Modelling hospital disinfectant against multi-drug-resistant dry surface biofilms grown under artificial human sweat

BACKGROUND

Dry surface biofilms (DSBs) have been found abundantly across hospital surfaces within intensive care units and may explain how nosocomial pathogens can remain virulent and persist on surfaces for extended periods. Testing standards governing the performance of disinfectant products employ planktonic models under routine growth conditions, which are known to be less tolerant than their biofilm counterpart.

AIM

To evaluate biofilm models cultured under artificial human sweat (AHS), a source of nutrient expected on touch surfaces, to assess the antimicrobial performance of common cleaning agents, including a quaternary ammonium, hydrogen peroxide and active chlorine.

METHODS

Five single-species biofilms, using pathogenic bacteria such as Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis, were generated on stainless-steel substrates using a sedimentation protocol under both AHS and nutrient-rich conditions for a direct comparison of phenotypic tolerance. The biofilm models were grown over five days followed by desiccation cycles, before being submerged into the disinfectant solutions for up to 25 min. Epifluorescence (EF) microscopy using LIVE/DEAD™ stain was used to visualize microcolony viability.

FINDINGS

The results revealed biofilms cultured under AHS exhibited a greater antimicrobial tolerance and reduced speed of kill for all cleaning agents compared with the routine media; an average reduction of 72.4% vs 96.9%, respectively. EF microscopy revealed traces of viable bacteria across all coupons after disinfection indicating a potential opportunity for regrowth and recontamination.

CONCLUSION

The notable difference in biocidal performance between the two growth conditions highlights potential pitfalls within current antimicrobial test standards, and the importance of accurate representation of the microbial challenge.

An automated contact model for transmission of dry surface biofilms of Acinetobacter baumannii in healthcare

BACKGROUND

Dry surface biofilms (DSBs) have been recognized across environmental and equipment surfaces in hospitals and could explain how microbial contamination can survive for an extended period and may play a key role in the transmission of hospital-acquired infections. Despite little being known on how they form and proliferate in clinical settings, DSB models for disinfectant efficacy testing exist.

AIM

In this study we develop a novel biofilm model to represent formation within hospitals, by emulating patient to surface interactions.

METHODS

The model generates a DSB through the transmission of artificial human sweat (AHS) and clinically relevant pathogens using a synthetic thumb capable of emulating human contact. The DNA, glycoconjugates and protein composition of the model biofilm, along with structural features of the micro-colonies was determined using fluorescent stains visualized by epifluorescence microscopy and compared with published clinical data.

RESULTS

Micrographs revealed the heterogeneity of the biofilm across the surface; and reveal protein as the principal component within the matrix, followed by glycoconjugates and DNA. The model repeatably transferred trace amounts of micro-organisms and AHS, every 5 min for up to 120 h on to stainless-steel coupons to generate a biofilm model averaging 1.16 × 103 cfu/cm2 falling within the reported range for clinical DSB (4.20 × 102 to 1.60 × 107 bacteria/cm2).

CONCLUSION

Our in vitro DSB model exhibits many phenotypical characteristics and traits to those reported in situ. The model highlights key features often overlooked and the potential for downstream applications such as antibiofilm claims using more realistic microbial challenges.

Homogenization modelling of antibiotic diffusion and adsorption in viral liquid crystals

Systems of rod-shaped viruses have long been important to the science of living liquid crystals, as their monodispersity and uniform charge make them convenient model systems. Recently, it was shown that, upon the addition of polymers, suspensions of rod-shaped viruses form liquid crystals that are linked with increased tolerance of bacteria against antibiotics. We use homogenization to obtain effective equations describing antibiotic diffusion through these liquid crystals. The analytical results of homogenization are compared with numerical results from an exact microscopic model, showing good agreement and thus allowing us to identify the key parameters behind the process. Our modelling shows that the adsorption plays a key role in increasing antibiotic diffusion time and therefore the presence of nematic rod-shaped viruses may increase antibiotic tolerance through physical mechanisms alone. These results demonstrate the applicability of homogenization as an analytical tool to systems of liquid crystalline viruses, with relatively straightforward extension to more complex problems such as liquid crystalline biofilms, other biological liquid crystals and biological systems with different types of local structural order.

Abstract LB033: Longitudinal ctDNA changes in patients with long-term response to palbociclib combination therapy for advanced breast cancer: A preliminary analysis from the real-world POLARIS study

Background

POLARIS is an ongoing, prospective, real-world (RW) study of palbociclib (PAL) in patients (pts) with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer (HR+/HER2- ABC). A biomarker goal of this study was to evaluate serial changes in circulating tumor DNA (ctDNA) dynamics among pts with long-term clinical response to PAL plus endocrine therapy (ie, received ≥18 cycles).

Methods

The data set included pts who received PAL combination therapy, gave consent for blood collection to obtain ctDNA, and had long-term clinical response. The Guardant360 Next-Generation Sequencing platform, which analyzed approximately 73 genes, was used to sequence ctDNA for somatic single-nucleotide variants, including copy number variants. Longitudinal ctDNA changes (at baseline and various time points) and the RW clinical response to PAL are described.

Results

As of December 17, 2020, 35 pts of 1280 enrolled received ≥18 cycles of PAL combination therapy, with blood samples collected over a minimum of a 24-month period. Pts received PAL plus an aromatase inhibitor (n=16) or fulvestrant (n=19). Median age was 64 years. Thirty pts (85.7%) were white, 29 (82.9%) were postmenopausal, 31 (88.6%) had an Eastern Cooperative Oncology Group score of 0 or 1, 12 (34.3%) had visceral disease, 9 (25.7%) had de novo disease, and 24 (68.6%) had recurrent disease. Six pts (17.1%) had a RW best overall response (BOR) of complete response (CR), 9 (25.7%) had partial response (PR), and 20 (57.1%) had stable disease (SD). Two pts had disease progression resulting in change of therapy at cycles 25 and 38, respectively. Biomarker samples were collected from a median (range) total number of 9 (3-12) visits. The median (range) number of somatic variants detected was 4 (0-11) and included the most prevalent somatic mutations (eg, PIK3CA, TP53, BRCA1/2, FGFR2, GATA3). No ctDNA mutations were detected in 6 pts (17%) post baseline up to 24 months. Among 15 pts who achieved CR/PR, 12 (80%) either had no detectable or sustained very low ctDNA burden or had corresponding ctDNA decrease. Among 16 pts who remained with SD, 12 (75%) either had no detectable or sustained very low ctDNA burden or had ctDNA decrease. Among 8 pts whose disease progressed, 5 (63%) had an increasing trend in ctDNA mutation frequency.

Conclusions

This study is among the first to provide serial blood-based tumor genotyping data from routine clinical practice. Interim data indicate that even pts with ongoing detectable ctDNA have a BOR of CR, PR, or SD with PAL for HR+/HER2- ABC, suggesting certain mutations might not be drivers of PAL resistance. Dynamic changes of ctDNA mutations may be predictive for treatment response, and may have clinical utility in disease surveillance monitoring. Additional longitudinal data will be presented.

Pfizer; NCT03280303

Citation Format: Joanne L. Blum, Aditya Bardia, Sharon Wilks, Steven L. McCune, Carrie L. Dul, John J. Migas, Derrick W. Spell, Zhe Zhang, Yuan Liu, Yao Wang, Debu Tripathy. Longitudinal ctDNA changes in patients with long-term response to palbociclib combination therapy for advanced breast cancer: A preliminary analysis from the real-world POLARIS study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB033.

Preference for the fixed-dose combination of pertuzumab and trastuzumab for subcutaneous injection in patients with HER2-positive early breast cancer (PHranceSCa): A randomised, open-label phase II study

AIM

The aim of the study was to assess patient preference for the fixed-dose combination of pertuzumab and trastuzumab for subcutaneous injection (PH FDC SC) in patients with HER2-positive early breast cancer in PHranceSCa (NCT03674112).

MATERIALS AND METHODS

Patients who completed neoadjuvant P + H + chemotherapy + surgery were randomised 1:1 to three intravenous (IV) P + H cycles followed by three cycles of PH FDC SC or vice versa (crossover) and then chose subcutaneous (SC) injection or IV infusion to continue up to 18 cycles (continuation). Assessments were via patient and healthcare professional (HCP) questionnaires.

RESULTS

One hundred and sixty patients were randomised (cut-off: 24 February 2020); 136 (85.0%, 95% confidence interval: 78.5-90.2%) preferred SC; 22 (13.8%) preferred IV; 2 (1.3%) had no preference. The main reasons for SC preference were reduced clinic time (n = 119) and comfort during administration (n = 73). One hundred and forty-one patients (88.1%) were very satisfied/satisfied with SC injection versus 108 (67.5%) with IV infusion; 86.9% chose PH FDC SC continuation. HCP perceptions of median patient treatment room time ranged from 33.0-50.0 min with SC and 130.0-300.0 min with IV. Most adverse events (AEs) were grade 1/2 (no 4/5s); serious AE rates were low. AE rates before and after switching were similar (cycles 1-3 IV → cycles 4-6 SC: 77.5% → 72.5%; cycles 1-3 SC → cycles 4-6 IV: 77.5% → 63.8%).

CONCLUSION

Most patients strongly preferred PH FDC SC over P + H IV. PH FDC SC was generally well tolerated, with no new safety signals (even when switching), and offers a quicker alternative to IV infusion.

Efficacy and Safety of Weekly Paclitaxel With or Without Oral Alisertib in Patients With Metastatic Breast Cancer: A Randomized Clinical Trial

IMPORTANCE

Elevated expression of AURKA adversely affects prognosis in estrogen receptor (ER)-positive and ERBB2 (formerly HER2)-negative and triple-negative breast cancer and is associated with resistance to taxanes.

OBJECTIVE

To compare paclitaxel alone vs paclitaxel plus alisertib in patients with ER-positive and ERBB2-negative or triple-negative metastatic breast cancer (MBC).

DESIGN, SETTING, AND PARTICIPANTS

In this randomized clinical trial conducted with the US Oncology Network, participants were randomized to intravenous (IV) paclitaxel 90 mg/m2 on days 1, 8, and 15 on a 28-day cycle or IV paclitaxel 60 mg/m2 on days 1, 8, and 15 plus oral alisertib 40 mg twice daily on days 1 to 3, 8 to 10, and 15 to 17 on a 28-day cycle. Stratification was by prior neo or adjuvant taxane and by line of metastatic therapy. Eligible patients were those who had undergone endocrine therapy, 0 or 1 prior chemotherapy regimens for MBC, more than 12 months treatment-free interval from neo or adjuvant taxane therapy, and with measurable or evaluable lytic bone-disease. Data were analyzed from March 2019 through May 2019.

MAIN OUTCOMES AND MEASURES

The main outcome was progression-free survival (PFS) with secondary end points of overall survival (OS), overall response rate, clinical benefit rate, safety, and analysis of archival breast cancer tissues for molecular markers associated with benefit from alisertib.

RESULTS

A total of 174 patients were randomized, including with 86 randomized to paclitaxel and 88 patients randomized to paclitaxel plus alisertib, and 169 patients received study treatment. The final cohort included 139 patients with a median (interquartile range [IQR]) age of 62 (27-84) years with ER-positive and ERBB2-negative MBC, with 70 randomized to paclitaxel and 69 randomized to paclitaxel plus alisertib. The TNBC cohort closed with only 35 patients enrolled due to slow accrual and were not included in efficacy analyses. The median (IQR) follow-up was 22 (10.6-25.1) months, and median (IQR) PFS was 10.2 (3.8-15.7) months with paclitaxel plus alisertib vs 7.1 (3.8-10.6) months with paclitaxel alone (HR, 0.56; 95% CI, 0.37-0.84; P = .005). Median (IQR) OS was 26.3 (12.4-37.2) months for patients who received paclitaxel plus alisertib vs 25.1 (11.0-31.4) months for paclitaxel alone (HR, 0.89; 95% CI, 0.58-1.38; P = .61). Grade 3 or 4 adverse events occurred in 56 patients (84.8%) receiving paclitaxel plus alisertib vs 34 patients (48.6%) receiving paclitaxel alone. The main grade 3 or 4 adverse events with paclitaxel plus alisertib vs paclitaxel alone were neutropenia (50 patients [59.5%] vs 14 patients [16.4%]), anemia (8 patients [9.5%] vs 1 patient [1.2%]), diarrhea (9 patients [10.7%] vs 0 patients), and stomatitis or oral mucositis (13 patients [15.5%] vs 0 patients). One patient receiving paclitaxel plus alisertib died of sepsis.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that the addition of oral alisertib to a reduced dose of weekly paclitaxel significantly improved PFS compared with paclitaxel alone, and toxic effects with paclitaxel plus alisertib were manageable with alisertib dose reduction. These data support further evaluation of alisertib in patients with ER-positive, ERBB2-negative MBC.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02187991.

Phase I Study of Elacestrant (RAD1901), a Novel Selective Estrogen Receptor Degrader, in ER-Positive, HER2-Negative Advanced Breast Cancer

PURPOSE

This phase I study (RAD1901-005; NCT02338349) evaluated elacestrant, an investigational oral selective estrogen receptor degrader (SERD), in heavily pretreated women with estrogen receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer, including those with estrogen receptor gene alpha (ESR1) mutation. The primary objective was to determine the maximum tolerated dose and/or recommended phase II dose (RP2D).

METHODS

The study consisted of a 3 + 3 design (elacestrant capsules) followed by expansion at RP2D (400-mg capsules, then 400-mg tablets) for the evaluation of safety and antitumor activity. Elacestrant was taken once daily until progression or intolerability.

RESULTS

Of 57 postmenopausal women enrolled, 50 received RP2D (400 mg once daily): median age, 63 years; median three prior anticancer therapies, including cyclin-dependent kinase 4,6 inhibitors (CDK4/6i; 52%), SERD (52%), and ESR1 mutation (circulating tumor DNA; 50%). No dose-limiting toxicities occurred; the most common adverse events at RP2D (400-mg tablet; n = 24) were nausea (33.3%) and increased blood triglycerides and decreased blood phosphorus (25.0% each). Most adverse events were grade 1-2 in severity. The objective response rate was 19.4% (n = 31 evaluable patients receiving RP2D), 15.0% in patients with prior SERD, 16.7% in patients with prior CDK4/6i, and 33.3% in patients with ESR1 mutation (n = 5/15). The clinical benefit rate (24-week) was 42.6% overall (n = 47 patients receiving RP2D), 56.5% (n = 23, ESR1 mutation), and 30.4% (n = 23, prior CDK4/6i). Elacestrant clinical benefit was associated with decline in ESR1 mutant allele fraction.

CONCLUSION

Elacestrant 400 mg orally once daily has an acceptable safety profile and demonstrated single-agent activity with confirmed partial responses in heavily pretreated patients with estrogen receptor-positive metastatic breast cancer. Notably, responses were observed in patients with ESR1 mutation as well as those with prior CDK4/6i and prior SERD. A phase III trial investigating elacestrant versus standard endocrine therapy is ongoing.

A phase Ib/II study of eribulin (ERI) plus pembrolizumab (PEMBRO) in metastatic triple-negative breast cancer (mTNBC) (ENHANCE 1)

1015

Background: As monotherapies, both ERI (a chemotherapeutic microtubule inhibitor) and PEMBRO (a programmed death [PD]-1 blocking immunotherapy) have shown promising antitumor activity in mTNBC. Emerging data suggest that the addition of immunotherapy to traditional chemotherapy holds promise for mTNBC. This open-label, single-arm, phase 1b/2 study evaluated the safety and efficacy of ERI + PEMBRO in mTNBC. Methods: Patients (pts) with mTNBC and ≤2 prior systemic anticancer therapies for metastatic disease were enrolled and stratified by prior number of therapy (Stratum 1, 0; Stratum 2, 1–2). Pts received IV ERI 1.4 mg/m2 on day (d)1 and d8 and IV PEMBRO 200 mg on d1 of a 21-d cycle. The primary objectives were safety and objective response rate (ORR per RECIST 1.1 by independent imaging review). Assessments also included efficacy outcomes by PD ligand-1 (PD-L1) expression status; PD-L1+ was defined as a combined positive score ≥1 using the PD-L1 IHC 22C3 pharmDx. Results: As of data cutoff (July 31, 2019), 167 pts (Stratum 1, n=66; Stratum 2, n=101) were enrolled and treated. No dose-limiting toxicities were observed. The most common treatment-emergent adverse events were fatigue (66%), nausea (57%), peripheral sensory neuropathy (41%), alopecia (40%), and constipation (37%). No deaths were considered treatment related. The overall ORR was 23.4% (95% CI: 17.2–30.5). Efficacy outcomes by PD-L1 status (PD-L1+, n=74; PD-L1-, n=75) and stratum are presented (table). Conclusions: ERI + PEMBRO has activity in pts with mTNBC. There was a trend toward more robust activity for the combination among patients with PD-L1+ tumors compared to PD-L1- tumors in the first-line setting (Stratum 1); whereas, in the later-line setting (Stratum 2) similar survival outcomes were observed among the PD-L1+ and PD-L1- pts. ERI + PEMBRO shows promise for mTNBC with efficacy that appears greater than historical reports of either agent alone. Clinical trial information: NCT02513472 . [Table: see text]

SGNLVA-001: A phase I open-label dose escalation and expansion study of SGN-LIV1A administered weekly in breast cancer

TPS1104

Background: LIV-1 is a highly prevalent transmembrane protein in breast cancer cells. Ladiratuzumab vedotin (LV), SGN-LIV1A, is an investigational antibody-drug conjugate (ADC) that targets LIV-1 via a humanized IgG1 monoclonal antibody conjugated to monomethyl auristatin E (MMAE) by a protease-cleavable linker. LV is internalized when it binds LIV-1 on cell surfaces and MMAE is released, which binds tubulin and induces apoptosis. LV has been shown to be active and tolerable in metastatic breast cancer (mBC) at a recommended dose of 2.5 mg/kg every 21 days (Modi 2017). More frequent, fractionated dosing has improved the activity and/or safety of other ADCs. Thus, this study is actively accruing subjects with metastatic triple negative breast cancer (mTNBC; estrogen receptor (ER)/progesterone receptor (PR)/human epidermal growth factor receptor 2 (HER2) receptor-negative) and endocrine-resistant ER+ or PR+ (hormone receptor [HR+])/HER2-negative mBC to test weekly dosing of LV (Days 1, 8, and 15 of every 3-week cycle). Methods: This study is enrolling up to 82 subjects (42 HR+/HER2-negative and 40 mTNBC) into dose escalation and dose expansion cohorts (NCT01969643). Eligible subjects are females ≥18 years old with pathologically and radiologically confirmed metastatic HR+/HER2-negative or mTNBC with at least 1 measurable lesion per RECIST v1.1. Subjects with HR+/HER2-negative disease must have received no more than 1 prior line of cytotoxic chemotherapy in the locally advanced (LA)/mBC setting, either as single agent or combination therapy. Subjects with mTNBC must have received 1 prior line of cytotoxic chemotherapy in the LA/mBC setting. Progression within 6 months of completion of neoadjuvant or adjuvant therapy is considered an LA/mBC regimen. Subjects must have adequate organ function, ECOG status of ≤1, and no ≥ Grade 2 peripheral neuropathy. Subjects with brain lesions must have received definitive treatment of the lesions. Prior therapy with MMAE-containing agents is not allowed. Dose escalation follows the modified toxicity probability interval method (Ji 2010). Dose expansion cohorts will provide data about activity and tolerability. Tumor assessments will be conducted every 2 cycles per RECIST v1.1 and all subjects will be followed for safety. Pharmacokinetics and markers of pharmacodynamics will be assessed. Primary safety endpoint is the incidence of adverse events and dose-limiting toxicities. Key efficacy endpoints include confirmed overall response rate, duration of response, and progression-free survival. Clinical trial information: NCT01969643 .

Distinct molecular profiles of interval and screen-detected tumors in a real-world breast cancer registry

e15587

Background: Interval breast cancers (BC) are detected between routine screening mammograms and are associated with worse prognosis, requiring more aggressive treatment compared to screen-detected BC identified during scheduled mammograms. Identifying molecular differences between interval BC and screen detected BC may lay the foundation for developing novel therapies. In this study, we compared gene expression profiles of interval BC to screen-detected BC. Methods: This analysis included a subset of 2260 patients enrolled in the FLEX Registry (NCT03053193), an ongoing, prospective study evaluating primary tumor samples from stage I-III BC patients who receive 70-gene risk of recurrence testing (70GS), 80-gene molecular subtyping (80GS), and consent to collection of clinically annotated full genome data. Interval BC were diagnosed < 12 months following a normal screening mammogram. Breast tumors were classified by 70GS as having a Low Risk (LR) or High Risk (HR) of distant metastases. Tumors were classified as Luminal, HER2, or Basal type by 80GS. Differential gene expression analysis was performed with limma and subsequent pathway analysis with DAVID and GSEA. Differences in the proportion of 70GS or 80GS results, 70GS index, and Ki67 were assessed by Chi-squared test or t-test. Results: In this study, 81% (1834/2260) of patients had screen-detected BC and 19% (426) had interval BC. A higher proportion of interval BC (51%) were HR compared to screen-detected BC (44%; p = 0.01). Most LR tumors were invasive ductal carcinoma (78% interval and 73% screen-detected) and over 99% were Luminal type. Between the two LR groups, 70GS indices were similar and there was no significant difference in transcriptional profiles. Basal and HER2 subtypes were more frequent among HR interval BC compared to screen-detected BC (p = 0.03). HR interval BC had 70GS indices of higher risk compared to HR screen-detected BC (p = 0.02). Differentially expressed genes in HR interval BC compared to HR screen-detected BC were associated with MYC signaling and mitosis, which was concordant with higher Ki67 by IHC (p = 0.007). Conclusions: This real-world data analysis shows interval BC are not all biologically High Risk and can be further stratified by the 70GS, aiding in treatment decisions. Preliminary results suggest that following 70GS LR classification, there is no biological difference between interval BC and screen-detected BC. In contrast, there are distinct biological processes associated with HR interval BC, which may have implications in the management of these cancers. Clinical trial information: NCT03053193.

Abstract PD7-10: Randomized, multicenter phase II trial of weekly paclitaxel with or without the oral selective aurora kinase A (AURKA) inhibitor, Alisertib, in patients with ER+ HER2- metastatic breast cancer

Elevated expression of AURKA adversely affects prognosis in ER+ breast cancer and is associated with resistance to taxanes, endocrine therapy, and PI3K inhibitors. A recent randomized phase II trial of combined paclitaxel plus alisertib (P+A) in recurrent ovarian cancer patients (pts) showed improved progression-free survival (PFS) compared to paclitaxel (P) alone (Falchook G. JAMA Oncol 2019). We conducted a randomized phase II trial of P alone versus P+A in pts with ER+ HER2- metastatic breast cancer (MBC). Methods: The primary objective of the trial was PFS in the intent-to-treat (ITT) population with secondary endpoints of overall survival (OS), overall response rate (ORR), clinical benefit rate (CBR; CR+PR+SD&gt;6 mos), safety and analysis of archival breast cancer for molecular predictors of benefit from alisertib. ER+ HER2- MBC pts who had had prior endocrine therapy, 0 or 1 prior chemotherapy regimens for MBC, &gt; 12 mos treatment-free interval from neo/adjuvant taxane therapy, and who had measurable or evaluable lytic bone disease were randomized to receive P 90 mg/m2 IV D1, 8, 15 on a 28-day cycle or P 60mg/m2 D1, 8, 15 plus A 40 mg PO BID D1-3, 8-10, 15-17 on a 28-day cycle until disease progression or unacceptable toxicity. Pts were stratified by prior neo/adjuvant taxane (yes/no) and by whether they were receiving first (1L)- or second (2L)-therapy for MBC. Proportions of ORR and CBR were compared using Chi-square test between the two study arms. Kaplan-Meier estimator was applied to estimate OS and PFS and univariate Cox regression was used to assess the hazard ratio of study treatment. Results: 139 pts were randomized (69 to P+A; 70 to P) in the US Oncology Network between 2/2015 and 2/2018 and 136 pts received treatment on trial. At data cut-off, 76% of pts had had a documented PFS event and the median followup was 19.7 mos. The median age was 62 and 69% of pts received trial therapy as 1L treatment; 41% had had prior neo/adjuvant taxane therapy. Median PFS in the ITT population was 10.2 mos with P+A vs 7.1 mos with P alone, HR 0.56, 95% CI 0.37-0.84, p=0.005. Median OS was 29.8 mos with P+A vs 24.4 mos with P alone, HR 0.85, p=0.486. ORR and CBR in the response evaluable population were 31% and 67%, respectively, in the P+A arm vs 34% and 57%, respectively, in the P alone arm (p&gt;0.05). Grade 3/4 adverse events (AEs) occurred in 83% of P+A pts vs 47% with P alone. The main grade 3/4 AEs with P+A vs P were neutropenia 59% vs 15%, anemia 10% vs 1%, febrile neutropenia 1.5% vs 0, diarrhea 11% vs 0, stomatitis 15% vs 0, peripheral neuropathy 1.5% vs 9%. 1 pt died of sepsis with P+A. Conclusions: Addition of oral A to weekly P significantly improved PFS, the primary endpoint, compared with P alone, and toxicity with P+A was manageable with A dose reduction. These data support further evaluation of alisertib in ER+ HER2- MBC pts.

Citation Format: Joyce O'Shaughnessy, Kristi McIntyre, Sharon Wilks, Ling Ma, William Fintel, Margaret Block, David Andorsky, Michael Danso, Nicholas Koutrelakos, Tracy Locke, Amy Scales, Lauren Steckel, Yunfei Wang. Randomized, multicenter phase II trial of weekly paclitaxel with or without the oral selective aurora kinase A (AURKA) inhibitor, Alisertib, in patients with ER+ HER2- metastatic breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD7-10.

Performance of a blood-based test for the detection of multiple cancer types

283

Background: Cancers of the esophagus, stomach, pancreas, gallbladder, liver, bile duct, colon and rectum will account for 17% of incident cancer diagnoses and 26% of cancer-related deaths in the US in 2019. We developed a methylation-based cfDNA early multi-cancer detection test that also can predict the tissue of origin (TOO) of these and other cancers types; performance of this test for gastrointestinal (GI) tract cancers is reported here. Methods: The Circulating Cell-free Genome Atlas (CCGA; NCT02889978) study is a prospective, multi-center, observational, case-control study with longitudinal follow-up, enrolling individuals with cancer ( > 20 cancers, all stages, newly diagnosed) and without cancer. Plasma cfDNA was subjected to a cross-validated targeted methylation (TM) sequencing assay. Methylation fragments were combined across targeted genomic regions and assigned a probability of cancer and a predicted TOO. GI cancer classes were upper GI (esophagus/stomach, n = 67), pancreas/gallbladder/extrahepatic bile duct (n = 95), liver/intrahepatic bile duct (n = 29), and colon/rectum (n = 121). Results: Detection across all GI cancers was 82% (95% CI 77-86) at a > 99% pre-set specificity. Overall predicted TOO accuracy was 92% (88-95) among the samples for which TOO was predicted (6/255 had indeterminate predicted TOO). The table shows performance by GI cancer type. Conclusions: Simultaneous detection at high specificity ( > 99%) of multiple cancer types, including GI cancers across stages at high sensitivity (82%), was shown using TM analysis of cfDNA. Accurate (92%) localization of cancers to specific regions of the GI tract was also achieved. Detection of multiple GI cancers from a single noninvasive blood test could be a practical method for detecting GI and other cancers, and may facilitate diagnostic work-ups. Clinical trial information: NCT02889978.

[Table: see text]

Plasma Collision in a Gas Atmosphere

We present a study on the impact of a gas atmosphere on the collision of two counterpropagating plasmas (gold and carbon). Imaging optical Thomson scattering data of the plasma collision with and without helium in between have been obtained at the Omega laser facility. Without gas, we observed large scale mixing of colliding gold and carbon ions. Once ambient helium is added, the two plasmas remain separated. The difference in ionic temperature is consistent with a reduction of the maximum Mach number of the flow from M=7 to M=4. It results in a reduction of a factor ∼10 of the counterstreaming ion-ion mean free path. By adding a low-density ambient gas, it is possible to control the collision of two high-velocity counterstreaming plasma, transitioning from an interpenetrating regime to a regime in agreement with a hydrodynamic description.

nab-Paclitaxel plus carboplatin or gemcitabine versus gemcitabine plus carboplatin as first-line treatment of patients with triple-negative metastatic breast cancer: results from the tnAcity trial

Background

Metastatic triple-negative breast cancer (mTNBC) has a poor prognosis and aggressive clinical course. tnAcity evaluated the efficacy and safety of first-line nab-paclitaxel plus carboplatin (nab-P/C), nab-paclitaxel plus gemcitabine (nab-P/G), and gemcitabine plus carboplatin (G/C) in patients with mTNBC.

Patients and methods

Patients with pathologically confirmed mTNBC and no prior chemotherapy for metastatic BC received (1 : 1 : 1) nab-P 125 mg/m2 plus C AUC 2, nab-P 125 mg/m2 plus G 1000 mg/m2, or G 1000 mg/m2 plus C AUC 2, all on days 1, 8 q3w. Phase II primary end point: investigator-assessed progression-free survival (PFS); secondary end points included overall response rate (ORR), overall survival (OS), percentage of patients initiating cycle 6 with doublet therapy, and safety.

Results

In total, 191 patients were enrolled (nab-P/C, n = 64; nab-P/G, n = 61; G/C, n = 66). PFS was significantly longer with nab-P/C versus nab-P/G [median, 8.3 versus 5.5 months; hazard ratio (HR), 0.59 [95% CI, 0.38-0.92]; P = 0.02] or G/C (median, 8.3 versus 6.0 months; HR, 0.58 [95% CI, 0.37-0.90]; P = 0.02). OS was numerically longer with nab-P/C versus nab-P/G (median, 16.8 versus 12.1 months; HR, 0.73 [95% CI, 0.47-1.13]; P = 0.16) or G/C (median, 16.8 versus 12.6 months; HR, 0.80 [95% CI, 0.52-1.22]; P = 0.29). ORR was 73%, 39%, and 44%, respectively. In the nab-P/C, nab-P/G, and G/C groups, 64%, 56%, and 50% of patients initiated cycle 6 with a doublet. Grade ≥3 adverse events were mainly hematologic.

Conclusions

First-line nab-P/C was active in mTNBC and resulted in a significantly longer PFS and improved risk/benefit profile versus nab-P/G or G/C.

Self-Generated Magnetic and Electric Fields at a Mach-6 Shock Front in a Low Density Helium Gas by Dual-Angle Proton Radiography

Shocks are abundant both in astrophysical and laboratory systems. While the electric fields generated at shock fronts have recently attracted great attention, the associated self-generated magnetic field is rarely studied, despite its ability to significantly affect the shock profile in the nonideal geometry where density and temperature gradients are not parallel. We report here the observation of a magnetic field at the front of a Mach ∼6 shock propagating in a low-density helium gas system. Proton radiography from different projection angles not only confirms the magnetic field's existence, but also provides a quantitative measurement of the field strength in the range ∼5 to 7 T. X-ray spectrometry allowed inference of the density and temperature at the shock front, constraining the plasma conditions under which the magnetic and electric fields are generated. Simulations with the particle-in-cell code lsp attribute the self-generation of the magnetic field to the Biermann battery effect (∇n_{e}×∇T_{e}).

Understanding palbociclib practice patterns in a real-world setting

200

Background: Real-world practice patterns often differ from treatment in clinical trials. We assessed real-world standard-of-care treatment with palbociclib (PAL) in the context of previously reported PALOMA trial results. Methods: POLARIS is a prospective, observational study of PAL in patients (pts) with hormone receptor–positive, human epidermal growth factor receptor 2–negative advanced breast cancer. Baseline demographics, clinical characteristics, initial treatment dose, dose modifications, dose delays, and adverse events (AEs) during the first 6 months (mo) of treatment were analyzed. Results: 412 pts enrolled at 92 US sites had at least 6 mo of PAL treatment; 73% received PAL in the first-line setting and 27% in second or later line. While a majority of pts received the recommended dose of 125 mg/d; 6% and 1% started at 100 mg and 75 mg, respectively. Physician-reported reasons for choosing a lower dose were: comorbidities (31%), pt age (21%), past treatment (10%), patient preference (3%), and other (34%). Selected pt and clinical characteristics, dosing, and treatment outcomes in POLARIS and in PALOMA-2 are shown in Table. Conclusions: In a real-world data set of 6 mo of PAL treatment, most pts started at the recommended dose, with tolerability and safety outcomes consistent with those reported in clinical trials. Differing populations, treatment patterns, and outcome reporting in real world vs trial settings underscore the need to study real-world practices and outcomes. Clinical trial information: NCT03280303

[Table: see text]

Health-related quality of life in patients receiving first-line eribulin mesylate with or without trastuzumab for locally recurrent or metastatic breast cancer

Background

Eribulin mesylate is a nontaxane microtubule dynamics inhibitor approved for second-line (European Union) or third-line (United States) treatment of metastatic breast cancer. Two phase 2 single trials, evaluating first-line eribulin as monotherapy (Study 206; NCT01268150) or in combination with trastuzumab (Study 208; NCT01269346) in locally recurrent or metastatic breast cancer, demonstrated objective response rates of 28.6 and 71.2%, respectively. Median progression-free survival was 6.8 and 11.6 months, respectively. Tolerability profiles were similar to those from previous studies. This secondary analysis was conducted to assess health-related quality of life (HRQoL) in both phase 2 trials.

Methods

Patients received eribulin mesylate 1.4 mg/m² intravenously on days 1 and 8 of each 21-day cycle. Patients in Study 208 also received intravenous trastuzumab on day 1 of each cycle (8 mg/kg in cycle 1, then 6 mg/kg). HRQoL was assessed by the European Organization for Research and Treatment of Cancer Quality-of-Life (QLQ-C30) assessment tool and the Quality-of-Life Questionnaire for Breast Cancer (QLQ-BR23) at baseline and cycles 2, 4, and 6. Results for clinically meaningful changes were based on previously published minimum important differences.

Results

Of the 108 patients (56 in Study 206 and 52 in Study 208) treated, 57 and 87%, respectively, completed 6 cycles. Completion rates for both questionnaires were 94 and 98%, respectively, at cycle 6. Most patients had stable/improved HRQoL scores with some exceptions; for example, more patients experienced a worsening in cognitive functioning and systemic therapy side effects than experienced improvement. Mean QLQ-C30 symptom scores correlated with corresponding adverse event rates for nausea/vomiting, dyspnea, appetite loss, constipation, and diarrhea in Study 206 and for fatigue, nausea/vomiting, pain, dyspnea, insomnia, constipation, and diarrhea in Study 208.

Conclusions

First-line eribulin ± trastuzumab therapy did not lead to deterioration of overall HRQoL in most patients, with more than 60% of patients having stable/improved global health status/quality-of-life scores. Eribulin has been demonstrated to be comparable with other chemotherapy agents with an acceptable safety profile. Therefore, further evaluation is warranted to determine whether eribulin ± trastuzumab therapy may be a potential option for first-line treatment in some patients with metastatic breast cancer who were recently treated in the neoadjuvant setting.

Trial registration

NCT01268150 (December 29, 2010), NCT01269346 (January 4, 2011)

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5674-5) contains supplementary material, which is available to authorized users.

Abstract PD5-08: Not presented

This abstract was not presented at the symposium.

Abstract PD3-14: Phase 1 study of the antibody-drug conjugate SGN-LIV1A in patients with heavily pretreated triple-negative metastatic breast cancer

Background

LIV-1, a transmembrane protein and downstream target of STAT3, is highly expressed in breast cancer cells. It is associated with lymph node involvement and metastatic progression. SGN-LIV1A is an anti-LIV-1 antibody conjugated via a protease-cleavable linker to monomethyl auristatin E (MMAE). Upon binding to cell-surface LIV-1, SGN-LIV1A is internalized and releases MMAE, which disrupts microtubulin and induces apoptosis.

Methods

This ongoing, phase 1 study evaluates safety, tolerability, pharmacokinetics, and antitumor activity of SGN-LIV1A (q3wks IV) in women with LIV-1-positive, unresectable, locally advanced or metastatic breast cancer (LA/MBC) (NCT01969643). Patients (pts) with measurable disease and ≥2 prior cytotoxic regimens for LA/MBC are eligible. Pts with ≥ Grade 2 neuropathy are excluded. Response is assessed per RECIST v1.1; pts with stable disease (SD) or better can continue treatment until disease progression or intolerable toxicity. At completion of dose escalation in hormone receptor-positive/HER2-negative (HR+/HER2–) and triple-negative (TN) pts, expansion cohorts were opened to further evaluate safety and antitumor activity of monotherapy in TN pts. Tumor biopsies are evaluated for LIV-1 expression.

Results

To date, 69 pts (18 HR+/HER2–, 51 TN) have received a median of 3 cycles (range, 1–12) of SGN-LIV1A at doses of 0.5–2.8 mg/kg. Median age was 56 yrs. Pts had a median of 3 prior cytotoxic regimens for LA/MBC; 58 had visceral disease and 37 had bone metastases. No dose-limiting toxicities (DLTs) occurred in 19 DLT-evaluable pts; maximum tolerated dose was not exceeded at 2.8 mg/kg. Expansion cohorts of TN pts were opened at 2.0 and 2.5 mg/kg. Treatment-emergent adverse events (AEs) reported in ≥25% of pts were fatigue (59%), nausea (51%), peripheral neuropathy (44%), alopecia (36%), decreased appetite (33%), constipation (30%), abdominal pain, diarrhea, and neutropenia (25% each). Most AEs were Grade 1/2; AEs ≥ Grade 3 included neutropenia (25%) and anemia (15%). Febrile neutropenia occurred in 2 pts whose total dose exceeded 200 mg per cycle, including 1 treatment-related death due to sepsis. No other treatment-related deaths occurred on-study. Seven pts discontinued treatment due to AEs. In dose escalation, activity was observed in 17 efficacy evaluable (EE) HR+/HER2- pts, with a disease control rate (DCR= CR+PR+SD) of 59% (10 SD), including 1 pt with SD ≥24 wks. Among the 44 EE TN pts (dose escalation plus expansion cohorts), the objective response rate (ORR) was 32% (14 PR) with a confirmed PR rate of 21%, DCR was 64% (14 PR, 14 SD), and clinical benefit rate (CBR=CR+PR+SD ≥24 wks) was 36% (16 pts). For TN pts, median PFS was 11.3 wks (95% CI: 6.1, 17.1); 10 pts remain on treatment.

Of 631 MBC tumor samples of all clinical subtypes evaluated for LIV-1, 91% were positive; 75% had moderate-to-high expression (H-score ≥100).

Conclusions

LIV-1 is expressed in almost all MBC tumors. SGN-LIV1A monotherapy was generally well tolerated and showed encouraging antitumor activity in heavily pretreated TN MBC, with a PR rate of 32%, confirmed PR rate of 21%, and CBR (≥24 wks) of 36%. Response duration data continue to evolve. Enrollment continues in the TN monotherapy expansion cohort.

Citation Format: Modi S, Pusztai L, Forero A, Mita M, Miller KD, Weise A, Krop I, Burris III H, Kalinsky K, Tsai M, Liu MC, Hurvitz SA, Wilks S, Ademuyiwa F, Diab S, Han HS, Kato G, Nanda R, O'Shaughnessy J, Kostic A, Li M, Specht J. Phase 1 study of the antibody-drug conjugate SGN-LIV1A in patients with heavily pretreated triple-negative metastatic breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-14.

Abstract OT3-05-03: POLARIS: Palbociclib (P) in hormone receptor-positive (HR+) advanced breast cancer: A prospective multicenter noninterventional study

Background: P is a novel cyclin-dependent kinase 4/6 inhibitor approved in the United States and Canada in combination with endocrine therapy for HR+/human epidermal growth factor receptor 2–negative (HER2-) advanced breast cancer (ABC). Despite promising trial results, not all patients respond to P. Moreover, despite a median age at diagnosis of 62 years, elderly patients are underrepresented in targeted therapy trials, including the PALOMA studies assessing P. It is important to understand P use in real-world practice settings, including tolerability and outcomes in the vulnerable older population. In addition, understanding the mechanisms of P response or resistance is critical to identify clinical factors and biomarkers that can predict which patients will benefit from P. This multicenter observational and biomarker study will seek to address these and other data gaps.

Trial Design: This is a prospective, noninterventional study of 1500 patients treated with P from 100 US and 10 Canadian sites. Study duration will span 2 years of recruitment and 3 years of follow-up after P treatment, until patient withdrawal from the study or death. Study participation is not intended to alter routine treatment; all treatment decisions, including type and timing of disease monitoring, are at the discretion of the treating physician and patient.

Eligibility: Eligible patients are aged ≥18 years with a diagnosis of adenocarcinoma of the breast with (1) evidence of advanced or metastatic disease not amenable to treatment with curative intent, (2) documented HR+/HER2- status, and (3) planned treatment with P. Patients with a life expectancy &lt;3 months at initial diagnosis, those participating in interventional trials, and those receiving active treatment for malignancies other than ABC at enrollment are ineligible.

Aims: In a large real-world cohort of HR+/HER2- ABC patients treated with P in routine clinical practice, this study aims to assess the following: prescribing and treatment patterns for ABC before, during, and after P therapy; overall clinical response to P; biomarker assessment investigating potential mechanisms of response and resistance to P based on genomic analyses of blood samples; patient quality of life, as measured by the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Core 30; geriatric assessments in patients aged ≥70 years at enrollment based on the G8 Geriatric Screening Tool and the Activities of Daily Living questionnaire; and sequencing of treatment for metastatic disease. Other outcomes to be assessed include survival and toxicity.

Methods: Data will be collected from routine clinical assessments. Patients will have the option to provide blood samples drawn at standard-of-care intervals at baseline, during P treatment, and at the end of treatment for potential biomarker identification. Analyses will be primarily descriptive, with point estimates and confidence intervals as well as Kaplan-Meier methods used to assess time-to-event outcomes.

Accrual: Presently, 46 patients from 20 sites are enrolled.

Funding: Pfizer Inc.

Citation Format: Tripathy D, Bardia A, Blum JL, Rocque G, Wilks S, Lakhanpal S, Migas J, Cappelleri J, Perkins J, Comstock G, Wang Y. POLARIS: Palbociclib (P) in hormone receptor-positive (HR+) advanced breast cancer: A prospective multicenter noninterventional study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-05-03.

APF530 versus ondansetron, each in a guideline-recommended three-drug regimen, for the prevention of chemotherapy-induced nausea and vomiting due to anthracycline plus cyclophosphamide-based highly emetogenic chemotherapy regimens: a post hoc subgroup analysis of the Phase III randomized MAGIC trial

BACKGROUND

APF530, a novel extended-release granisetron injection, was superior to ondansetron in a guideline-recommended three-drug regimen in preventing delayed-phase chemotherapy-induced nausea and vomiting (CINV) among patients receiving highly emetogenic chemotherapy (HEC) in the double-blind Phase III Modified Absorption of Granisetron In the prevention of CINV (MAGIC) trial.

PATIENTS AND METHODS

This MAGIC post hoc analysis evaluated CINV prevention efficacy and safety of APF530 versus ondansetron, each with fosaprepitant and dexamethasone, in patient subgroup receiving an anthracycline plus cyclophosphamide (AC) regimen. Patients were randomized 1:1 to APF530 500 mg subcutaneously (granisetron 10 mg) or ondansetron 0.15 mg/kg intravenously (IV) (≤16 mg); stratification was by planned cisplatin ≥50 mg/m² (yes/no). Patients were to receive fosaprepitant 150 mg IV and dexamethasone 12 mg IV on day 1, then dexamethasone 8 mg orally once daily on day 2 and twice daily on days 3 and 4. Patients were mostly younger females (APF530 arm, mean age 54.1 years, female, 99.3%; ondansetron arm, 53.8 years, female 98.3%). The primary end point was delayed-phase (>24-120 hours) complete response (CR).

RESULTS

APF530 versus ondansetron regimens achieved numerically better CINV control in delayed and overall (0-120 hours) phases for CR, complete control, total response, rescue medication use, and proportion with no nausea. APF530 trends are consistent with the overall population, although not statistically superior given the underpowered AC subgroup analysis. The APF530 regimen in this population was generally well tolerated, with safety comparable to that of the overall population.

CONCLUSION

APF530 plus fosaprepitant and dexamethasone effectively prevented CINV among patients receiving AC-based HEC, a large subgroup in whom CINV control has traditionally been challenging.

Transition from Collisional to Collisionless Regimes in Interpenetrating Plasma Flows on the National Ignition Facility

A study of the transition from collisional to collisionless plasma flows has been carried out at the National Ignition Facility using high Mach number (M>4) counterstreaming plasmas. In these experiments, CD-CD and CD-CH planar foils separated by 6-10 mm are irradiated with laser energies of 250 kJ per foil, generating ∼1000  km/s plasma flows. Varying the foil separation distance scales the ion density and average bulk velocity and, therefore, the ion-ion Coulomb mean free path, at the interaction region at the midplane. The characteristics of the flow interaction have been inferred from the neutrons and protons generated by deuteron-deuteron interactions and by x-ray emission from the hot, interpenetrating, and interacting plasmas. A localized burst of neutrons and bright x-ray emission near the midpoint of the counterstreaming flows was observed, suggesting strong heating and the initial stages of shock formation. As the separation of the CD-CH foils increases we observe enhanced neutron production compared to particle-in-cell simulations that include Coulomb collisions, but do not include collective collisionless plasma instabilities. The observed plasma heating and enhanced neutron production is consistent with the initial stages of collisionless shock formation, mediated by the Weibel filamentation instability.

Abstract P6-12-15: Efficacy results of a phase 1/2 study of glucocorticoid receptor (GR) antagonist mifepristone (MIFE) in combination with eribulin in GR-positive triple-negative breast cancer (TNBC)

Background: GR is variably expressed in TNBC and high expression is associated with poor prognosis in estrogen receptor-negative (ER-) early stage breast cancer. Treatment with mifepristone (MIFE) potentiates the effectiveness of chemotherapy in GR+ TNBC xenografts. Enrollment is complete in this study of patients with GR+ TNBC treated at the recommended Phase 2 dose (RP2D) of MIFE in combination with eribulin. Objectives: To determine the safety, tolerability, pharmacokinetics (PK) and clinical activity of the MIFE plus eribulin combination in pts with GR+ TNBC at the RP2D. Methods: Eligibility: In Part 1 (dose finding), pts with solid tumors; in Part 2 (expansion phase), pts with TNBC (GR result required at time of screening in Part 1, but could be pending at time of screening in Part 2). Up to 5 prior chemotherapy regimens for advanced disease; ECOG PS 0-1; adequate end-organ function. Design: 3 + 3 dose escalation scheme. After a 7-day lead-in of oral daily MIFE alone, MIFE was continued daily and eribulin was given on days 1 and 8 of a 21-day cycle. GR+ was defined as &gt;10% of tumor cells with any intensity of GR staining. Results: 16 pts with metastatic breast cancer were treated in Part 1, and 21 pts with TNBC were treated in Part 2. Median age was 54 (range 30-81). MTD/RP2D was MIFE 300 mg/day + eribulin 1.1 mg/m2. Safety: DLT in Part 1 was neutropenia. Neutropenia occurred in 23/36 total patients (2 Grade [G] 1, 10 G3, 11 G4); 2 instances included neutropenic fever. Recovery of WBC was brisk with growth factor support. Neuropathy was observed in 8 pts (5 G1, 1 G2, 2 G3). Other most common AEs (fatigue, hypokalemia, nausea, alopecia) were mainly G1 or G2; among these, G3/G4 events were limited to fatigue (4 G3), hypokalemia (3 G3 and 1 G4) and nausea (1 G3). There were 2 instances of G1 vaginal bleeding. There was no impact of MIFE on eribulin PK. Efficacy: There were 23 evaluable pts with TNBC across Parts 1 and 2 treated at the RP2D: 21 GR+, 2 GR status unknown; median of 3 prior chemotherapy regimens; 1 patient had received prior eribulin. Responses were: 3 PR, 8 SD, 11 PD and one too early to assess. Median PFS was 9 weeks. Conclusions: MIFE plus eribulin was well tolerated and appears to be an active treatment regimen. Five TNBC patients had a PFS longer than the upper 95% CI for PFS (i.e., &gt;15 wks) reported by Aogi et al. for TNBC treated with eribulin (Annals of Oncology 2012?23:144148). Clinical trial information: NCT02014337.

Citation Format: Han HS, Wilks S, Paplomata E, Modiano MR, Becerra C, Braiteh FS, Spira AI, Pluard TJ, Richards DA, Conzen SD, Baker G, Fishman RS, Marcantonio A, O'Shaughnessy J, Nanda R. Efficacy results of a phase 1/2 study of glucocorticoid receptor (GR) antagonist mifepristone (MIFE) in combination with eribulin in GR-positive triple-negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-15.

Clinical effects of prior trastuzumab on combination eribulin mesylate plus trastuzumab as first-line treatment for human epidermal growth factor receptor 2 positive locally recurrent or metastatic breast cancer: results from a Phase II, single-arm, multicenter study

Eribulin mesylate, a novel nontaxane microtubule dynamics inhibitor in the halichondrin class of antineoplastic drugs, is indicated for the treatment of patients with metastatic breast cancer who previously received ≥2 chemotherapy regimens in the metastatic setting. Primary data from a Phase II trial for the first-line combination of eribulin plus trastuzumab in human epidermal growth factor receptor 2 positive patients showed a 71% objective response rate and tolerability consistent with the known profile of these agents. Here, we present prespecified analyses of efficacy of this combination based on prior trastuzumab use. Patients received eribulin mesylate 1.4 mg/m² (equivalent to 1.23 mg/m² eribulin [expressed as free base]) intravenously on days 1 and 8 plus trastuzumab (8 mg/kg intravenously/cycle 1, then 6 mg/kg) on day 1 of each 21-day cycle. Objective response rates, progression-free survival, and tolerability were assessed in patients who had and had not received prior adjuvant or neoadjuvant (neo/adjuvant) trastuzumab treatment. Fifty-two patients (median age: 59.5 years) received eribulin/trastuzumab for a median treatment duration of ~31 weeks; 40.4% (n=21) had been previously treated with neo/adjuvant trastuzumab prior to treatment with eribulin plus trastuzumab for metastatic disease (median time between neo/adjuvant and study treatment: 23 months). In trastuzumab-naïve patients (n=31) compared with those who had received prior trastuzumab, objective response rate was 77.4% versus 61.9%, respectively; duration of response was 11.8 versus 9.5 months, respectively; clinical benefit rate was 87.1% versus 81.0%, respectively; and median progression-free survival was 12.2 versus 11.5 months, respectively. The most common grade 3/4 treatment-emergent adverse events (occuring in ≥5% of patients) in patients who received prior trastuzumab versus trastuzumab naïve patients, respectively, were neutropenia (47.6% vs 32.3%), peripheral neuropathy (14.3% vs 25.8%), febrile neutropenia (14.3% vs 3.2%), fatigue (9.5% vs 6.5%), nausea (9.5% vs 0%), vomiting (9.5% vs 3.2%), and leukopenia (9.5% vs 3.2%). In patients with human epidermal growth factor receptor 2 positive metastatic breast cancer, first-line eribulin/trastuzumab treatment demonstrated substantial antitumor activity and was well tolerated, regardless of prior neo/adjuvant trastuzumab treatment.

PD-L1 Expression by Two Complementary Diagnostic Assays and mRNA In Situ Hybridization in Small Cell Lung Cancer

INTRODUCTION

Therapeutic antibodies to immune checkpoints show promising results. Programmed death-ligand 1 (PD-L1), an immune checkpoint ligand, blocks the cancer immunity cycle by binding the PD-L1 receptor (programmed death 1). We investigated PD-L1 protein expression and messenger RNA (mRNA) levels in SCLC.

METHODS

PD-L1 protein expression and mRNA levels were determined by immunohistochemistry (IHC) with SP142 and Dako 28-8 PD-L1 antibodies and in situ hybridization in primary tumor tissue microarrays in both tumor cells and tumor-infiltrating immune cells (TIICs) obtained from a limited-disease SCLC cohort of 98 patients. An additional cohort of 96 tumor specimens from patients with extensive-disease SCLC was assessed for PD-L1 protein expression in tumor cells with Dako 28-8 antibody only.

RESULTS

The overall prevalence of PD-L1 protein expression in tumor cells was 16.5%. In the limited-disease cohort, the prevalences of PD-L1 protein expression in tumor cells with SP142 and Dako 28-8 were 14.7% and 19.4% (tumor proportion score cutoff ≥1%) and PD-L1 mRNA ISH expression was positive in 15.5% of tumor samples. Increased PD-L1 protein/mRNA expression was associated with the presence of more TIICs (p < 0.05). The extensive-disease cohort demonstrated a 14.9% positivity of PD-L1 protein expression in tumor cells with Dako 28-8 antibody.

CONCLUSIONS

A subset of SCLCs is characterized by positive PD-L1 and/or mRNA expression in tumor cells. Higher PD-L1 and mRNA expression correlate with more infiltration of TIICs. The prevalence of PD-L1 in SCLC is lower than that published for NSCLC. The predictive role of PD-L1 expression in SCLC treatment remains to be established.

Abstract 4159: Characterization of the T-cell receptor (TCR) repertoire in extensive disease small cell lung cancer (ED SCLC)

Background: The current study explores T-cell (TC) clonality and molecular factors associated with this metric. Tumors employ multiple mechanisms to evade antitumor immune responses. One process involves TC inhibition via upregulation of immune checkpoint (IC) ligands in the tumor microenvironment (TME). Gradual upregulation of inhibitory receptor at their cellular surface results in a decreased capacity to proliferate and activate cytotoxic pathways against tumor cells presenting antigenic peptides.1 In melanoma, this subset of exhausted TCs has been described as highly clonal, where the majority of PD-1-expressing TC population shares the same TCR sequence specific against the same antigenic fragment.2 Previous studies have demonstrated that a clonal TCR repertoire appears to be associated in part with therapeutic responses during IC blockade.3

Methods: We performed TCR sequencing on 82 blood and 73 archival tumor tissue samples collected from ED SCLC patients (pts) in an ongoing longitudinal cohort study in US community oncology practices. Of these, 82 blood and 48 tissue samples had sufficient material available to quantify a clonality metric. To quantify TC abundance as a fraction of total nucleated cells, 82 blood and 58 tissue samples had sufficient material available.

Results: Within the subset of 48 tumor samples, a more clonal (ie, less diverse) TCR repertoire was associated with less necrosis (P≤0.012) and lower levels of inflammatory cell infiltration in the local TME (P≤0.021). When pts were divided into 2 equal groups according to the median clonality level, pts with a less clonal TCR repertoire (n = 24/48) who were treated with non-immune-targeted therapy trended toward a longer overall survival (OS; 446 vs 301 days; P≤0.039). In contrast, the percentage of TCs in the TME did not correlate with improved survival (P≤0.412), necrosis (P≤0.131), and inflammation (P≤0.615). This observation differs from results in melanoma describing the impact of IC blockade where pts responding to therapy were associated with a more clonal TME TC population and increased CD8 TCs in the tumor compartment and at the invasive margin.3 In blood, while a less clonal TCR repertoire was associated with a similar but non-significant trend toward longer survival (P≤0.148), pts with increased TC abundance had longer OS (P≤0.025). No association was observed between clonality in TME and clonality (P≤0.571) or TC abundance (P≤0.965) in blood.

Conclusion: We hypothesize that a diverse TCR repertoire in the TME and increased peripheral TC abundance are 2 predictors of longer OS in ED SCLC. To further explore factors that may influence TC responses in ED SCLC, the current TCR sequencing results will be integrated with transcriptome and whole genome sequencing analyses.

References

1. Wherry EJ. Nat Immunol. 2011;12:492-99.

2. Gros A, et al. J Clin Invest. 2014;124:2246-59.

3. Tumeh PC, et al. Nature. 2014;515:568-71.

Citation Format: Maen Hussein, Sharon Wilks, Marc Monte, Donald A. Richards, Jerome H. Goldschmidt, David Waterhouse, Lisu Wang, Saumya Pant, Erik Yusko, Ryan O. Emerson, Darin M. Taverna, Kaushal Desai, Spyro Mousses, Zhenhao Qi, Jason D. Hipp, Harlan Robins, Kimary Kulig, Cory Batenchuk. Characterization of the T-cell receptor (TCR) repertoire in extensive disease small cell lung cancer (ED SCLC). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4159.

Molecular Alterations and Everolimus Efficacy in Human Epidermal Growth Factor Receptor 2-Overexpressing Metastatic Breast Cancers: Combined Exploratory Biomarker Analysis From BOLERO-1 and BOLERO-3

PURPOSE

Two recent phase III trials, BOLERO-1 and BOLERO-3 (Breast Cancer Trials of Oral Everolimus), evaluated the addition of everolimus to trastuzumab and chemotherapy in human epidermal growth factor receptor 2-overexpressing advanced breast cancer. The current analysis aimed to identify biomarkers to predict the clinical efficacy of everolimus treatment.

METHODS

Archival tumor samples from patients in BOLERO-1 and BOLERO-3 were analyzed using next-generation sequencing, immunohistochemistry, and Sanger sequencing.

RESULTS

Biomarker data were available for 549 patients. PIK3CA activating mutations and PTEN loss were reported in 30% and 16% of BOLERO-1 samples and in 32% and 12% of BOLERO-3 samples, respectively. PI3K pathway was hyperactive (PIK3CA mutations and/or PTEN loss and/or AKT1 mutation) in 47% of BOLERO-1 and 41% of BOLERO-3 samples. In both studies, differential progression-free survival (PFS) benefits of everolimus were consistently observed in patient subgroups defined by their PI3K pathway status. When analyzing combined data sets of both studies, everolimus was associated with a decreased hazard of progression in patients with PIK3CA mutations (hazard ratio [HR], 0.67; 95% CI, 0.45 to 1.00), PTEN loss (HR, 0.54; 95% CI, 0.31 to 0.96), or hyperactive PI3K pathway (HR, 0.67; 95% CI, 0.48 to 0.93). Patients with wild-type PIK3CA (HR, 1.10; 95% CI, 0.83 to 1.46), normal PTEN (HR, 1.00; 95% CI, 0.80 to 1.26), or normal PI3K pathway activity (HR, 1.19; 95% CI, 0.87 to 1.62) did not derive PFS benefit from everolimus.

CONCLUSION

This analysis, although exploratory, suggests that patients with human epidermal growth factor receptor 2-positive advanced breast cancer having tumors with PIK3CA mutations, PTEN loss, or hyperactive PI3K pathway could derive PFS benefit from everolimus.

Abstract P1-10-07: Phase 3 comparison of APF530 versus ondansetron, each in a guideline-recommended 3-drug regimen for prevention of chemotherapy-induced nausea and vomiting due to anthracycline + cyclophosphamide (AC)–based highly emetogenic chemotherapy (HEC) regimens: A post hoc subgroup analysis of the MAGIC trial

Background:Managing delayed chemotherapy-induced nausea and vomiting (CINV) associated with HEC is an unmet need. AC-based HEC is often administered to breast cancer patients (pts), a mostly female, high-CINV-risk population. APF530, an extended-release formulation of granisetron, demonstrated superior complete response (CR; no emesis [vomiting, retching] + no rescue medication use) in delayed-phase (&gt;24-120 h) CINV with HEC (ASCO criteria) vs ondansetron (Ond) (65% vs 57%, P=0.014), each combined with a neurokinin-1 antagonist and dexamethasone (Dex) (NCT02106494). This post hoc analysis evaluated efficacy and safety of APF530 in pts receiving AC-based therapy.

Methods: In this randomized, double-blind, multicenter trial, pts scheduled to receive single-day HEC were stratified by cisplatin ≥50 mg/m2 yes/no and randomized 1:1 to APF530 500 mg SC (granisetron 10 mg) or Ond 0.15 mg/kg IV. Pts received concomitant Dex 12 mg IV and fosaprepitant 150 mg IV on day 1 and oral Dex on days 2-4. The primary end point was CR in the delayed phase. Secondary and other end points included CR in acute (0-24 h) and overall (0-120 h) phases, and complete control (CC; CR and no more than mild nausea) and total response (TR; CR and no nausea) in acute, delayed, and overall phases. Rates were compared using 95% confidence intervals (CIs) for treatment differences; post hoc analysis was not powered to detect treatment differences in the AC subgroup. Safety assessments included adverse events (AEs), injection-site reactions (ISRs), laboratory parameters, and vital signs.

Results: A total of 589/902 pts (65%) in the modified intent-to-treat population received AC-based HEC (APF530 291, Ond 298). Baseline demographics were balanced between treatment arms. The majority of pts in the AC subgroup were female (APF530 99%, Ond 98%). Delayed-phase CR was higher with APF530 vs Ond, approaching statistical significance (APF530 64%, Ond 56%; P=0.062) in the AC subgroup, similar to the benefit seen in the larger study. No appreciable benefit of APF530 vs Ond was observed in the acute phase, and trends favorable to APF530 were observed in the overall phase (Table). APF530 was well tolerated. Most AEs were ISRs, generally mild or moderate, and resolved by end of study.

Phase, n (%)APF530OndansetronTreatment DifferenceN=291N=298(95% CI), %Complete responseDelayed185 (64)167 (56)8 (-0.4, 15.4)Overall163 (56)153 (51)5 (-3.4, 12.7)Acute205 (70)204 (69)1 (-5.4, 9.4)Complete controlDelayed171 (59)156 (52)7 (-1.6, 14.4)Overall149 (51)143 (48)3 (-4.9, 11.3 )Acute193 (66)191 (64)2 (-5.5, 9.9)Total responseDelayed119 (41)107 (36)5 (-2.9, 12.8)Overall100 (34)94 (32)2 (-4.8, 10.4)Acute164 (56)173 (58)-2 (-9.7, 6.3)

Conclusions: APF530 demonstrated an apparent clinical benefit in delayed-phase CR in pts receiving AC-based HEC, concordant with the statistically significant benefit seen in the overall study population. Prevention of CINV in this patient population continues to be a treatment challenge and further investigation is needed.

Citation Format: Schnadig I, Agajanian R, Dakhil S, Taylor C, Wilks S, Cooper W, Mosier M, Payne Y, Klepper M, Vacirca J. Phase 3 comparison of APF530 versus ondansetron, each in a guideline-recommended 3-drug regimen for prevention of chemotherapy-induced nausea and vomiting due to anthracycline + cyclophosphamide (AC)–based highly emetogenic chemotherapy (HEC) regimens: A post hoc subgroup analysis of the MAGIC trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-10-07.

Abstract P6-13-21: Phase 1 study of GR antagonist mifepristone (M) in combination with eribulin (E) in advanced solid tumors, with dose expansion in patients (pts) with GR-positive triple-negative breast cancer (TNBC)

Background: High tumor GR expression is associated with poor prognosis in estrogen receptor (ER) negative early-stage breast cancer. Co-treatment with M, a GR antagonist, potentiates effects of chemotherapy in ER- breast cancer xenograft studies. Herein we describe results of a phase 1 dose-escalation study of M plus E, with an ongoing dose expansion cohort in pts with GR+ TNBC.

Objectives: Determine 1) safety and tolerability, 2) recommended phase 2 dose (RP2D) of M + E, and 3) characterize pharmacokinetics (PK) and clinical activity of M in pts with GR+ TNBC.

Methods: Eligibility: 1) relapsed/refractory breast, ovarian, prostate, urothelial, sarcoma, or non-small cell lung cancer; 2) 2-5 prior chemotherapy regimens for advanced disease; 3) ECOG PS 0-1; and 4) adequate end-organ function. Study used a 3 + 3 dose escalation scheme. After a 7 day lead-in of M alone, M was administered by mouth daily in combination with E given IV on days 1 and 8 of a 21 day cycle.

Results: 13 pts in Part 1 Dose escalation with metastatic breast cancer (MBC) were treated with M+E: 5 TNBC, 8 GR+ tumors, 2 GR- tumors, and 3 of unknown GR status. Pts were treated at 3 dose levels (DL)[M mg/d, E mg/m2]: 3 at DL1 [600, 1.1] 4 at DL-1a [300, 1.4], and 6 at DL-1 [300, 1.1]. Median duration of treatment was 90+ days. Neutropenia leading to delay of E was dose limiting in 4 pts. CTAE Grade 3/4 neutropenia was observed in 10 pts over all DL, but easily managed (9 pts with growth factor support). Other grade 3+ toxicities were neuropathy (2 pts) and onycholysis (1 pt). No other significant toxicity was noted.

RP2D was determined as 300mg/d M and 1.1mg/m2 E. At this DL there were no DLTs. PK of M and E were as predicted from published literature with no evidence of drug-drug interaction (DDI). A total of 6 pts received this dose (3 TNBC; 3 MBC). All 3 TNBC were GR+. 1 had partial response, 1 had stable disease, and 1 had progressive disease.

A phase I/II study of M+E is now in progress. To date, 3 GR+ TNBC pts have been treated for a median of 28+ days.

Conclusion: M + E is a novel combination designed to improve antitumor activity. It is well tolerated with evidence of clinical activity and no evidence of DDI. RP2D is 300mg M + E 1.1mg/m2. Study is ongoing in expansion phase where recruitment is limited to pts with GR+ TNBC. Additional PK and clinical data will be presented.

Citation Format: Wilks S, Modiano M, Spira A, Becerra C, Walling J, Nguyen D, Baker G, Conzen SD, Nanda R. Phase 1 study of GR antagonist mifepristone (M) in combination with eribulin (E) in advanced solid tumors, with dose expansion in patients (pts) with GR-positive triple-negative breast cancer (TNBC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-13-21.

Case Studies in the Management of Metastatic Breast Cancer with Eribulin

Outcomes for triple-negative or hormone-refractory metastatic breast cancer (MBC) are poor and treatment options are limited. Described herein are cases of two women who developed MBC following adjuvant chemotherapy and endocrine therapy for human epidermal growth factor receptor 2 (HER2)-negative ductal carcinoma. Both underwent treatment with fulvestrant, followed by paclitaxel and letrozole or nab-paclitaxel. Following disease progression, both patients started single-agent eribulin mesylate (1.4 mg/m² on Days 1 and 8 of a 21-day cycle). The first patient is currently continuing on eribulin at full dose, despite interruption for hip surgery and the presence of grade 1 neuropathy in the hands and feet. The second patient had a partial response with eribulin, which was sustained for 4 months. She was able to tolerate the full dose of eribulin despite slight worsening of the neuropathy that was present at baseline. Eribulin may be a beneficial option for hormone-refractory MBC with extensive treatment experience.

Phase III study of APF530 versus ondansetron with a neurokinin 1 antagonist + corticosteroid in preventing highly emetogenic chemotherapy-induced nausea and vomiting: MAGIC trial

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Background: Managing chemotherapy-induced nausea and vomiting (CINV) associated with delayed ( > 24-120 h) highly emetogenic chemotherapy (HEC) is an unmet need. APF530, extended-release granisetron, provides sustained release over ≥ 5 days to prevent acute (0-24 h) and delayed CINV. This trial compared the efficacy and safety of APF530 in preventing CINV after HEC in a 3-drug regimen vs a standard 3-drug regimen with ondansetron (Ond). Methods: In this double-blind, multicenter study (NCT02106494), patients (pts) receiving single-day HEC (2011 ASCO guidelines) were randomized 1:1 to APF530 500 mg SC (10 mg granisetron) or Ond 0.15 mg/kg IV and stratified by cisplatin ( ≥ 50 mg/m2, yes/no). Pts were scheduled to receive concomitant dexamethasone (Dex) 12 mg IV + fosaprepitant (Fos) 150 mg IV on day 1 + PO Dex on days 2-4. The primary end point was delayed-phase complete response (CR) (no emesis, no rescue medication). Secondary end points included CR in acute and overall phases and complete control (CC; CR and no more than mild nausea) in acute, delayed, and overall phases. Treatment (tx) comparisons used chi-square test controlling for cisplatin. Adverse events (AEs) and injection-site reactions (ISRs) were assessed. Results: Modified intent-to-treat analysis included 902 pts (APF530, n = 450; Ond, n = 452) with baseline demographics balanced between tx groups. A significantly higher % of APF530 (65%) vs Ond (57%) pts had delayed-phase CR (P= .014). A significantly higher % of APF530 (61%) vs Ond (53%) pts had delayed-phase CC (P= .022, Table). CR and CC rates in acute and overall phases were numerically higher with APF530 vs Ond, but not statistically significant. APF530 was well tolerated. Most common AEs were ISRs, mostly mild or moderate. Conclusions: APF530 with Fos+Dex led to statistically higher CR and CC rates in delayed-phase CINV with HEC vs a standard 3-drug regimen of Ond with Fos+Dex. Clinical trial information: NCT02106494. [Table: see text]

Impact of prior anthracycline or taxane use on eribulin effectiveness as first-line treatment for metastatic breast cancer: results from two phase 2, multicenter, single-arm studies

Eribulin mesylate has efficacy in patients who have received ≥2 prior chemotherapies for metastatic breast cancer (MBC) including an anthracycline and taxane. Phase 2 trials showed clinical activity and acceptable tolerability of first-line eribulin (HER2− MBC; Study 206) and eribulin plus trastuzumab (HER2+ MBC; Study 208). Prespecified analyses evaluated efficacy by prior anthracycline and/or taxane use. Patients received eribulin mesylate (1.4 mg/m² IV; Days 1 and 8) and, in Study 208, trastuzumab (8 mg/kg IV/Cycle 1, then 6 mg/kg; Day 1) in 21-day cycles. Endpoints included objective response rate (ORR), progression-free survival (PFS), and tolerability. In Study 206 (N = 56), 48 % of patients had received prior anthracycline, 46 % prior taxane, 36 % prior anthracycline and taxane, and 41 % were chemotherapy-naïve. In Study 208 (N = 52), these percentages were 21, 44, 17, and 52 %, respectively. In Study 206, ORR and median PFS were similar for anthracycline-pretreated (25.9 %, 5.8 months), taxane-pretreated (26.9 %, 5.8 months), anthracycline- and taxane-pretreated (25.0 %, 6.7 months), and anthracycline/taxane-naïve patients (30.4 %, 7.6 months). In Study 208, ORR/median PFS were 63.6 %/6.7 months among anthracycline-pretreated patients, 56.5 %/6.8 months among taxane-pretreated patients, 55.6 %/5.9 months among anthracycline- and taxane-pretreated patients, and 81.5 %/13.1 months among anthracycline/taxane-naïve patients. Tolerability was generally similar among subgroups. In these studies, first-line eribulin in HER2− MBC and eribulin/trastuzumab in HER2+ MBC was effective with acceptable tolerability, regardless of prior anthracycline/taxane treatment. Prior chemotherapy was associated with lower ORR and shorter PFS with eribulin/trastuzumab in HER2+ MBC but not with eribulin in HER2− MBC.

Abstract P5-17-03: Quality of life results from a phase 2, multicenter, single-arm study of eribulin mesylate plus trastuzumab as first-line therapy for locally recurrent or metastatic HER2+ breast cancer

Introduction: Eribulin mesylate is a nontaxane microtubule dynamics inhibitor that has showed an overall survival benefit relative to other commonly used agents in patients with ≥2 prior MBC therapies. Primary data from a phase 2 trial for first-line eribulin + trastuzumab [TRAS] in HER2+ patients with MBC showed an objective response rate of 71%, clinical benefit rate of 84.6%, disease control rate of 96.2%, PFS of 11.6 months, and tolerability similar to known profiles for these agents. Here, we present prespecified QoL, efficacy, and safety/tolerability results.

Methods: Patients received eribulin mesylate 1.4 mg/m2 IV on days 1 and 8 of each 21-day cycle and initial TRAS (8 mg/kg IV/day 1), followed by 6 mg/kg on day 1 of each subsequent cycle. Response, PFS, QoL as measured by EORTC QoL assessment tool (QLQ-C30) and QLQ-BR23, and tolerability were assessed. Percentage of patients with at least ±10-point change from baseline was calculated at each visit. Time to deterioration was defined as time from first dose to worsening in QoL score that reached minimally clinically important difference (MID) (ie, 10 points in global health status [GHS] in QLQ-C30) without further improvement of at least MID; this was estimated overall and by response status.

Results: At cycle 6 (n=44; completion rate=84.6% of 52 patients enrolled), more patients fell in the stable category (within +/-10 points change from baseline), except for pain (47.7% with improvement), cognitive functioning (45.5% worsening), fatigue and systemic therapy side effects (50% worsening for each), and arm symptoms (47.7% improvement) (Table). Median times to deterioration for GHS/QoL were 7.6 months overall (n=51), and 7.6 and 7.0 months for responders (n=36) and nonresponders (n=15), respectively (HR 0.73; 95% CI 0.32, 1.68; P=0.446). Mean symptom scores in EORTC QLQ-C30 were significantly correlated with corresponding AE rates for fatigue (r=0.31), nausea/vomiting (r=0.50), pain (r=0.41), dyspnea (r=0.49), insomnia (r=0.35), constipation (r=0.30), and diarrhea (0.40; P≤0.03 for all comparisons). The most common treatment-related AEs (all grade incidence ≥25%) were alopecia (88.5%), fatigue (69.2%), peripheral neuropathy (69.2%), neutropenia (59.6%), nausea (46.2%), diarrhea (32.7%), anemia (25%), constipation (25%), and decreased appetite (25%).

Table. Qol EORTC QLQ-C30 Scores: Change from Baseline to Cycle 6 (n=44)Functional orCategory, n (%)Symptom ScaleImprovedStableWorsenedGHS/Qol13 (29.5)23 (52.3)8 (18.2)Physical10 (22.7)26 (59.1)8 (18.2)Role13 (29.5)20 (45.5)11 (25.0)Emotional17 (38.6)18 (40.9)9 (20.5)Cognitive6 (13.6)18 (40.9020 (45.5)Social12 (27.3)18 (40.9)14 (31.8)Fatigue14 (31.8)8 (18.2)22 (50.0)Nausea/vomiting9 (20.5)24 (54.5)11 (25.0)Pain21 (47.7)14 (31.8)9 (20.5)Dyspnea12 (27.3)19 (43.2)13 (29.5)

Conclusions: Given the improvements in pain and in arm and breast symptoms, long median time to deterioration in functioning/symptom scales in this analysis, and the tumor response rates and safety profile in the primary analysis, combination eribulin/TRAS may be an acceptable treatment option for locally recurrent or HER2+ MBC and merits further study in larger clinical trials.

Citation Format: Lee Schwartzberg, Sharon Wilks, Shannon Puhalla, Joyce O'Shaughnessy, Erhan Berrak, James Song, David Cox, Linda Vahdat. Quality of life results from a phase 2, multicenter, single-arm study of eribulin mesylate plus trastuzumab as first-line therapy for locally recurrent or metastatic HER2+ breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-17-03.

Ion thermal decoupling and species separation in shock-driven implosions

Anomalous reduction of the fusion yields by 50% and anomalous scaling of the burn-averaged ion temperatures with the ion-species fraction has been observed for the first time in D^{3}He-filled shock-driven inertial confinement fusion implosions. Two ion kinetic mechanisms are used to explain the anomalous observations: thermal decoupling of the D and ^{3}He populations and diffusive species separation. The observed insensitivity of ion temperature to a varying deuterium fraction is shown to be a signature of ion thermal decoupling in shock-heated plasmas. The burn-averaged deuterium fraction calculated from the experimental data demonstrates a reduction in the average core deuterium density, as predicted by simulations that use a diffusion model. Accounting for each of these effects in simulations reproduces the observed yield trends.

Clinical effects of prior trastuzumab on combination eribulin mesylate plus trastuzumab as first-line treatment for HER2+ locally recurrent or metastatic breast cancer (MBC): Results from a phase 2, single-arm, multicenter study

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Background: Eribulin mesylate, a novel nontaxane microtubule dynamics inhibitor in the halichondrin class of antineoplastic drugs, is indicated for women with MBC who previously received ≥ 2 chemotherapy regimens in the metastatic setting. Primary data from a phase 2 trial on first-line combination eribulin + trastuzumab (TRAS) in HER2+ patients (pts) showed a 71% objective response rate (ORR) and tolerability consistent with the known profile of these agents. Here we present prespecified endpoint data for this study by prior TRAS use. Methods: Pts with HER2+ MBC who had not received prior chemotherapy for MBC received eribulin mesylate 1.4 mg/m2 IV on days 1 and 8 of each 21-day cycle and initial TRAS (8 mg/kg IV/day 1), followed by 6 mg/kg/day 1 of each subsequent cycle. Response, progression-free survival (PFS), and tolerability were assessed in patients who had and had not received prior TRAS treatment. Results: The 52 pts (median age, 59.5 years) received combination eribulin + TRAS, for a median treatment duration of ~30 weeks; 40% (n=21) were previously treated with TRAS in the neo-adjuvant/adjuvant setting. There was median of 23 months since completion of adjuvant treatment prior to retreatment with eribulin + TRAS for first-line MBC.Efficacy, assessed by ORR, clinical benefit rate (CBR), PFS, and duration of response (DOR), was largely consistent in pts who received prior TRAS relative to pts who had not received prior TRAS (see table). Overall, grade (G) 3-5 adverse events (AEs), treatment-related AEs (TRAEs), and discontinuations (d/c) were similar between groups (Table). Conclusions: In this phase 2 single-arm trial in pts with HER2+ MBC, eribulin + TRAS demonstrated activity and was well tolerated as first-line treatment, irrespective of prior (neo) adjuvant TRAS treatment. Clinical trial information: NCT01269346. [Table: see text]

Clinical effects of prior anthracycline or taxane use on eribulin as first-line treatment for HER+/- locally recurrent or metastatic breast cancer (BC): Results from 2 phase 2, multicenter, single-arm studies

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Background: Eribulin mesylate, a nontaxane microtubule dynamics inhibitor, has demonstrated an overall survival benefit relative to other commonly used agents in patients (pts) with at least 2 prior MBC cytotoxic therapies. Primary data presented from 2 phase 2 trials, Study 206 (eribulin in HER2- BC pts) and Study 208 (combination eribulin + trastuzumab [TRAS] in HER2+ BC pts), showed clinical activity and acceptable tolerability profiles as first-line cytotoxic therapy (tx). Here we present prespecified efficacy data for both trials based on prior anthracycline (A) and taxane (T) use. Methods: In both studies, pts received eribulin mesylate 1.4 mg/m2 IV on days 1 and 8 of each 21-day cycle. Pts in Study 208 (HER2+) also received initial TRAS (8 mg/kg IV/Day 1), followed by 6 mg/kg/day 1 of each subsequent cycle. Objective response rate (ORR), progression-free survival (PFS), and tolerability were assessed. Results: In Study 206 (N=56), 48% and 46% received prior A and T, and in Study 208 (N=52), 21% and 44% received prior A and T, respectively. ORR, the primary endpoint, was similar in pts, regardless of prior A or T, except in pts w/o prior T in Study 208 whose ORR trended higher (table). Clinical benefit rate (CBR), PFS, and duration of response (DOR) were either similar or trended higher in pts w/o prior A or T. PFS was higher in HER2+ BC patients receiving eribulin + TRAS who had not received prior A or T compared with those who had. Grade (G) 3-5 adverse event rates were similar or lower in pts who had not received prior A or T. Conclusions: As first-line therapy, eribulin in HER2- BC pts and eribulin + TRAS in HER2+ BC pts were effective and well tolerated, regardless of prior A or T tx. However, in HER2+ BC pts receiving eribulin + TRAS, the lack of prior A or T tx may be a lead to longer median PFS. Clinical trial information: NCT01268150/NCT01269346. [Table: see text]