A phase I trial of oral metronomic vinorelbine plus capecitabine in patients with metastatic breast cancer

Metronomic vinorelbine is an excellent and safe treatment for advanced breast cancer: a retrospective, observational study

Advanced breast cancer (ABC) has become a chronic disease. In such a situation, an effective therapy with low toxicities and economically acceptable is needed. Metronomic vinorelbine (mVNR) has been proved to be effective on the control of MBC. The aim of this study is to evaluate the efficacy and safety of mVNR as the salvage therapy for patients with ABC. Oral vinorelbine (VNR) was administered at 70 mg/m2, fractionated on days 1, 3, and 5, for 3 weeks on and 1 week off. Once the mVNR was combined with trastuzumab, or was combined with bevacizumab, the schedule was changed to 2 weeks on and 1 week off. Clinical data of patients with ABC who had received treatment with mVNR and tumor characteristics were collected and analyzed. From Mar. 2013 to Dec, 2020, there were 90 patients with ABC received mVNR. The overall response rate was 53.3% and overall disease control rate (DCR) was 78.9% in this study, including 4 (4.4%) cases reached complete response, 44 (48.9%) cases reached partial response and 23 (25.6%) cases were table disease. The median time to treatment failure (TTF) of the Lumina A patients was 13.3 months, Lumina B patients was 9.1 months, Her-2 enrich patients was 8.9 months, and triple negative breast cancer (TNBC) patients was 5.6 months. Median overall survival time for Lumina A, Lumina B, Her-2 enrich and TNBC were 54.6 months, 53.3 months, 59.5 months and 24.5 months separately. Side effects were minimal and manageable. Metronomic VNR can be an effective treatment for ABC either works as a switch maintenance or salvage therapy. In combination with target therapy or hormonal therapy, mVNR can further improve TTF and DCR with minimal toxicities. Further study should focus on the optimal dosage, schedule and combination regimen.

Safety and efficacy study of oral metronomic vinorelbine combined with trastuzumab (mNH) in HER2-positive metastatic breast cancer: a phase II trial

Purpose

We conducted a single-arm prospective phase II trial to evaluate the efficacy and safety of oral metronomic vinorelbine combined with trastuzumab (mNH) in human epidermal growth factor receptor 2-positive (HER2-positive) metastatic breast cancer (MBC) patients.

Methods

HER2-positive MBC patients received oral vinorelbine 40 mg thrice a week and trastuzumab (loading dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks) until disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoints were objective response rate (ORR), clinical benefit rate (CBR; CR + PR + SD for ≥ 24 weeks). The secondary endpoints were progression-free survival (PFS), tolerability, and overall survival (OS).

Results

Twenty patients with HER2-positive MBC were enrolled, with a median of 1 prior chemotherapy regimens for MBC. Median age was 61.5 years (95% Confidence Interval (CI) 48.6–63.1). Visceral involvements presented in 14 patients (70.0%). ORR was 20.0%, and CBR was 75% with 4 PR (20.0%) and 11 SD (55.0%). The median PFS (mPFS) and median OS (mOS) were 7.4 months (95% CI 3.2–11.5) and 45.8 months (95%CI: not reached), respectively. The mPFS was 17.7 months (95%CI not reached) and 5.8 months (95%CI 5.6–5.9) in mNH as first-line and ≥ second-line therapy (log rank p = 0.03), respectively. The most common grade 1 adverse events (AEs) included nausea (15%), leukopenia (15%), ALT/AST elevation (15%), diarrhea (10%), and peripheral neuropathy (10%). Grade 2 adverse events included leukopenia (5%) and neutropenia (10%). No grade 3/4 AEs were observed.

Conclusions

Oral metronomic vinorelbine combined with trastuzumab is a well-tolerated and effective anti-tumor regimen for HER2-positive MBC.

Metronomic treatment of vinorelbine with oral capecitabine is tolerable in the randomized Phase 2 study XeNa including patients with HER2 non-amplified metastatic breast cancer

BACKGROUND

Metronomic treatment is hypothesized to be less toxic and more effective as compared to standard maximal tolerable dosing treatment in metastatic cancer disease.

MATERIAL AND METHODS

We tested the metronomic treatment principle with vinorelbine in a randomized phase 2 setting combined with standard capecitabine treatment in the XeNa trial with Clinical Trials.gov identifier number: NCT0141771. 120 patients with disseminated HER2 non-amplified breast cancer were included. Randomization was between Arm A: vinorelbine 60 mg/m² day 1 + day 8 in the first cycle followed by 80 mg/m² day 1 + day 8 in the following cycles or Arm B: vinorelbine 50 mg three times a week. Capecitabine 1000 mg/m² twice a day for days 1-14 was administered in both arms.

RESULTS

The treatment was generally well-tolerated. The response rate (RR) was 24% (arm A) versus 29% (arm B) (p = .67). The clinical benefit rate (CBR) 46.8% (arm A) versus 51.7% (arm B) (p = .72). We found a median progression-free survival (PFS) of 7.1 months (95% confidence interval [CI] 3.9-10.3) in arm A and 6.3 months (95% CI 4.1-8.5) in arm B (p = .25) whereas median overall survival (OS) was 23.3 months (95% CI 20.2-26.4) in arm A and 22.3 months (95% CI 14.3-30.3) in arm B (p = .76).

CONCLUSIONS

We confirmed that the combination of vinorelbine and capecitabine was well tolerated. Metronomic treatment can be used with acceptable adverse events (AEs), but we did not find significant difference in the effect compared to the standard treatment.

Phase II clinical trial with metronomic oral vinorelbine and tri-weekly cisplatin as induction therapy, subsequently concomitant with radiotherapy (RT) in patients with locally advanced, unresectable, non-small cell lung cancer (NSCLC). Analysis of survival and value of ctDNA for patient selection

BACKGROUND

Little progress has been achieved in non-small cell lung cancer (NSCLC) patients with unresectable stage III disease and new drug schemes are warranted.

MATERIAL AND METHODS

In this open-label, single-arm, phase II trial 65 treatment-naïve stage III NSCLC deemed surgically unresectable by a multidisciplinary team were treated with 2 cycles of induction cisplatin at 80 mg/m² every 21 days plus metronomic oral vinorelbine at 50 mg/day every Monday, Wednesday and Friday. During the concomitant treatment with thoracic radiotherapy cisplatin was administered in the same manner but oral vinorelbine was reduced to 30 mg/day. The objective was to administer a total radiotherapy dose of 66 Gy in 33 daily fractions of 2 Gy. The primary endpoint was progression-free survival (PFS). Correlation between circulating tumor DNA (ctDNA) levels and survival was also evaluated.

RESULTS

Fifty-five (78.5 %) patients completed treatment. Overall response rate, by RECIST criteria, was 66.2 %. Four (6.2 %) patients had complete response, 39 (60.0 %) partial response and 12 (18.5 %) stable disease. Seven patients (10.8 %) had progressive disease during the induction period. Median follow-up was 29.1 months (m), median PFS was 11.5 m (95 %CI: 9.6-15.4). PFS at 12 m in the intention-to-treat (ITT) population was 47.8 % (95 %CI: 35.1-59.4 %) and median OS was 35.6 m (95 %CI: 24.4-46.8). Grade ≥3 treatment-related adverse events occurred in 14 (21.5 %) patients during induction and in 13 (24.5 %) patients during concomitant treatment with esophagitis occurring in 3% and pneumonitis in 1.5 % of the patients. Patients with undetectable ctDNA after 3 m follow-up had median PFS and OS of 18.1 m (95 %CI: 8.8-NR) and not reached (NR) (95 %CI: 11.3-NR), respectively, compared with 8.0 m (95 %CI: 2.7-NR) and 24.7 m (95 %CI: 5.7-NR) for patients who remained ctDNA positive at that time point.

CONCLUSIONS

Metronomic oral vinorelbine and cisplatin obtains similar efficacy results with significantly lower toxicity than the same chemotherapy at standard doses. ctDNA can identify populations with particularly good prognosis.

Treatment of Metastatic or High-Risk Solid Cancer Patients by Targeting the Immune System and/or Tumor Burden: Six Cases Reports

This article summarizes the histories of six patients with different solid tumors treated with a new strategy based on tumor burden reduction and immune evasion as potential targets. All six patients were at a high risk of relapse and were likely to have a minimal residual disease following conventional therapy: biochemical recurrence (BCR) following radical prostatectomy (RP) (two prostate cancers patients), removal of distant metastases (one colorectal and one breast cancer), and complete response (CR) of distant metastases to conventional therapy (one breast cancer and one esophageal–gastric junction cancer). Four of the patients, two after RP and BCR, one after removal of a single pulmonary metastasis from breast cancer, and one after CR to chemotherapy of peritoneal metastases and ascites from an esophageal–gastric junction primary cancer, regularly received cycles of a new drug schedule with the aim of inhibiting immune suppression (IT). In these four patients, preliminary laboratory tests of peripheral blood suggested an interleukin (IL)-2/IL-12 mediated stimulation of cellular immune response with a concomitant decrease in vascular endothelial growth factor (VEGF) immune suppression. The fifth case was a breast cancer patient with distant metastases in CR, while receiving beta-interferon and interleukin-2 in addition to conventional hormone therapy. To date, all five patients are alive and doing well and they have been unexpectedly disease-free for 201 and 78 months following BCR, 28 months following the removal of a single pulmonary metastases, 32 months following CR to chemotherapy of peritoneal metastases and ascites, and 140 months following diagnosis of multiple bone metastases, respectively. The sixth patient, who had colorectal cancer and multiple synchronous liver metastases and underwent nine surgical interventions for metastatic disease, although not disease-free, is doing well 98 months after primary surgery. Our six cases reports can be interpreted with the hypothesis that immune manipulation and/or a concomitant low tumor burden favored their clinical outcome.

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.

Is there still a place for vinorelbine in advanced metastatic castration resistant prostate cancer?

The aim of this paper was to evaluate the activity and tolerability of oral vinorelbine in patients with advanced castration resistant prostate cancer (CRPC) who progressed after a minimum of three lines including: abiraterone acetate, docetaxel, cabazitaxel, and enzalutamide.Treatment consisted of weekly oral vinorelbine 60 mg/m. Chemotherapy was administered until disease progression or unacceptable toxicity.Twenty-six patients received vinorelbine: their median age was 74 years (range 58-84 years). Twenty-four (92.3%) patients had bone metastases. A decrease in PSA levels ≥50% was observed in 2 patients (7.7%). Among the subjects who were symptomatic at baseline, pain was reduced in 3 patients (13.6%) with a significant decrease in analgesic use. Median progression-free survival was 9 weeks (95% CI: 7 to 11) and median overall survival was 17 weeks (95% CI: 12 to 22). Treatment was well tolerated, and no grade 4 toxicities were observed.Our findings do not suggest the use of oral vinorelbine on a weekly schedule, in CRPC heavily pre-treated.

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.

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.

Metronomic chemotherapy in metastatic colorectal cancer

Overall survival and quality of life of patients with metastatic colorectal cancer (mCRC) have improved due to the development of standard systemic treatment. However, many patients are still suffering from the eventual progression of cancer, treatment-related toxicities, and the economic burden of new drugs. Salvage or maintenance therapy, which consistently controls or stabilizes tumor progression without debilitating quality of life, is required. Recently, metronomic capecitabine maintenance therapy after disease control using conventional chemotherapy with maximal tolerated doses has demonstrated beneficial results in a phase III trial. Metronomic chemotherapy has been known to control tumors through antiangiogenesis and immunomodulation as well as a direct effect on tumor-initiating cells. It has the characteristics of being minimally toxic, inexpensive, and durable for maintaining disease stabilization. Therefore, patients with mCRC, who tend to be elderly and frail and have been previously treated, might be suitable for metronomic therapeutic strategies. Furthermore, antiangiogenic therapy has been an important component in treating mCRC, but the schedules and doses of metronomic chemotherapy have not yet been established. Here we review translational and clinical research on metronomic chemotherapy in colorectal cancer (CRC).

Metronomic chemotherapy: A potent macerator of cancer by inducing angiogenesis suppression and antitumor immune activation

Metronomic chemotherapy is a low dosing treatment strategy that attracts growing scientific and clinical interest. It refers to dense and uninterrupted administration of low doses of chemotherapeutic agents (without prolonged drug free intervals) over extended periods of time. Cancer chemotherapy is conventionally given in cycles of maximum tolerated doses (MTD) with the aim of inducing maximum cancer cell apoptosis. In contrast, the primary target of metronomic chemotherapy is the tumor's neovasculature. This is relevant to the emerging concept that tumors exist in a complex microenvironment of cancer cells, stromal cells and supporting vessels. In addition to its anti-angiogenetic properties, metronomic chemotherapy halts tumor growth by activating anti-tumor immunity, thus decreasing the acquired resistance to conventional chemotherapy. Herein, we present a review of the literature that provides a scientific basis for the merits of chemotherapy when administered on a metronomic schedule.

Metronomic Chemotherapy for Metastatic Breast Cancer - a Systematic Review of the Literature

Conventional chemotherapy is generally administered in high doses followed by a treatment-free period to give the body needful time to recover. This "maximum tolerated dose" approach results in high response rates. However, long periods between therapy cycles can lead to development of resistance mechanisms and consequently disease progression. One of the most interesting alternative strategies is metronomic chemotherapy. This concept relies on the continuous administration of chemotherapy at low doses and aims at targeting endothelial cells in the tumor bed as well. Recently, metronomic chemotherapy has been incorporated into the recommendations issued by the German AGO expert panel (www.ago-online.de). A systematic review of PubMed/Medline, ClinicalTrials.gov, the European Clinical Trials Database (EudraCT) and the Cochrane Database was conducted. In the present review, we discuss the current evidence on metronomic chemotherapy in metastatic breast cancer.

Phase I Study of Oral Vinorelbine in Combination with Erlotinib in Advanced Non-Small Cell Lung Cancer (NSCLC) Using Two Different Schedules

Purpose

This study aimed to evaluate the safety, tolerability and pharmacokinetics of the combination of oral vinorelbine with erlotinib using the conventional (CSV) and metronomic (MSV) dosing schedules in patients with advanced non-small cell lung cancer (NSCLC).

Methods

This was an open-label, multiple dose-escalation phase I study. An alternating 3+3 phase I design was employed to allow each schedule to enroll three patients sequentially at each dose level. Thirty patients with Stage IIIB/IV NSCLC were treated with escalating doses of oral vinorelbine starting at 40 mg/m² on day 1 and 8 in the CSV group (N = 16) and at 100 mg/week in the MSV group (N = 14). Erlotinib was administered orally daily.

Results

The maximum tolerated dose was vinorelbine 80 mg/m² with erlotinib 100 mg in the CSV group and vinorelbine 120 mg/week with erlotinib 100 mg in the MSV group. Grade 3/4 toxicities included neutropenia (N = 2; 13%) and hyponatremia (N = 1; 6%) in the CSV group, and neutropenia (N = 5; 36%) in the MSV group. Objective response was achieved in 38% and 29% in the CSV and MSV groups respectively. Vinorelbine co-administration did not significantly affect the pharmacokinetics of erlotinib and OSI-420 after initial dose. However, at steady-state, significantly higher C_max, higher C_min and lower CL/F of erlotinib were observed with increasing dose levels of vinorelbine in the CSV group. Significantly higher steady-state C_min, C_avg and AUC_ss of erlotinib were observed with increasing dose levels of vinorelbine in the MSV group.

Conclusions

Combination of oral vinorelbine with erlotinib is feasible and tolerable in both the CSV and MSV groups.

Trial Registration

ClinicalTrials.gov NCT00702182

Dose-Dense Chemotherapy in Metastatic Breast Cancer: Shortening the Time Interval for a Better Therapeutic Index

Despite the advancement of targeted therapies in metastatic breast cancer, chemotherapy is still of pivotal importance. The concept of dose density is known to increase the efficacy of chemotherapy. In metastatic disease, preservation of the quality of life is equally important. Because of this, weekly regimens are a cornerstone in metastatic disease. Taxanes like paclitaxel or nab-paclitaxel as well as antracyclines are often used in palliative treatment. Further advances to increase dose density have led to the concept of daily metronomic schedules with oral chemotherapeutic drugs like cyclophosphamide, capecitabine, or vinorelbine. Metronomic chemotherapy affects tumor angiogenesis and also weakens immunosuppressive regulatory T cells, promoting better control of tumor progression. Weekly or daily dose-dense regimens are a reasonable compromise between efficacy and toxicity to improve the therapeutic index. This is most important for the treatment of chronic disease where palliation and preservation of quality of life are vital.

Metronomic oral vinorelbine in advanced breast cancer and non-small-cell lung cancer: current status and future development

Metronomic chemotherapy (mCT), a frequent administration of low-dose chemotherapy, allows prolonged treatment duration and minimizes the toxicity of standard-dose chemotherapy. mCT has multiple actions against cancer cells including inhibition of angiogenesis and modulation of the immune system. A number of studies lend support to the clinical efficacy of mCT in advanced breast cancer and non-small-cell lung cancer. However, further evidence is necessary to describe the optimal use of mCT and to identify suitable patients. Oral vinorelbine has emerged as a promising metronomic treatment in patients with metastatic breast cancer and non-small-cell lung cancer and is the only orally available microtubule-targeting agent. This paper reviews current evidence on metronomic oral vinorelbine, discusses its management and defines a suitable patient profile on the basis of a workshop of Italian experts.

On and off Metronomic Oral Vinorelbine in Elderly Women with Advanced Breast Cancer

Background

Elderly patients with metastatic breast cancer (MBC) have more problems receiving chemotherapy than younger patients, especially with the presence of multiple comorbidities, adverse drug events and functional decline. Low-dose oral administration of cytotoxic agents such as vinorelbine, a semisynthetic vinca alkaloid that interferes with microtubule assembly, leading to arrest of cell division, is usually effective and well tolerated.

Methods

From February 2010 to February 2014, 32 patients with MBC, median age 76 years (range 69-83) were treated with oral vinorelbine 30 mg (total dose), one day on and one day off, until disease progression or unacceptable toxicity levels were reported. Toxicity, quality of life and clinical benefit were evaluated. Matched t-tests were conducted to discern whether quality-of-life indicator (p<0.05 was considered significant) differed before and 6 months after treatment. Statistical analysis was performed using Graph Pad Prism 5.0 (GraphPad Software Inc., San Diego, CA, USA).

Results

No grade 3 and 4 adverse events were reported. A clinical benefit of 50% was found in our cohort. On and off metronomic vinorelbine oral administration resulted in good tolerability and safe profile in our selected elderly population, and improved patient adherence to therapy.

Conclusions

The present study demonstrated that metronomic vinorelbine might be a potential treatment in elderly patients by reducing adverse effects and increasing quality of life, setting the stage for future extensive clinical trials.

Metronomics chemotherapy: time for computational decision support

Over the last decade, metronomic chemotherapy has been increasingly considered as an attractive strategy for treating cancer in a variety of settings. Beside pharmaco-economic considerations making metronomics a unique opportunity in low- or middle-income countries, revisiting dosing schedules using continuous low doses of cytotoxics should theoretically permit to reduce the incidence of treatment-related toxicities, while offering unexpected novel mechanisms of actions such as antiangiogenic or immuno-stimulating properties. Consequently, a number of clinical trials sought to evaluate to what extent switching to metronomic schedules could actually impact indeed on the efficacy/toxicity balance of a variety of anticancer drugs in both adults and pediatric oncology. Vinorelbine is a vinca-alcaloïd that remains the backbone of several regimens to treat patients with metastatic breast cancer or non-small cell lung cancer. Additionally, vinorelbine is widely used to treat a variety of solid tumors in children such as rhabdomyosarcomas and acute leukemia. The recent approval of an oral formulation of vinorelbine has open the way to developing alternative metronomic schedules with this drug. Consequently, a number of clinical trials investigating on metronomic vinorelbine have been performed over the last few years, with seemingly inconsistent results to date. Of note, all the studies published thus far were based upon empirical determination of the metronomic schedule, both in terms of doses, drug-free intervals and repartition of the administrations throughout time. Because the very concept of «low, repeated doses with little or no drug-free interval» covers numerous possible combinations, determining the optimal protocol using traditional under-powered empirical design looks like an unreachable goal. In this context, mathematical modeling offers invaluable in silico tools to help determining the optimal metronomic schedule among a variety of possibilities. This review covers the latest clinical trials investigating on metronomic vinorelbine and proposes alternative strategies for developing computational decision support to make metronomics a scientific-grounded strategy, rather than an empirical practice at the bedside. In particular, mathematical simulations using an original pharmacokinetics/pharmacodynamics constraint models provide clues for exploring new paths in the way metronomic vinorelbine could be scheduled in patients with lung cancer.

Metronomic therapy and breast cancer: a systematic review

Metronomic therapy (MT) refers to repetitive, low doses of chemotherapy drugs. MT exerts an effect not only on tumour cells, but also on their microenvironment. In particular, the low-dose schedule compromises the repairing process of endothelial cells, leading to an anti-angiogenic effect. In addition to the anti-angiogenic effect, MT could have an immunological action through the restoration of the anticancer effect of the immune system and induction of tumour dormancy. Consequently the association of targeted therapy with anti-angiogenic properties or specific immunologic drugs could enhance the efficacy of MT. During the past 15 years, several studies have been published evaluating the metronomic strategy in breast cancer. We conducted a systematic review of the results of phase I, II and III studies testing MT in breast cancer patients. The analyses included the efficacy and toxicity data of MT, and the future development of this strategy in breast cancer are also discussed. The systematic review presented here suggests that MT is a treatment option for breast cancer patients, has a low toxicity profile, efficacy in most patients and has potentially significant cost-effective advantages for public health.

Metronomics: towards personalized chemotherapy?

Since its inception in 2000, metronomic chemotherapy has undergone major advances as an antiangiogenic therapy. The discovery of the pro-immune properties of chemotherapy and its direct effects on cancer cells has established the intrinsic multitargeted nature of this therapeutic approach. The past 10 years have seen a marked rise in clinical trials of metronomic chemotherapy, and it is increasingly combined in the clinic with conventional treatments, such as maximum-tolerated dose chemotherapy and radiotherapy, as well as with novel therapeutic strategies, such as drug repositioning, targeted agents and immunotherapy. We review the latest advances in understanding the complex mechanisms of action of metronomic chemotherapy, and the recently identified factors associated with disease resistance. We comprehensively discuss the latest clinical data obtained from studies performed in both adult and paediatric populations, and highlight ongoing clinical trials. In this Review, we foresee the future developments of metronomic chemotherapy and specifically its potential role in the era of personalized medicine.

Efficacy and Safety of the All-Oral Schedule of Metronomic Vinorelbine and Capecitabine in Locally Advanced or Metastatic Breast Cancer Patients: The Phase I-II VICTOR-1 Study

Background. Vinorelbine (VRB) and capecitabine (CAPE) are demonstrated to be active in pretreated metastatic breast cancer patients. Different studies have demonstrated that the metronomic treatment is active with an acceptable toxicity profile. We designed a Phases I-II study to define the MTD of oral metronomic, VRB, and CAPE. Patients and Methods. Phase I: fixed dose of CAPE was 500 mg thrice a day, continuously. Level I of VRB was 20 mg/tot thrice a week for 3 weeks (1 cycle). Subsequent levels were 30 mg/tot and 40 mg/tot (Level III), respectively, if no Grades 3-4 toxicity were observed in the previous level. Phase II: further 32 patients received the MTD of VRB plus CAPE for a total of 187 cycles to confirm toxicity profile. Results. 12 patients were enrolled in Phase I and 22 in Phase II. Phase I: the MTD of VRB was 40 mg. Phase II: 187 cycles were delivered, observing 5.9% of Grades 3-4 toxicity. 31 patients are evaluable for efficacy, obtaining a clinical benefit rate of 58.1%. Conclusion. MTD of VRB with fixed dose of CAPE was 40 mg thrice a week and was the recommended dose for the ongoing Phase II multicenter study.