Project description:Currently, no targeted therapies are available for metastatic triplenegative breast cancer (mTNBC). We evaluated the safety, efficacy, and biomarkers of response to cabozantinib, a multikinase inhibitor, in patients with mTNBC. We conducted a single arm phase II and biomarker study that enrolled patients with measurable mTNBC. Patients received cabozantinib (60 mg daily) on a 3-week cycle and were restaged after 6 weeks and then every 9 weeks. The primary endpoint was objective response rate. Predefined secondary endpoints included progression-free survival (PFS), toxicity, and tissue and blood circulating cell and protein biomarkers. Of 35 patients who initiated protocol therapy, 3 (9% [95% confidence interval (CI): 2, 26]) achieved a partial response (PR). Nine patients achieved stable disease (SD) for at least 15 weeks, and thus the clinical benefit rate (PR+SD) was 34% [95% CI: 19, 52]. Median PFS was 2.0 months [95% CI: 1.3, 3.3]. The most common toxicities were fatigue, diarrhea, mucositis, and palmar-plantar erythrodysesthesia. There were no grade 4 toxicities, but 12 patients (34%) required dose reduction. Two patients had TNBCs with MET amplification. During cabozantinib therapy, there were significant and durable increases in plasma placental growth factor, vascular endothelial growth factor (VEGF), VEGF-D, stromal cell-derived factor 1a, and carbonic anhydrase IX, and circulating CD3 + cells and CD8 + T lymphocytes, and decreases in plasma soluble VEGF receptor 2 and CD14+ monocytes (all p < .05). Higher baseline concentrations of soluble MET (sMET) associated with longer PFS (p = .03). In conclusion, cabozantinib showed encouraging safety and efficacy signals but did not meet the primary endpoint in pretreated mTNBC. Exploratory analyses of circulating biomarkers showed that cabozantinib induces systemic changes consistent with activation of the immune system and antiangiogenic activity, and that sMET should be further evaluated a potential biomarker of response.Implications for practiceTriple-negative breast cancer (TNBC)-a disease with a dearth of effective therapies-often overexpress MET, which is associated with poor clinical outcomes. However, clinical studies of agents targeting MET and VEGF pathways-alone or in combination-have shown disappointing results. This study of cabozantinib (a dual VEGFR2/MET) in metastatic TNBC, while not meeting its prespecified endpoint, showed that treatment is associated with circulating biomarker changes, and is active in a subset of patients. Furthermore, this study demonstrates that cabozantinib therapy induces a systemic increase in cytotoxic lymphocyte populations and a decrease in immunosuppressive myeloid populations. This supports the testing of combinations of cabozantinib with immunotherapy in future studies in breast cancer patients.
Project description:This single-arm phase II study investigated the efficacy and safety of cabozantinib combined with nivolumab in metastatic triple-negative breast cancer (mTNBC). The primary endpoint was objective response rate (ORR) by RECIST 1.1. Biopsies at baseline and after cycle 1 were analyzed for tumor-infiltrating lymphocytes (TILs), PD-L1, and whole-exome and transcriptome sequencing. Only 1/18 patients achieved a partial response (ORR 6%), and the trial was stopped early. Toxicity led to cabozantinib dose reduction in 50% of patients. One patient had a PD-L1-positive tumor, and three patients had TILs > 10%. The responding patient had a PD-L1-negative tumor with low tumor mutational burden but high TILs and enriched immune gene expression. High pretreatment levels of plasma immunosuppressive cytokines, chemokines, and immune checkpoint molecules were associated with rapid progression. Although this study did not meet its primary endpoint, immunostaining, genomic, and proteomic studies indicated a high degree of tumor immunosuppression in this mTNBC cohort.
Project description:Apatinib is a tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor 2(VEGFR-2). This study was conducted to assess the efficacy and safety of apatinib in patients with non-triple-negative metastatic breast cancer who had received prior chemotherapy for their metastatic disease.This multicenter, open-label, single arm study enrolled patients with non-triple-negative breast cancer, pretreated with anthracycline, taxanes and capecitabine, and who failed in the metastatic setting at least 1 and at most 4 prior chemotherapy regimens and at least one endocrine drug for hormone receptor-positive patients as well as at least one anti-Her2 drug for Her2-positive patients. The primary end point of this study was progression free survival (PFS). Secondary end points included objective response rate (ORR), disease control rate (DCR), overall survival (OS), and toxicity. Apatinib was administered as 500 mg daily on days 1 through 28 of each 4-week cycle.38 patients were enrolled with a median age of 49 years (range, 35 to 62 years) and received apatinib for a median of 4 cycles (range from 0 to 10 cycles). 18 (47.4%) patients experienced dose reduction during treatment. The median relative dose intensity (relative to assigned dose for each cycle) was 82% (range, 45.0% to 100.0%). Median follow-up time was 10.1 months. Median PFS of all 38 patients was 4.0 months (95% confidence interval (CI), 2.8 m - 5.2 m). 36 patients were eligible for efficacy analysis. ORR was 16.7% (6/36). DCR was 66.7% (24/36). Median OS was 10.3 months (95% CI, 9.1 m - 11.6 m). The most common grade 3/4 treatment-related AEs were hypertension (20.5%), hand-foot syndrome (10.3%), and proteinuria (5.1%). Of three possibly drug-related SAEs recorded in the study, 2 (3.4%) deaths occurred within 28 days of last treatment and were both considered to be the result of disease progression. The other one was grade 2 diarrhea needing hospitalization.Apatinib exhibited objective efficacy in heavily pretreated, metastatic non-triple-negative breast cancer with manageable toxicity, and it might be better to be tested in breast cancer with high angiogenesis dependency.ClinicalTrials.gov: NCT01653561.
Project description:PurposeThe identification of patients with metastatic triple-negative breast cancer (mTNBC) who are expected to benefit from platinum-based chemotherapy is of interest. We conducted a single-arm phase II clinical trial of single-agent platinum for mTNBC with biomarker correlates.Patients and methodsPatients with mTNBC received first- or second-line cisplatin (75 mg/m(2)) or carboplatin (area under the concentration-time curve 6) by physician's choice once every 3 weeks. Coprimary end points were objective response rate (RR) and response prediction by p63/p73 gene expression. Secondary and exploratory end points included toxicity assessment, RR in cisplatin versus carboplatin, and RR in molecularly defined subgroups, including BRCA1/2 mutation carriers.ResultsPatients (N = 86; 69 as first-line therapy) received cisplatin (n = 43) or carboplatin (n = 43). RR was 25.6% (95% CI, 16.8% to 36%) and was numerically higher with cisplatin (32.6%) than with carboplatin (18.7%). RR was 54.5% in patients with germline BRCA1/2 mutations (n = 11). In patients without BRCA1/2 mutations (n = 66), exploratory analyses showed that a BRCA-like genomic instability signature (n = 32) discriminated responding and nonresponding tumors (mean homologous recombination deficiency-loss of heterozygosity/homologous recombination deficiency-large-scale state transitions [HRD-LOH/HRD-LST] scores were 12.68 and 5.11, respectively), whereas predefined analysis by p63/p73 expression status (n = 61), p53 and PIK3CA mutation status (n = 53), or PAM50 gene expression subtype (n = 55) did not. Five of the six long-term responders alive at a median of 4.5 years lacked germline BRCA1/2 mutations, and two of them had increased tumor HRD-LOH/HRD-LST scores.ConclusionPlatinum agents are active in mTNBC, especially in patients with germline BRCA1/2 mutations. A measure of tumor DNA repair function may identify patients without mutations who could benefit from platinum therapy agents. Prospective controlled confirmatory trials are warranted.
Project description:Lessons learnedSingle-agent selinexor has limited activity in heavily pretreated patients with metastatic triple-negative breast cancer.Selinexor 60 mg by mouth twice weekly was generally well tolerated with a side-effect profile consistent with previous clinical trials.Future studies of selinexor in this population should focus on combination approaches and a biomarker-driven strategy to identify patients most likely to benefit.BackgroundThis phase II trial evaluated the safety, pharmacodynamics, and efficacy of selinexor (KPT-330), an oral selective inhibitor of nuclear export (SINE) in patients with advanced triple-negative breast cancer (TNBC).MethodsThis phase II trial was designed to enroll 30 patients with metastatic TNBC. Selinexor was given at 60 mg orally twice weekly on days 1 and 3 of each week, three of each 4-week cycle. The primary objective of this study was to determine the clinical benefit rate (CBR), defined as complete response + partial response + stable disease (SD) ≥12 weeks.ResultsTen patients with a median age of 60 years (range 44-71 years) were enrolled between July 2015 and January 2016. The median number of prior chemotherapy lines was 2 (range 1-5). A planned interim analysis for the first stage per protocol was performed. Three patients had SD and seven had progressive disease. On the basis of these results and predefined stoppage rules, the study was halted.ConclusionSelinexor was fairly well tolerated in patients with advanced TNBC but did not result in objective responses. However, clinical benefit rate was 30%, and further investigation of selinexor in this patient population should focus on combination therapies.
Project description:Preclinical data support a role for the IL-6/JAK2/STAT3 signaling pathway in breast cancer. Ruxolitinib is an orally bioavailable receptor tyrosine inhibitor targeting JAK1 and JAK2. We evaluated the safety and efficacy of ruxolitinib in patients with metastatic breast cancer. This was a non-randomized phase II study enrolling patients with refractory, metastatic triple-negative breast cancer. The primary endpoint was objective response by RECIST 1.1. The study was designed to enroll patients whose archival tumor tissue was pSTAT3-positive (T-score >5) by central immunohistochemistry. pSTAT3 staining was available from 171 of 217 consented patients and pSTAT3 T-score was positive in 67/171 (39.2%) tumors, suggesting that JAK-STAT activation is frequent. Twenty-three patients including one patient with inflammatory breast cancer were enrolled. Ruxolitinib was well-tolerated with infrequent grade 3 or higher toxicities with fatigue as the most common toxicity. Among 21 patients who received at least one dose of protocol therapy, no objective responses were observed and the study was closed to further accrual. Pharmacodynamic analyses of baseline vs. cycle 2 biopsies suggest on-target activity, including a significant decrease in the proportion of pSTAT3+ cells in three patients with paired biopsies and downregulation of JAK-STAT target genes and signatures via transcriptional analyses of 11 total baseline and four metastatic biopsies. Immuno-FISH analyses demonstrate intratumoral heterogeneity of pSTAT3 and JAK2 amplification. Ruxolitinib, as a single agent, did not meet the primary efficacy endpoint in this refractory patient population despite evidence of on-target activity.
Project description:Circulating tumor cells (CTC) are prognostic in metastatic breast cancer (MBC). We tested whether EpCAM-based capture system (CellSearch) is effective in patients with triple-negative (TN) MBC, and whether CTC apoptosis and clustering enhances the prognostic role of CTC.CTC enumeration and apoptosis were determined using the CXC CellSearch kit at baseline and days 15 and 29 in blood drawn from TN MBC patients who participated in a prospective randomized phase II trial of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) with or without tigatuzumab. Association between levels of CTC and patient outcomes was assessed using logistic regression, Kaplan-Meier curves, and Cox proportional hazards modeling.Nineteen of 52 (36.5%), 14 of 52 (26.9%), and 13 of 49 (26.5%) patients who were evaluable had elevated CTC (?5 CTC/7.5 mL whole blood) at baseline and at days 15 and 29, respectively. Patients with elevated versus not elevated CTC at each time point had worse progression-free survival (PFS; P = 0.005, 0.0003, 0.0002, respectively). The odds of clinical benefit response for those who had elevated versus low CTC at baseline and days 15 and 29 were 0.25 (95% CI: 0.08-0.84; P = 0.024), 0.19 (95% CI: 0.05-0.17; P = 0.014), and 0.06 (95% CI: 0.01-0.33; P = 0.001), respectively. There was no apparent prognostic effect comparing CTC apoptosis versus non-apoptosis. Presence of CTC cluster at day 15 and day 29 was associated with shorter PFS.CTC were detected using CellSearch assay in approximately one-third of TN MBC patients. Elevated CTC at baseline and days 15 and 29 were prognostic, and reductions in CTC levels reflected response.
Project description:BackgroundCisplatin is an effective agent for triple-negative breast cancer (TNBC) and synergistic activity between cisplatin and capecitabine has been demonstrated by in vitro and in vivo studies. This study was designed as a prospective clinical trial to evaluate the efficacy and safety of capecitabine plus cisplatin (XP) regimen in metastatic TNBC patients pretreated with anthracyclines and taxanes.Patients and methodsThirty-three patients with metastatic TNBC who had anthracyclines and taxanes as prior therapy were treated with capecitabine 2000 mg/m(2) orally on day 1 through 14 plus cisplatin 75 mg/m(2) intravenously on day 1 of a 21-day cycle, followed by capecitabine maintenance medications after a maximum of 6 cycles. The primary end point was objective response rate (ORR) and the secondary end points included progression-free survival (PFS), overall survival (OS) and toxicity profiles.ResultsA total of 162 cycles was given. ORR was 63.6%. Median PFS was 8.2 (95%CI: 4.8-11.6) months in the entire population and 10.8 (95%CI: 6.5-15.1) months in responding patients. Median OS was 17.8 (95%CI: 14.4-21.2) months in all enrolled patients and 25.8 (95%CI: 14.6-37.0) months in responding patients. Most adverse events were mild and manageable, with neutropenia and nausea/vomiting as the most common toxicities. Grade 3/4 toxicities included leukopenia (10, 30.3%), neutropenia (10, 30.3%), anemia (2, 6.1%), thrombocytopenia (1, 3.0%), nausea/vomiting (3, 9.1%), hand-foot syndrome (HFS; 1, 3.0%), and sensory neuropathy (1, 3.0%).ConclusionsCapecitabine plus cisplatin demonstrated an excellent activity and an acceptable safety profile in metastatic TNBC patients pretreated with anthracyclines and taxanes.
Project description:Lessons learnedThe combination of enobosarm and pembrolizumab was well tolerated and showed a modest clinical benefit rate of 25% at 16 weeks. Future trials investigating androgen receptor-targeted therapy in combination with immune checkpoint inhibitors are warranted.BackgroundLuminal androgen receptor is a distinct molecular subtype of triple-negative breast cancer (TNBC) defined by overexpression of androgen receptor (AR). AR-targeted therapy has shown modest activity in AR-positive (AR+) TNBC. Enobosarm (GTx-024) is a nonsteroidal selective androgen receptor modulator (SARM) that demonstrates preclinical and clinical activity in AR+ breast cancer. The current study was designed to explore the safety and efficacy of the combination of enobosarm and pembrolizumab in patients with AR+ metastatic TNBC (mTNBC).MethodsThis study was an open-label phase II study for AR+ (≥10%, 1+ by immunohistochemistry [IHC]) mTNBC. Eligible patients received pembrolizumab 200 mg intravenous (IV) every 3 weeks and enobosarm 18 mg oral daily. The primary objective was to evaluate the safety of enobosarm plus pembrolizumab and determine the response rate. Peripheral blood, tumor biopsies, and stool samples were collected for correlative analysis.ResultsThe trial was stopped early because of the withdrawal of GTx-024 drug supply. Eighteen patients were enrolled, and 16 were evaluable for responses. Median age was 64 (range 36-81) years. The combination was well tolerated, with only a few grade 3 adverse events: one dry skin, one diarrhea, and one musculoskeletal ache. The responses were 1 of 16 (6%) complete response (CR), 1 of 16 (6%) partial response (PR), 2 of 16 (13%) stable disease (SD), and 12 of 16 (75%) progressive disease (PD). Response rate (RR) was 2 of 16 (13%). Clinical benefit rate (CBR) at 16 weeks was 4 of 16 (25%). Median follow-up was 24.9 months (95% confidence interval [CI], 17.5-30.9). Progression-free survival (PFS) was 2.6 months (95% CI, 1.9-3.1) and overall survival (OS) was 25.5 months (95% CI, 10.4-not reached [NR]).ConclusionThe combination of enobosarm and pembrolizumab was well tolerated, with a modest clinical benefit rate of 25% at 16 weeks in heavily pretreated AR+ TNBC without preselected programmed death ligand-1 (PD-L1). Future clinical trials combining AR-targeted therapy with immune checkpoint inhibitor (ICI) for AR+ TNBC warrant investigation.
Project description:Background: The PI3K/AKT/mTOR pathway is an important oncogenic driver in triple-negative breast cancer (TNBC). This study investigated the clinical efficacy and safety of the combination of gemcitabine and cisplatin with everolimus (GPE) in patients with metastatic TNBC. Methods: In phase I, we assessed the maximum tolerated dose (MTD) of GPE in metastatic TNBC patients. Then, using a seamless design, we conducted a randomized phase II trial to compare GPE to GP in terms of progression-free survival (PFS) and toxicity. In addition, we investigated the mutational status of PIK3CA (E542K, E545K, H1047R) in tumor tissues (n=14) and cell-free DNA (cfDNA) from blood samples (n=23) using droplet digital PCR. Results: In phase I (n=9), we found that the MTD of GPE was gemcitabine 800 mg/m2 and cisplatin 30 mg/m2 on days 1 and 8 every 3 weeks along with everolimus 5 mg daily. Phase II was terminated early after 14 patients had been enrolled because of slow recruitment and concerns about efficacy. Results of the combined analysis of phases I and II showed the objective response rate (ORR) of GPE (n=16) was 31.3% and the median PFS was 5.5 months (95% CI, 3.5-7.5). Stomatitis and hematologic toxicities were observed most frequently in the GPE arm. PIK3CA mutations were identified in 8 (57.1%) tumor samples and 17 (73.9%) cfDNA samples; there was no significant association between PIK3CA mutation status and response to GPE treatment. Conclusions: Although the majority of patients with metastatic TNBC demonstrated PIK3CA mutations in cfDNA, the addition of everolimus to gemcitabine/cisplatin did not have a synergistic effect in these patients. Further studies are needed to determine the most effective way to target the PI3K/AKT/mTOR pathway in TNBC patients.