Safety and efficacy study of metronomic vinorelbine, cyclophosphamide plus capecitabine in metastatic breast cancer: A phase II trial

Metronomic chemotherapy plus anti-PD-1 in metastatic breast cancer: a Bayesian adaptive randomized phase 2 trial

It remains unclear whether metronomic chemotherapy is superior to conventional chemotherapy when combined with immune checkpoint blockade. Here we performed a phase 2 clinical trial of metronomic chemotherapy combined with PD-1 blockade to compare the efficacy of combined conventional chemotherapy and PD-1 blockade using Bayesian adaptive randomization and efficacy monitoring. Eligible patients had metastatic HER2-negative breast cancer and had not received more than one prior line of standard chemotherapy. Patients (total n = 97) were randomized to receive (1) metronomic vinorelbine (NVB) monotherapy (n = 11), (2) NVB plus anti-PD-1 toripalimab (n = 7), (3) anti-angiogenic bevacizumab, NVB and toripalimab (n = 27), (4) conventional cisplatin, NVB and toripalimab (n = 26), or (5) metronomic cyclophosphamide, capecitabine, NVB and toripalimab (the VEX cohort) (n = 26). The primary endpoint was disease control rate (DCR). Secondary objectives included progression-free survival (PFS) and safety. The study met the primary endpoint. The VEX (69.7%) and cisplatin (73.7%) cohorts had the highest DCR. The median PFS of patients in the VEX cohort was the longest, reaching 6.6 months, followed by the bevacizumab (4.0 months) and cisplatin (3.5 months) cohorts. In general, the five regimens were well tolerated, with nausea and neutropenia being the most common adverse events. An exploratory mass cytometry analysis indicated that metronomic VEX chemotherapy reprograms the systemic immune response. Together, the clinical and translational data of this study indicate that metronomic VEX chemotherapy combined with PD-1 blockade can be a treatment option in patients with breast cancer. ClinicalTrials.gov Identifier: NCT04389073 .

Optimizing cancer therapy: a review of the multifaceted effects of metronomic chemotherapy

Metronomic chemotherapy (MCT), characterized by the continuous administration of chemotherapeutics at a lower dose without prolonged drug-free periods, has garnered significant attention over the last 2 decades. Extensive evidence from both pre-clinical and clinical settings indicates that MCT induces distinct biological effects than the standard Maximum Tolerated Dose (MTD) chemotherapy. The low toxicity profile, reduced likelihood of inducing acquired therapeutic resistance, and low cost of MCT render it an attractive chemotherapeutic regimen option. One of the most prominent aspects of MCT is its anti-angiogenesis effects. It has been shown to stimulate the expression of anti-angiogenic molecules, thereby inhibiting angiogenesis. In addition, MCT has been shown to decrease the regulatory T-cell population and promote anti-tumor immune response through inducing dendritic cell maturation and increasing the number of cytotoxic T-cells. Combination therapies utilizing MCT along with oncolytic virotherapy, radiotherapy or other chemotherapeutic regimens have been studied extensively. This review provides an overview of the current status of MCT research and the established mechanisms of action of MCT treatment and also offers insights into potential avenues of development for MCT in the future.

Efficacy of Metronomic Oral Vinorelbine, Cyclophosphamide, and Capecitabine vs Weekly Intravenous Paclitaxel in Patients With Estrogen Receptor-Positive, ERBB2-Negative Metastatic Breast Cancer: Final Results From the Phase 2 METEORA-II Randomized Clinical Trial

Importance

In spite of the effectiveness of endocrine therapy plus cyclin-dependent kinase (CDK) 4/6 inhibitors as the first-line treatment for estrogen receptor (ER)-positive, erb-b2 receptor tyrosine kinase 2 (ERBB2 [formerly HER2/neu])-negative (ER+/ERBB2-) metastatic breast cancer (MBC), patients eventually develop resistance, and eventually most will receive chemotherapy. The METEORA-II trial compared a metronomic all-oral treatment with intravenous (IV) chemotherapy.

Objective

To compare the efficacy of the oral vinorelbine plus cyclophosphamide plus capecitabine (VEX) regimen vs weekly IV paclitaxel among patients with ER+/ERBB2- MBC who are candidates for chemotherapy.

Design, Setting, and Participants

This phase 2 randomized clinical trial including 140 women 18 years and older (randomized 1:1) with ER+/ERBB2- MBC was carried out from September 13, 2017, to January 14, 2021 at 15 centers in Italy. Eligible patients could have received 1 prior line of chemotherapy for MBC and/or 2 lines of endocrine therapy (including CDK4/6 inhibitors).

Interventions

In 4-week cycles, patients received either metronomic oral VEX or weekly IV paclitaxel.

Main Outcomes and Measures

The primary end point was investigator-assessed time to treatment failure (TTF) defined as the interval between the date of randomization to the end of treatment (because of disease progression or lack of tolerability or because further trial treatment was declined). Secondary end points included progression-free survival (PFS), overall survival (OS), and disease control rate (complete or partial response or stable disease lasting for at least 24 weeks).

Results

In total, 133 patients received either VEX (n = 70) or paclitaxel (n = 63) in 4-weekly cycles. The median age was 61 (range, 30-80) years. The VEX treatment significantly prolonged TTF vs paclitaxel (hazard ratio [HR], 0.61; 95% CI, 0.42-0.88; P = .008), median TTF was 8.3 (95% CI, 5.6-11.1) months for VEX vs 5.7 (95% CI, 4.1-6.1) months for paclitaxel, and the 12-month TTF was 34.3% for VEX vs 8.6% for paclitaxel. The median PFS was 11.1 (95% CI, 8.3-13.8) months vs 6.9 (95% CI, 5.4-10.1) months favoring VEX (HR, 0.67; 95% CI, 0.46-0.96, P = .03). The 12-month PFS was 43.5% for VEX vs 21.9% for paclitaxel. No difference in OS was found. The TF event for 55.6% of patients was progression of disease; for 23% it was AEs. More patients assigned to VEX had at least 1 grade 3 or 4 targeted adverse event (VEX, 42.9%; 95% CI, 31.1%-55.3% vs paclitaxel, 28.6%; 95% CI, 17.9%-41.3%), but essentially no alopecia.

Conclusion and Relevance

This randomized clinical trial found significantly prolonged TTF and PFS for oral VEX but no improvement in OS compared with intravenous paclitaxel, despite increased but still manageable toxic effects. The VEX regimen may provide more prolonged disease control than weekly paclitaxel for ER+/ERBB2- MBC.

Trial Registration

ClinicalTrials.gov Identifier: NCT02954055.

A phase II study of a doublet metronomic chemotherapy regimen consisting of oral vinorelbine and capecitabine in Chinese women with HER2-negative metastatic breast cancer

BACKGROUND

This single-arm prospective phase II trial was performed to assess the efficacy and safety of the dual oral metronomic vinorelbine and capecitabine (mNC) regimen in women with HER2-negative metastatic breast cancer (MBC) in China.

METHODS

The mNC regimen was administered to the enrolled cases, including oral vinorelbine (VNR) 40 mg three times weekly (on days 1, 3 and 5 every week) and capecitabine (CAP) 500 mg three times a day, until disease progression or intolerable toxicity. The primary endpoint was the 1-year progression-free survival (PFS) rate. Secondary endpoints included objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR) and treatment-related adverse events (TRAEs). Stratified factors included treatment lines and hormone receptor (HR) status.

RESULTS

Between June 2018 and March 2023, 29 patients were enrolled into the study. The median follow-up time was 25.4 months (range, 2.0-53.8). In the entire group, the 1-year PFS rate was 54.1%. ORR, DCR and CBR were 31.0%, 96.6% and 62.1%, respectively. The mPFS was 12.5 months (range, 1.1-28.1). Subgroup analysis revealed that ORRs were 29.4% and 33.3% in first- and ≥second-line chemotherapy, respectively. ORRs were 29.2% (7/24) and 40.0% (2/5) for HR-positive MBC and metastatic triple-negative breast cancer (mTNBC), respectively. Grade 3/4 TRAEs were neutropenia (10.3%) and nausea/vomiting (6.9%).

CONCLUSIONS

The dual oral mNC regimen showed very good safety features and improved compliance without loss of efficacy in both first- and second-line treatments. The regimen also reached an excellent ORR in the mTNBC subgroup.

Metronomic Chemotherapy for Metastatic Breast Cancer Treatment: Clinical and Preclinical Data between Lights and Shadows

Metronomic chemotherapy (mCHT), defined as continuous administration of low-dose chemotherapeutic agents with no or short regular treatment-free intervals, was first introduced to the clinic in international guidelines in 2017, and, since then, has become one of the available strategies for the treatment of advanced breast cancer (ABC). Despite recent successes, many unsolved practical and theoretical issues remain to be addressed. The present review aims to identify the "lights and shadows" of mCHT in preclinical and clinical settings. In the preclinical setting, several findings indicate that one of the most noticeable effects of mCHT is on the tumor microenvironment, which, over the last twenty years, has been demonstrated to be pivotal in supporting tumor cell survival and proliferation. On the other hand, the direct effects on tumor cells have been less well-defined. In addition, critical items to be addressed are the lack of definition of an optimal biological dose (OBD), the method of administration of metronomic schedules, and the recognition and validation of predictive biomarkers. In the clinical context-where mCHT has mainly been used in a metastatic setting-low toxicity is the most well-recognised light of mCHT, whereas the type of study design, the absence of randomised trials and uncertainty in terms of doses and drugs remain among the shadows. In conclusion, growing evidence indicates that mCHT is a suitable treatment option for selected metastatic breast cancer (MBC) patients. Moreover, given its multimodal mechanisms of action, its addition to immunological and targeted therapies might represent a promising new approach to the treatment of MBC. More preclinical data are needed in this regard, which can only be obtained through support for translational research as the key link between basic science and patient care.

The prolonged clinical benefit with metronomic chemotherapy (VEX regimen) in metastatic breast cancer patients

Metronomic chemotherapy is a treatment option for metastatic breast cancer (MBC) patients who require prolonged disease control without cumulative toxicity. Data available on the efficacy and tolerability of prolonged usage of metronomic therapy are limited. We analyzed patients with MBC, enrolled in a clinical trial, who obtained a prolonged clinical benefit for a duration of at least 12 months with vinorelbine 30 or 40 mg orally three times a week, cyclophosphamide 50 mg daily and capecitabine 500 mg three times a day (VEX regimen). The patients were treated at the European Institute of Oncology, Milan. We identified 67 MBC patients. The median age before starting the VEX regimen was 53 years. There were 59 patients (88%) who had hormone-receptors positive and HER2 negative BC. We had 37 patients who received VEX as the first-line treatment for MBC, while 30 patients were pretreated. The objective response rate was 49% (95% CI, 37-62). The median duration of VEX treatment after the first year was 14 months (min-max range 0.3-81.3 months). The progression-free survival at 3 years was 25.4% (95% CI, 15.7-36.2) and at 4 years was 18.5% (95% CI, 10.1-28.8 time 0 corresponds to 1 year after starting VEX). A total of 25 patients required a dose reduction, 7% of patients experienced G3 hand and foot syndrome. Metronomic VEX regimen can induce prolonged clinical benefit in MBC. On the basis of this long-term safety evaluation, there is no evidence of specific cumulative or delayed toxicities with metronomic chemotherapy.

Metronomic Chemotherapy for Metastatic Breast Cancer

BACKGROUND

As disease control and quality of life play a leading role in metastatic breast cancer (MBC), metronomic chemotherapy (MCT) is gaining popularity alongside conventional chemotherapy (CCT) and targeted therapies.

SUMMARY

MCT, defined as continuous administration of low-dose chemotherapeutic agents, is accepted as a therapy that exerts its effects via immunomodulation, anti-angiogenesis and direct cytotoxic effects. Oral administration of MCT is safe, easy to handle, and allows for flexible drug dosing. Dose accumulations associated with non-tolerable side effects are rare, so the medication can be administered for longer periods of time. Patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic disease resistant to endocrine-based therapy and not requiring rapid tumor response are generally suitable for MCT. However, MCT may also be promising in patients with triple-negative and HER2-positive tumors without aggressive disease who prefer a lower toxicity profile compared to CCT. The most commonly used agents are cyclophosphamide (CTX), methotrexate (MTX), capecitabine (CAPE), and vinorelbine (VRL), whereby a combination of agents is frequently applied. Key Messages: Based on the growing body of evidence, MCT can be considered as a suitable treatment option in selected MBC patients. Nevertheless, there is an urgent need for randomized controlled trials comparing MCT with CCT, but also with best supportive care. Due to the multimodal mechanisms of action, the combination with targeted and immunological therapies may represent a new promising approach for the treatment of MBC.

Metronomic Therapy in Oral Squamous Cell Carcinoma

Metronomic therapy is characterized by drug administration in a low-dose, repeated, and regular manner without prolonged drug-free interval. The two main anticancer mechanisms of metronomic therapy are antiangiogenesis and immunomodulation, which have been demonstrated in several delicate in vitro and in vivo experiments. In contrast to the traditional maximum tolerated dose (MTD) dosing of chemotherapy, metronomic therapy possesses comparative efficacy but greatlydecreases the incidence and severity of treatment side-effects. Clinical trials of metronomic anticancer treatment have revealed promising results in a variety cancer types and specific patient populations such as the elderly and pediatric malignancies. Oral cavity squamous cell carcinoma (OCSCC) is an important health issue in many areas around the world. Long-term survival is about 50% in locally advanced disease despite having high-intensity treatment combined surgery, radiotherapy, and chemotherapy. In this article, we review and summarize the essence of metronomic therapy and focus on its applications in OCSCC treatment.

Phase II study of metronomic treatment with daily oral vinorelbine as first-line chemotherapy in patients with advanced/metastatic HR+/HER2- breast cancer resistant to endocrine therapy: VinoMetro-AGO-B-046

Purpose

Metronomic chemotherapy (MCT) is an increasingly used treatment option in hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2−) advanced/metastatic breast cancer (MBC) after failure of endocrine-based therapies.

Methods

VinoMetro was a multicentre, open-label, single-arm, phase II study of metronomic oral vinorelbine (VRL; 30 mg/day) as a first-line chemotherapy (CT) in patients with HR+/HER2− MBC after endocrine failure. The primary endpoint was the clinical benefit rate (CBR) at 24 weeks.

Results

Between January 2017 and April 2019, nine patients were enrolled. The CBR was 22.2% (90% confidence interval [CI] 4.1–55.0), p = 0.211. The median progression-free survival (PFS) was 12.0 weeks (95% CI 11.3–12.7). Grade 3–4 adverse events (AEs) occurred in 22.2% of patients. One patient died of febrile neutropenia.

Conclusion

VinoMetro (AGO-B-046) was closed early after nine patients and occurrence of one grade 5 toxicity in agreement with the lead institutional review board (IRB). Metronomic dosing of oral VRL in HR+/HER2− MBC as first-line CT after failure of endocrine therapies showed only limited benefit in this population.

Trial registration number and date of registration

ClinicalTrials.gov Identifier: NCT03007992; December 15, 2016.

Effect of Capecitabine Maintenance Therapy Using Lower Dosage and Higher Frequency vs Observation on Disease-Free Survival Among Patients With Early-Stage Triple-Negative Breast Cancer Who Had Received Standard Treatment: The SYSUCC-001 Randomized Clinical Trial

IMPORTANCE

Among all subtypes of breast cancer, triple-negative breast cancer has a relatively high relapse rate and poor outcome after standard treatment. Effective strategies to reduce the risk of relapse and death are needed.

OBJECTIVE

To evaluate the efficacy and adverse effects of low-dose capecitabine maintenance after standard adjuvant chemotherapy in early-stage triple-negative breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial conducted at 13 academic centers and clinical sites in China from April 2010 to December 2016 and final date of follow-up was April 30, 2020. Patients (n = 443) had early-stage triple-negative breast cancer and had completed standard adjuvant chemotherapy.

INTERVENTIONS

Eligible patients were randomized 1:1 to receive capecitabine (n = 222) at a dose of 650 mg/m2 twice a day by mouth for 1 year without interruption or to observation (n = 221) after completion of standard adjuvant chemotherapy.

MAIN OUTCOMES AND MEASURES

The primary end point was disease-free survival. Secondary end points included distant disease-free survival, overall survival, locoregional recurrence-free survival, and adverse events.

RESULTS

Among 443 women who were randomized, 434 were included in the full analysis set (mean [SD] age, 46 [9.9] years; T1/T2 stage, 93.1%; node-negative, 61.8%) (98.0% completed the trial). After a median follow-up of 61 months (interquartile range, 44-82), 94 events were observed, including 38 events (37 recurrences and 32 deaths) in the capecitabine group and 56 events (56 recurrences and 40 deaths) in the observation group. The estimated 5-year disease-free survival was 82.8% in the capecitabine group and 73.0% in the observation group (hazard ratio [HR] for risk of recurrence or death, 0.64 [95% CI, 0.42-0.95]; P = .03). In the capecitabine group vs the observation group, the estimated 5-year distant disease-free survival was 85.8% vs 75.8% (HR for risk of distant metastasis or death, 0.60 [95% CI, 0.38-0.92]; P = .02), the estimated 5-year overall survival was 85.5% vs 81.3% (HR for risk of death, 0.75 [95% CI, 0.47-1.19]; P = .22), and the estimated 5-year locoregional recurrence-free survival was 85.0% vs 80.8% (HR for risk of locoregional recurrence or death, 0.72 [95% CI, 0.46-1.13]; P = .15). The most common capecitabine-related adverse event was hand-foot syndrome (45.2%), with 7.7% of patients experiencing a grade 3 event.

CONCLUSIONS AND RELEVANCE

Among women with early-stage triple-negative breast cancer who received standard adjuvant treatment, low-dose capecitabine maintenance therapy for 1 year, compared with observation, resulted in significantly improved 5-year disease-free survival.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01112826.

Metronomic therapy in advanced breast cancer and NSCLC: vinorelbine as a paradigm of recent progress

INTRODUCTION

Metronomic chemotherapy (MCT) is based on frequent dosing of the drug. . This leads to pharmacologically active but low plasma concentrations that reduce toxicity. MCT seems to work primarily via indirect effects on tumor cells and their microenvironment, rather than direct antitumor effects. Oral vinorelbine is one of the most widely studied MCT approaches in both advanced breast cancer and non-small cell lung cancer.

EXPERT OPINION

MCT with vinorelbine has proven efficacy, tolerability and quality of life benefits both as monotherapy and in combination with other MCTs or targeted agents, in first-line therapy and in previously treated patients. Key populations are emerging who may be particularly well suited to metronomic vinorelbine, including those with indolent disease, older individuals, and those with multiple comorbidities and/or bone metastases. Ongoing trials should help to further delineate these target groups. Additional work is needed to better understand the optimal vinorelbine regimen, particularly when used in combination or in non-Caucasian patients. Markers are also required to help identify individuals who are most likely to respond. Nonetheless, the efficacy and tolerability of MCT, allied to improved patient convenience, reduced need for medical engagement and lower cost, make it an appealing option - particular in resource-constrained healthcare environments.

Metronomic capecitabine as maintenance treatment after first line induction with XELOX for metastatic colorectal cancer patients

Maintenance treatment after first-line chemotherapy for patients with metastatic colorectal cancer (mCRC) is a priority strategy. However, which medicine is chosen is controversial. This study aimed to determine the efficacy and safety of maintenance treatment with metronomic capecitabine vs observation.In this randomized controlled trial, patients who completed 18 weeks of induction chemotherapy with XELOX and achieved disease control were randomly assigned centrally (1:1) to receive maintenance therapy with metronomic chemotherapy or observation until disease progression. The primary endpoint was progression-free survival from randomization; secondary endpoints included overall survival and safety. Analyses were performed by intention to treat.Between January 1st, 2017 and December 31th 2018, 48 patients were enrolled and randomly assigned to receive maintenance treatment with metronomic capecitabine (n = 25) or only observation (n = 23). The median progression-free survival in the metronomic capecitabine group was 5.66 (95% confidence interval [CI] 5.25-6.07) months vs 3.98 (95%CI 3.71-4.24) months in the observation group (hazard ratio 0.11, 95% [CI] 0.04-0.26, P = .000). There was no statistically significant difference in median overall survival: 23.82 (95% CI 22.38-25.25) months in the metronomic capecitabine group vs 21.81 (95% CI 20.23-23.38) months in the observation group (hazard ratio 0.49, 95% CI 0.21-1.11, P = .087). Subgroup analyses were generally consistent with the primary finding. Similar safety profiles were observed in both arms. The most frequent adverse events in metronomic capecitabine group included neutropenia, diarrhea, hand-foot skin reaction, and mucositis.Maintenance therapy with metronomic capecitabine can be considered an alternative option following first-line chemotherapy of XELOX in patients with metastatic colorectal cancer with controlled toxicities.

A Dose-finding Study of Metronomic Oral Vinorelbine in Combination With Oral Cyclophosphamide and Bevacizumab in Patients With Advanced Breast Cancer

BACKGROUND

Metronomic chemotherapy can induce disease control in patients with metastatic breast cancer (MBC) and has better safety profiles than conventional chemotherapy. Evidence suggests that cytotoxics can be anti-angiogenic in pre-clinical models and may have synergistic effects when combined with anti-vascular endothelial growth factor therapies.

PATIENTS AND METHODS

Patients pretreated with ≥ 1 prior line of therapy for MBC received oral cyclophosphamide 50 mg daily in combination with oral vinorelbine at escalating doses of 20 mg (V20), 30 mg (V30), and 40 mg (V40) 3 times per week, and intravenous bevacizumab 15 mg/kg every 3 weeks. Patients with human epidermal growth factor receptor 2-positive disease were given the same regimen plus standard trastuzumab. Doses were escalated when 3 patients completed 3 treatment cycles of V20 and V30, without experiencing dose-limiting toxicities. The recommended dose was then tested in a further 6 patients. Circulating tumour cells and circulating endothelial cells (CEC) were measured in 30 mL of whole blood samples at baseline, after cycle 1, and at the disease progression.

RESULTS

Fifteen patients were recruited from June 2013 to October 2015. The median age was 61 years (range, 29-72 years); 80% had estrogen receptor-positive and 33% had human epidermal growth factor receptor 2-positive disease. At least 67% had visceral metastases, and 80% had received ≥ 2 lines of prior treatment. No dose-limiting toxicities were observed at the 3 dose-levels, making V40 the recommended dose. Overall 8 (53%) patients developed grade 2 adverse events (arthralgia, n = 3 [20%]; asthenia, n = 2 [13%]; diarrhea, n = 2 [13%]; leukopenia, n = 2 [13%]). Bevacizumab was associated with grade 3 hypertension (n = 3 [20%]). Stable disease as best response was observed in 11 (73.3%) patients. The clinical benefit rate was 66.6% (10/15 patients). The median time to progression was 6.9 months. At baseline, CECs were more commonly detectable than circulating tumor cells; however, no statistical correlation was found between CEC kinetics and response.

CONCLUSION

A metronomic vinorelbine dose of 40 mg combined with cyclophosphamide and bevacizumab is a promising treatment regimen in pretreated patients with MBC.

Recent clinical evidence on metronomic dosing in controlled clinical trials: a systematic literature review

Introduction: Metronomic dosing is used to give continuous chemotherapy at low doses. The low doses have minimal side effects and may enable cancer treatment to be remodeled toward the management of chronic disease.Methods: We searched PubMed database to obtain relevant clinical trials studying metronomic chemotherapy (MCT). Our main focus was to find controlled phase II and phase III trials.Results: This systematic review summarizes the results of 91 clinical reports focusing on randomized phase II and phase III clinical studies between 2012 and 2018. During that time, nine randomized phase II and 10 randomized phase III studies were published. In the majority of the studies, MCT was well tolerated, and major side effects were rarely seen. Altogether, 4 phase III studies and 4 randomized phase II studies presented positive results and some clinical benefit.Discussion: Most of the studies did not show significantly improved overall survival or progression-free survival. Typically, the metronomic dosing was explored in a maintenance setup and was added to other agents given within normal high doses, whereas no trial was performed challenging metronomic dosing and best supportive care in later treatment lines. Therefore, there is no definite evidence on the efficacy of single metronomic dosing and firm evidence of metronomic dosing is still missing. There is a need for further confirmation of the usefulness of this approach in clinical practice.

Metronomic chemotherapy for patients with metastatic breast cancer: Review of effectiveness and potential use during pandemics

Metronomic chemotherapy (M-CT) is defined as dose dense administration of chemotherapy at lower doses than maximum tolerated dose but at shorter free intervals, to obtain a near continuous exposure of cancer cells to those potentially effective drugs. M-CT is a useful strategy to obtain response, overcome resistance and reduce side effects, with low costs. This review will focus on the use of M-CT in advanced breast cancer (ABC). Cytostatic and cytotoxic effect on cancer cells, the anti-angiogenic and the immunomodulatory effects are its main mechanisms of actions. Many clinical trials proved the efficacy and tolerability of different monotherapies and combinations of chemotherapeutic agents administered in metronomic doses and frequencies in ABC. M-CT is a reasonable option for second and later lines of chemotherapy in metastatic breast cancer including those with prior anthracycline or taxane exposure, older patients and patients with comorbidities, and even as first-line in certain groups of patients. The acceptable efficacy and low toxicity of oral metronomic chemotherapy makes it a reasonable option during COVID-19 pandemic as well as in the post-COVID era which is projected to last for some time.

Low-dose metronomic chemotherapy as an efficient treatment option in metastatic breast cancer-results of an exploratory case-control study

Purpose

There is growing interest in low-dose metronomic chemotherapy (LDMC) in metastatic breast cancer (MBC). In this retrospective case–control analysis, we compared the efficacy of LDMC and conventional chemotherapy (CCT) in MBC.

Methods

Each LDMC patient receiving oral cyclophosphamide (CTX) (50 mg daily) and methotrexate (MTX) (2.5 mg every other day) was matched with two controls who received CCT. Age, number of chemotherapy lines and metastatic sites as well as hormone receptor (HR) status were considered as matching criteria. Primary endpoint was disease control rate longer than 24 weeks (DCR). Secondary endpoints were progression-free survival (PFS), duration of response (DoR) and subgroup analyses using the matching criteria.

Results

40 cases and 80 controls entered the study. 30.0% patients with LDMC and 22.5% patients with CCT showed DCR (p = 0.380). The median PFS was 12.0 weeks in both groups (p = 0.218) and the median DoR was 31.0 vs. 20.5 weeks (p = 0.383), respectively. Among younger patients, DCR was 40.0% in LDMC vs. 25.0% in the CCT group (p = 0.249). DCR was achieved in 33.3% vs. 26.2% non-heavily pretreated patients (p = 0.568) and in 36.0% vs. 18.0% patients without multiple metastases (p = 0.096), respectively. In the HR-positive group, 30.0% LDMC vs. 28.3% CCT patients showed DCR (p = 1.000). Among triple-negative patients, DCR was achieved in 30.0% LDMC and 5.0% CCT patients (p = 0.095).

Conclusions

We demonstrated a similar efficacy of LDMC compared to CCT in the treatment of MBC. Thus, LDMC may be a valuable treatment option in selected MBC patients.

Highly durable response to capecitabine in patient with metastatic estrogen receptor positive breast cancer: A case report

RATIONALE

In estrogen receptor-positive HER2-negative (ER+HER2-) metastatic breast cancer, chemotherapy should be offered only to patients who develop endocrine resistance or have a rapid disease progression. However, the correct sequence of chemotherapy administration is still debated.

PATIENT CONCERNS

We report the case of a 49-year-old woman with ER+ HER2- metastatic breast cancer who experienced an exceptionally long response to capecitabine administered as second-line therapy following a first-line anthracycline-based chemotherapy.

DIAGNOSES

The patient was diagnosed with ER+ HER2- metastatic breast cancer with massive liver involvement and mediastinal lymph nodes metastasis.

INTERVENTIONS

This patient was treated with capecitabine 1000 mg/mq bid given intermittently for 14 days within a 21-day cycle as a second-line therapy following a rapid progression on letrozole treatment given as a maintenance therapy.

OUTCOMES

Our patient experienced a progression-free survival (PFS) >3 years with an exceptionally good quality of life (QoL).

LESSONS

In ER+HER2- metastatic breast cancer patients, capecitabine monochemotherapy in second line may be associated with a particularly satisfactory PFS and no impact in terms of QoL. Future studies focused on biomarkers with predictive ability may help select patients who represent the best candidates to this treatment.

Metronomic chemotherapy for advanced breast cancer patients in the real world practice: Final results of the VICTOR-6 study

Metronomic chemotherapy (mCHT) refers to the minimum biologically effective dose of a chemotherapy agent given as a continuous dosing regimen, with no prolonged drug-free breaks, that leads to antitumor activity. Aim of the present study is to describe the use of mCHT in a retrospective cohort of metastatic breast cancer (MBC) patients in order to collect data regarding the different types and regimens of drugs employed, their efficacy and safety. Between January 2011 and December 2016, data of 584 metastatic breast cancer patients treated with mCHT were collected. The use of VRL-based regimens increased during the time of observation (2011: 16.8% - 2016: 29.8%), as well as CTX-based ones (2011: 17.1% - 2016: 25.6%), whereas CAPE-based and MTX-based regimens remained stable. In the 1st-line setting, the highest ORR and DCR were observed for VRL-based regimens (single agent: 44% and 88%; combination: 36.7% and 82.4%, respectively). Assuming VRL-single agent as the referee treatment (median PFS: 7.2 months, 95% CI: 5.3-10.3), the longest median PFS were observed in VRL-combination regimens (9.5, 95%CI 88.8-11.3, HR = 0.72) and in CAPE-single agent (10.7, 95%CI 8.3-15.8, HR = 0.70). The VICTOR-6 study provides new data coming from the real-life setting, by adding new information regarding the use of mCHT as an option of treatment for MBC patients.

The NAME trial: a direct comparison of classical oral Navelbine versus Metronomic Navelbine in metastatic breast cancer

Chemotherapy for metastatic breast cancer (MBC) is in general given in cycles of maximum tolerated doses to potentially maximize the therapeutic outcome. However, when compared with targeted therapies for MBC, conventional and dose intensified chemotherapy has caused only modest survival benefits during the recent decades, often compromising the quality of life considerably. Navelbine is an antineoplastic agent that has shown efficacy in the treatment of a variety of cancer types, including breast cancer. Early clinical trials involving both breast cancer and lung cancer patients suggest that metronomic dosing of Navelbine might be at least as effective as classical administration (once weekly, etc.). The NAME trial compares these two strategies of Navelbine administration in MBC patients.

Treating advanced breast cancer with metronomic chemotherapy: what is known, what is new and what is the future?

The prognosis for patients with locally advanced or metastatic breast cancer (mBC) remains poor, with a median survival of 2–4 years. About 10% of newly diagnosed breast cancer patients present with metastatic disease, and 30%–50% of those diagnosed at earlier stages will subsequently progress to mBC. In terms of ongoing management for advanced/metastatic breast cancer after failure of hormonal therapy, there is a high medical need for new treatment options that prolong the interval to the start of intensive cytotoxic therapy, which is often associated with potentially serious side effects and reduced quality of life. Oral chemotherapeutic agents such as capecitabine and vinorelbine have demonstrated efficacy in patients with mBC, with prolonged disease control and good tolerability. Use of oral chemotherapy reduces the time and cost associated with treatment and is often more acceptable to patients than intravenous drug delivery. Metronomic administration of oral chemotherapy is therefore a promising treatment strategy for some patients with mBC and inhibits tumor progression via multiple mechanisms of action. Ongoing clinical trials are investigating metronomic chemotherapy regimens as a strategy to prolong disease control with favorable tolerability. This article provides an overview of metronomic chemotherapy treatment options in mBC, with perspectives on this therapy from a panel of experts.

Metronomic Chemotherapy: A Systematic Review of the Literature and Clinical Experience

Metronomic chemotherapy, continuous and dose-dense administration of chemotherapeutic drugs with lowered doses, is being evaluated for substituting, augmenting, or appending conventional maximum tolerated dose regimens, with preclinical and clinical studies for the past few decades. To date, the principle mechanisms of its action include impeding tumoral angiogenesis and modulation of hosts' immune system, affecting directly tumor cells, their progenitors, and neighboring stromal cells. Its better toxicity profile, lower cost, and easier use are main advantages over conventional therapies. The evidence of metronomic chemotherapy for personalized medicine is growing, starting with unfit elderly patients and also for palliative treatment. The literature reviewed in this article mainly demonstrates that metronomic chemotherapy is advantageous for selected patients and for certain types of malignancies, which make it a promising therapeutic approach for filling in the gaps. More clinical studies are needed to establish a solidified role for metronomic chemotherapy with other treatment models in modern cancer management.

Pan-European Expert Meeting on the Use of Metronomic Chemotherapy in Advanced Breast Cancer Patients: The PENELOPE Project

INTRODUCTION

Metronomic chemotherapy (mCHT) is a treatment regimen in which drugs are administered frequently or continuously and that maintains low, prolonged, and pharmacologically active plasma concentrations of drugs to avoid toxicity associated with traditional chemotherapy regimens, while achieving tumor response. Despite the increasing use of mCHT in patients with metastatic breast cancer (MBC) and the endorsement of mCHT in guidelines, no consensus exists about which patients may substantially benefit from mCHT, which agents can be recommended, and in which treatment setting mCHT is most appropriate.

METHODS

In October 2017, ten international experts in the management of breast cancer convened to develop a report describing the current status of the use of mCHT for the treatment of advanced breast cancer, based not only on current literature but also on their opinion. The Delphi method was used to reach consensus.

RESULTS

A full consensus was reached concerning the acknowledgement that mCHT is not simply a different way of administering chemotherapy but a truly new treatment option. The best-known effect of mCHT is on angiogenesis inhibition, but exciting new data are on the way regarding potential activity on immune system activation. The experts strongly suggest that the ideal patients for mCHT are those with hormone receptor (HR)-positive tumors or those with triple-negative disease. Independently of HR status, mCHT could be an advantageous option for elderly patients, who are often under-treated simply because of their age.

CONCLUSION

Current data support the use of mCHT in selected patients with MBC.

FUNDING

Pierre Fabre.

Randomized phase II study evaluating weekly oral vinorelbine versus weekly paclitaxel in estrogen receptor-positive, HER2-negative patients with advanced breast cancer (NorBreast-231 trial)

BACKGROUND

Single-agent paclitaxel and vinorelbine are recommended treatments for advanced breast cancer (ABC) non-responsive to hormone therapy and without visceral crisis. This phase II trial compared first-line oral vinorelbine versus weekly paclitaxel for ABC.

METHODS

Eligible female patients had measurable locally recurrent/metastatic estrogen receptor-positive HER2-negative breast cancer and had received prior endocrine therapy (any setting) but no chemotherapy for ABC. Patients were stratified by prior taxane and visceral metastases and randomized to either oral vinorelbine 80 mg/m² (first cycle at 60 mg/m², escalated to 80 mg/m² in the absence of grade 3/4 toxicity) or intravenous paclitaxel 80 mg/m² on days 1, 8, and 15 every 3 weeks until disease progression or unacceptable toxicity. The primary endpoint was disease control rate (DCR; confirmed complete or partial response, or stable disease for ≥6 weeks).

RESULTS

The 131 randomized patients had received a median of 2 prior endocrine therapies; >70% had prior (neo)adjuvant chemotherapy and 79% visceral metastases. DCR was 75.8% (95% confidence interval: 63.6-85.5%) with vinorelbine and 75.4% (63.1-85.2%) with paclitaxel. The most common grade 3/4 adverse events were neutropenia (52%), fatigue (11%), and vomiting (5%) with vinorelbine, and neutropenia (17%), dyspnea (6%), hypertension (6%), and peripheral sensory neuropathy (5%) with paclitaxel. Grade 2 alopecia occurred in 2% of vinorelbine-treated and 34% of paclitaxel-treated patients. Neither arm showed relevant global health status changes.

CONCLUSION

Oral vinorelbine and paclitaxel demonstrated similar DCRs (∼75%). Safety profiles differed and, together with administration route and convenience, may influence treatment choice (EudraCT number, 2012-003530-16).

Treatment of advanced breast cancer with a metronomic schedule of oral vinorelbine: what is the opinion of Italian oncologists?

BACKGROUND

The aim of this study was to record the opinions of Italian oncologists about the use of oral vinorelbine administered metronomically in patients with advanced breast cancer.

METHODS

A series of meetings were held throughout Italy, and participants were asked how much they agreed with each of the several statements.

RESULTS

The majority of oncologists agreed that the concept of the minimum biologically effective dose should be used for drugs administered metronomically. Over 50% agreed that metronomic vinorelbine is an option in first-line chemotherapy for patients with advanced breast cancer, including those with a terminal illness and the elderly, as well as in young and fit patients. Just over one-third of experts agreed that a combination of two chemotherapy agents instead of one is not desirable in metastatic breast cancer because of increased toxicity. Most experts agreed that the main aim of a first-line therapy is to control the disease over time and to preserve quality of life.

CONCLUSION

Metronomically administered oral vinorelbine, either as monotherapy or in combination with other drugs, is effective in the long-term treatment of patients with advanced breast cancer. The clinical profiles of patients should be carefully considered to determine the appropriate treatment strategy.

Metronomic Chemotherapy for First-Line Treatment of Metastatic Triple-Negative Breast Cancer: A Phase II Trial

Background

Few data are available on the benefit of metronomic cyclophosphamide, capecitabine, and vinorelbine as first-line therapy in patients with metastatic triple-negative breast cancer.

Methods

This phase II study assessed the safety and efficacy of metronomic oral chemotherapy with vinorelbine 40 mg orally 3 times a week, cyclophosphamide 50 mg daily, and capecitabine 500 mg 3 times a day (VEX regimen) in untreated metastatic triple-negative breast cancer patients. The biopsy of the metastatic site had to be triple-negative, independent of the hormone receptor expression of the primary tumor. The primary endpoint was time to progression (TTP). Secondary endpoints included assessment of safety and clinical benefit (objective response rate plus stable disease rate at ≥24 weeks).

Results

25 patients were included, and 22 were evaluable for both efficacy and toxicities (median age, 66 years). Median TTP was 6.4 months (95% confidence interval 3.6-12.6). The most common grade 1-2 toxicities were nausea, diarrhea, leuko-/neutropenia, and reversible liver enzyme alteration. Grade 3 events included hand and foot syndrome (9%).

Conclusion

The VEX regimen demonstrated activity and was relatively well tolerated when given as first-line therapy in selected metastatic breast cancer patients with triple-negative disease.

Chemotherapeutic agents for the treatment of metastatic breast cancer: An update

Breast cancer is the second greatest cause of death among women worldwide; it comprises a group of heterogeneous diseases that evolves due to uncontrolled cellular growth and differentiation and the loss of normal programmed cell death. There are different molecular sub-types of breast cancer; therefore, various options are selected for treatment of different forms of metastatic breast cancer. However, the use of chemotherapeutic drugs is usually accompanied by deleterious side effects and the development of drug resistance when applied for a longer period. This review offers a classification of these chemotherapeutic agents according to their modes of action and therefore improves the understanding of molecular targets that are affected during treatment. Overall, it will allow the clinician to identify more specific targets to increase the effectiveness of a drug and to reduce general toxicity, resistance and other side effects.

Unfavorable prognostic role of tumor-infiltrating lymphocytes in hormone-receptor positive, HER2 negative metastatic breast cancer treated with metronomic chemotherapy

BACKGROUND

High levels of tumor-infiltrating lymphocytes (TILs) in primary triple negative and HER2-positive breast cancer (BC) have been associated with an improved patients' outcome. The role of TILs in Luminal (hormone receptor positive and HER2 negative) tumors remains to be elucidated. Moreover, the association between TILs and prognosis in the metastatic setting is still unknown.

PATIENTS AND METHODS

We evaluated the relationship between TILs and time to progression (TTP) in metastatic BC patients enrolled in a prospective phase II trial of metronomic chemotherapy, that used cyclophosphamide 50 mg daily, capecitabine 500 mg thrice daily and vinorelbine 40 mg orally three times a week (VEX combination).

RESULTS

Of the 108 ER + BC patients enrolled in the VEX trial, 92 (85%) had sufficient tumor tissue and were assessed for TILs in H&E stained slides. TILs were evaluated in 38 primary BC samples and 54 metastatic sites. High (≥10%) TILs levels were significantly correlated with high Ki-67 labeling index. At multivariable analysis, each 10% increase in TILs strongly predicted a worse TTP (HR: 1.27, p = 0.008). VEX trial patients, categorized by a 3 tiers system (0-4%, 5-9% and >10% TILs) showed significantly different progression free survival curves (p = 0.011).

CONCLUSIONS

High TILs levels are significantly associated with a worse TTP in Luminal metastatic BC patients treated by metronomic chemotherapy. Our data confirm the reliability of TILs as a biomarker in the BC metastatic setting. The putative unfavorable prognostic role of TILs in Luminal BC patients might have clinical utility if validated by further studies.