Purpose
The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS).

Patients and Methods
In this phase III study, eligible patients with stage IIIB/IV lung adenocarcinoma were screened for EGFR mutations. Mutation-positive patients were stratified by mutation type (exon 19 deletion, L858R, or other) and race (Asian or non-Asian) before two-to-one random assignment to 40 mg afatinib per day or up to six cycles of cisplatin plus pemetrexed chemotherapy at standard doses every 21 days. The primary end point was PFS by independent review. Secondary end points included tumor response, overall survival, adverse events, and patient-reported outcomes (PROs).

Results
A total of 1,269 patients were screened, and 345 were randomly assigned to treatment. Median PFS was 11.1 months for afatinib and 6.9 months for chemotherapy (hazard ratio [HR], 0.58; 95% CI, 0.43 to 0.78; P = .001). Median PFS among those with exon 19 deletions and L858R EGFR mutations (n = 308) was 13.6 months for afatinib and 6.9 months for chemotherapy (HR, 0.47; 95% CI, 0.34 to 0.65; P = .001). The most common treatmentrelated adverse events were diarrhea, rash/acne, and stomatitis for afatinib and nausea, fatigue, and decreased appetite for chemotherapy. PROs favored afatinib, with better control of cough, dyspnea, and pain.

Conclusion
Afatinib is associated with prolongation of PFS when compared with standard doublet chemotherapy in patients with advanced lung adenocarcinoma and EGFR mutations.

Phase III study of afatinib or cisplatin plus pemetrexed in patients with metastatic lung adenocarcinoma with EGFR mutations

2458 Despite dramatic improvements in treatment over the past 40 years, acute lymphoblastic leukemia (ALL) remains one of the most common causes of death from disease in childhood. Glucocorticoids are among the most effective agents used in the treatment of lymphoid malignancies, and patient response to treatment is an important determinant of long-term outcome in childhood ALL. In spite of its clinical significance, the molecular basis of glucocorticoid resistance is still poorly understood. The aim of this study was to develop an experimental model system to define clinically relevant mechanisms of glucocorticoid resistance in childhood ALL. An in vivo model of childhood ALL has been developed in our laboratory, using patient biopsies established as xenografts in immune-deficient nonobese diabetic severe-combined immunodeficient (NOD/SCID) mice. This model is highly representative of the human disease (Lock et al., Blood, 99: 4100-4108, 2002). The in vivo responses of these xenografts to the glucocorticoid dexamethasone (DEX) correlated significantly with patient outcome (p 1 μM) in xenografts from six patients, five of whom died of their disease. In contrast, four DEX-sensitive xenografts (IC50 values 2-fold in sensitive xenografts within 8 hours of treatment. In contrast, Bim induction was dramatically attenuated in DEX-resistant xenografts. These results have identified a clinically significant and novel mechanism of glucocorticoid resistance in childhood ALL, which occurs downstream of receptor-ligand interactions, but upstream of the signalling pathway resulting in Bim induction and apoptosis.

Novel mechanisms of glucocorticoid resistance in childhood acute lymphoblastic leukemia.

PurposeMONARCH 2 (ClinicalTrialsgov identifier: NCT02107703) compared the efficacy and safety of abemaciclib, a selective cyclin-dependent kinase 4 and 6 inhibitor, plus fulvestrant with fulvestrant alone in patients with advanced breast cancer (ABC)Patients and MethodsMONARCH 2 was a global, double-blind, phase III study of women with hormone receptor-positive and human epidermal growth factor receptor 2-negative ABC who had progressed while receiving neoadjuvant or adjuvant endocrine therapy (ET), ≤ 12 months from the end of adjuvant ET, or while receiving first-line ET for metastatic disease Patients were randomly assigned 2:1 to receive abemaciclib or placebo (150 mg twice daily) on a continuous schedule and fulvestrant (500 mg, per label) The primary end point was investigator-assessed progression-free survival (PFS), and key secondary end points included overall survival, objective response rate (ORR), duration of response, clinical benefit rate, quality of life, and safetyResultsBetween August

MONARCH 2: Abemaciclib in Combination With Fulvestrant in Women With HR+/HER2- Advanced Breast Cancer Who Had Progressed While Receiving Endocrine Therapy.

PurposeAbemaciclib, a cyclin-dependent kinase 4 and 6 inhibitor, demonstrated efficacy as monotherapy and in combination with fulvestrant in women with hormone receptor (HR)–positive, human epidermal growth factor receptor 2 (HER2)–negative advanced breast cancer previously treated with endocrine therapy.MethodsMONARCH 3 is a double-blind, randomized phase III study of abemaciclib or placebo plus a nonsteroidal aromatase inhibitor in 493 postmenopausal women with HR-positive, HER2-negative advanced breast cancer who had no prior systemic therapy in the advanced setting. Patients received abemaciclib or placebo (150 mg twice daily continuous schedule) plus either 1 mg anastrozole or 2.5 mg letrozole, daily. The primary objective was investigator-assessed progression-free survival. Secondary objectives included response evaluation and safety. A planned interim analysis occurred after 189 events.ResultsMedian progression-free survival was significantly prolonged in the abemaciclib arm (hazard ratio, 0.54; 95...

https://ascopubs.org/doi/pdfdirect/10.1200/JCO.2017.75.6155

MONARCH 3: Abemaciclib As Initial Therapy for Advanced Breast Cancer

Importance Statistically significant overall survival (OS) benefits of CDK4 and CDK6 inhibitors in combination with fulvestrant for hormone receptor (HR)–positive, ERBB2 (formerly HER2)-negative advanced breast cancer (ABC) in patients regardless of menopausal status after prior endocrine therapy (ET) has not yet been demonstrated. Objective To compare the effect of abemaciclib plus fulvestrant vs placebo plus fulvestrant on OS at the prespecified interim of MONARCH 2 (338 events) in patients with HR-positive, ERBB2-negative advanced breast cancer that progressed during prior ET. Design, Setting, and Participants MONARCH 2 was a global, randomized, placebo-controlled, double-blind phase 3 trial of abemaciclib plus fulvestrant vs placebo plus fulvestrant for treatment of premenopausal or perimenopausal women (with ovarian suppression) and postmenopausal women with HR-positive, ERBB2-negative ABC that progressed during ET. Patients were enrolled between August 7, 2014, and December 29, 2015. Analyses for this report were conducted at the time of database lock on June 20, 2019. Interventions Patients were randomized 2:1 to receive abemaciclib or placebo, 150 mg, every 12 hours on a continuous schedule plus fulvestrant, 500 mg, per label. Randomization was stratified based on site of metastasis (visceral, bone only, or other) and resistance to prior ET (primary vs secondary). Main Outcomes and Measures The primary end point was investigator-assessed progression-free survival. Overall survival was a gated key secondary end point. The boundaryPvalue for the interim analysis was .02. Results Of 669 women enrolled, 446 (median [range] age, 59 [32-91] years) were randomized to the abemaciclib plus fulvestrant arm and 223 (median [range] age, 62 [32-87] years) were randomized to the placebo plus fulvestrant arm. At the prespecified interim, 338 deaths (77% of the planned 441 at the final analysis) were observed in the intent-to-treat population, with a median OS of 46.7 months for abemaciclib plus fulvestrant and 37.3 months for placebo plus fulvestrant (hazard ratio [HR], 0.757; 95% CI, 0.606-0.945;P = .01). Improvement in OS was consistent across all stratification factors. Among stratification factors, more pronounced effects were observed in patients with visceral disease (HR, 0.675; 95% CI, 0.511-0.891) and primary resistance to prior ET (HR, 0.686; 95% CI, 0.451-1.043). Time to second disease progression (median, 23.1 months vs 20.6 months), time to chemotherapy (median, 50.2 months vs 22.1 months), and chemotherapy-free survival (median, 25.5 months vs 18.2 months) were also statistically significantly improved in the abemaciclib arm vs placebo arm. No new safety signals were observed for abemaciclib. Conclusions and Relevance Treatment with abemaciclib plus fulvestrant resulted in a statistically significant and clinically meaningful median OS improvement of 9.4 months for patients with HR-positive, ERBB2-negative ABC who progressed after prior ET regardless of menopausal status. Abemaciclib substantially delayed the receipt of subsequent chemotherapy. Trial Registration ClinicalTrials.gov identifier:NCT02107703

/pdf/the-effect-of-abemaciclib-plus-fulvestrant-on-overall-4mdi882i7p.pdf

The Effect of Abemaciclib Plus Fulvestrant on Overall Survival in Hormone Receptor-Positive, ERBB2-Negative Breast Cancer That Progressed on Endocrine Therapy-MONARCH 2: A Randomized Clinical Trial

The Authors Reply: In response to Gupta: it is important to point out that during and after kneereplacement surgery, patients given the 300-mg dose of FXI-ASO (ISIS 416858) had a mean factor XI level of 0.20 units per milliliter, and 13 patients had levels below 0.10 units per milliliter. Despite these low levels of factor XI, the rate of bleeding was not increased as compared with that in the enoxaparin group. Therefore, it appears that patients with low levels of factor XI can safely undergo major orthopedic surgery, a procedure considered to be associated with a high risk of bleeding. We agree with Gupta that the safety of factor XI knockdown in other surgical settings is unknown, particularly when tissues with high fibrinolytic activity are involved. However, when FXI-ASO was studied in nonhuman primates, factor XI knockdown to levels similar to those in the patients undergoing knee-replacement surgery had no significant effect on bleeding with the use of a gum-laceration model.1 As suggested by Eggers, factor XII is another potential target. However, activation of factor XI by thrombin would bypass factor XII inhibition. Furthermore, epidemiologic data indicate that patients with congenital factor XI deficiency have a reduced risk of venous thromboembolism.2 For these reasons, we focused on factor XI. Venous thrombi seen in the context of knee surgery are considered to be the result of the combination of stasis (in venous valves) and coagulation activation due to tissue damage. In this respect, it is of note that the observed thrombi in the 300-mg group were rare and small, indicating that the lowering of factor XI levels is very effective in stasis-induced thrombosis.

/pdf/adjuvant-ovarian-suppression-in-premenopausal-breast-cancer-33kj7314tk.pdf

Adjuvant ovarian suppression in premenopausal breast cancer

About 75% of all breast cancers are estrogen receptor (ER)-positive. They generally have a more favorable clinical behavior, prognosis, and pattern of recurrence, and endocrine therapy forms the backbone of treatment. Anti-estrogens (such as tamoxifen and fulvestrant) and aromatase inhibitors (such as anastrozole, letrozole, and exemestane) can effectively control the disease and induce tumor responses in a large proportion of patients. However, the majority of patients progress during endocrine therapy (acquired resistance) and a proportion of patients may fail to respond to initial therapy (de novo resistance). Endocrine resistance is therefore of clinical concern and there is great interest in strategies that delay or circumvent it. A deeper knowledge of the molecular mechanisms that drive endocrine resistance has recently led to development of new strategies that have the promise to effectively overcome it. Many resistance mechanisms have been described, and the crosstalk between ER and growth factor receptor signaling pathways seems to represent one of the most relevant. Compounds that are able to inhibit key elements of these pathways and restore endocrine sensitivity have been studied and more are currently under development. The aim of this review is to summarize the molecular pathophysiology of endocrine resistance in breast cancer and its impact on current clinical management.

/pdf/overcoming-endocrine-resistance-in-metastatic-breast-cancer-1ke7r8gzgz.pdf

Overcoming endocrine resistance in metastatic breast cancer: Current evidence and future directions

Metastatic breast cancer subtypes and central nervous system metastases

e11581 Background: The relapse pattern, survival and response to therapy are known to be different between breast cancer (BC) subtypes defined by combining hormone-receptor (HR) and HER2 status. Ou...

/pdf/metastatic-breast-cancer-subtypes-and-central-nervous-system-1sh1woezzd.pdf

Metastatic breast cancer subtypes and central nervous system metastases.

Background Central nervous system (CNS) involvement contributes to significant morbidity and mortality in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) and represents a major challenge for clinicians. Liquid biopsy of cerebrospinal fluid (CSF)-derived circulating tumour DNA (ctDNA) harbours clinically relevant genomic alterations in patients with CNS metastases and could be effective in tracking tumour evolution. Methods In a HER2-positive mBC patient with brain metastases, we applied droplet digital PCR (ddPCR) and next-generation whole exome sequencing (WES) analysis to measure ctDNA dynamic changes in CSF and plasma collected during treatment. Results Baseline CSF-derived ctDNA analysis revealed TP53 and PIK3CA mutations as well as ERBB2 and c MYC amplification. Post-treatment ctDNA analysis showed decreased markers level in plasma, consistent with extra-CNS disease control, while increased in the CSF, confirming poor treatment benefit in the CNS. Discussion Analysis of ctDNA in the CSF of HER2-positive mBC is feasible and could represent a useful companion for clinical management of brain metastases.

Elena Geuna

Papers

Adjuvant ovarian suppression in premenopausal breast cancer

Overcoming endocrine resistance in metastatic breast cancer: Current evidence and future directions

Metastatic breast cancer subtypes and central nervous system metastases

Metastatic breast cancer subtypes and central nervous system metastases.

Genotyping tumour DNA in cerebrospinal fluid and plasma of a HER2-positive breast cancer patient with brain metastases