Ribociclib with letrozole vs letrozole alone in elderly patients with hormone receptor-positive, HER2-negative breast cancer in the randomized MONALEESA-2 trial

Elderly patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with CDK4/6 inhibitors in a multicentre cohort

INTRODUCTION

Cyclin-dependent kinases 4/6 inhibitors (CDK 4/6i) combined with endocrine therapy have become the gold standard in hormone receptor-positive (HR +) HER2-negative (HER2-) metastatic breast cancer (MBC). However, there is a significant lack of data regarding the efficacy and safety of these treatments in elderly patients. We present the results of a real-world data (RWD) cohort stratified by age at treatment initiation (≥ 70 years compared to patients < 70 years).

METHODS

Clinico-pathological data of HR + HER2- MBC patients who were candidates for CDK4/6i therapy between January 2017 and December 2020 at the Institut Català d'Oncologia (Spain) were retrospectively collected. The primary goal was to assess Progression-Free Survival (PFS), Overall Survival (OS), and safety outcomes within this patient population.

RESULTS

A total of 274 patients with MBC who received CDK4/6i treatment were included in the study. Among them, 84 patients (30.8%) were aged ≥ 70 years, with a mean age of 75, while 190 patients (69.2%) were under the age of 70, with a mean age of 55.7 years. The most frequently observed grade 3-4 toxicity was neutropenia, with similar rates in both the < 70 group (43.9%) and the ≥ 70 group (47.9%) (p = 0.728). The median Progression-Free Survival (mPFS) for the first-line CDK4/6i treatment was 22 months (95% CI, 15.4-39.8) in the < 70 group and 20.8 months (95% CI 11.2-NR) in the ≥ 70 group (p = 0.67). Similarly, the median PFS for the second-line CDK4/6i treatment was 10.4 months (95% CI, 7.4-15.1) and 7.1 months (95% CI 4.4-21.3) (p = 0.79), respectively. Median overall survival (mOS) was not reached either for the first- and second-line treatment.

CONCLUSIONS

Our RWD suggests that elderly patients, when compared to those under 70, experience similar survival outcomes and exhibit comparable tolerance for CDK4/6i therapy.

Should the Use of Acid Reducing Agents in Conjunction with Ribociclib be Avoided? An Integrated QbD Approach for Assessment of pH-Mediated Interaction

The objective of the study was to evaluate the possible pH-dependent interaction of ribociclib succinate with acid-reducing agents, which are concomitantly administered as supportive care medicines in cancer. Quality by Design-based analytical method development for a weakly basic drug ribociclib succinate supposedly having the characteristic ability of pH-dependent solubility was carried out for analyzing micro-dissolution experiment samples in biorelevant media to study pH-dependent interaction. An accurate and robust analytical method was developed using a three-level three-factorial box-behnken design for quantification of ribociclib succinate in micro-dissolution samples by the implementation of the Analytical Quality by Design approach. Here, pH of aqueous mobile phase and flow rate proved to be critical process parameters. The gastric compartment solubility was found to be 814.05 μg/mL, which dropped down to 494.71 μg/mL after a pH shift from pH 1.2-6.5. In the intestinal compartment, initial solubility was 717.58 μg/mL, which reduced to 463.20 μg/mL after a pH shift from 6.5 to 6.8. Concluded results state that pH shift does not impact the solubility or the absorption of the drug to a significant extent in the presence of acid-reducing agents. However, the study would prove to be a practical approach for examination of the behavior of the drugs at the initial stages.

Establishment and Validation of Novel Prognostic Subtypes in Hepatocellular Carcinoma Based on Bile Acid Metabolism Gene Signatures Using Bulk and Single-Cell RNA-Seq Data

Hepatocellular carcinoma (HCC) is a highly detrimental cancer type and has limited therapeutic options, posing significant threats to human health. The development of HCC has been associated with a disorder in bile acid (BA) metabolism. In this study, we employed an integrative approach, combining various datasets and omics analyses, to comprehensively characterize the tumor microenvironment in HCC based on genes related to BA metabolism. Our analysis resulted in the classification of HCC samples into four subtypes (C1, C2a, C2b, and C3). Notably, subtype C2a, characterized by the highest bile acid metabolism score (BAMS), exhibited the highest survival probability. This subtype also demonstrated increased immune cell infiltration, lower cell cycle scores, reduced AFP levels, and a lower risk of metastasis compared to subtypes C1 and C3. Subtype C1 displayed poorer survival probability and elevated cell cycle scores. Importantly, the identified subtypes based on BAMS showed potential relevance to the gene expression of drug targets in currently approved drugs and those under clinical research. Genes encoding VEGFR (FLT4 and KDR) and MET were elevated in C2, while genes such as TGFBR1, TGFB1, ADORA3, SRC, BRAF, RET, FLT3, KIT, PDGFRA, and PDGFRB were elevated in C1. Additionally, FGFR2 and FGFR3, along with immune target genes including PDCD1 and CTLA4, were higher in C3. This suggests that subtypes C1, C2, and C3 might represent distinct potential candidates for TGFB1 inhibitors, VEGFR inhibitors, and immune checkpoint blockade treatments, respectively. Significantly, both bulk and single-cell transcriptome analyses unveiled a negative correlation between BA metabolism and cell cycle-related pathways. In vitro experiments further confirmed that the treatment of HCC cell lines with BA receptor agonist ursodeoxycholic acid led to the downregulation of the expression of cell cycle-related genes. Our findings suggest a plausible involvement of BA metabolism in liver carcinogenesis, potentially mediated through the regulation of tumor cell cycles and the immune microenvironment. This preliminary understanding lays the groundwork for future investigations to validate and elucidate the specific mechanisms underlying this potential association. Furthermore, this study provides a novel foundation for future precise molecular typing and the design of systemic clinical trials for HCC therapy.

Key Considerations for the Treatment of Advanced Breast Cancer in Older Adults: An Expert Consensus of the Canadian Treatment Landscape

The prevalence of breast cancer amongst older adults in Canada is increasing. This patient population faces unique challenges in the management of breast cancer, as older adults often have distinct biological, psychosocial, and treatment-related considerations. This paper presents an expert consensus of the Canadian treatment landscape, focusing on key considerations for optimizing selection of systemic therapy for advanced breast cancer in older adults. This paper aims to provide evidence-based recommendations and practical guidance for healthcare professionals involved in the care of older adults with breast cancer. By recognizing and addressing the specific needs of older adults, healthcare providers can optimize treatment outcomes and improve the overall quality of care for this population.

PROPSEA, safety evaluation of palbociclib and ribociclib in older patients with breast cancer: A prospective real-world TOG study

INTRODUCTION

In this study, the toxicities and management of palbociclib and ribociclib in older patients (≥65 years) with metastatic breast cancer patients were investigated.

MATERIALS AND METHODS

Among older patients receiving palbociclib and ribociclib, Geriatric 8 (G8) and Groningen Frailty Index were used to evaluate frailty status. Dose modifications, drug withdrawal and other serious adverse events (SAEs) were recorded and analyzed according to baseline patient characteristics.

RESULTS

A total of 160 patients from 28 centers in Turkey were included (palbociclib = 76, ribociclib = 84). Forty-three patients were ≥ 75 years of age. The most common cause of first dose modification was neutropenia for both drugs (97% palbociclib, 69% ribociclib). Liver function tests elevation (10%) and renal function impairment (6%) were also causes for ribociclib dose modification. Drug withdrawal rate was 3.9% for palbociclib and 6% for ribociclib. SAEs were seen in 11.8% of those taking palbociclib and 15.5% of those on riboclib. An ECOG performance status of ≥2 and being older than 75 years were associated with dose reductions. Severe neutropenia was more common in patients with non-bone-only metastatic disease, those receiving treatment third-line therapy or higher, coexistance of non-neutropenic hematological side effects (for ribociclib). Neutropenia was less common among patients with obesity.

DISCUSSION

Our results show that it can be reasonable to start palbociclib and ribociclib at reduced dose in patients aged ≥75 years and/or with an ECOG performance status ≥2.

The role of CDK4/6 inhibitors in older and younger patients with breast cancer: A systematic review and meta-analysis

INTRODUCTION

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors have an extremely important impact on the treatment of hormone-sensitive breast cancer (BC) and have radically changed the first-line treatment for metastatic disease with increased rates of treatment response, overall survival (OS), and progression-free survival (PFS). We performed a pooled analysis of randomized trials to validate or refute the hypothesis that there is a significant survival benefit of adding anti-CDK4/6 inhibitors to standard endocrine therapy (ET) in older patients with advanced BC.

METHODS

We selected only English-language phase II/III randomized controlled trials that compared ET alone with ET with anti-CDK4/6 inhibitors in the treatment of advanced BC, with subgroups reporting the outcomes of elderly patients (usually at least 65 years). The primary endpoint was OS.

RESULTS

The review process led to the inclusion of 12 articles and two meeting abstracts, including a total of 10 trials. The addition of CDK4/6 inhibitors to ET (letrozole or fulvestrant) significantly reduced mortality risk by 20% in younger patients (fixed-effect model; HR 0.80; 95% CI 0.72-0.9; p < 0.01) and 21% in older BC patients (HR 0.79; 95% CI 0.69-0.91; p < 0.01). No OS data were available for patients ≥70 years.

CONCLUSION

This large, pooled analysis is the first to demonstrate that CDK4/6 inhibitors confer OS and PFS benefits in elderly patients (those aged ≥65 years) with advanced ER + BC and to indicate that it should be discussed with and offered to all patients after geriatric assessment and according to the toxicity profile.

The Treatment Landscape of Elderly Patients with Hormone Receptor-Positive Her2 Negative Advanced Breast Cancer: Current Perspectives and Future Directions

Breast cancer (BC) in elderly women is an increasing health issue due to demographic changes. BC tends to present later and may receive less than standard treatment options. More often, BC in elderly patients is endocrine-positive (HR+). The treatment of elderly patients with metastatic BC (mBC) represents a therapeutic challenge. In recent years, the treatment landscape of patients that are HR+/Her2-negative has changed due to the introduction in clinical practice of new targeted drugs, which have improved patient outcomes. Elderly patients are a small percentage of all patients enrolled in clinical trials and, to date, there are no standardized guidelines that define the best treatment option for this patient population. This can lead to undertreatment or overtreatment, impacting patient morbidity and mortality. Geriatric Assessment tools to tailor the treatment in elderly patients are underused because they are long and difficult to apply in a busy routine clinical practice. For all these reasons, there is an urgent need to produce data about the best treatment for elderly patients with HR+ mBC. Herein, we report data from randomized clinical trials and real-world evidence on the therapeutic options for HR+ Her2-negative mBC elderly patients and explore future treatment directions.

An experimental study: the effect of S. boulardii on abemaciclibinduced diarrhea

BACKGROUND

In our study, we aimed to investigate the protective effects of Saccharomyces boulardii on abemaciclib-induced diarrhea model, which is a commonly used drug in breast cancer.

METHODS

Thirty rats were divided into 3 groups as control (Group 1), abemaciclib (Group 2), and abemaciclib + Saccharomyces boulardii (Group 3) groups. The clinical status, body weight, and defecation status were monitored daily. At the end of the 15-day experiment period, the rats were killed with high-dose anesthesia and the resected small intestine segments were evaluated histopathologically. Lesions were classified according to thickening of the villus, inflammation and edema of mucosa and intraepithelial leukocyte accumulation. Then, mean values of both crypt depths and villi thicknesses were calculated for each rat. Normal distribution assumption was controlled with the Shapiro-Wilk test. One-way analysis of variance for normally distributed variables in the comparisons of more than two independent groups and Kruskal-Wallis test for nonnormally distributed variables were used. The significance value was accepted as 0.05.

RESULTS

: There was one death in Group 3, but none in the others. There were no findings of mucositis in Group I. There was mild diarrhea and weight loss in only one rat in Group 1. For the comparison of the severity of diarrhea (72.5%/39%) and weight loss (72.5%/45%), a decrease was found in Group 3 according to Group 2 (p < 0.01). Histopathological findings such as edema, inflammation, and intraepithelial leukocyte accumulation also showed a decrease in Group 3 compared to Group 2 (p < 0.01).

DISCUSSION

Saccharomyces boulardii should be considered as a treatment option in abaemaciclib (chemotherapy)-induced diarrhea. Further comparative studies and in vivo human randomized controlled studies can be conducted in the future.

Patients with severe coronavirus disease 2019 have high frequency of factor 5 Leiden and prothrombin gene mutations

We investigated the frequency of factor 5 Leiden (FVL) and prothrombin gene (PTG) mutations in patients with severe coronavirus disease 2019 (COVID-19). Our primary aim is to reveal whether these mutations are associated with severity of disease and mortality. A total of 249 patients were included in this cross-sectional study. Severe COVID-19 cases (with oxygen saturation of less than 90 mmHg and who received ventilation support invasively or noninvasively) were included. FVL and PTG mutations were identified by real time- PCR technique. Frequency of mutations for FVL was 11.7%, whereas for PTG was 3.5%. The frequency of FVL and PTG's mutations in our patient group was found to be significantly higher than the normal population ( P  < 0.0001, 0.004, respectively). There was no difference in the frequency of mutations of FVL and PTG between the patients ventilated - invasively and noninvasively. There was also no difference in D-dimer, ferritin, fibrinogen, ex status, and entubational status between the groups of FVL and PTG mutated and wild-type. To the best of our knowledge, it is the first time that we have examined the frequencies of FVL and PGM's mutations in severe COVID-19 disease on such a large scale. The frequencies of both mutations in severe COVID-19 patients were higher than in the healthy population. We believe that studies prospectively designed, including asymptomatic and mild COVID-19 patients, will provide more comprehensive information on the subject.

The 5-Year Disease-Free Survival of Third Generation Aromatase Inhibitor for Postmenopausal Women with HR-Positive HER2-Negative Non-Metastatic Breast Cancer

Background: Several studies showed the superiority of aromatase inhibitor (AI) as first-line therapy for patients with hormone-receptor (HR)-positive breast cancer (BC). For the clinician, studies in the real world are warranted to determine treatment based on the efficacy of each drug. We compared a 5-y disease-free survival (DFS) of each AI in terms of survival benefit. Materials and Methods: We evaluated 450 medical records of postmenopausal women who were diagnosed with HR-positive HER2-negative BC (stage I - III) at Dr. Sardjito General Hospital from January to December 2019. All patients had undergone surgery and chemotherapy or radiation therapy. Moreover, study participants received anastrozole, letrozole, or exemestane for at least one year. Kaplan Meier estimation survival curve was used to analyze the survival rate. Result: Of 79 patients meeting inclusion criteria, there were 21.52% distant metastases documented. Time to disease progression of anastrozole, letrozole, and exemestane was 49 months, 58 months, and 53 months, respectively. Letrozole was found better than anastrozole (hazard ratio (HR)=4.342, 95% CI 0.95-19.95; p=0.038). Letrozole versus exemestane (HR=2.757, 95% CI 0.53-14.33; p=0,206) and anastrozole versus exemestane (HR=1.652, 95% CI 0.56-4.84; p=0.351) were found not significantly different. 5-y DFS rate of letrozole was better found (87.5%) than exemestane (73.7%) and anastrozole (61.4%). Conclusion: 5-year letrozole administration could be proposed as first-line therapy for postmenopausal women with HR-positive HER2-negative BC. A considerable subject and long-term follow-up are needed for validation.

Real-world outcomes from use of CDK4/6 inhibitors in the management of advanced/metastatic breast cancer in Asia

Background

Oestrogen receptor positive, human epidermal growth factor receptor-2 (HER2) negative breast cancer (BC) is the most frequently diagnosed BC subtype. Combinations of cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) with anti-oestrogen therapy have led to improved survival compared with anti-oestrogen therapy alone for advanced/metastatic BC. The evaluation of CDK4/6i in the real-world facilitates treatment planning, insights into the incidence of drug toxicities, dose modifications including dose delays (DDs) and dose reductions (DRs) and improves prognostic accuracy in subgroups, for example geriatric patients, who are under-represented in clinical trials.

Methods

This multi-centre study analysed retrospective and prospective data from 456 patients treated with CDK4/6i between January 2015 and December 2020. We examined patient characteristics, variation in prescribing practices, efficacy and toxicity outcomes.

Results

In all, 456 patients were included in this study. The median age was 59 (range: 24-92). In total, 85 (19%) were ⩾70 years old. In all, 122 (27%) and 119 (26%) of patients were treated in the first-line and second-line settings, respectively. In total, 25 (5%), 31 (7%) and 145 (32%) of patients had brain, peritoneum and liver metastasis, respectively, at the time of CDK4/6i initiation. On univariate analysis, heavily pre-treated patients and those with distant metastases, involving the liver, brain or peritoneum, had significantly shorter progression-free survival (PFS) and 24-month overall survival (OS). Elderly patients (⩾70) had a shorter PFS; OS results were not mature. Majority of patients (n = 362, 80%) initiated treatment with the United States FDA-approved starting dose of CDK4/6i. In all, 330 (72%) had at least one DD and 217 (48%) patients required at least one DR, but these dose modifications were not associated with poorer survival outcomes. Patients age ⩾70 were more likely to require dose modifications leading to a lower treatment dose. The most common reason for DD/DR was neutropenia (60%) and the incidence of febrile neutropenia was only 2%.

Conclusions

Our study indicates CDK4/6i is effective and safe. Age ⩾ 70, distant metastases to liver, peritoneal or brain were negative prognostic factors. Age ⩾ 70 was associated with significantly increased requirement for dose modification; however, this did not impact survival outcomes. These findings provide reassurance that survival outcomes are not adversely affected in elderly patients when DD/DR is indicated.

Antitumor response and quality of life: is there a need to sacrifice? Clinical observation: long-term and safe control of the disease using a combination of ribociclib with letrozole. Case report

Metastatic luminal B HER2-negative breast cancer (HR+/HER2- mBC) occupies a leading place in the global structure of morbidity and mortality among women. The current gold standard of first-line treatment is the combination of CDK4/6 inhibitors with aromatase inhibitors, among which ribociclib with letrozole is distinguished. According to the MONALEESA-2 study, the addition of ribociclib to letrozole significantly increased the median overall survival to 63.9 months, reducing the risk of death by 24%. The safety profile of the combination is manageable, and the development of adverse events led to the interruption of therapy only in 7.5% of cases. A study of the actual clinical practice of CompLEEment-1 also confirmed the safety and effectiveness of the combination. Maintaining and improving the quality of life is one of the main tasks in the treatment of patients with HR+/HER2- mBC. According to the MONALEESA-2 study, the addition of ribociclib significantly affects the maintenance of quality of life and leads to a decrease in the intensity of pain syndrome. The published data allowed us to assign a combination of ribociclib and letrozole 4 points on the ESMO-MCBS scale. The safety of long-term use of the combination in the first line of treatment illustrated by clinical observation. The patient's progression-free survival during therapy was 40 months, which significantly exceeds the data of the MONALEESA-2 and CompLEEment-1 studies. The maximum effect (partial response according to RECIST 1.1 -40%) achieved after 24 weeks and persisted for 24 months. Clinically, the patient noted a decrease in the severity of the pain syndrome after 8 weeks of therapy. Against the background of therapy, it was possible to maintain the quality of life without sacrificing antitumor efficacy.

Safety and efficacy of ribociclib plus letrozole in patients with HR+, HER2- advanced breast cancer: Results from the Spanish sub-population of the phase 3b CompLEEment-1 trial

BACKGROUND

Breast cancer is the most common malignancy and the second leading cause of cancer-related mortality in Spanish women. Ribociclib in combination with endocrine therapy (ET) has shown superiority in prolonging survival in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) vs. ET alone.

METHODS

CompLEEment-1 is a single-arm, open-label phase 3b trial evaluating ribociclib plus letrozole in a broad population of patients with HR+, HER2- ABC. The primary endpoints were safety and tolerability. Here we report data for Spanish patients enrolled in CompLEEment-1.

RESULTS

A total of 526 patients were evaluated (median follow-up: 26.97 months). Baseline characteristics showed a diverse population with a median age of 54 years. At study entry, 56.5% of patients had visceral metastases and 8.7% had received prior chemotherapy for advanced disease. Rates of all-grade and Grade ≥3 adverse events (AEs) were 99.0% and 76.2%, respectively; 21.3% of patients experienced a serious AE, and 15.8% of AEs led to treatment discontinuation. AEs of special interest of neutropenia, increased alanine aminotransferase, increased aspartate aminotransferase and QTcF prolongation occurred in 77.8%, 14.8%, 11.4% and 4.0% of patients, respectively. Patients aged >70 years experienced increased rates of all-grade and Grade ≥3 neutropenia and anemia. Efficacy results were consistent with the global study.

CONCLUSIONS

Results from Spanish patients enrolled in CompLEEment-1 are consistent with global data showing efficacy and a manageable safety profile for ribociclib plus letrozole treatment in patients with HR+, HER2- ABC, including populations of interest (NCT02941926).

TRIAL REGISTRATION

ClinicalTrials.gov NCT02941926.

[Medical oncology treatment]

Although patients over 65 years of age represent the majority of breast cancer patients, we have limited data on the safety and efficacy of medical oncology treatments in this population. Their indications are based primarily on expert agreement. This literature review discusses the known data on the safety and efficacy of the main medical treatments for breast cancer: chemotherapy, cytokine-dependent kinase inhibitors 4/6, agents targeting human epidermal growth factor receptor-2, novel antibody conjugates, and immunotherapy.

Expert consensus to optimize the treatment of elderly patients with luminal metastatic breast cancer

Most patients diagnosed with luminal metastatic breast cancer (MBC) who are seen in oncology consultations are elderly. MBC in elderly patients is characterized by a higher percentage of hormone receptor (HR) expression and a lower expression of human epidermal growth factor receptor 2 (HER2). The decision regarding which treatment to administer to these patients is complex due to the lack of solid evidence to support the decision-making process. The objective of this paper is to review the scientific evidence on the treatment of elderly patients with luminal MBC. For this purpose, the Oncogeriatrics Section of the Spanish Society of Medical Oncology (SEOM), the Spanish Breast Cancer Research Group (GEICAM) and the SOLTI Group appointed a group of experts who have worked together to establish consensus recommendations to optimize the treatment of this population. It was concluded that the chronological age of the patient alone should not guide therapeutic decisions and that a Comprehensive Geriatric Assessment (CGA) should be performed whenever possible before establishing treatment. Treatment selection for the elderly population should consider the patient’s baseline status, the expected benefit and toxicity of each treatment, and the impact of treatment toxicity on the patient’s quality of life and functionality.

Second-Degree Type 2 Atrioventricular Block Requiring Permanent Cardiac Pacing in Patients on CDK4/6 Inhibitors: Report of Two Cases

Introduction

A wide spectrum of cardiovascular (CV) toxicity is associated with anticancer treatment, and nearly all chemotherapeutic agents can elicit CV toxicity. Inhibitors of cyclin-dependent kinases 4/6 (CDK4/6Is) have become standard of care in the treatment of hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer (MBC). CV side effects are uncommon with CDK4/6Is and only include QT prolongation, with a low incidence rate.

Case Presentation

This paper describes 2 cases of new-onset second-degree type 2 atrioventricular (AV) blocks requiring permanent cardiac pacing involving 2 women with MBC receiving ribociclib or abemaciclib. Both our patients had no known history or risk factors of cardiac disease and a normal 12-lead resting electrocardiogram (ECG) when diagnosed with breast adenocarcinoma. Both patients have been subjected to surveillance for cardiotoxicity with serial ECG and echocardiography. No left ventricular dysfunction or arrhythmia was found during the follow-up, and cardiac biomarkers were normal.

Conclusion

To our knowledge, these are the first cases reported in the literature of new-onset advanced AV blocks in patients under treatment with CDK4/6Is, suggesting the clinical relevance of a more frequent ECG monitoring, besides the QT interval, in these patients.

The History of Early Breast Cancer Treatment

“The story of cancer is the story of human ingenuity, resilience, and perseverance, but also of hubris, paternalism, and misperception” (Siddhartha Mukherjee). The present review discusses the evolution of early breast cancer (BC) treatment philosophy in the last 50 years and the shift from an emphasis on local therapy to an emphasis on systemic precision treatment options.

Ribociclib efficacy in special populations and analysis of patient reported outcomes in the MONALEESA trials

INTRODUCTION

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors abemaciclib, palbociclib and ribociclib radically modified the treatment of hormone receptor-positive/human epidermal growth factor 2-negative advanced breast cancer. Ribociclib efficacy was proved in the phase III MONALEESA-2, -3 and -7 trials. In the first-line setting, ribociclib plus endocrine therapy determined statistically significant improvements in progression-free (PFS) and overall survival (OS) in pre-menopausal (MONALEESA-7) and post-menopausal (MONALEESA-2) women. Likewise, ribociclib and fulvestrant induced a significant PFS and OS benefit in post-menopausal women previously treated with endocrine therapy (MONALEESA-3). Additionally, ribociclib did not affect patient health-related quality of life in all the MONALEESA trials.

AREAS COVERED

We reviewed the results of the available randomized phase III trials testing ribociclib and endocrine therapy in advanced breast cancer, focusing on different patient subgroups and then on health-related quality of life.

EXPERT OPINION

The benefit of ribociclib was consistent across patient subgroups and is maintained in populations with unfavorable features, such as those with endocrine resistance or visceral metastases. Furthermore, the addition of ribociclib to endocrine therapy delays quality of life deterioration and improves pain scores. These results represent a pivotal improvement for the treatment of advanced breast cancer patients receiving CDK4/6 inhibitors.

Art of prevention: The importance of dermatologic care when using aromatase inhibitors

As of January 2021, there are more than 3.8 million women in the United States with a history of breast cancer. The current standard of care for breast cancer involves surgical resection, radiation therapy, adjuvant endocrine therapy, and/or adjuvant chemotherapy. Aromatase inhibitors (AIs) are the gold standard for endocrine therapy in postmenopausal women. Dermatologic adverse events (dAEs) associated with AIs are rare but have been reported in the literature. Commonly reported dAEs include unspecified rash, pruritus, alopecia, vulvovaginal atrophy, vasculitis, and autoimmune/connective tissue disorders. Appropriate preventative strategies and careful management considerations have the potential to optimize the comprehensive care of patients with cancer and improve quality of life. Furthermore, prevention of dAEs can lead to a reduction in cancer treatment interruptions and discontinuations. Herein, we characterize dAEs of AIs and discuss preventative management to reduce the incidence of AI therapy interruption.

Cancer-Related Alopecia: From Etiologies to Global Management

Simple Summary

Although it does not represent a condition that threatens the life of patients, alopecia nevertheless has an essential impact on the quality of life of patients, particularly in terms of the psychological and social aspects. Indeed, while it has long been considered an acceptable side effect in the management of patients, the progressive emergence of a patient-centered approach coupled with a better knowledge of the pathophysiological processes involved has led to a better consideration of alopecia, both on the preventive and palliative sides. Thus, cancerous alopecia can be multifactorial: iatrogenic (in particular via conventional chemotherapy), induced by a vitamin/nutritional deficiency, or even caused by the disease itself. In this state-of-the-art review, we therefore cover alopecia in an exhaustive manner by considering the different mechanisms involved and their frequency as well as the various therapies offered.

Abstract

Alopecia represents a multifaceted challenge with distinct etiologies and consequences. Transposed to the world of oncology, different types of alopecia and molecular pathways have been characterized, allowing a better understanding of the underlying mechanisms. In patients with cancer, alopecia can be iatrogenic (i.e., due to conventional chemotherapies, endocrine therapies, targeted therapies, immunotherapies, radiotherapy and surgery) or a direct consequence of the disease itself (e.g., malnutrition, scalp metastases and paraneoplastic syndromes). Identification of the actual incriminated mechanism(s) is therefore essential in order to deliver appropriate supportive care, whether preventive or curative. On the preventive side, the last few years have seen the advent of the automated cooling cap, a prophylactic approach supported by several randomized clinical trials. On the curative side, although the treatments currently available are limited, several promising therapeutic approaches are under development. Appropriate alopecia management is essential, particularly regarding its psychological repercussions with significant consequences on the quality of life of patients and their family and with a potential impact on treatment compliance.

Optimizing treatment selection, and sequencing decisions for Management of HR-Positive, HER2-Negative advanced breast cancer - Proceedings from breast cancer expert group meeting

PURPOSE

The therapeutic landscape of hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (mBC) has evolved considerably with the introduction of newer targeted agents and their combinations with endocrine therapies. In this scenario, optimizing treatment selection and sequencing is daunting for clinicians. The purpose of this review is to provide evidence-based answers to key clinical questions on treatment selection and sequencing for the management of HR + HER2 - mBC.

DESIGN

A panel of nine key opinion leaders from Argentina, Brazil, Colombia, Mexico, Moscow, Singapore, South Korea, Taiwan, and UAE convened in October 2018. They reviewed the literature and formulated answers to clinical questions on optimizing the management of HR + HER2 - mBC.

RESULTS

Evidence-based answers were formulated for: (1) optimal initial treatment choice; (2) ovarian function suppression, optimal endocrine partner, and role of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors (in premenopausal women); (3) better first-line standard of care than aromatase inhibitors; (4) preferred second-line treatment; (5) treatment of oligometastatic disease; (6) factors influencing first-line single-agent endocrine therapy choice; (7) influence of endocrine resistance on treatment selection; (8) optimal maintenance regimen in visceral crisis; and (9) need for a breast cancer registry for patients with HR + HER2 - mBC. The panel also proposed a treatment-sequencing algorithm for the management of HR + HER2 - mBC.

CONCLUSION

The current article will serve as a comprehensive guide for optimizing the management of HR + HER2 - mBC. The proposed breast cancer registry will help identify unmet needs and develop strategic regional policies to help improve access to optimized care for HR + HER2 - mBC.

Endocrine Treatment and Targeted Therapy for Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer: ASCO Guideline Update

PURPOSE

To update recommendations of the ASCO systemic therapy for hormone receptor (HR)-positive metastatic breast cancer (MBC) guideline.

METHODS

An Expert Panel conducted a systematic review to identify new, potentially practice-changing data.

RESULTS

Fifty-one articles met eligibility criteria and form the evidentiary basis for the recommendations.

RECOMMENDATIONS

Alpelisib in combination with endocrine therapy (ET) should be offered to postmenopausal patients, and to male patients, with HR-positive, human epidermal growth factor receptor 2 (HER2)-negative, PIK3CA-mutated, ABC, or MBC following prior endocrine therapy with or without a cyclin-dependent kinase (CDK) 4/6 inhibitor. Clinicians should use next-generation sequencing in tumor tissue or cell-free DNA in plasma to detect PIK3CA mutations. If no mutation is found in cell-free DNA, testing in tumor tissue, if available, should be used as this will detect a small number of additional patients with PIK3CA mutations. There are insufficient data at present to recommend routine testing for ESR1 mutations to guide therapy for HR-positive, HER2-negative MBC. For BRCA1 or BRCA2 mutation carriers with metastatic HER2-negative breast cancer, olaparib or talazoparib should be offered in the 1st-line through 3rd-line setting. A nonsteroidal aromatase inhibitor (AI) and a CDK4/6 inhibitor should be offered to postmenopausal women with treatment-naïve HR-positive MBC. Fulvestrant and a CDK4/6 inhibitor should be offered to patients with progressive disease during treatment with AIs (or who develop a recurrence within 1 year of adjuvant AI therapy) with or without one line of prior chemotherapy for metastatic disease, or as first-line therapy. Treatment should be limited to those without prior exposure to CDK4/6 inhibitors in the metastatic setting.Additional information can be found at www.asco.org/breast-cancer-guidelines.

[Alopecia and cancers: From basics to clinical practice]

Alopecia, although long considered an unavoidable consequence of cancer therapy, currently presents a multifaceted challenge. The knowledge of the physiology of the hair and consequently of the pathophysiology of alopecia has led to show that there is not one but several types of alopecia. Transposed to the world of oncology, different types of alopecia and subsequently molecular pathways have been characterized, allowing a better understanding of the underlying mechanisms. Thus, in patients with cancer, alopecia can be iatrogenic (chemotherapies, endocrine therapies, targeted therapies, immunotherapies, radiotherapy, surgery) or directly the consequence of the disease itself (malnutrition, scalp metastases, paraneoplastic syndromes). Knowledge of the incriminated mechanism(s) could thus make it possible to deploy an appropriate care component, whether on the preventive or curative sides or in terms of supportive care. These are particularly essential regarding the psychological repercussions caused by alopecia, with significant consequences on the quality of life of patients and with a potential impact on treatment compliance. On the preventive side, the last few years have seen the advent of the automated scalp cooling therapy, supported by several randomized clinical trials. On the curative side, several therapeutic proposals are currently deployed or under development in order to provide relevant treatments.

Updated recommendations regarding the management of older patients with breast cancer: a joint paper from the European Society of Breast Cancer Specialists (EUSOMA) and the International Society of Geriatric Oncology (SIOG)

Breast cancer is increasingly prevalent in older adults and is a substantial part of routine oncology practice. However, management of breast cancer in this population is challenging because the disease is highly heterogeneous and there is insufficient evidence specific to older adults. Decision making should not be driven by age alone but should involve geriatric assessments plus careful consideration of life expectancy, competing risks of mortality, and patient preferences. A multidisciplinary taskforce, including members of the European Society of Breast Cancer Specialists and International Society of Geriatric Oncology, gathered to expand and update the previous 2012 evidence-based recommendations for the management of breast cancer in older individuals with the endorsement of the European Cancer Organisation. These guidelines were expanded to include chemotherapy toxicity prediction calculators, cultural and social considerations, surveillance imaging, genetic screening, gene expression profiles, neoadjuvant systemic treatment options, bone-modifying drugs, targeted therapies, and supportive care. Recommendations on geriatric assessment, ductal carcinoma in situ, screening, primary endocrine therapy, surgery, radiotherapy, adjuvant systemic therapy, and secondary breast cancer were updated.

Overcoming resistance to endocrine therapy in hormone receptor-positive human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer: a meta-analysis and systemic review of randomized clinical trials

New targeted therapies have been developed to overcome resistance to endocrine therapy (ET) and improve the outcome of HR+/HER2- advanced breast cancer (ABC). We conducted a meta-analysis and systemic review on randomized controlled trials evaluating various targeted therapies in combination with ET in HR+/HER2- ABC. PUBMED and EMBASE databases were searched for eligible trials. Hazard ratios (HRs) for progression-free survival (PFS), odds ratios (ORs) for objective response rate (ORR), clinical benefit rate (CBR), and toxicity were meta-analyzed. Twenty-six studies with data on 10 347 patients were included and pooled. The addition of cyclin-dependent kinase 4/6 inhibitors to ET significantly improved median PFS (pooled HR = 0.547, P < 0.001), overall survival (pooled HR= 0.755, P < 0.001), and tumor response rates (ORR, pooled OR= 1.478, P < 0.001; CBR, pooled OR= 1.201, P < 0.001) with manageable toxicities (pooled OR= 3.280, P < 0.001). The mammalian targets of rapamycin inhibitors and exemestane were not clinically beneficial for this pooled population including ET-naïve and ET-resistant patients. Moderate improvement in PFS (pooled HR = 0.686, P < 0.001) yet pronounced toxicities (pooled OR = 2.154, P < 0.001) were noted in the combination of phosphatidylinositol-4,5-bisphosphate 3-kinase inhibitors with fulvestrant. Future studies are warranted to optimize the population and the dosing sequence of these available options.

First clinical experience with CDK4/6 inhibitors in breast cancer therapy

For hormone receptor-positive, HER2-negative breast cancer patients with metastatic or advanced disease, therapy with CDK4/6 inhibitors in addition to aromatase inhibitors (AIs) or to the estrogen receptor (ER) downregulator fulvestrant has resulted in an additional therapy option and a longer progression-free survival. In the Gynecologic-Oncology Clinic, Diakonie-Klinikum Schwäbisch Hall, we followed and registered our initial clinical experience with CDK4/6 inhibitors, following the side effects and tumor response over two years since they were officially approved for general use in Germany. Differences were observed when palbociclib or ribociclib was used in combination with letrozole or anastrozole or fulvestrant. The dynamic side effects and tumor response under therapy with palbociclib or ribociclib were found to be comparable with the main reported data in the official drug information. The CDK4/6 inhibitors have an important and promising role in the therapy of breast cancer patients. Patient age and therapy duration do not influence the use of palbociclib or ribociclib, although it may be important which AI is used in combination with palbociclib.

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

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]).

CDK4/6 Inhibitors in Breast Cancer Treatment: Potential Interactions with Drug, Gene, and Pathophysiological Conditions

Palbociclib, ribociclib, and abemaciclib belong to the third generation of cyclin-dependent kinases inhibitors (CDKis), an established therapeutic class for advanced and metastatic breast cancer. Interindividual variability in the therapeutic response of CDKis has been reported and some individuals may experience increased and unexpected toxicity. This narrative review aims at identifying the factors potentially concurring at this variability for driving the most appropriate and tailored use of CDKis in the clinic. Specifically, concomitant medications, pharmacogenetic profile, and pathophysiological conditions could influence absorption, distribution, metabolism, and elimination pharmacokinetics. A personalized therapeutic approach taking into consideration all factors potentially contributing to an altered pharmacokinetic/pharmacodynamic profile could better drive safe and effective clinical use.

Pharmacogenomic Analysis Reveals CCNA2 as a Predictive Biomarker of Sensitivity to Polo-Like Kinase I Inhibitor in Gastric Cancer

Despite recent innovations and advances in early diagnosis, the prognosis of advanced gastric cancer remains poor due to a limited number of available therapeutics. Here, we employed pharmacogenomic analysis of 37 gastric cancer cell lines and 1345 small-molecule pharmacological compounds to investigate biomarkers predictive of cytotoxicity among gastric cancer cells to the tested drugs. We discovered that expression of CCNA2, encoding cyclin A2, was commonly associated with responses to polo-like kinase 1 (PLK1) inhibitors (BI-2536 and volasertib). We also found that elevated CCNA2 expression is required to confer sensitivity to PLK1 inhibitors through increased mitotic catastrophe and apoptosis. Further, we demonstrated that CCNA2 expression is elevated in KRAS mutant gastric cancer cell lines and primary tumors, resulting in an increased sensitivity to PLK1 inhibitors. Our study suggests that CCNA2 is a novel biomarker predictive of sensitivity to PLK1 inhibitors for the treatment of advanced gastric cancer, particularly cases carrying KRAS mutation.

Different Cardiotoxicity of Palbociclib and Ribociclib in Breast Cancer: Gene Expression and Pharmacological Data Analyses, Biological Basis, and Therapeutic Implications

Breast cancer is the most frequent tumor in women. The recent advent of cyclin-dependent kinase (CDK) 4/6 inhibitors palbociclib and ribociclib has represented a major step forward for patients with hormone receptor-positive breast cancer. These two agents have showed similar efficacy in terms of breast cancer outcome but different cardiotoxic effects. In particular, ribociclib, but not palbociclib, has been associated with QT interval prolongation, and the mechanisms underlying this event are still unclear. In order to clarify such difference, we matched the candidate genes associated with QT interval prolongation with genes whose expression is altered following palbociclib or ribociclib treatment. We also investigated whether pharmacokinetic and pharmacodynamic characteristics, such as IC₅₀ (hERG) [concentration of drug producing 50% inhibition (human ether-à-go-go related gene)] and maximum concentration (C_max), could justify the different effects on QT interval prolongation. Our results show that ribociclib, but not palbociclib, could act by down-regulating the expression of KCNH2 (encoding for potassium channel hERG) and up-regulating SCN5A and SNTA1 (encoding for sodium channels Nav1.5 and syntrophin-α1, respectively), three genes associated with long QT syndrome. Consistent with the cardiotoxicity induced by ribociclib, its IC₅₀ (hERG)/free concentration (C_{max free}) ratio is closer to the safety threshold than that of palbociclib. In summary, we hypothesize that the different cardiotoxicity associated with ribociclib and palbociclib could be due to the alteration of potassium and sodium channels induced by ribociclib. A better comprehension of the mechanisms of cardiac channelopathies and drug-induced QT interval prolongation will be fundamental to avoid serious and potentially lethal adverse events and, as a consequence, optimize the management of breast cancer patients.

Everolimus, Letrozole, and Metformin in Women with Advanced or Recurrent Endometrioid Endometrial Cancer: A Multi-Center, Single Arm, Phase II Study

PURPOSE

Treatment for patients with recurrent endometrioid endometrial cancer (EEC) are limited as paclitaxel is the only second-line chemotherapy with a response rate >13%. Targeting PIK3/mTOR in combination with hormonal therapy has shown promise. The addition of metformin may enhance this response. We conducted a phase II study evaluating everolimus, letrozole, and metformin in advanced/recurrent EEC.

PATIENTS AND METHODS

A Simon two-stage design was employed. Women with ≤2 prior chemotherapy regimens for recurrence were eligible. Pretreatment biopsy was required, followed by everolimus 10 mg orally, letrozole 2.5 mg orally, and metformin 500 mg orally twice a day on a 4-week cycle. The primary endpoint was clinical benefit (CB), defined as complete response (CR), partial response (PR), or stable disease (SD) confirmed at 16 weeks. Patients were treated until progression or toxicity.

RESULTS

Sixty-two patients were enrolled. Median age was 62 years (40-77) with 401 cycles completed, median of 6 cycles (1-31). Fifty-four patients were evaluable for response with a CB rate of 50% (27/54). Best overall response (OR) was PR 28% (15/54) and SD 22% (12/54). Thirteen patients received >12 cycles. Median follow-up was 17.9 months (2-47). Median progression-free survival was 5.7 [95% confidence interval (CI), 3.0-8.1] and OS was 19.6 months (95% CI, 14.2-26.3). Positive progesterone receptor expression was associated with CB (89.5% vs. 27.3%, P = 0.001).

CONCLUSIONS

Everolimus, letrozole, and metformin resulted in 50% CB and 28% OR in women with recurrent EEC. Progesterone receptor-positive tumors may have better response; validation studies are needed.See related commentary by Madariaga et al., p. 523.

Elacestrant (RAD1901) exhibits anti-tumor activity in multiple ER+ breast cancer models resistant to CDK4/6 inhibitors

Background

Addition of CDK4/6 inhibitors (CDK4/6i) to endocrine therapy significantly increased progression-free survival, leading to their approval and incorporation into the metastatic breast cancer treatment paradigm. With these inhibitors being routinely used for patients with advanced estrogen receptor-positive (ER+) breast cancer, resistance to these agents and its impact on subsequent therapy needs to be understood. Considering the central role of ER in driving the growth of ER+ breast cancers, and thus endocrine agents being a mainstay in the treatment paradigm, the effects of prior CDK4/6i exposure on ER signaling and the relevance of ER-targeted therapy are important to investigate. The objective of this study was to evaluate the anti-tumor activity of elacestrant, a novel oral selective estrogen receptor degrader (SERD), in preclinical models of CDK4/6i resistance.

Methods

Elacestrant was evaluated as a single agent, and in combination with alpelisib or everolimus, in multiple in vitro models and patient-derived xenografts that represent acquired and “de novo” CDK4/6i resistance.

Results

Elacestrant demonstrated growth inhibition in cells resistant to all three approved CDK4/6i (palbociclib, abemaciclib, ribociclib) in both ESR1 wild-type and mutant backgrounds. Furthermore, we demonstrated that elacestrant, as a single agent and in combination, inhibited growth of patient-derived xenografts that have been derived from a patient previously treated with a CDK4/6i or exhibit de novo resistance to CDK4/6i. While the resistant lines demonstrate distinct alterations in cell cycle modulators, this did not affect elacestrant’s anti-tumor activity. In fact, we observe that elacestrant downregulates several key cell cycle players and halts cell cycle progression in vitro and in vivo.

Conclusions

We demonstrate that breast cancer tumor cells continue to rely on ER signaling to drive tumor growth despite exposure to CDK4/6i inhibitors. Importantly, elacestrant can inhibit this ER-dependent growth despite previously reported mechanisms of CDK4/6i resistance observed such as Rb loss, CDK6 overexpression, upregulated cyclinE1 and E2F1, among others. These data provide a scientific rationale for the evaluation of elacestrant in a post-CDK4/6i patient population. Additionally, elacestrant may also serve as an endocrine backbone for rational combinations to combat resistance.

CDK4/6 inhibition in low burden and extensive metastatic breast cancer: summary of an ESMO Open-Cancer Horizons pro and con discussion

In December 2017, ESMO Open-Cancer Horizons convened a round-table discussion on the background and latest data regarding cyclin-dependent kinase (CDK)4/6 inhibitors with endocrine therapy (ET) in the treatment of endocrine-sensitive breast cancer (BC). A review on this discussion was published in summer 2018 (https://esmoopen.bmj.com/content/3/5/e000368).Endocrine-sensitive BC with non-visceral disease and limited spread of the metastases.Endocrine-sensitive BC with non-life-threatening visceral involvement. Several open questions were identified, which led to a second ESMO Open discussion on CDK4/6 inhibitors, taking place in December 2018 and covered in this article. The panel discussed two important clinical scenarios and the pro and cons of a treatment approach with CDK4/6 inhibitors for each scenario:Endocrine-sensitive BC with non-visceral disease and limited spread of the metastases.Endocrine-sensitive BC with non-life-threatening visceral involvement. Regarding scenario 1, the panel agreed that CDK4/6 inhibitors should be recommended in first-line therapy for most patients if cost and practicality allow. However, the use of single-agent ET with an aromatase inhibitor in the first-line treatment of these patients is still a possibility for a small group of patients with very limited disease, such as one or two bone lesions or limited lymph node involvement. Regarding scenario 2, chemotherapy is the first approach for patients with endocrine-sensitive metastatic BC with life-threatening visceral involvement because of the need for a faster response. The therapeutic approaches for patients with non-life-threatening visceral involvement are still under debate. Nevertheless, CDK4/6 inhibitors are currently the treatment of choice for most patients with a close follow-up of tumour response. A treatment algorithm has been suggested at the round table.

Aromatase inhibitors and risk of cardiovascular events in breast cancer patients: a systematic review and meta-analysis

BACKGROUND

Cardiovascular events (CVEs) was considered as one of the primary cause to reduce the quality of life in breast cancer patients with aromatase inhibitors (AIs) treatment, which has not been sufficiently addressed. The aim of this study was to assess the correlation between risk of CVEs and AIs in patients with breast cancer.

METHODS

Included studies were obtained from the databases of Embase, Pubmed, Cochrane Library, Clinical Trials.gov, and reference lists. The main outcome measures were overall incidence, odds ratios (ORs), and 95% confidence intervals (CIs). Furthermore, the association and the risk differences among different tumor types, AIs,ages,or treatment regimens were conducted. Fixed-effect or random-effect models were applied in the statistical analyses according to the heterogeneity. Our analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

RESULTS

Seventeen studies, which included 44,411 subjects, were included in our analyses. The overall incidence of CVEs in AIs group was 13.02% (95% CI: 8.15-20.17%) and almost all of the high-grade CVEs occurred in patients treated with AIs. The pooled ORs of CVEs was 0.9940 (95% CI: 0.8545-1.1562). Under sub-group analysis, the incidence of CVEs related to exemestane was higher than that of controls (OR = 1.1564, 95% CI: 1.0656-1.2549), but no statistical differences in risk of CVEs were found in other sub-group analysis. No evidence of publication bias was found for incidence of CVEs in our meta-analysis by a funnel plot.

CONCLUSIONS

These results suggest that patients with breast cancer treated with AIs do not have a significant risk of developing CVEs in comparison with the controls, and exemestane might not be considered as the alternative AI to the breast cancer patients from the perspective of CVEs. Further studies are recommended to investigate this association and the risk differences among different tumor types, AIs or treatment regimens.

Latest Overview of the Cyclin-Dependent Kinases 4/6 Inhibitors in Breast Cancer: The Past, the Present and the Future

Endocrine resistance in hormone receptor positive breast cancer patients urges us to develop novel approaches such as inhibitors of the cyclin-dependent kinases (CDK) 4/6 to reverse its resistance. Nowadays, three selective CDK4/6 inhibitors (Palbociclib, Ribociclib and Abemaciclib) are approved by Federal Drug Administration and the European Medicines Agency for the treatment of advanced and metastatic HR+/HER2- breast cancer. However, no consistent conclusion has been reached to its application in other types of breast cancer. Therefore, the purpose of our study was to overview the clinical trials about the beneficial effects of Palbociclib, Ribociclib and Abemaciclib in breast cancer with their tolerable adverse effects, and discuss their resistant mechanisms thus looking for useful biomarkers to predict the efficiency of the CDK4/6 inhibitors. The CDK4/6 inhibitors application after the support of preclinic and clinic data will be helpful to provide other alternatively suitable strategies for different types of breast cancer patients.

Combining CDK4/6 inhibitors ribociclib and palbociclib with cytotoxic agents does not enhance cytotoxicity

Cyclin-dependent kinases 4 and 6 (CDK4/6) play critical roles in the G₁ to S checkpoint of the cell cycle and have been shown to be overactive in several human cancers. Small-molecule inhibitors of CDK4/6 have demonstrated significant efficacy against many solid tumors. Since CDK4/6 inhibition is thought to induce cell cycle arrest at the G1/S checkpoint, much interest has been focused on combining CDK4/6 inhibitors with cytotoxic agents active against the S or M phase of the cell cycle to enhance therapeutic efficacy. However, it remains unclear how best to combine these two classes of drugs to avoid their potentially antagonistic effects. Here, we test various combinations of highly selective and potent CDK4/6 inhibitors with commonly used cytotoxic drugs in several cancer cell lines derived from lung, breast and brain cancers, for their cell-killing effects as compared to monotherapy. All combinations, either concurrent or sequential, failed to enhance cell-killing effects. Importantly, in certain schedules, especially pre-treatment with a CDK4/6 inhibitor, combining these drugs resulted in reduced cytotoxicity of cytotoxic agents. These findings urge cautions when combining these two classes of agents in clinical settings.

Pharmacogenetics of the systemic treatment in advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) accounts for the majority of primary liver cancers. To date, most patients with HCC are diagnosed at an advanced tumor stage, excluding them from potentially curative therapies (i.e., resection, liver transplantation, percutaneous ablation). Treatments with palliative intent include chemoembolization and systemic therapy. Among systemic treatments, the small-molecule multikinase inhibitor sorafenib has been the only systemic treatment available for advanced HCC over 10 years. More recently, other small-molecule multikinase inhibitors (e.g., regorafenib, lenvatinib, cabozantinib) have been approved for HCC treatment. The promising immune checkpoint inhibitors (e.g., nivolumab, pembrolizumab) are still under investigation in Europe while in the US nivolumab has already been approved by FDA in sorafenib refractory or resistant patients. Other molecules, such as the selective CDK4/6inhibitors (e.g., palbociclib, ribociclib), are in earlier stages of clinical development, and the c-MET inhibitor tivantinib did not show positive results in a phase III study. However, even if the introduction of targeted agents has led to great advances in patient response and survival with an acceptable toxicity profile, a remarkable inter-individual heterogeneity in therapy outcome persists and constitutes a significant problem in disease management. Thus, the identification of biomarkers that predict which patients will benefit from a specific intervention could significantly affect decision-making and therapy planning. Germ-line variants have been suggested to play an important role in determining outcomes of HCC systemic therapy in terms of both toxicity and treatment efficacy. Particularly, a number of studies have focused on the role of genetic polymorphisms impacting the drug metabolic pathway and membrane translocation as well as the drug mechanism of action as predictive/prognostic markers of HCC treatment. The aim of this review is to summarize and critically discuss the pharmacogenetic literature evidences, with particular attention to sorafenib and regorafenib, which have been used longer than the others in HCC treatment.

Meta-analysis of pain and function placebo responses in pharmacological osteoarthritis trials

Objective

To evaluate contextual effects in the form of placebo responses (PRs) for patient-reported pain and function and objectively measured function in osteoarthritis (OA) clinical trials.

Methods

Two authors independently searched major electronic databases from inception to 20 May 2019. Included studies were randomized, placebo-controlled OA trials of pharmacological agents reporting both patient-reported and objectively measured outcomes. PRs for each type of outcome measure were compared by standardized mean differences (SMDs). The placebo response ratio (PRR) assessed the placebo to treatment effect size. The effect sizes of PRs and PRRs were pooled using a random effects model.

Results

Twenty-one trials met the inclusion criteria; 20 were double-blinded with one not reporting on blinding status. Compared with patients’ self-reported outcome (PRO) pain, PRs were significantly lower for PRO function (SMD − 0.16 [95% CI = − 0.28, − 0.05], p = 0.006), objectively measured muscle strength (SMD − 0.34 [95% CI − 0.58, − 0.10], p = 0.006), and range of motion (SMD = − 0.31 [95% CI = − 0.54, − 0.08], p = 0.008) function. Generally, PRs for function outcomes (patient-reported and objectively measured) were similar. The overall PRR for different measures ranged from the smallest (most favorable) for walking time/distance (0.30, 95% CI 0.16 to 0.43) to the largest for PRO pain (0.44, 95% CI 0.23 to 0.65).

Conclusion

Function measures both subjective and objective had less contextual effects than pain measures in OA trials. Our results support the OMERACT-OARSI recommendations to include measures of physical function in all clinical trials of hip and knee OA and suggest that a greater use of function measures might enhance the success rates of pharmacological OA trials. Increasing the availability of mobile health apps should facilitate the acquisition of measured function data.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1951-6) contains supplementary material, which is available to authorized users.

Management of toxicities associated with targeted therapies for HR-positive metastatic breast cancer: a multidisciplinary approach is the key to success

Purpose

Agents targeting HR-positive, HER2-negative locally advanced or metastatic breast cancer have improved patient outcomes compared with conventional single-agent endocrine therapy. Currently, approved targeted agents include everolimus and three CDK4/6 inhibitors, palbociclib, ribociclib, and abemaciclib. Unlike the well-characterized and easily manageable safety profile of endocrine therapies, adverse events associated with targeted therapies are complex and potentially severe. Their prompt recognition and treatment, crucial for prolonged endocrine sensitivity and survival, may be challenging and requires a multidisciplinary effort and a good knowledge of drug interactions.

Methods

We reviewed the current evidence on the drug safety of targeted agents for metastatic breast cancer currently used in clinical practice in Italy, supported by the clinical experience of Italian oncologists with expertise in the field.

Results

All oncologists had used CDK4/6 inhibitors in clinical practice and/or within a clinical trial. The clinical management of toxicities, including dose adjustments, treatment interruptions, and concerns regarding special populations is discussed, and the management of relevant adverse events, related to individual agents and class-specific, toxicities is reviewed. Hematologic toxicities have the greatest impact on clinical management of the disease and on patients. Although toxicities associated with the new treatments result in more visits to the physician and more time and attention with patients, they are manageable, with no need for the oncologist to consult with specialist physicians.

Conclusions

Based on the available evidence and current guidelines, we propose a series of practical recommendations for multidisciplinary clinical management of the various toxicities associated with the addition of targeted agents to endocrine therapy.

Efficacy and Safety of Ribociclib With Letrozole in US Patients Enrolled in the MONALEESA-2 Study

BACKGROUND

In the Mammary Oncology Assessment of LEE011's (Ribociclib's) Efficacy and Safety (MONALEESA-2) study, combination treatment with the selective inhibitor of cyclin-dependent kinases 4/6 ribociclib with letrozole significantly improved progression-free survival (PFS) versus letrozole alone in postmenopausal women with hormone receptor-positive HR⁺/HER2^- advanced breast cancer (ABC). Herein we present results from the subset of US patients enrolled in MONALEESA-2.

PATIENTS AND METHODS

Postmenopausal women with HR⁺/HER2^- ABC without previous treatment for advanced disease were randomized (1:1) to ribociclib 600 mg/d (3 weeks on/1 week off) with letrozole 2.5 mg/d (continuous) or placebo with letrozole. The primary end point was locally assessed PFS.

RESULTS

Overall, 213 US patients were enrolled in MONALEESA-2 (ribociclib, n = 100; placebo, n = 113). Baseline characteristics were similar between treatment groups and consistent with the global population. With a median follow-up of 27 months, 38 (38%) and 29 (26%) patients in the ribociclib and placebo groups, respectively, had continued to receive treatment. Median PFS was 27.6 months with ribociclib and 15.0 months with placebo (hazard ratio, 0.53). The most common all-cause adverse events were neutropenia (ribociclib, 72.0% [n = 72]; placebo, 4.6% [n = 5]), nausea (ribociclib, 69.0% [n = 69]; placebo, 44.0% [n = 48]), and fatigue (ribociclib, 60.0% [n = 60]; placebo, 50.5% [n = 55]). Two patients (ribociclib, 2.0%; placebo, 0%) experienced febrile neutropenia.

CONCLUSION

In the US subset of MONALEESA-2, ribociclib with letrozole showed superior efficacy versus letrozole alone. These findings are consistent with the global population and support first-line use of ribociclib with letrozole in patients with HR⁺/HER2^- ABC.

Comparative efficacy of palbociclib, ribociclib and abemaciclib for ER+ metastatic breast cancer: an adjusted indirect analysis of randomized controlled trials

BACKGROUND

Several trials have demonstrated the benefit of anti-CDK4/6 inhibitors plus endocrine therapy in estrogen receptor-positive (ER+) advanced breast cancer (BC), in first or subsequent lines of therapy. However, due to the lack of direct/indirect comparisons, there are no data demonstrating the superiority of one drug over the other. We compared the effectiveness of palbociclib, ribociclib, and abemaciclib in advanced ER + BC via an indirect adjusted analysis.

METHODS

We performed electronic searches in the PubMed, EMBASE, and Cochrane databases for prospective phase 3 randomized trials evaluating anti-CDK4/6 inhibitors plus endocrine agents. We compared the results with an adjusted indirect analysis of randomized-controlled trials. Outcomes of interest were progression-free survival (PFS), overall response rate (ORR) and G3-4 toxicities occurring in ≥ 5% of patients.

RESULTS

Six trials and six treatment arms including a total of 3743 participants, were included. For PFS and ORR analysis, the three agents were similar in both first- and second-line studies. All G3-4 toxicities were similar, with reduced risk of diarrhea for palbociclib versus abemaciclib (relative risk [RR] 0.13, 95% CI 0.02-0.92; P = 0.04) and of QTc prolongation for palbociclib versus ribociclib (RR 0.02, 95% CI 0-0.83; P = 0.03). Despite different inclusion criteria and length of follow-up, similar features were noticed among second-line studies with the exception of increased risk of anemia G3-4 and diarrhea G3-4 for abemaciclib.

CONCLUSIONS

Based on PFS and ORR results of this indirect meta-analysis, palbociclib, ribociclib, and abemaciclib are equally effective in either first- or second-line therapy for advanced ER + BC. They, however, ported different toxicity profiles.

Addressing physician barriers to administering cyclin-dependent kinases 4 and 6 inhibitors in first-line treatment of hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer

Combination therapy with a cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor and an aromatase inhibitor (AI) for first-line treatment of postmenopausal women with advanced breast cancer (ABC) has demonstrated improvement in progression-free survival (PFS) over AI monotherapy without adding substantial toxicity. However, CDK4/6 inhibitor plus AI therapy is not uniformly used as first-line therapy for ABC, indicating that barriers to CDK4/6 inhibitor use exist. Such barriers may include the following perceptions: patients with bone-only metastases, with a long disease-free interval, or who are older may respond to AI monotherapy and may not benefit from a CDK4/6 inhibitor; tumor response rates may be lower and delayed with CDK4/6 inhibitor plus AI therapy than chemotherapy; the increased incidence of adverse events with CDK4/6 inhibitor plus AI therapy outweighs benefits; and the cost of CDK4/6 inhibitors may be prohibitive. Some of these barriers are addressed with data from follow-up analyses of CDK4/6 inhibitor trials, which have shown a PFS benefit of combination therapy in all subgroups assessed, including older patients, those with bone-only metastatic disease, and those with a long disease-free interval. Tumor response rates with CDK4/6 inhibitor plus AI therapy are comparable to those with first-line cytotoxic chemotherapy. Finally, adverse events associated with CDK4/6 inhibitor plus AI therapy are manageable and occur with decreasing severity during treatment, with similar reports of quality of life to those with AI monotherapy. These data support CDK4/6 inhibitor plus AI therapy as the standard of care in first-line treatment of ABC.

Ribociclib in HR+/HER2- Advanced or Metastatic Breast Cancer Patients

OBJECTIVE

To review the chemistry, pharmacology, pharmacokinetics, safety, and efficacy of ribociclib (LEE011, Kisqali) in hormone receptor-positive/human epidermal growth factor receptor-2-negative (HR+/HER2-) metastatic breast cancer.

DATA SOURCES

A PubMed search was performed using the terms 'Ribociclib', 'Kisqali', and 'LEE011' between May 2018 and November 2018. References of published articles and reviews were also assessed for additional information.

STUDY SELECTION AND DATA EXTRACTION

English-language preclinical and clinical studies on the chemistry, pharmacology, pharmacokinetics, safety, and efficacy of ribociclib were evaluated.

DATA SYNTHESIS

Ribociclib, a cyclin-dependent kinase (CDK) 4/6 inhibitor, is Food and Drug Administration (FDA) approved in combination with endocrine therapy for treatment of HR+/HER2- advanced or metastatic breast cancer in premenopausal/perimenopausal and postmenopausal women. Three phase III trials have evaluated ribociclib in combination with endocrine therapy, including letrozole, anastrozole, tamoxifen, and fulvestrant. These studies found that ribociclib 600 mg/d, 21 days on, 7 days off, leads to a significantly greater median progression-free survival (PFS), ranging from 8 to 13 months. Ribociclib is well tolerated in elderly patients, maintains health-related quality of life, and significantly reduces pain scores. The dose-limiting toxicities found in phase I studies were neutropenia, thrombocytopenia, and QTc prolongation. Common adverse effects seen in phase III trials include neutropenia, leukopenia, nausea, diarrhea, vomiting, and fatigue. Relevance to Patient Care and Clinical Practice: Literature on the safety and efficacy of ribociclib as well as its place in therapy in comparison to other FDA-approved CDK4/6 inhibitors for breast cancer is discussed.

CONCLUSIONS

Ribociclib, when added to endocrine therapy, significantly improves PFS and has manageable toxicity in premenopausal/perimenopausal and postmenopausal women with HR+/HER2- advanced breast cancer.

Use of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in older patients with ER-positive HER2-negative breast cancer: Young International Society of Geriatric Oncology review paper

The current standard of care for the management of estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer has been redefined by the introduction of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors. Although adults aged 65 years and older account for the majority of patients with breast cancer, limited data are available about the age-specific dosing, tolerability, and benefit of CDK4/6 inhibitors in this growing population. Older adults are under-represented in clinical trials and as a result, clinicians are forced to extrapolate from findings in younger and healthier patients when making treatment decisions for older patients. In this article, we review the limited age-specific evidence on the efficacy, toxicity, and quality of life (QoL) outcomes associated with the use of CDK4/6 inhibitors in older adults. We also describe ongoing trials evaluating CDK4/6 inhibitors in the older population and highlight that only a minority of adjuvant and metastatic trials of CDK4/6 inhibitors in the general breast cancer population includes geriatric assessments. Finally, we propose potential strategies to help guide decision making for fit and unfit older patients based on disease endocrine sensitivity, the need for rapid response and geriatric assessment.

CDK4-6 inhibitors in breast cancer: current status and future development

INTRODUCTION

Aberrant cellular proliferation due to dysregulation of the cyclin-dependent kinase (CDK) retinoblastoma (Rb)-pathway occurs in several cancers. Selective inhibition of CDK4/6 is an attractive target particularly in hormone-receptor positive (HR+) metastatic breast cancer (MBC), where it has transformed the treatment of these cancers in recent years. Three CDK4/6 inhibitors, palbociclib, ribociclib, and abemaciclib, have been approved for the treatment of HR+, HER2 negative (HER2-) MBC. Areas covered: We reviewed and compared the pharmacology, clinical efficacy, and toxicity profiles of the three CDK4/6 inhibitors and discussed several challenges in the use of these drugs, particularly in identifying biomarkers, optimizing dosing strategies, and finding best combinations with other therapies. Expert opinion: All three CDK4/6 inhibitors have shown remarkable efficacy when added to endocrine therapy in the treatment of HR+/HER2- MBC with consistent improvements in progression-free survival across all phase III trials. As efficacy appears similar between the drugs, differences in toxicities, dosing schedule, and monitoring requirements may influence the choice of CDK4/6 inhibitor. There is a paucity of predictive biomarkers that have been identified thus far, but a few promising biomarkers have been studied in the preclinical setting and results of ongoing clinical studies are awaited to validate their utility.