Development of tandem antigen capture ELISAs measuring QSOX1 isoforms in plasma and serum

QSOX1 is a sulfhydryl oxidase that has been identified as a potential biomarker in multiple cancer types as well as acute decompensated heart failure. Three anti-QSOX1 monoclonal antibodies (mAbs) were generated: 2F1, 3A10, and 56-3. MAbs 2F1 and 3A10 were generated against the short isoform of recombinant QSOX1 (rQSOX1-S), and mAb 56-3 was generated against a peptide (NEQEQPLGQWHLS) from the long isoform of QSOX1 (QSOX1-L). Using these mAbs, tandem antigen capture ELISAs were developed to quantify both short and long isoforms of QSOX1 (Total QSOX1 ELISA) and QSOX1-L (QSOX1-L ELISA) in serum and plasma samples. The Total QSOX1 ELISA pairs mAbs 2F1 and 3A10 and has a limit of detection of 109.5 pM, while the QSOX1-L ELISA pairs mAbs 2F1 and 56-3 and has a limit of detection of 10 pM. The levels of total QSOX1 and QSOX1-L were measured in a cohort of paired sera and plasma from 61 donors ≥40 years old and 15 donors <40 years old. No difference in QSOX1 levels was detected between QSOX1-L and QSOX1-S in serum, but the mean concentration of QSOX1-L was found to be 3.21 nM in serum and 5.63 nM in plasma (**p = 0.006). Our tandem ELISAs demonstrate the wide range of concentrations of QSOX1-L and QSOX1-S among individual serum and plasma samples. Since the epitope of mAb 2F1 was mapped to the first CxxC motif at residues C70 and C73 and mAb 56-3 was generated against NEQEQPLGQWHLS in QSOX1-L, our findings support previous research which suggested that QSOX1-L is secreted from cells despite a putative transmembrane domain. The ELISAs reported here may be a useful tool for investigating QSOX1 isoforms as potential biomarkers in cancer and/or heart failure.

P321 Development of a breath-based diagnostic for valley fever, an endemic fungal pneumonia

 

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Objectives

Valley fever (coccidioidomycosis) is an endemic pneumonia of the North and South American deserts, and is responsible for up to 30% of community-acquired pneumonia in endemic and highly populated areas of the US desert southwest. The causative agents of Valley fever are the dimorphic fungi Coccidioides immitis and C. posadasii, which grow as mycelia in the environment and spherules within the lungs of vulnerable hosts. The current diagnostics for Valley fever are severely lacking due to poor sensitivity and invasiveness, contributing to a 23-day median time-to-diagnosis. There is a critical need for novel diagnostics for detecting and identifying Valley fever lung infections. Our long-term goal is to develop a breath-based diagnostic for coccidioidomycosis lung infections. Our current objective is to identify and validate volatile biomarkers of C. immitis and C. posadasii infections via metabolomics analyses of in vitro cultures, mouse model lung infections, and lung specimens from humans with Valley fever. Thus far we have characterized the volatile organic compounds (VOCs) produced by C. immitis and C. posadasii in vitro and evaluated the relationship of the volatile metabolomes to lifecycle, and we have investigated the VOC profiles of bronchoalveolar lavage fluid (BALF) samples from mouse model lung infections of Valley fever.

Methods

For in vitro analyses, six strains each of C. immitis and C. posadasii were cultured in triplicate to induce mycelial or spherule formation. For mouse model infections, female C57BL/6 mice were infected by intranasal inoculation with C. immitis RS (n = 6), C. posadasii Silveira (n = 6), or vehicle control (n = 4), and BALF fluid was collected 10 days post-infection. The in vitro spent media and BALF sample VOCs were analyzed by headspace solid-phase microextraction and comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (SPME-GC × GC-TOFMS). The BALF samples were analyzed for cytokines using a mouse magnetic 26-Plex ProcartaPlexTM panel and the mouse spleen and brain were quantified for fungal dissemination. Data analysis: Hierarchical clustering analysis (HCA), principal component analysis (PCA), and Kendall correlation were performed on volatile and cytokine data.

Results

We detected a total of 353 VOCs that were at least two-fold more abundant in Coccidioides cultures versus medium controls and found the volatile metabolome of Coccidioides is more dependent on lifecycle (mycelia vs. spherule) than species (Fig. 1). The BALF samples indicate that lung infection VOCs are correlated to cytokine production (Fig. 2) and classify mice based on their individual level of infection. We did not observe any separation between the C. immitis and C. posadasii infected mice by their BALF VOCs via PCA; however, separation of these classes was observed by PCA of the cytokines.

Conclusions

Our pilot data indicate that Coccidioides spp. and the host produce volatile metabolites that may yield biomarkers for a Valley fever breath test. We have collected BALF and sputum from human patients with community-acquired pneumonia, and the next steps will be to determine which Valley fever biomarkers can differentiate between bacterial and fungal etiologies of disease.

Intranasal Immunization with a Vaccinia Virus Vaccine Vector Expressing Pre-Fusion Stabilized SARS-CoV-2 Spike Fully Protected Mice against Lethal Challenge with the Heavily Mutated Mouse-Adapted SARS2-N501YMA30 Strain of SARS-CoV-2

The Omicron SARS-CoV-2 variant has been designated as a variant of concern because its spike protein is heavily mutated. In particular, the Omicron spike is mutated at five positions (K417, N440, E484, Q493, and N501) that have been associated with escape from neutralizing antibodies induced by either infection with or immunization against the early Washington strain of SARS-CoV-2. The mouse-adapted strain of SARS-CoV-2, SARS2-N501Y_MA30, contains a spike that is also heavily mutated, with mutations at four of the five positions in the Omicron spike associated with neutralizing antibody escape (K417, E484, Q493, and N501). In this manuscript, we show that intranasal immunization with a pre-fusion stabilized Washington strain spike, expressed from a highly attenuated, replication-competent vaccinia virus construct, NYVAC-KC, fully protected mice against symptoms and death from SARS2-N501Y_MA30. Similarly, immunization by scarification on the skin fully protected against death, but not from mild disease. This data demonstrates that the Washington strain spike, when expressed from a highly attenuated, replication-competent poxvirus—administered without parenteral injection—can fully protect against the heavily mutated mouse-adapted SARS2-N501Y_MA30.

Intranasal immunization with a vaccinia virus vaccine vector expressing pre-fusion stabilized SARS-CoV-2 spike fully protected mice against lethal challenge with the heavily mutated mouse-adapted SARS2-N501Y MA30 strain of SARS-CoV-2

The Omicron SARS-CoV-2 variant has been designated a variant of concern because its spike protein is heavily mutated. In particular, Omicron spike is mutated at 5 positions (K417, N440, E484, Q493 and N501) that have been associated with escape from neutralizing antibodies induced by either infection with or immunization against the early Washington strain of SARS-CoV-2. The mouse-adapted strain of SARS-CoV-2, SARS2-N501Y _MA30 , contains a spike that is also heavily mutated, with mutations at 4 of the 5 positions in Omicron spike associated with neutralizing antibody escape (K417, E484, Q493 and N501). In this manuscript we show that intranasal immunization with a pre-fusion stabilized Washington strain spike, expressed from a highly attenuated, replication-competent vaccinia virus construct, NYVAC-KC, fully protected mice against disease and death from SARS2-N501Y _MA30 . Similarly, immunization by scarification on the skin fully protected against death, but not from mild disease. This data demonstrates that Washington strain spike, when expressed from a highly attenuated, replication-competent poxvirus, administered without parenteral injection can fully protect against the heavily mutated mouse-adapted SARS2-N501Y _MA30 .

Intranasal immunization with a vaccinia virus vaccine vector expressing pre-fusion stabilized SARS-CoV-2 spike fully protected mice against lethal challenge with the heavily mutated mouse-adapted SARS2-N501Y MA30 strain of SARS-CoV-2

The Omicron SARS-CoV-2 variant has been designated a variant of concern because its spike protein is heavily mutated. In particular, Omicron spike is mutated at 5 positions (K417, N440, E484, Q493 and N501) that have been associated with escape from neutralizing antibodies induced by either infection with or immunization against the early Washington strain of SARS-CoV-2. The mouse-adapted strain of SARS-CoV-2, SARS2-N501Y MA30 , contains a spike that is also heavily mutated, with mutations at 4 of the 5 positions in Omicron spike associated with neutralizing antibody escape (K417, E484, Q493 and N501). In this manuscript we show that intranasal immunization with a pre-fusion stabilized Washington strain spike, expressed from a highly attenuated, replication-competent vaccinia virus construct, NYVAC-KC, fully protected mice against disease and death from SARS2-N501Y MA30 . Similarly, immunization by scarification on the skin fully protected against death, but not from mild disease. This data demonstrates that Washington strain spike, when expressed from a highly attenuated, replication-competent poxvirus, administered without parenteral injection can fully protect against the heavily mutated mouse-adapted SARS2-N501Y MA30 .

303. Physiological Changes Due to Bloodstream Infection in Intensive Care Unit Patients Differ According to Transplant Status

Background

Transplant recipients are at increased risk of bloodstream infection (BSI), which often leads to critical illness. Due to immunosuppression, BSI in these patients may manifest with different pathophysiology compared to non-transplant recipients. We aimed to identify different trends in the pathophysiology of critically ill patients with BSI based on transplant status.

Methods

We reviewed data from patients admitted to the medical and surgical/trauma intensive care units (ICUs) at the University of Virginia Medical Center from 2011 to 2015. We included both solid organ and hematopoietic stem cell transplant recipients. We performed univariate logistic regression modeling to evaluate trends in different physiological features in both transplant and non-transplant recipients in the 96 hours surrounding a positive blood culture. We then performed multivariate logistic regression modeling to identify features independently associated with a positive blood culture in the next 24 hours in transplant recipients.

Results

We analyzed 9,954 ICU patient-admissions (including 505 transplant recipients), with a total of 144 patient-years of physiological data, 1.3 million hourly measurements, and 15,577 blood culture instances. Of the 1,068 blood culture instances in transplant recipients, 125 (12%) were positive, compared to 1,051 of 14,509 (7%) blood culture instances in non-transplant recipients. Critically ill transplant recipients with BSI had greater abnormalities in vital signs, oxygen requirement, markers of organ damage, APACHE score, and Charlson Comorbidity Index (CCI) compared to non-transplant recipients (Figure 1). Trends in many of these features also differed based on transplant status. The multivariable logistic regression model of BSI in transplant recipients included, in decreasing strength of association: total bilirubin, systolic blood pressure, fraction of inspired oxygen, number of intravenous lines, and CCI. This model had an AUC of 0.75.

Figure 1. Trends in pathophysiological abnormalities in 9,954 critically ill patients with BSI based on transplant status, 2011–2015. Each graph demonstrates the average value of the physiological variable over time relative to the acquisition of a positive blood culture. Blue curves depict trends in transplant recipients, while red curves depict trends in non-transplant recipients. We assessed 108 physiological features and show the 24 features with the greatest change around the time of blood culture.

Conclusion

Critically ill transplant recipients have a higher prevalence of BSI and different pathophysiological manifestations of BSI compared to non-transplant recipients. This may have implications regarding early detection and treatment of BSI in these patients.

Disclosures

Randall Moorman, MD, Advanced Medical Predictive Devices, Diagnostics, and Displays (Board Member, Shareholder)

The Brightest Rainbow Follows the Darkest Storm

A parent’s perspective on pulmonary vein stenosis through the experience of two children with the disease.

Retrospective clinical evaluation of 4 lateral flow assays for the detection of SARS-CoV-2 IgG

In a Clinical Laboratory Improvement Amendments laboratory setting, we evaluated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG detection with 4 lateral flow immunoassays [LFIAs; 2 iterations from BTNX Inc. (n = 457) and 1 each from ACON Laboratories (n = 200) and SD BIOSENSOR (n = 155)]. In a cohort of primarily hospitalized, reverse-transcription polymerase chain reaction-confirmed coronavirus disease 2019 cases, sensitivity at ≥14 days from symptom onset was: BTNX kit 1, 95%; BTNX kit 2, 91%; ACON, 95%; and SD, 92%. All assays showed good concordance with the Abbott SARS-CoV-2 IgG assay at ≥14 days from symptom onset: BTNX kit 1, 99%; BTNX kit 2, 94%; ACON, 99%; and SD, 100%. Specificity, measured using specimens collected prior to SARS-CoV-2 circulation in the United States and "cross-reactivity challenge" specimens, was 98% for BTNX kit 1 and ACON and 100% for BTNX kit 2 and SD. These results suggest that LFIAs may provide adequate results for rapid detection of SARS-CoV-2.

Pre-Vent: the prematurity-related ventilatory control study

BACKGROUND

The increasing incidence of bronchopulmonary dysplasia in premature babies may be due in part to immature ventilatory control, contributing to hypoxemia. The latter responds to ventilation and/or oxygen therapy, treatments associated with adverse sequelae. This is an overview of the Prematurity-Related Ventilatory Control Study which aims to analyze the under-utilized cardiorespiratory continuous waveform monitoring data to delineate mechanisms of immature ventilatory control in preterm infants and identify predictive markers.

METHODS

Continuous ECG, heart rate, respiratory, and oxygen saturation data will be collected throughout the NICU stay in 500 infants < 29 wks gestation across 5 centers. Mild permissive hypercapnia, and hyperoxia and/or hypoxia assessments will be conducted in a subcohort of infants along with inpatient questionnaires, urine, serum, and DNA samples.

RESULTS

Primary outcomes will be respiratory status at 40 wks and quantitative measures of immature breathing plotted on a standard curve for infants matched at 36-37 wks. Physiologic and/or biologic determinants will be collected to enhance the predictive model linking ventilatory control to outcomes.

CONCLUSIONS

By incorporating bedside monitoring variables along with biomarkers that predict respiratory outcomes we aim to elucidate individualized cardiopulmonary phenotypes and mechanisms of ventilatory control contributing to adverse respiratory outcomes in premature infants.

Abstract P6-18-30: Phase Ib/II study of capecitabine 7/7 schedule with neratinib in patients with HER2-positive metastatic breast cancer (MBC)

Background: Neratinib (N) is a potent irreversible inhibitor of HER1, HER2, and HER4 and has been shown to have antitumor activity in patients (pts) with human epidermal growth factor receptor 2 (HER2) - positive breast cancer. A previous study of combination of neratinib with capecitabine (X) was associated with &gt; G 3 diarrhea in &gt; 20% of patients. Currently, the NALA study is evaluating this combination of N with X at standard schedule against control. X at 7 day on and 7 day off schedule (7/7) has been shown to be well-tolerated with less ≥G3 toxicities. We are conducting a phase Ib/II study of N with X (7/7) in pts with pretreated HER2+ MBC (NCT03377387). Methods: Eligible pts had HER2+ MBC, normal left ventricular ejection fraction (LVEF ≥ 50%); pts can have any and up to 4 prior chemotherapy-based treatments in phase Ib and II portions, respectively. Primary endpoints are to define maximum tolerated dose and efficacy in phase I and phase II portions, respectively. Secondary endpoints include safety and tolerability; exploratory endpoint is to quantify cell-free DNA to correlate with response for phase II portion. There were 4 cohorts for phase Ib with dose level 1 with starting dose of X at 1500 mg BID at 7/7 schedule with N at 240 mg daily. Results: As of July 1, 2018 8 pts have been enrolled in 2 cohorts. The median age is 63y (range: 57-79), and median ECOG is 0 (range: 0-1). 4 patients were treated at dose level 1 and 2 of 4 patients experienced dose-limiting toxicity with G3 diarrhea during cycle 1. Other significant toxicities included G3 hand foot syndrome (n=1), G3 fatigue (n=1) and G3 nausea (n=1). Three pts have now been treated at dose level -1 (X at 1000 mg twice daily 7/7 and N at 240 mg daily) and no ≥ G3 toxicities has been noted. Once MTD is reached, the phase II portion will occur to assess the efficacy and to further establish the safety and tolerability of capecitabine and neratinib at the MTD. Conclusions: The phase Ib/II study combining neratinib and capecitabine 7/7 is ongoing and updated result will be presented.

Citation Format: Wang R, Singh J, Sterlin V, Goldstein M, Lake D, Wong S, Baselga J, Norton L, Dang C. Phase Ib/II study of capecitabine 7/7 schedule with neratinib in patients with HER2-positive metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-30.

Abstract P4-21-34: Phase II study of gemcitabine, trastuzumab, and pertuzumab for HER2-Positive metastatic breast cancer after prior pertuzumab-based therapy

Background: The combination of taxanes with trastuzumab (H) and pertuzumab (P) for first line treatment of HER2-positive metastatic breast cancer (MBC) is associated with improved progression-free survival (PFS) and overall survival (OS). Treatment per physician's choice with anti-HER2 therapy after second line therapy is associated with a median PFS of 3 months. While continued use of H in therapeutic combinations after progression on H-based therapy is common, the efficacy of continuing HP-based treatment after progression on P-based therapy is unknown.

Methods: This is a single arm phase II trial of gemcitabine (G) with HP. Eligible patients had HER2-positive (IHC 3+ or FISH ≥ 2.0) MBC with prior HP-based treatment and ≤ 3 prior chemotherapies. Patients received G (1200 mg/m2) on days 1 and 8 of a q 3 week (w) cycle, and H (8 mg/kg load → 6 mg/kg) and P (840 mg load → 420 mg) q3w. The primary endpoint is PFS at 3 months. Secondary endpoints include OS, safety and tolerability. An exploratory endpoint is to compare PFS by RECIST criteria versus 18-F FDG-PET response criteria. Using a Simon optimal 2-stage design, 21 patients were enrolled in stage 1. The successful 3-month PFS rate for stage 1 was set at 57% to allow accrual to stage 2 for a total of 45 patients. The study therapy will be considered successful if at least 27/45 (60%) patients are progression free at 3 months.

Results: As of June 9, 2016, 28 patients are enrolled; 21 are evaluable at 3 months and 7 have not had 3-month evaluation. At 3 months, 16/21 (76%) are progression free; 5 patients have progressed. The 3 month-PFS results for evaluable patients will be updated. There are no cardiac or febrile neutropenic events to date. Initially, 5 of 22 (23%) patients required G dose reduction (4 due to grade 3 neutropenia and 1 due to grade 3 vomiting) and the study was amended to lower initial G dose to 1000 mg/m2.

Conclusions: The preliminary 3 month-PFS is 76% (95% CI 55% to 89%) in evaluable patients, and updated data will be presented. These findings suggest clinical benefit when P is continued beyond progression.

Citation Format: Iyengar NM, Smyth L, Lake D, Gucalp A, Singh JC, Traina TA, DeFusco P, Dickler MN, Fornier MN, Goldfarb S, Jhaveri K, Modi S, Troso-Sandoval T, Argolo D, Jack K, Ulaner G, Jochelson M, Baselga J, Norton L, Hudis CA, Dang CT. Phase II study of gemcitabine, trastuzumab, and pertuzumab for HER2-Positive metastatic breast cancer after prior pertuzumab-based therapy [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 P4-21-34.

Corneal collagen crosslinking for keratoconus or corneal ectasia without epithelial debridement

PURPOSE

Corneal collagen crosslinking (CXL) is a relatively new technique to reduce the progression of keratoconus. The technique can be performed with or without complete debridement of the corneal epithelium. We describe a novel intermediate technique involving mechanical disruption of the epithelium, and evaluate its safety and efficacy.

METHODS

The case notes of 128 eyes with progressive keratoconus or iatrogenic corneal ectasia who had undergone CXL using the epithelial disruption technique were retrospectively reviewed. Thin corneas were treated with hypotonic riboflavin. All others were treated with an isotonic solution. Note was made of preoperative and postoperative parameters, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, endothelial cell count, and corneal tomography. Occurrence of procedure-related complications was recorded. Statistical analyses were performed using the paired sample t-test and Wilcoxon signed-rank test, with a level of P<0.05 being accepted as statistically significant.

RESULTS

At 12 months, 41.8% of patients treated with isotonic riboflavin had improved UCVA and 29.7% had improved BSCVA. Only 13.4% lost lines of UCVA and 14.9% lost BSCVA. Of the patients treated with hypotonic riboflavin, at 12 months, 75% demonstrated stability of BSCVA and 25% had stable Kmax. In addition, 25% showed improved visual acuity at 12 months, and 58.3% showed regression of their Kmax. Our rate of short-term complications was comparable to studies using complete epithelial removal.

CONCLUSIONS

CXL with epithelial disruption is a safe and effective treatment for keratoconus or iatrogenic corneal ectasia, and may be better tolerated by patients than the epithelium-off technique.

Endoscopic ultrasonography-guided portal injection chemotherapy for hepatic metastases

INTRODUCTION

We hypothesized that endoscopic ultrasonography-guided portal injection chemotherapy (EPIC) using irinotecan-loaded microbeads may achieve increased intrahepatic concentrations, while decreasing systemic exposure. This may achieve enhanced efficacy for the treatment of diffuse liver metastases, while decreasing systemic toxicities.

MATERIALS AND METHODS

In eight anesthetized 35 kg pigs, EPIC was performed transgastrically using the linear-array echoendoscope and a 22 g fine-needle aspiration. In four animals, irinotecan (100 mg) loaded onto 75-150 micron liquid chromatography (LC) beads was injected. In four animals, saline was injected into the portal vein and unloaded irinotecan (100 mg) was injected into the jugular vein. Plasma (every 15 min), and at 1 h bone marrow, liver and skeletal muscle samples were obtained. Irinotecan and SN-38 (active metabolite) concentrations were assayed by LC/mass spectrometry.

RESULTS

The procedure was performed safely in all eight animals. Compared with systemic administration, EPIC resulted in almost twice the hepatic concentration of irinotecan (6242 vs. 3692 ng/g) and half the systemic concentrations in plasma (1092 vs. 2762 ng/mL), bone marrow (815 vs. 1703 ng/mL) and skeletal muscle (521 vs. 1058 ng/g). SN-38 levels were lower with EPIC (liver: 166 vs. 681 ng/g; plasma: 1.8 vs. 2.4 ng/mL; bone marrow: 0.9 vs. 1.4 ng/mL; muscle 4.6 vs. 9.2 ng/g). Liver histology showed the beads within small portal venules.

CONCLUSIONS

EPIC using irinotecan-loaded microbeads can enhance hepatic exposure to irinotecan, while decreasing systemic concentrations. SN-38 levels were lower with EPIC indicating that a substantial portion of the irinotecan was still loaded onto beads. The microbeads may act as a reservoir resulting in prolonged hepatic drug exposure.

Abstract P5-20-07: Phase II Trial of Dasatinib in Combination With Weekly Paclitaxel for Patients with Metastatic Breast Carcinoma

Background: Src kinase plays an important role in proliferation, survival, angiogenesis and metastasis in several malignancies including breast cancer. Therefore, inhibition of Src and other tyrosine kinases (TKs) represents a novel therapeutic approach. Dasatinib is a potent inhibitor of 5 oncogenic TKs, inhibits VEGF-stimulated proliferation, has potent bone anti-resorptive activity and selectively inhibits basal-type breast cancer growth. Preclinically, the combination of dasatinib and paclitaxel had superior antitumor activity to either agent alone. In a previous phase I study, we determined that, in combination with weekly paclitaxel, the optimum dose of dasatinib was 120mg. Of note, 4/9 (44%) patients treated at or above this dasatinib dose level had objective tumor response. We now present results from the phase II trial of this combination.

Methods: Patients with MBC, ECOG PS 0–1, normal hepatic, renal, marrow function were eligible. Patients had measurable, HER2-negative metastatic breast cancer (MBC), ≤2 prior therapies for MBC. Treatment consisted of weekly paclitaxel 80 mg/m2 IV 3/4 weeks + Dasatinib 120mg orally daily. Response was assessed by RECIST after every 8 weeks of therapy. Simon's two-stage optimal design was used to test the null hypothesis of a 15% response rate (RR) against the alternative of a 30% RR. In stage I, planned enrollment was 23 patients based on Type I and Type II errors of 10%. If 4 or more responses are observed, enrollment will be extended to 55 patients. Exploratory correlative biomarkers of clinical benefit include Src phosphorylation (p-Src) in peripheral blood mononuclear cells, plasma levels of VEGFR2 and collagen Type IV, circulating tumor cells (CTCs) and tumor gene expression profiling.

Results: 21 patients (19 females, 2 male) have enrolled; median age 48 (range 30–79). Patients received a median of 1 prior therapy for MBC (range 0–2). 6 patients are not assessable for response: 1 has received &lt;8 weeks treatment, 5 came off study for toxicity (2 hypersensitivity reaction to paclitaxel, 1 infection, 1 diarrhea/nausea, 1 bleeding likely related to anticoagulation). Among the 15 patients assessable for response, best response to date is as follows: 2 (13%) patients partial response, 11 (73%) patients stable disease (SD) and 2 (13%) patients progression of disease. Of patients with SD, 6/11 (55%) continue on treatment after median of 2 months (range 2–10) and 5/11 (45%) patients have come off study after median of 10 months (range 3–21). Most toxicities have been hematological and low grade. Diarrhea and neuropathy have generally been low grade and no new toxicities related to the combination have occurred since expansion into the phase II. Potential biomarkers of clinical benefit including, p-Src, VEGFR2, collagen Type IV, and CTCs will be presented.

Conclusion: Data from this phase II has demonstrated preliminary evidence of activity for weekly paclitaxel and dasatinib 120mg in patients with MBC. These findings are consistent with data from this dose level in the earlier phase I study. Predictive biomarkers of clinical benefit are under investigation.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-20-07.

Abstract P1-13-11: Adjuvant treatment of early-stage breast cancer with eribulin mesylate following dose-dense doxorubicin and cyclophosphamide: preliminary results from a phase 2, single-arm feasibility study

Background: Despite recent improvements in breast cancer outcomes, patients (pts) with high-risk, early-stage breast cancer continue to experience recurrences and death due to disease. Chemotherapy regimens with the ability to extend survival remain an important drug development goal. Eribulin mesylate has demonstrated antitumor activity and improved overall survival (OS) in pts with heavily pretreated, locally recurrent or metastatic breast cancer when compared to treatment of physician's choice. This study examines the feasibility of eribulin as adjuvant therapy following dose-dense (dd) doxorubicin (A) and cyclophosphamide (C) in patients with early-stage breast cancer.

Methods: Eligible pts have histologically confirmed, HER2-normal, stage I-III invasive breast cancer and adequate bone marrow, liver, and renal function. Treatment consists of dd AC (A 60mg/m2 IV; C 600mg/m2 IV) on Day 1 of each 14-day cycle x4 cycles, followed by eribulin mesylate 1.4mg/m2 IV over 2–5min on Days 1 and 8 every 21 days x4 cycles. Radiation/hormonal therapy were allowed per standard of care. The primary objective of feasibility is defined as the ability to complete 4 cycles of eribulin without a treatment-related dose delay (defined as &gt;2 days) or reduction. Feasibility rates will be reported for pts with and without growth factor use. Secondary/exploratory endpoints include evaluation of the safety via NCI-CTCAEv4 of 4 cycles of AC followed by 4 cycles of eribulin, and 3-year disease-free survival and OS.

Results: As of 5/22/12, 46 of 80 planned pts have been treated; 38 pts have had ≥1 dose of eribulin and are evaluable for eribulin-related toxicity. Pt characteristics are as follows: median age 50 yrs (27–65 yrs); 100% female; ECOG of 0=81.6%; breast cancer stage at study entry: stg 1: 7.5%; stg 2: 72.5%, stg 3: 20%. Select treatment-related AEs are reported as total (all cycles) and eribulin-related events; many AEs overlapped during treatment (Table).

Genome-wide characterization of pancreatic adenocarcinoma patients using next generation sequencing

Pancreatic adenocarcinoma (PAC) is among the most lethal malignancies. While research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult and the majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to genomically characterize individual PAC patients to understand the range of aberrations that are occurring in each tumor. Because our understanding of PAC tumorigenesis is limited, evaluation of separate cases may reveal aberrations, that are less common but may provide relevant information on the disease, or that may represent viable therapeutic targets for the patient. We used next generation sequencing to assess global somatic events across 3 PAC patients to characterize each patient and to identify potential targets. This study is the first to report whole genome sequencing (WGS) findings in paired tumor/normal samples collected from 3 separate PAC patients. We generated on average 132 billion mappable bases across all patients using WGS, and identified 142 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. We did not identify any significant somatic translocation events. We also performed RNA sequencing on 2 of these patients' tumors for which tumor RNA was available to evaluate expression changes that may be associated with somatic events, and generated over 100 million mapped reads for each patient. We further performed pathway analysis of all sequencing data to identify processes that may be the most heavily impacted from somatic and expression alterations. As expected, the KRAS signaling pathway was the most heavily impacted pathway (P<0.05), along with tumor-stroma interactions and tumor suppressive pathways. While sequencing of more patients is needed, the high resolution genomic and transcriptomic information we have acquired here provides valuable information on the molecular composition of PAC and helps to establish a foundation for improved therapeutic selection.

Genome-wide characterization of pancreatic adenocarcinoma patients using next generation sequencing

Pancreatic adenocarcinoma (PAC) is among the most lethal malignancies. While research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult and the majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to genomically characterize individual PAC patients to understand the range of aberrations that are occurring in each tumor. Because our understanding of PAC tumorigenesis is limited, evaluation of separate cases may reveal aberrations, that are less common but may provide relevant information on the disease, or that may represent viable therapeutic targets for the patient. We used next generation sequencing to assess global somatic events across 3 PAC patients to characterize each patient and to identify potential targets. This study is the first to report whole genome sequencing (WGS) findings in paired tumor/normal samples collected from 3 separate PAC patients. We generated on average 132 billion mappable bases across all patients using WGS, and identified 142 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. We did not identify any significant somatic translocation events. We also performed RNA sequencing on 2 of these patients' tumors for which tumor RNA was available to evaluate expression changes that may be associated with somatic events, and generated over 100 million mapped reads for each patient. We further performed pathway analysis of all sequencing data to identify processes that may be the most heavily impacted from somatic and expression alterations. As expected, the KRAS signaling pathway was the most heavily impacted pathway (P<0.05), along with tumor-stroma interactions and tumor suppressive pathways. While sequencing of more patients is needed, the high resolution genomic and transcriptomic information we have acquired here provides valuable information on the molecular composition of PAC and helps to establish a foundation for improved therapeutic selection.

Cancer of the ampulla of Vater: analysis of the whole genome sequence exposes a potential therapeutic vulnerability

Background

Recent advances in the treatment of cancer have focused on targeting genomic aberrations with selective therapeutic agents. In rare tumors, where large-scale clinical trials are daunting, this targeted genomic approach offers a new perspective and hope for improved treatments. Cancers of the ampulla of Vater are rare tumors that comprise only about 0.2% of gastrointestinal cancers. Consequently, they are often treated as either distal common bile duct or pancreatic cancers.

Methods

We analyzed DNA from a resected cancer of the ampulla of Vater and whole blood DNA from a 63 year-old man who underwent a pancreaticoduodenectomy by whole genome sequencing, achieving 37× and 40× coverage, respectively. We determined somatic mutations and structural alterations.

Results

We identified relevant aberrations, including deleterious mutations of KRAS and SMAD4 as well as a homozygous focal deletion of the PTEN tumor suppressor gene. These findings suggest that these tumors have a distinct oncogenesis from either common bile duct cancer or pancreatic cancer. Furthermore, this combination of genomic aberrations suggests a therapeutic context for dual mTOR/PI3K inhibition.

Conclusions

Whole genome sequencing can elucidate an oncogenic context and expose potential therapeutic vulnerabilities in rare cancers.

Abstract 5104: Identification of key tumorigenic pathways in pancreatic adenocarcinoma patients using massively parallel DNA and RNA sequencing

Purpose: Pancreatic adenocarcinoma is among the most lethal forms of all malignancies. While significant research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult. The majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to assess global somatic events across multiple pancreatic tumors by using next-generation sequencing technologies (NGS). Experimental Design: We performed whole genome sequencing (WGS) on paired tumor and normal samples from 3 pancreatic adenocarcinoma patients. Additionally, we performed whole transcriptome sequencing (WTS) on 2 of these patients’ tumors for which tumor RNA was available. Results: We generated on average 132 billion mappable bases across all patients using WGS, and identified 140 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. Data from WGS and WTS were integrated and analyzed to identify the most heavily affected pancreatic cancer pathways across all patients. The KRAS signaling pathway was identified as the most significant map. Unbiased global pathway analysis was also performed to identify processes that may be impacted. Consistent with the previous analysis, the most significant pathway from this analysis is also KRAS signaling. This integrated analysis specifically identifies heavily affected pathways in pancreatic cancer and pinpoints genes and processes that may be considered as targets for more effective therapies. Conclusions: While sequencing of additional patients is necessary to strengthen selection of key pathways, we demonstrate the utility of using NGS to understand the processes driving pancreatic adenocarcinoma so that standardized treatments for patients may be improved.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5104. doi:1538-7445.AM2012-5104

Calculation of shear stiffness in noise dominated magnetic resonance elastography data based on principal frequency estimation

Magnetic resonance elastography (MRE) is a non-invasive phase-contrast-based method for quantifying the shear stiffness of biological tissues. Synchronous application of a shear wave source and motion encoding gradient waveforms within the MRE pulse sequence enable visualization of the propagating shear wave throughout the medium under investigation. Encoded shear wave-induced displacements are then processed to calculate the local shear stiffness of each voxel. An important consideration in local shear stiffness estimates is that the algorithms employed typically calculate shear stiffness using relatively high signal-to-noise ratio (SNR) MRE images and have difficulties at an extremely low SNR. A new method of estimating shear stiffness based on the principal spatial frequency of the shear wave displacement map is presented. Finite element simulations were performed to assess the relative insensitivity of this approach to decreases in SNR. Additionally, ex vivo experiments were conducted on normal rat lungs to assess the robustness of this approach in low SNR biological tissue. Simulation and experimental results indicate that calculation of shear stiffness by the principal frequency method is less sensitive to extremely low SNR than previously reported MRE inversion methods but at the expense of loss of spatial information within the region of interest from which the principal frequency estimate is derived.

Efficacy of TRAIL treatment against HPV16 infected cervical cancer cells undergoing senescence following siRNA knockdown of E6/E7 genes

In this study we investigated E6 and E7 oncogenes from the Human Papilloma Virus as targets for siRNA knockdown in order to boost the efficacy of the anti-cancer drug 'tumor necrosis factor-related apoptosis inducing ligand' (TRAIL). SiHa cells were treated with TRAIL following transfection with E6/E7 siRNA and the expression of death receptors DR4 and DR5, cell viability, apoptosis, senescence and cell cycle analysis were undertaken using flow cytometry, MTT viability assay and cellular β-galactosidase activity assays. E6/E7 siRNA resulted in significant upregulation of death receptors DR4 and DR5 but did not result in an enhanced sensitivity to TRAIL. Our results indicate that E6/E7-siRNA induces senescence rather than apoptosis in SiHa cells. The occurrence of senescence in drug resistant cervical cancer cells such as the SiHa cell line by E6/E7 siRNA, among other factors, may prevent TRAIL induced activation of extrinsic and intrinsic pathways that lead to apoptotic cell death. Our findings are significant for combinatorial strategies for cancer therapy since the induction of senescence can preclude apoptosis rendering cells to be recalcitrant to TRAIL treatment.

Abstract P6-12-09: A Phase I-II Trial of Dasatinib (D) in Combination with Weekly (w) Paclitaxel (P) for Patients (Pts) with Metastatic Breast Carcinoma (MBC)

Background: Inhibition of SRC is a novel approach for MBC. D is an inhibitor of multiple tyrosine kinases, including the SRC family. Pre-clinical data show D inhibits multiple breast cancer cell lines, including those of “basal-like” subtype. In preclinical models D + P had superior antitumor activity to either agent alone. We designed this phase I-II study to translate this observation.

Methods: For phase I: pts with MBC, ECOG PS 0-1, normal hepatic, renal, marrow function were eligible. Pts with pleural/pericardial effusions were excluded. For phase II: pts had measurable, HER2-negative MBC, ≥2 prior rx for MBC. Prior taxanes, stable brain metastases and baseline neuropathy grade ≥1 were allowed. Cycle (C) consisted of wP 80 mg/m2 IV 3/4 weeks + D 70mg orally daily; escalating to 100 mg, 120 mg and 150 mg in cohorts of 3pts. Toxicity was assessed by CTCAE v3.0, response by RECIST.

Results: 17 pts enrolled (15 phase I; 2 phase II); median age 54 (range 35-74), median PS=1 (range 0-1). 12 (71%) pts rcvd prior adjuvant chemoRx. Pts rcvd a median of 3 prior rx for MBC (range 0-12). Pts rcvd median of 2 C of D + P (range 1-14). One DLT occurred at 150mg (G3 fatigue); this cohort was expanded with no further DLTs. However 3 pts on this dose level withdrew;1 pt delayed hypersensitivity rash (grade 1), 1 pt febrile neutropenia (grade 3), 1 pt paclitaxel pneumonitis (grade 3). Therefore the phase II dose is D 120mg. Overall the most common toxicities have been hematologic and low G (table). 13 pts are assessable for response; 4 patients (31%) had a PR, including 3 patients previously treated with taxanes. 5 pts (29%) had stable disease.

Toxicities &gt; Grade 1

Conclusion: Treatment with wP and D is feasible in pts with MBC. In the phase I study, 1 DLT occurred at D 150mg but due to cumulative toxicities the recommended dose for the ongoing phase II study is 120mg. Preliminary evidence of activity has been seen in taxane-pretreated pts at the phase II dose. Identification of biomarkers to select appropriate pts for this therapeutic approach is the subject of ongoing correlative studies.

Safety of a novel capecitabine dosing schedule when combined with lapatinib in patients with HER2-positive metastatic breast cancer refractory to trastuzumab

1131

Background: Capecitabine (C) is active in breast cancer and is usually dosed for 14 days (d) followed by a 7d rest (14 - 7). We described a mathematical method which predicts the optimal schedule for C to be 7d followed by a 7d rest (7 - 7) (Norton et al, Amer Assn Can Res. 2005). The MTD of C(7 - 7) is 2,000mg BID (Traina et al, J Clin Oncol. April 2008). Lapatinib (L) improves time to progression when added to C(14 - 7) in patients (pts) with HER-2-positive (+) metastatic breast cancer (MBC) that progressed after trastuzumab (T). To optimize this effective combination, we are testing C(7 - 7) + L in a phase II trial. Methods: Eligible pts have measurable, HER-2(+) MBC that has progressed after T. HER-2(+)=IHC 3+ or FISH>2. Pts have normal LVEF by MUGA, ECOG performance status (PS) <2 and normal organ function. <3 prior chemotherapy (CRx) regimens are permitted. Prior fluoropyrimidine is excluded. Therapy (tx) consists of C (2,000 mg BID, 7 - 7) and L (1,250 mg, daily). Cycle length = 4 wk. Pts are evaluated for toxicity q4 weeks (wk), for response q12wk; LVEF by MUGA q12wk. Primary endpoint: response rate (RR). Secondary endpoints: toxicity, stable disease >6 months, PFS. Using a Simon optimal 2-stage design, with alpha = 10%, power = 90% to discriminate between RR 10% and 25%, 21 pts will be accrued to the first stage. If >2 pts respond, 29 additional pts will be enrolled. If >7/ 40 pts respond, then C(7 - 7) + L will be considered worthy of further study. Results: As of January 5, 2008, 6 pts are enrolled and evaluable. Median (med) age 64 yrs (42–71), med ECOG PS 1 (0–1), ER/PR(+) 3, HER-2(+) 6, sites of MBC: bone (2), viscera (4), soft tissue (5). Med baseline LVEF 62% (51–68%). Prior tx: Adjuvant: CRx (5), hormone tx (3), T (3); MBC: CRx (2), hormone tx (1), T (3). After a med of 3 cycles (1–4), there were no grade 3, 4, or 5 events. Tx-related toxicity is: Gr 2 fatigue (1); Gr 1 AST (4), diarrhea (3), ALT (2), vomiting (1), hand-foot (1), fatigue (1). No withdrawls due to reduced LVEF. Two pts evaluable for response: PR = 1, SD<6 mo = 1. Conclusions: Capecitabine (7 - 7) + lapatinib appears well tolerated compared to C(14 - 7)+L (Geyer et al). Additional safety and efficacy data is anticipated prior to this meeting.

[Table: see text]

Randomized phase II trial of nanoparticle albumin-bound paclitaxel in three dosing schedules with bevacizumab as first-line therapy for HER2-negative metastatic breast cancer (MBC)

1006

Background: Nanoparticle albumin-bound paclitaxel (nab-P) 260 mg/m2 is superior to paclitaxel 175 mg/m2 (P) every 3 weeks (Gradishar et al., J Clin Oncol. 2005). Weekly uninterrupted P is more effective than q3wk P in MBC (Seidman et al., J Clin Oncol. 2008). Bevacizumab (bev) nearly doubles response rate and time to progression (TTP) when added to P as 1st line therapy for MBC (Miller et al., N Engl J Med. 2007). Methods: This open-label, phase II study randomized patients (pts) to nab-P at 260 mg/m2 q3wk (arm A) versus 260 mg/m2 q2wk with filgrastim (arm B) versus 130 mg/m2 weekly uninterrupted, all with bev (15 mg/kg q3wk arm A, 10 mg/kg q2wk arms B and C). Pts were required to have measurable, HER-2-negative MBC and no prior chemotherapy for MBC. The primary endpoints were response rate and toxicity. Results: Accrual is complete, with 25% of pts still on study as of December 1, 2008. Of 208 pts randomized, 202 (72 arm A, 54 arm B, 76 arm C) were treated, with balanced demographics and baseline characteristics. The median age was 56 (range 29–85). 89% had visceral disease and 61% had prior neo-adjuvant or adjuvant chemotherapy. No significant differences in confirmed complete and partial response rates were noted (A: 42%, B: 42%, C: 41%). TTP was longer in arm C (9.2 months) versus both arms B (6.4 months) and A (7.7 months), overall p = 0.028. As per protocol-specified stopping rule, arm B was closed early due to unacceptable safety profile with significantly more grade ≥ 2 fatigue (B:57%, A: 39%, C:39%, p = 0.048) and bone pain (B: 19%, A: 10%, C:4%, p = 0.024). Neurotoxicity grade ≥ 2 was equivalent across all 3 arms (50%); febrile neutropenia occurred in <2% of pts in all arms. Arm C had significantly less arthralgia, myalgia, and nausea compared with arms A and B. Conclusions: Significant antitumor activity was observed in all arms. Weekly nab-P with bev (Arm C) resulted in a significantly longer TTP. Weekly nab-P with bev (Arm C) appears to have the highest therapeutic index, however sensory neuropathy is limiting, suggesting a 3 week on/1 week off schedule could be preferable and should be studied comparatively.

[Table: see text]

Dose-dense (DD) doxorubicin and cyclophosphamide (AC) followed by weekly paclitaxel (P) with trastuzumab (T) and lapatinib (L) in HER2/neu-positive breast cancer is not feasible due to excessive diarrhea: updated results

Abstract #2108

Background: DD q 2 weekly (w) AC → P + T x 1 year (y) has an acceptable safely profile w/ congestive heart failure (CHF) rate of 1/70 pts (Dang, JCO 2008). Lapatinib (L) is effective in HER2 (+) BC. We conducted a pilot study of dd AC → w P + T + L to determine its feasibility and cardiac safety.&#x2028; Methods: Enrolled pts had HER2 (+) BC; LVEF &gt; 50%. Rx consisted of AC at 60/600 mg/m2 x 4 q 2 w (w/ pegfilgrastim 6 mg day 2) → P at 80 mg/m2 x 12 q w + T x 1 y; L (1000 mg daily beginning w/ P + T and continued x 1 y). MUGA is obtained at baseline and at months (mo) 2, 6, 9, and 18. Rx is considered feasible if 1) &gt; 80% pts can complete the PTL phase without a dose delay or reduction and 2) the cardiac event rate (CHF or cardiac death) is &lt; 4%. Pts can remain on-Rx w/ one dose reduction of L (1000 mg → 750 mg) for a G 3 event or &lt; G 3 toxicity (unacceptable).&#x2028; Results: From March 2007 to April 2008, we enrolled 95 pts. Median (med) age was 45 years (range, 28-73). At a med follow-up of 7 months, 90 are evaluable. Of the 90 pts, 34 (37%) withdrew from study during the PTL phase; 29 for a 2nd event of G 3 or unacceptable &lt; G 3 toxicities (15 G 3 diarrhea, 4 G 1/2 diarrhea, 1 G 3 rash, 2 G 2 rash, 1 G 3 dyspnea and also had G 3 diarrhea, 1 G 3 ↑QTc also had G 3 diarrhea, 1 G 3 ↑ALT also had G 3 diarrhea, 1 G 3 paronychia, 1 G 3 pneumonitis, 1 asymptomatic LVEF ↓, 1 myocarditis) and 5 for other reasons (2 personal reason, 1 PCP pneumonia, 1 progression, 1 P hypersensitivity). Overall, 25/90 (27%) pts had G 3 diarrhea and 31/90 (34%) pts required a dose reduction of lapatinib. Med LVEF at baseline is 67% (N=95), at mo 2 is 68% (N=90), at mo 6 is 65% (N=53), and mo 9 is 65% (N=28). To date there are no patient drop-outs due to significant LVEF declines after dd AC; one patient dropped during PTL out due to an asymptomatic LVEF decline.&#x2028; Discussion: L at 1000 mg/day is not feasible combined w/ weekly P and T by protocol stipulation (&gt; 20% pts required L dose reduction) primarily due to excessive G 3 diarrhea. These results have led to the modification of Design 2 (Arm D) of ALTTO. We will report updated results.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2108.

Pharmacokinetics and tolerability of exemestane in combination with raloxifene in postmenopausal women with a history of breast cancer

PURPOSE

Raloxifene is a second-generation selective estrogen receptor modulator that reduces the incidence of breast cancer in postmenopausal women. Exemestane, a steroidal aromatase inhibitor, decreases contralateral new breast cancers in postmenopausal women when taken in the adjuvant setting. Preclinical evidence suggests a rationale for coadministration of these agents to achieve complete estrogen blockade.

EXPERIMENTAL DESIGN

We tested the safety and tolerability of combination exemestane and raloxifene in 11 postmenopausal women with a history of hormone receptor-negative breast cancer. Patients were randomized to either raloxifene (60 mg PO daily) or exemestane (25 mg PO daily) for 2 weeks. Patients then initiated combination therapy at the same dose levels for a minimum of 1 year. Pharmacokinetic and pharmacodynamic data for plasma estrogens, raloxifene, exemestane, and their metabolites were collected at the end of single-agent therapy and during combination therapy.

RESULTS

Plasma concentration-time profiles for each drug were unchanged with monotherapy versus combination therapy. Raloxifene did not affect plasma estrogen levels. Plasma estrogen concentrations were suppressed below the lower limit of detection by exemestane as monotherapy and when administered in combination with raloxifene. The most common adverse events of any grade included arthralgias, hot flashes, vaginal dryness and myalgias.

CONCLUSIONS

In this small study, coadministration of raloxifene and exemestane did not affect the pharmacokinetics or pharmacodynamics of either agent to a significant degree in postmenopausal women. The combination of estrogen receptor blockade and suppression of estrogen synthesis is well tolerated and warrants further investigation.

Phase I study of a novel capecitabine schedule based on Norton-Simon mathematical modeling

1045

Background: We have previously described a mathematical method to optimize chemotherapy dose and schedule (Norton et al, AACR 2005). Capecitabine (C) has activity in breast cancer when conventionally dosed for 14 days (d) q3 weeks (14/7). However, the predicted optimal dosing schedule for C using our model is 7d followed by a 7d rest (biweekly, 7/7). We tested this hypothesis in a Phase I/II study described below. Methods: Eligible patients (pts) have measurable, metastatic breast cancer (MBC), ECOG performance status (PS) =2 and normal organ function. There is no limit to number of prior chemotherapy (CRx) regimens. Pts with prior fluoropyrimidine for MBC are excluded. HER2+ pts must not be candidates for trastuzumab. C is given in divided daily doses for 7d followed by a 7d rest. A standard “3+3” dose escalation scheme employs flat dosing which begins at 1,500mg BID and increases by 500mg/dose level. Primary endpoint is the maximum tolerated dose (MTD), defined as the highest dose for which the incidence of dose-limiting toxicity (DLT) is <33%. Results: 19 pts are now accrued; 17 pts have been treated, 2 withdrew prior to receiving C. Medians: age 47 y (range 34–62 y) and ECOG PS 0 (range 0–2). Sites of MBC: bone 8, viscera 16, soft tissue 11. ER/PR+ 11. HER2+ or unknown 2. Prior adjuvant tx: CRx 17, hormone tx 10. Six pts had adjuvant fluoropyrimidine-based tx. Three pts had 1 prior CRx for MBC; 12 pts received first-line hormone tx for MBC. Fifteen pts had prior anthracycline and taxane. Treatment-related toxicities after a median of 4 cycles (range 1–10) are shown in the table . The MTD has not been reached. Pts continue accrual to the 2500mg/2500mg dose level. Conclusions: Capecitabine 7/7 is well tolerated and allows for safe delivery of higher daily doses than routinely used in practice, as predicted by the mathematical model. Capecitabine 7/7 will be tested in a Phase II program at MSKCC in combination with targeted agents.

[Table: see text]

No significant financial relationships to disclose.

Phase II study of weekly nanoparticle paclitaxel (ABI-007), carboplatin and trastuzumab as first-line therapy of HER2-positive metastatic breast cancer

10650

Background: The combination of carboplatin (C), paclitaxel (P) and trastuzumab (T) is active in HER2+ metastatic breast cancer (MBC) (Robert N et al. Proc ASCO 2003), and safer with weekly administration of all 3 agents (Perez E et al. Proc ASCO 2004). The superiority of nanoparticle paclitaxel (Abraxane, AB) over Cremophor-based paclitaxel (Gradishar W et al. JCO 2005), and the efficacy and safety of weekly AB in MBC (Blum J et al. Proc ASCO 2005) motivated us to conduct this study. Materials/Methods: To date 10 of 50 planned patients (pts) with measurable, HER2+ MBC have entered. After we established the safety of AB at 75 mg/m2 on days 1, 8, and 15 every 28 days (n = 4 pts), all subsequent pts received AB at 100 mg/m2. C was dosed at AUC = 2 on the same schedule, and T was weekly at 2 mg/kg without interruption, after a 4 mg/kg load. Initially, no prophylactic anti-allergy medication was given. Treatment is until disease progression (PD) or prohibitive toxicity. Pts without PD at 6 months may opt to continue T alone. Median age: 42 yrs (29–66), ECOG PS 0/1 (70/30%); 6 pts had prior adjuvant chemotherapy; 1 with anthracycline (A) and 4 with A + taxane (> 1 yr prior). Results: 68 cycles have been delivered to date (median: 8, range 1–9). Dose reductions of AB and C have been necessary in 4 pts (to 80 mg/m2 and AUC of 1.5 weekly), with delays in 4 pts. 3 pts had hypersensitivity reactions (HSR) to C and continued protocol therapy without C (n = 2) or with C and the addition of anti-HSR premeds (n = 1). Grade ¾ toxicities include neutropenia (44/11%) with 1 episode of febrile neutropenia. Grade ¾ anemia or thrombocytopenia has not occurred. Grade ¾ non-hematologic toxicity has been rare: 1 instance of grade 3 neuropathy (2 pts with grade 2). 7 partial responses have been observed in the first 9 evaluable pts (78%, 95% CI 44–93%), in liver, lung, bone and soft tissue sites, including 4 pts with prior adjuvant taxane. The median time to PD is not reached at 9.9+ months (7.3–9.9+). Accrual continues as the trial expands to additional study sites. Conclusions: The weekly administration of AB, C, and T demonstrates promising preliminary efficacy as 1st-line treatment for HER2+ MBC. With the exception of HSRs due to weekly C, a very favorable toxicity profile is observed.

[Table: see text]

Updated cardiac safety results of dose-dense (DD) doxorubicin and cyclophosphamide (AC) followed by paclitaxel (T) with trastuzumab (H) in HER2/neu overexpressed/amplified breast cancer (BCA)

582

Background: DD q 2 weekly (w) AC → T is superior to conventionally scheduled (cs) AC → T and safe w/long follow-up (Hudis et al, SABCS 2005). With q 3 wk AC, adjuvant (adj) H is safe and effective (Romond et al and Perez et al, NEJM 2005). We therefore tested DD q 2 w AC → T + H × 1 year (y) as adj treatment (Rx) of patients (pts) with HER2/neu (+) BCA to determine cardiac safety. Based on the reported cardiac event (CE) rate of ≤ 4% in the randomized trials using cs chemotherapy (CRx) + H, we evaluated DD q 2 w AC → T + H with a 1° endpoint of cardiac safety defined as discontinuation (DC) of H due to 1) cardiac death or 2) congestive heart failure (CHF). The 2° endpoint is time to recurrence and overall survival. Methods: Pts with HER2/Neu IHC 3+ or FISH-amplified BCA were enrolled, regardless of tumor size or nodal status. Rx consisted of AC at 60/600 mg/m2 × 4 → T at 175 mg/m2 × 4 q 2 w w/pegfilgrastim 6 mg on d 2 + H × 1 y. Multi-gated radionuclide angiography scan (MUGA) is obtained at baseline and at months (mo) 2 (after AC × 4), 6 (after T × 4), 9, and 18. Pts w/baseline LVEF of ≥ 55% and w/o cardiac illnesses are eligible. Pts w/significant (sig) asymptomatic (asx) LVEF ↓ after DD AC based on mo 2 MUGA did not receive H, and pts w/sig asx LVEF ↓ during H had it DC’d. If the CE rate is > 4%, Rx is deemed not feasible. Results: From January 4, 2005 to November 1, 2005, 70 pts were enrolled. Median (med) age is 49 years (range, 27–72). Forty one of 70 pts (60%) had node (+) BC and 27/70 pts (40%) had (-) nodes. Med baseline LVEF is 68% (range, 55%-81%). As of January 9, 2005, all pts had mo 2 MUGA after DD AC and there is no sig LVEF ↓ and the med LVEF is 67% (range, 58%-79%). To date 39 pts had mo 6 MUGA w/med LVEF of 66% (range, 56%-75%) and one pt had a sig asx LVEF ↓ from baseline of 74% to 56%; H was DC’d. Twenty-three pts had mo 9 MUGA w/a med LVEF of 64% (range, 57%-69%). One patient had clinical CHF at mo 4 w/EF of 45% and improved sig w/cardiac medications. One had pneumonitis during radiation (RT). One had atrial fibrillation w/pericarditis after completion of RT. Discussion: DD AC → T + H appears to have an acceptable cardiac toxicity profile w/1/70 pts having a CE. Updated cardiac safety data will be presented.

[Table: see text]

Study participants’ perceptions of the process and impact of receiving results of N9831

518

Background: There has been growing interest in providing clinical trial participants with study results. We sought to evaluate the process of sharing results from a large cooperative group trial in an effort to guide clinicians and clinical investigators. Methods: We mailed surveys to a subset of women who participated in NCCTG 9831, Phase III Trial of Adjuvant Chemotherapy with or without Trastuzumab for Women with HER2+ Breast Cancer, after the preliminary study results were mailed to participants. Surveys were sent to all trial participants enrolled through 9 CALGB/ECOG institutions. Results: Of 228 surveys sent, 160 (70%) have been returned. Average age of respondents was 51 years (range 26–76); 84% were white; 61% were college graduates; 4% reported recurrent disease. Women reported receiving results by mail (84%), from a health care provider in person or by phone (43%), and/or from the media (47%); 2% reported that they were not informed of the results. 29% heard the results first from the media; 27% first heard by mail. 35% of women might have preferred to be offered results, with the option of not receiving them, but only 4% of women indicated that they would have declined results had they been offered first. 89% of women found the results information easy to understand; 69% correctly interpreted the results of the study; 31% either had an incorrect interpretation or were unsure of the findings. 81% of women were satisfied with how results were shared; 63% of women felt that learning results had an impact on their lives, 24% were more anxious after learning the results; 36% were less anxious. Multivariable analyses evaluating factors associated with greater satisfaction and increased anxiety will be presented. Conclusions: Sharing results is met with overwhelmingly favorable responses from patients, although a substantial proportion of patients may not initially understand the findings. Some patients desire to be offered results first, but few would decline them. The potential for increased anxiety should be considered, and psychosocial support may be required by some. A plan to share results should be routinely and prospectively included in the design of clinical trials. (Supported in part by an ASCO Career Development Award (AHP)

No significant financial relationships to disclose.

Apparent diffusion coefficients for differentiation of cerebellar tumors in children

BACKGROUND AND PURPOSE

Diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps provide information at MR imaging that may reflect cell attenuation and integrity. We hypothesized that cerebellar tumors in children can be differentiated by their ADC values.

METHODS

Brain MR imaging studies that included ADC maps were retrospectively reviewed in 32 patients with histologically proved cerebellar neoplasm. There were 17 juvenile pilocytic astrocytomas (JPA), 8 medulloblastomas, 5 ependymomas, and 2 rhabdoid (atypical teratoid/rhabdoid tumor [AT/RT]) tumors. Absolute ADC values of contrast-enhancing solid tumor regions and ADC ratios (ADC of solid tumor to ADC of normal-appearing white matter) were compared with the histologic diagnosis. ADC values and ratios of JPAs, medulloblastomas, and ependymomas were compared by using a 2-tailed t test and one-way analysis of variance (ANOVA).

RESULTS

ADC values were significantly higher in pilocytic astrocytomas (1.65 +/- 0.27) (mean +/- SD) than in ependymomas (1.10 +/- 0.11) (P = .0003) and medulloblastomas (0.66 +/- 0.15) (P < .0001). Ependymomas demonstrated significantly higher ADC values than medulloblastomas (P = .0005). The observed differences were statistically significant on ANOVA (P < .001). ADC ratios were also significantly different among these 3 tumor types. AT/RT ADC values were similar to medulloblastoma. The range of ADC values and ratios within JPAs and ependymomas did not overlap with that of medulloblastomas.

CONCLUSION

Assessment of ADC values of enhancing solid tumor is a simple and reliable technique for preoperative differentiation of cerebellar tumors in pediatric patients. Our cutoff values of >1.4 x 10(3) mm(2)/s for JPA and <0.9 x 10(3) mm(2)/s for medulloblastoma were 100% specific.

Comparative results of Doppler sonography after TIPS using covered and bare stents

OBJECTIVE

Our purpose was to evaluate the role of sonography in the early follow-up of patients with a covered transjugular intrahepatic portosystemic shunt (TIPS).

CONCLUSION

Routine baseline Doppler sonography should occur 7-14 days after shunt placement unless malfunction or procedural complications are suspected.

Influence of the randomized trials, AFFIRM and RACE, on the management of atrial fibrillation in two University Medical Centers

The results of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) and the Rate Control Versus Electrical Cardioversion for Persistent Atrial Fibrillation (RACE) study were presented in March 2002. These large studies showed no benefit of a rhythm-control strategy over a rate-control strategy in managing atrial fibrillation (AF). Cardioversion and atrioventricular junctional ablation are forms of rhythm control and rate control, respectively. The numbers of cardioversions and atrioventricular junctional ablations performed at the University of Virginia and the Medical College of Virginia during the 52 months before AFFIRM and RACE results were released and the 21 months afterward were compared. From January 1998 to March 2002, monthly averages of 31 +/- 8 elective cardioversions and 6 +/- 3 atrioventricular junctional ablations were performed; from April 2002 to December 2003, the monthly averages were 21 +/- 6 cardioversions (p = 0.001) and 9 +/- 3 ablations (p = 0.001). AF management changed at these institutions shortly after the RACE and AFFIRM results were released.

Cross-clade HIV-1 neutralization by an antibody fragment from a lupus phage display library

A single-chain fragment containing antibody V domains (scFv) isolated from a lupus antibody library displayed the ability to bind gp120 and the conserved gp120 determinant composed of residues 421-436. The scFv neutralized R5 and X4-dependent HIV-1 strains from clades B, C, and D. The lupus repertoire may be useful as a source of neutralizing antibodies to HIV.