we provide an overview of the current and future management of HER2-positive advanced breast cancer and address the specific scenarios which may impact treatment selection including triple-positive breast cancer and the presence of brain metastases. Finally, we highlight promising novel treatments and ongoing trials that may impact future treatment sequencing.

No abstract available

Although these agents improve disease outcomes, HER2-positive metastatic breast cancer remains incurable and there is an unmet need for effective therapies in the later line setting. This review focuses on the development of margetuximab-cmkb, a novel, Fc-engineered, anti-HER2 monoclonal antibody, and its role in the systemic treatment of adult patients with metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease.

Current ERBB2 status may be more effective than archival status at predicting clinical benefit from margetuximab plus pembrolizumab therapy. ctDNA testing for ERBB2 status prior to treatment will spare patients from repeat tissue biopsies, which may be reserved for reflex testing when ctDNA is not detected.

Given the high rate of resistance, other HER2-targeted strategies have been developed, including monoclonal antibodies such as pertuzumab and margetuximab, trastuzumab-based antibody drug conjugates such as trastuzumab-emtansine (T-DM1) and trastuzumab-deruxtecan (T-DXd), and tyrosine kinase inhibitors like lapatinib and tucatinib, among others. When patients progress to multiple strategies, there are several HER2-targeted therapies available; however, treatment options are limited, and the potential combination with other drugs, immune checkpoint inhibitors, CAR-T cells, CAR-NK, CAR-M, and vaccines is an interesting and appealing field that is still in development. In this review, we will discuss the highlights and pitfalls of the different HER2-targeted therapies and potential combinations to overcome metastatic disease and resistance to therapy.

P1, N=353, Completed, MacroGenics | Active, not recruiting --> Completed

These models, designated ST4565C, ST4565D, STM148B, STM148C, STM148D, and ST4480B/EHR were developed and characterized for receptor expression, genomics, and drug sensitivities toward chemotherapies and targeted agents including T-DXd, T-DM1, and margetuximab. ST4565C/D was established from a patient with ER+/HER2+, metastatic BC who was T-DXd treatment naïve. ST4565C was collected post chemo- and HER2-targeted therapies; ST4565D was collected following eribulin/margetuximab... We established and characterized six breast XPDX models representing innate or acquired resistance to T-DXd. These models are valuable tools in understanding resistance mechanisms and in developing novel therapies for T-DXd-resistant patients.

This patient used paclitaxel-albumin plus trastuzumab and pertuzumab as the first-line therapy with progression-free survival (PFS) of 14 months, and pyrotinib in combined with vinorelbine as the second-line therapy with a PFS of 17 months. Then she received margetuximab plus capecitabine as the third-line treatment, the metastatic lesions in the liver were obviously shrunk, indicating clinical partial response and the PFS was 7 months. This case revealed that margetuximab plus chemotherapy may be an appropriate option for the patients who progressed after treating with anti-HER2 monoclonal antibodies and pyrotinib.

Among them, margetuximab demonstrated a significant improvement in progression-free survival compared with trastuzumab, when combined with chemotherapy in pretreated patients...Patient was then treated with pyrotinib, capecitabine and bisphosphonate for a period of 3 months...The patient received eight cycles of second-line therapy (vinorelbine plus margetuximab) from January 2021...This case demonstrates that margetuximab plus chemotherapy is safe and might bring clinical benefits for patients with HER2-positive breast cancer with liver metastasis. Further studies evaluating the efficacy and safety of margetuximab in Chinese HER2-positive breast cancer patients are needed.

Progress has been made by optimizing the fragment crystallizable (Fc) domain of trastuzumab, an IgG1 monoclonal, chimeric anti-HER2 antibody, to develop margetuximab. This review summarizes studies on the efficacy of margetuximab, discusses its utility as an anti-HER2 monoclonal antibody drug for the treatment of HER2 + BC, and presents the latest advances in the treatment of BC. This review provides insights into the clinical implication of margetuximab in HER2 + MBC treatment.

P3, N=624, Completed, MacroGenics | Active, not recruiting --> Completed

No abstract available

Final overall OS analysis did not demonstrate margetuximab advantage over trastuzumab. Margetuximab studies in patients with human epidermal growth factor receptor 2-positive breast cancer with different CD16A allelic variants are warranted.

The chemotherapy-free regimen of combined margetuximab/retifanlimab as first-line treatment in double biomarker-selected patients demonstrated a favorable toxicity profile compared with historical outcomes using chemotherapy plus trastuzumab. The ORR observed in this study compares favorably versus ORR observed with other chemotherapy-free approaches.

Currently available HER2-targeted agents include the monoclonal antibodies trastuzumab, pertuzumab, and margetuximab, the small-molecule inhibitors lapatinib, tucatinib, neratinib, and pyrotinib, as well as the antibody-drug conjugates trastuzumab emtansine and trastuzumab deruxtecan. This article addresses various challenging clinical situations when treating patients with HER2-positive ABC. The objective is to provide guidance to clinicians on how and when HER2-targeted therapies and additional treatments can be best implemented in routine clinical practice, on the basis of existing clinical evidence and expert opinion where needed.

The standard first-line treatment consists of taxane-based chemotherapy plus dual anti-HER2 therapies with trastuzumab and pertuzumab...Given a substantial advantage of another ADC, Fam-trastuzumab deruxtecan (T-DXd), compared to T-DM1 in a recent randomized trial in the second-line setting, T-DXd is currently the preferred second-line option...Tucatinib plus capecitabine and trastuzumab, lapatinib plus trastuzumab, neratinib or lapatinib plus capecitabine are some of the FDA approved combinations. Another newer agent approved for third- or later-line therapy in the metastatic setting is margetuximab, an Fc-engineered anti-HER2 monoclonal antibody, in combination with chemotherapy. Other novel agents currently under clinical trials are the drugs that indirectly target HER2, including immune cell cycle inhibitors, PI3K/mTOR inhibitors, and immunotherapy agents.

In the last five years, several new drugs have been approved for BC in the United States, many of which target HER2, including neratinib, margetuximab, tucatinib, and trastuzumab deruxtecan...Specific chemotherapy agents used were not always reported, but included taxanes, anthracyclines, cyclophosphamide, 5-fluorouracil, capecitabine, and carboplatin...HER2-targeted agents included trastuzumab emtansine, trastuzumab, pertuzumab, lapatinib, and neratinib...This meta-analysis provides a more comprehensive understanding of the most frequent AEs in this population by pooling patient data from several CTs and will contribute to better contextualize the safety of products used in this population. Future research including real-world studies can be used to better understand the safety profile of these medications.

And an 11 and 82% price reduction of margetuximab would make this regimen cost-effective in the US and China, respectively. In the US and China, margetuximab plus chemotherapy is not likely to be cost-effective for women with pretreated ERBB2-positive advanced breast cancer, whereas price reduction effectively improves insufficient cost-effectiveness.

HER2-targeted therapy is recommended for patients with HER2-positive advanced breast cancer, except for those with clinical congestive heart failure or significantly compromised left ventricular ejection fraction, who should be evaluated on a case-by-case basis. Trastuzumab, pertuzumab, and taxane for first-line treatment and trastuzumab deruxtecan for second-line treatment are recommended. In the third-line setting, clinicians should offer other HER2-targeted therapy combinations. There is a lack of head-to-head trials; therefore, there is insufficient evidence to recommend one regimen over another. The patient and the clinician should discuss differences in treatment schedule, route, toxicities, etc during the decision-making process. Options include regimens with tucatinib, trastuzumab emtansine, trastuzumab deruxtecan (if either not previously administered), neratinib, lapatinib, chemotherapy, margetuximab, hormonal therapy, and abemaciclib plus trastuzumab plus fulvestrant, and may offer pertuzumab if the patient has not previously received it. Optimal duration of chemotherapy is at least 4-6 months or until maximum response, depending on toxicity and in the absence of progression. HER2-targeted therapy can continue until time of progression or unacceptable toxicities. For patients with HER2-positive and estrogen receptor-positive or progesterone receptor-positive breast cancer, clinicians may recommend either standard first-line therapy or, for selected patients, endocrine therapy plus HER2-targeted therapy or endocrine therapy alone.Additional information is available at www.asco.org/breast-cancer-guidelines.

Also, more than threefolds of cell cycle arrest was observed at the optimal concentration synthetics, and 27.5% breast cancer cell apoptosis was detected after treatment with 100 nM nano-complex. These outputs have been indicating the potential capacity of synthesized nano-complex in inhibiting the growth of breast cancer cells.

P1; Active, not recruiting --> Completed

P2, N=0, Withdrawn, MedSIR | N=41 --> 0 | Not yet recruiting --> Withdrawn

Under current WTP threshold, margetuximab plus chemotherapy is not cost-effective compared with trastuzumab plus chemotherapy in pretreated patients with ERBB2-positive advanced breast cancer. Selecting CD16A-158F allele carriers might be a considerable option to optimize the cost-effectiveness of margetuximab.

Margetuximab is a chimeric and Fc-engineered monoclonal antibody directed to HER2 that can enhance the activation of the innate and adaptive immune responses while maintaining trastuzumab's antiproliferative effects. Ongoing studies are assessing the role of margetuximab in other settings and diseases such as early stage breast cancer and gastrointestinal malignancies. Here we review the rationale for the development of margetuximab, previous and ongoing clinical trials and current role in clinical practice.

P1, N=353, Active, not recruiting, MacroGenics | Trial completion date: Jul 2022 --> Jun 2023 | Trial primary completion date: May 2022 --> Mar 2023

P2/3 | N=81 | Active, not recruiting | Sponsor: MacroGenics | Recruiting --> Active, not recruiting | N=798 --> 81 | Trial completion date: May 2026 --> Dec 2023 | Trial primary completion date: May 2024 --> Dec 2023

P1; Trial completion date: Dec 2021 --> Jun 2022 | Trial primary completion date: Dec 2021 --> Jun 2022

Margetuximab enhances Fc-dependent ADCC in vitro more potently than the combination of pertuzumab (another approved mAb directed against an alternate HER2 epitope) and trastuzumab. Margetuximab administration also enhances HER2-specific B cell and T cell-mediated responses ex vivo in samples from patients treated with prior lines of HER2 antibody-based therapies. Stemming from these observations, a worthwhile future goal in the treatment of HER2+ breast cancer is to promote combinatorial approaches that better eradicate HER2+ cancer cells via enhanced immunological mechanisms.

Based on the results, the profile of variants in ERBB2 revealed more patients may profit from FDA-approval drugs in China. The patients with somatic mutations in ERBB2 are treated with trastuzumab deruxtecan and adotrastuzumab emtansine in NSCLC. The patients with amplification are treated with trastuzumab deruxtecan in most tumors, but margetuximab and chemotherapy can cure breast cancer, according to FDA-approval.

While trastuzumab and ado-trastuzumab emtansine (T-DM1) have become an integral part of treatment paradigms for HER2-positive cancer, the more recent approvals of the fam-trastuzumab deruxtecan (DS-8201) ADC and the Fc-engineered margetuximab antibody have highlighted the potential for continued improvement over existing HER2-targeting therapies. In cynomolgus monkeys, IKS014 was tolerated at 12 mg/kg single dose and 5 mg/kg repeat dose without ocular or lung toxicity findings.IKS014 was highly efficacious against HER2-positive tumor xenografts in vivo, including models with moderate target expression, and compared favorably to clinically validated benchmark ADCs. This improved preclinical efficacy combined with stable PK and good tolerability profile warrants further development of this novel ADC for HER2-positive cancers.

P2, N=41, Not yet recruiting, MedSIR