A multicenter analysis of treatment patterns and clinical outcomes of subsequent therapies after progression on palbociclib in HR+/HER2− metastatic breast cancer

Introduction: Endocrine therapy and cyclin-dependent kinase (CDK) 4/6 inhibitors (CDK4/6i) are standard treatment options for hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2–) metastatic breast cancer (MBC). However, the efficacy of standard subsequent therapies after CDK4/6i-based treatment is unclear. This study aimed to examine physician practice patterns and treatment outcomes of subsequent therapies administered after progression on palbociclib therapy in clinical practice. Methods: The study included 200 patients with HR+/HER2– MBC who underwent subsequent treatments after progressing on palbociclib-based regimens in five Chinese institutions between August 2017 and April 2020. The treatment pattern, progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) were reported. Results: A total of 200 patients were included, of whom 147 (73.5%) and 53 (26.5%) received subsequent chemotherapy and endocrine therapy, respectively. The frequently used monochemotherapy regimens were taxane ( n = 29), capecitabine ( n = 21), and vinorelbine ( n = 17), while the endocrine therapy regimens were chidamide plus exemestane ( n = 16) and everolimus plus exemestane ( n = 9). The overall median PFS (mPFS) was 5.5 months, with no significant difference in mPFS between the chemotherapy and endocrine therapy groups ( p = 0.669). However, among patients not sensitive to prior palbociclib treatment, those administered chemotherapy had significantly longer PFS than those administered endocrine therapy ( p = 0.006). The mPFS with endocrine therapy after first-, second-, and subsequent-line palbociclib was 13.4, 3.1, and 4.1 months, respectively ( p = 0.233); in contrast, the mPFS with chemotherapy was 7.2, 6.5, and 4.9 months after first-, second-, and subsequent-line palbociclib, respectively ( p = 0.364). The median OS was not achieved. The ORR was 10.6% among the 198 patients included in the analysis. Conclusions: Physicians prefer chemotherapy over endocrine therapy for the treatment of patients with HR+/HER2– MBC who develop progression on palbociclib. Sensitivity to previous palbociclib treatment might be one of the indicators for predicting response to subsequent treatment. ClinicalTrials.gov identifier: NCT04517318

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Randomized Phase II Trial of Fulvestrant Plus Everolimus or Placebo in Postmenopausal Women With Hormone Receptor–Positive, Human Epidermal Growth Factor Receptor 2–Negative Metastatic Breast Cancer Resistant to Aromatase Inhibitor Therapy: Results of PrE0102

Journal of Clinical Oncology ◽

10.1200/jco.2017.76.9331 ◽

2018 ◽

Vol 36 (16) ◽

pp. 1556-1563 ◽

Cited By ~ 46

Author(s):

Noah Kornblum ◽

Fengmin Zhao ◽

Judith Manola ◽

Paula Klein ◽

Bhuvaneswari Ramaswamy ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Objective Response ◽

Mammalian Target Of Rapamycin ◽

Growth Factor Receptor ◽

Metastatic Breast ◽

Progression Free Survival ◽

Free Survival ◽

Er Positive ◽

Epidermal Growth

Purpose The mammalian target of rapamycin inhibitor everolimus targets aberrant signaling through the PI3K/AKT/mammalian target of rapamycin pathway, a mechanism of resistance to anti-estrogen therapy in estrogen receptor (ER)–positive breast cancer. We hypothesized that everolimus plus the selective ER downregulator fulvestrant would be more efficacious than fulvestrant alone in ER-positive metastatic breast cancer resistant to aromatase inhibitor (AI) therapy. Patients and Methods This randomized, double-blind, placebo-controlled, phase II study included 131 postmenopausal women with ER-positive, human epidermal growth factor receptor 2–negative, AI-resistant metastatic breast cancer randomly assigned to fulvestrant (500 mg days 1 and 15 of cycle 1, then day 1 of cycles 2 and beyond) plus everolimus or placebo. The study was designed to have 90% power to detect a 70% improvement in median progression-free survival from 5.4 months to 9.2 months. Secondary end points included objective response and clinical benefit rate (response or stable disease for at least 24 weeks). Prophylactic corticosteroid mouth rinses were not used. Results The addition of everolimus to fulvestrant improved the median progression-free survival from 5.1 to 10.3 months (hazard ratio, 0.61 [95% CI, 0.40 to 0.92]; stratified log-rank P = .02), indicating that the primary trial end point was met. Objective response rates were similar (18.2% v 12.3%; P = .47), but the clinical benefit rate was significantly higher in the everolimus arm (63.6% v 41.5%; P = .01). Adverse events of all grades occurred more often in the everolimus arm, including oral mucositis (53% v 12%), fatigue (42% v 22%), rash (38% v 5%), anemia (31% v. 6%), diarrhea (23% v 8%), hyperglycemia (19% v 5%), hypertriglyceridemia (17% v 3%), and pneumonitis (17% v 0%), although grade 3 to 4 events were uncommon. Conclusion Everolimus enhances the efficacy of fulvestrant in AI-resistant, ER-positive metastatic breast cancer.

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Conventional versus cytokinetic polychemotherapy with estrogenic recruitment in metastatic breast cancer: results of a randomized cooperative trial.

Journal of Clinical Oncology ◽

10.1200/jco.1987.5.3.339 ◽

1987 ◽

Vol 5 (3) ◽

pp. 339-347 ◽

Cited By ~ 42

Author(s):

P F Conte ◽

P Pronzato ◽

A Rubagotti ◽

A Alama ◽

D Amadori ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Statistical Significance ◽

Objective Response ◽

Metastatic Breast ◽

Dose Intensity ◽

Progression Free Survival ◽

Free Survival ◽

Significant Prolongation ◽

Significant Difference

Diethylstilbestrol (DES) can induce a recruitment into the proliferative pool of previously resting breast cancer cells in vivo. In order to verify if estrogenic recruitment could result in a larger tumor cell killing by chemotherapy, 117 patients with metastatic breast cancer were randomized to receive CEF (cyclophosphamide, 600 mg/m2; epidoxorubicin, 60 mg/m2; and 5-fluorouracil, 600 mg/m2 on day 1); DES-CEF (cyclophosphamide, 600 mg/m2 on day 1; DES, 1 mg orally on days 5, 6, and 7; and epidoxorubicin, 60 mg/m2, and 5-fluorouracil, 600 mg/m2, on day 8) every 21 days. No significant difference in objective response rates, survival, or progression-free survival was seen between the two regimens. Patients in the DES-CEF arm experienced a higher complete response (CR) rate (24.1% v 16.1%), which reached statistical significance in the case of soft-tissue metastasis (48% v 27.3%; P less than .05) and estrogen receptor-negative tumors (35.7% v 11.1%; P less than .025). Survival and progression-free survival of patients refractory to treatment were not worsened by estrogenic recruitment. In the subset of patients failing after adjuvant polychemotherapy, DES-CEF unexpectedly induced a significantly longer survival (greater than 802 days v 375 days; P = .029) and progression-free survival (239 days v 192 days; P = .041) than CEF. The DES-CEF regimen was more myelotoxic, and 43.3% of the DES-CEF cycles had to be delayed because of leukopenia in comparison with 11.8% of the CEF cycles (P less than .0001). In conclusion, chemotherapy with estrogenic recruitment was able to induce more CRs in certain subsets of patients and a significant prolongation in survival and progression-free survival of patients failing after adjuvant polychemotherapy. These results have been achieved despite a significantly lower dose intensity of chemotherapy.

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Progression-Free Survival and Overall Survival of CDK 4/6 Inhibitors Plus Endocrine Therapy in Metastatic Breast Cancer: A Systematic Review and Meta-Analysis

International Journal of Molecular Sciences ◽

10.3390/ijms21176400 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6400 ◽

Cited By ~ 4

Author(s):

Michela Piezzo ◽

Paolo Chiodini ◽

Maria Riemma ◽

Stefania Cocco ◽

Roberta Caputo ◽

...

Keyword(s):

Breast Cancer ◽

Overall Survival ◽

Metastatic Breast Cancer ◽

Endocrine Therapy ◽

Meta Analysis ◽

Objective Response ◽

Metastatic Breast ◽

Progression Free Survival ◽

Free Survival ◽

Metastatic Sites

The introduction of CDK4/6 inhibitors in combination with endocrine therapy (ET) represents the most relevant advance in the management of hormone receptor (HR) positive, HER2-negative metastatic breast cancer over the last few years. This meta-analysis of randomized controlled trials (RCTs) is aimed to better characterize the efficacy of CDK4/6 inhibitors in some relevant subgroups and to test heterogeneity between different compounds with a particular focus on their ability to improve overall survival (OS). Pooled estimates of hazard ratios (HRs) were computed for progression-free survival (PFS), OS, and objective response rate (ORR) analysis in predefined subgroups to better understand treatment effect concerning specific patients’ characteristics. To estimate the absolute benefit in terms of PFS, pooled survival curves were generated by pooling the data of all trials. A total of eight RCTs were included. Adding a CDK4/6 inhibitor to ET is beneficial in terms of PFS, irrespective of the presence or not of visceral metastases, the number of metastatic sites, and the length of the treatment-free interval (TFI). The addition of CDK4/6 inhibitors produces a significant OS improvement, both in aromatase inhibitor (AI)-sensitive (HR 0.75, 95% CI) and AI-resistant patients (HR 0.77, 95% CI [0.67–0.89]). Pooled data from each single drug show that palbociclib remains the only class member not showing a statistically significant HR for OS (HR 0.83, 95% CI [0.68–1.02]).

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Objective Response to First-Line Treatment as a Predictor of Overall Survival in Metastatic Breast Cancer: A Retrospective Analysis from Two Centers over a 25-Year Period

Breast Care ◽

10.1159/000519729 ◽

2021 ◽

pp. 1-8

Author(s):

Alexios Matikas ◽

Athanasios Kotsakis ◽

Maria Perraki ◽

Dora Hatzidaki ◽

Konstantinos Kalbakis ◽

...

Keyword(s):

Breast Cancer ◽

Overall Survival ◽

Metastatic Breast Cancer ◽

Objective Response ◽

Multivariable Analysis ◽

Metastatic Breast ◽

Progression Free Survival ◽

Subsequent Treatment ◽

First Line ◽

Term Survival

Introduction: The purpose of this study was to study the efficacy of subsequent treatment lines for metastatic breast cancer (MBC), as well as the association between radiologic objective response rate (ORR) and overall survival (OS). Methods: In this retrospective study, consecutive patients treated for MBC in two centers in Greece from January 1, 1992, to December 31, 2016, were identified and clinicopathologic data regarding tumor characteristics and administered treatments were collected. The efficacy per treatment line in terms of ORR, progression-free survival (PFS) and OS, as well as the prognostic value of ORR at first line were investigated. Results: A total of 977 patients with MBC were identified; 950 received any treatment. At first line, ORR was 43.5%, PFS 11.4 months (95% CI 10.4–12.4), and median OS 52.4 months (95% CI 47.7–57.1). Lower ORR and shorter PFS were observed with each subsequent line. Median OS was significantly longer for patients that had an objective response at first line, 61.9 months (95% CI 51.1–69.7) for responders versus 41.3 months (95% CI 44.1–63.3) for nonresponders (p < 0.001). In multivariable analysis, failure to achieve an objective response was an independent predictor of poor survival (hazard ratio 1.70, 95% CI 1.34–2.15, p < 0.001). Conclusion: Late treatment lines for MBC seem to have limited efficacy, while response to first-line therapy is associated with long-term survival. The latter should be considered in the treatment strategy of patients with MBC.

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Post-Progression Treatments after Palbociclib plus Endocrine Therapy in HR+/HER2– Metastatic Breast Cancer Patients: What Is the Better Choice?

Oncology ◽

10.1159/000521252 ◽

2021 ◽

Author(s):

Alessandra Fabi ◽

Mariangela Ciccarese ◽

Sinome Scagnoli ◽

Michelangelo Russillo ◽

Francesco Schettini ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Endocrine Therapy ◽

Metastatic Breast ◽

Progression Free Survival ◽

Subsequent Treatment ◽

Second Line ◽

Breast Cancer Patients ◽

Third Line ◽

Metastatic Sites

Background: To date, a consensus has not yet been reached about the therapy sequence after disease progression (PD) on CDK4/6 inhibitors in patients with HR+/HER2- metastatic breast cancer (MBC). Objectives: The present study assesses, in a real-world setting, the activity of different subsequent therapies in patients who experienced a PD on palbociclib (P) + endocrine therapy (ET), to evaluate the best therapy sequence. Methods: This is a multicenter retrospective observational study. Records of consecutive HR+/HER2- MBC patients from January 2017 to May 2019 were reviewed. The primary endpoint was the evaluation of progression-free survival (PFS) according to subsequent treatment lines after progression on P+ET. Toxicity data were also collected. Results: The outcomes were analyzed in 89 MBC patients that had progressed on previous P+ET: 17 patients were on hormone therapy (HT) and 31 patients on chemotherapy (CT) as second-line treatments; seven patients were on HT and 34 on CT as third-line therapies. PFS of patients treated with HT as second-line therapy is significantly improved when compared with patients treated with CT (p=0.01). Considering third-line settings, the difference in PFS was not statistically different between HT and CT. A better outcome in terms of toxicity is observed among HT patients for both second- and third-line therapies. Conclusions: patients who were progressive on P+ET could still benefit from a subsequent ET. In patients who experienced a good efficacy from prior ET, without visceral metastatic sites, HT seems the most suitable option, when compared to CT, also in terms of safety.

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Abemaciclib, a CDK4 and CDK6 inhibitor for the treatment of metastatic breast cancer

Future Oncology ◽

10.2217/fon-2020-0604 ◽

2020 ◽

Vol 16 (33) ◽

pp. 2763-2778

Author(s):

Miguel Martin ◽

Jose A Garcia-Saenz ◽

Luis Manso ◽

Antonio Llombart ◽

Alejo Cassinello ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Endocrine Therapy ◽

Objective Response ◽

Metastatic Breast ◽

Clinical Trial Data ◽

Progression Free Survival ◽

Standard Of Care ◽

First Line ◽

Free Survival

The addition of CDK4 and 6 inhibitors (abemaciclib, palbociclib or ribociclib) to endocrine therapy, as first-line treatment or following progression after initial endocrine therapy, significantly increased progression-free survival, objective response rates and in some trials overall survival, compared with endocrine therapy alone in HR+ and HER2- breast metastatic breast cancer. These CDK4 and 6 inhibitors are now approved in this context and have become a new standard of care. A hypothesis-generating exploratory analysis suggested that the addition of abemaciclib to endocrine therapy showed the largest effects in subgroups of women with indicators of poor prognosis, although these data require confirmation. This review provides updated clinical trial data for all three drugs in metastatic breast cancer, focusing on abemaciclib, the most recently approved agent.

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Ixabepilone Plus Capecitabine for Metastatic Breast Cancer Progressing After Anthracycline and Taxane Treatment

Journal of Clinical Oncology ◽

10.1200/jco.2007.12.6557 ◽

2007 ◽

Vol 25 (33) ◽

pp. 5210-5217 ◽

Cited By ~ 371

Author(s):

Eva S. Thomas ◽

Henry L. Gomez ◽

Rubi K. Li ◽

Hyun-Cheol Chung ◽

Luis E. Fein ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Treatment Options ◽

Single Agent ◽

Objective Response ◽

Locally Advanced ◽

Metastatic Breast ◽

Progression Free Survival ◽

Phase Iii ◽

Free Survival

PurposeEffective treatment options for patients with metastatic breast cancer resistant to anthracyclines and taxanes are limited. Ixabepilone has single-agent activity in these patients and has demonstrated synergy with capecitabine in this setting. This study was designed to compare ixabepilone plus capecitabine versus capecitabine alone in anthracycline-pretreated or -resistant and taxane-resistant locally advanced or metastatic breast cancer.Patients and MethodsSeven hundred fifty-two patients were randomly assigned to ixabepilone 40 mg/m2intravenously on day 1 of a 21-day cycle plus capecitabine 2,000 mg/m2orally on days 1 through 14 of a 21-day cycle, or capecitabine alone 2,500 mg/m2on the same schedule, in this international phase III study. The primary end point was progression-free survival evaluated by blinded independent review.ResultsIxabepilone plus capecitabine prolonged progression-free survival relative to capecitabine (median, 5.8 v 4.2 months), with a 25% reduction in the estimated risk of disease progression (hazard ratio, 0.75; 95% CI, 0.64 to 0.88; P = .0003). Objective response rate was also increased (35% v 14%; P < .0001). Grade 3/4 treatment-related sensory neuropathy (21% v 0%), fatigue (9% v 3%), and neutropenia (68% v 11%) were more frequent with combination therapy, as was the rate of death as a result of toxicity (3% v 1%, with patients with liver dysfunction [≥ grade 2 liver function tests] at greater risk). Capecitabine-related toxicities were similar for both treatment groups.ConclusionIxabepilone plus capecitabine demonstrates superior efficacy to capecitabine alone in patients with metastatic breast cancer pretreated or resistant to anthracyclines and resistant to taxanes.

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Patterns of treatment and outcome of palbociclib plus endocrine therapy in hormone receptor-positive/HER2 receptor-negative metastatic breast cancer: a real-world multicentre Italian study

Therapeutic Advances in Medical Oncology ◽

10.1177/1758835920987651 ◽

2021 ◽

Vol 13 ◽

pp. 175883592098765

Author(s):

Raffaella Palumbo ◽

Rosalba Torrisi ◽

Federico Sottotetti ◽

Daniele Presti ◽

Anna Rita Gambaro ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Endocrine Therapy ◽

Real World ◽

Hormone Receptor ◽

Metastatic Breast ◽

Progression Free Survival ◽

Her2 Receptor ◽

Treatment Line ◽

Hormone Receptor Positive

Background: The CDK4/6 inhibitor palbociclib combined with endocrine therapy (ET) has proven to prolong progression-free survival (PFS) in women with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2−) metastatic breast cancer (MBC). Few data are available regarding the efficacy of such a regimen outside the clinical trials. Patients and methods: This is a multicentre prospective real-world experience aimed at verifying the outcome of palbociclib plus ET in an unselected population of MBC patients. The primary aim was the clinical benefit rate (CBR); secondary aims were the median PFS, overall survival (OS) and safety. Patients received palbociclib plus letrozole 2.5 mg (cohort A) or fulvestrant 500 mg (cohort B). Results: In total, 191 patients (92 in cohort A, 99 in cohort B) were enrolled and treated, and 182 were evaluable for the analysis. Median age was 62 years (range 47–79); 54% had visceral involvement; 28% of patients had previously performed one treatment line (including chemotherapy and ET), 22.6% two lines and 15.9% three. An overall response rate of 34.6% was observed with 11 (6.0%) complete responses and 52 (28.6%) partial responses. Stable disease was achieved by 78 patients (42.9%) with an overall CBR of 59.8%. At a median follow-up of 24 months (range 6–32), median PFS was 13 months without significant differences between the cohorts. When analysed according to treatment line, PFS values were significantly prolonged when palbociclib-based therapy was administered as first-line treatment (14.0 months), to decrease progressively in second and subsequent lines (11.7 and 6.7 months, respectively). Median OS was 25 months, ranging from 28.0 months in 1st line to 18.0 and 13.0 months in 2nd and subsequent lines, respectively. Conclusions: Our data indicate that palbociclib plus ET is active and safe in HR+/HER2− MBC, also suggesting a better performance of the combinations in earlier treatment lines.

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Observational study of clinical outcomes of eribulin mesylate in metastatic breast cancer after cyclin-dependent kinase 4/6 inhibitor therapy

Future Oncology ◽

10.2217/fon-2019-0537 ◽

2019 ◽

Vol 15 (34) ◽

pp. 3935-3944 ◽

Cited By ~ 4

Author(s):

Sarah S Mougalian ◽

Bruce A Feinberg ◽

Edward Wang ◽

Karenza Alexis ◽

Debanjana Chatterjee ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Clinical Outcomes ◽

Kinase Inhibitor ◽

Objective Response ◽

Metastatic Breast ◽

Progression Free Survival ◽

Cyclin Dependent Kinase ◽

Eribulin Mesylate ◽

Free Survival

Aim: To examine the effectiveness of eribulin mesylate for metastatic breast cancer post cyclin-dependent kinase inhibitor (CDKi) 4/6 therapy. Materials & methods: US community oncologists reviewed charts of patients who had received eriublin from 3 February 2015 to 31 December 2017 after prior CDKi 4/6 therapy and detailed their clinical/treatment history, clinical outcomes (lesion measurements, progression, death) and toxicity. Results: Four patient cohorts were created according to eribulin line of therapy: second line, third line, per US label and fourth line with objective response rates/clinical benefit rates of 42.2%/58.7%, 26.1%/42.3%, 26.7%/54.1% and 17.9%/46.4%, respectively. Median progression-free survival/6-month progression-free survival (79.5% of all patients censored) by cohort was: 9.7 months/77.3%, 10.3 months/71.3%, not reached/70.4% and 4.0 months/0.0%, respectively. Overall occurrence of neutropenia = 23.5%, febrile neutropenia = 1.3%, peripheral neuropathy = 10.1% and diarrhea = 11.1%. Conclusion: Clinical outcome and adverse event rates were similar to those in clinical trials and other observational studies. Longer follow-up is required to confirm these findings.

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PALOMA-3: Phase III Trial of Fulvestrant With or Without Palbociclib in Premenopausal and Postmenopausal Women With Hormone Receptor–Positive, Human Epidermal Growth Factor Receptor 2–Negative Metastatic Breast Cancer That Progressed on Prior Endocrine Therapy—Safety and Efficacy in Asian Patients

Journal of Global Oncology ◽

10.1200/jgo.2016.008318 ◽

2017 ◽

Vol 3 (4) ◽

pp. 289-303 ◽

Cited By ~ 39

Author(s):

Hiroji Iwata ◽

Seock-Ah Im ◽

Norikazu Masuda ◽

Young-Hyuck Im ◽

Kenichi Inoue ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Endocrine Therapy ◽

Growth Factor Receptor ◽

Metastatic Breast ◽

Phase Iii ◽

Asian Patients ◽

Hormone Receptor Positive ◽

Patient Reported ◽

Epidermal Growth

Purpose To assess efficacy and safety of palbociclib plus fulvestrant in Asians with endocrine therapy–resistant metastatic breast cancer. Patients and Methods The Palbociclib Ongoing Trials in the Management of Breast Cancer 3 (PALOMA-3) trial, a double-blind phase III study, included 521 patients with hormone receptor–positive/human epidermal growth factor receptor 2–negative metastatic breast cancer with disease progression on endocrine therapy. Patient-reported outcomes (PROs) were assessed on study treatment and at the end of treatment. Results This preplanned subgroup analysis of the PALOMA-3 study included premenopausal and postmenopausal Asians taking palbociclib plus fulvestrant (n = 71) or placebo plus fulvestrant (n = 31). Palbociclib plus fulvestrant improved progression-free survival (PFS) compared with fulvestrant alone. Median PFS was not reached with palbociclib plus fulvestrant (95% CI, 9.2 months to not reached) but was 5.8 months with placebo plus fulvestrant (95% CI, 3.5 to 9.2 months; hazard ratio, 0.485; 95% CI, 0.270 to 0.869; P = .0065). The most common all-cause grade 3 or 4 adverse events in the palbociclib arm were neutropenia (92%) and leukopenia (29%); febrile neutropenia occurred in 4.1% of patients. Within-patient mean trough concentration comparisons across subgroups indicated similar palbociclib exposure between Asians and non-Asians. Global quality of life was maintained; no statistically significant changes from baseline were observed for patient-reported outcome scores with palbociclib plus fulvestrant. Conclusion This is the first report, to our knowledge, showing that palbociclib plus fulvestrant improves PFS in asian patients. Palbociclib plus fulvestrant was well tolerated in this study.

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