Sacituzumab govitecan, a Trop-2-directed antibody-drug conjugate, for patients with epithelial cancer: final safety and efficacy results from the phase I/II IMMU-132-01 basket trial

BACKGROUND

Sacituzumab govitecan (SG), a trophoblast cell surface antigen-2 (Trop-2)-directed antibody-drug conjugate, has demonstrated antitumor efficacy and acceptable tolerability in a phase I/II multicenter trial (NCT01631552) in patients with advanced epithelial cancers. This report summarizes the safety data from the overall safety population (OSP) and efficacy data, including additional disease cohorts not published previously.

PATIENTS AND METHODS

Patients with refractory metastatic epithelial cancers received intravenous SG (8, 10, 12, or 18 mg/kg) on days 1 and 8 of 21-day cycles until disease progression or unacceptable toxicity. Endpoints for the OSP included safety and pharmacokinetic parameters with investigator-evaluated objective response rate (ORR per RECIST 1.1), duration of response, clinical benefit rate, progression-free survival, and overall survival evaluated for cohorts (n > 10 patients) of small-cell lung, colorectal, esophageal, endometrial, pancreatic ductal adenocarcinoma, and castrate-resistant prostate cancer.

RESULTS

In the OSP (n = 495, median age 61 years, 68% female; UGT1A1∗28 homozygous, n = 46; 9.3%), 41 (8.3%) permanently discontinued treatment due to adverse events (AEs). Most common treatment-related AEs were nausea (62.6%), diarrhea (56.2%), fatigue (48.3%), alopecia (40.4%), and neutropenia (57.8%). Most common treatment-related serious AEs (n = 75; 15.2%) were febrile neutropenia (4.0%) and diarrhea (2.8%). Grade ≥3 neutropenia and febrile neutropenia occurred in 42.4% and 5.3% of patients, respectively. Neutropenia (all grades) was numerically more frequent in UGT1A1∗28 homozygotes (28/46; 60.9%) than heterozygotes (69/180; 38.3%) or UGT1A1∗1 wild type (59/177; 33.3%). There was one treatment-related death due to an AE of aspiration pneumonia. Partial responses were seen in endometrial cancer (4/18, 22.2% ORR) and small-cell lung cancer (11/62, 17.7% ORR), and one castrate-resistant prostate cancer patient had a complete response (n = 1/11; 9.1% ORR).

CONCLUSIONS

SG demonstrated a toxicity profile consistent with previous published reports. Efficacy was seen in several cancer cohorts, which validates Trop-2 as a broad target in solid tumors.

Abstract P1-11-15: Chemotherapy-induced peripheral neuropathy in breast cancer survivors: Comparison of objective and subjective measures

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a common, potentially debilitating, and dose-limiting side effect experienced by breast cancer survivors. CIPN encompasses symptoms such as pain, numbness, and tingling, which can be measured subjectively by patient-reported outcomes (PRO), or objectively by quantitative sensory testing (QST); however, little is known how QST correlates with symptom profiles measured by PRO.

Methods: We conducted a cross-sectional analysis using baseline data of two ongoing clinical trials of breast cancer survivors who experienced moderate to severe CIPN defined by pain, numbness, or tingling ratings of four or greater on a numeric rating scale (NRS) after chemotherapy completion for at least three months. PRO measures of CIPN symptoms included Neuropathic Pain Scale (NPS) and Functional Assessment of Cancer Therapy-Gynecologic Oncology Group/Neurotoxicity subscale (FACT/GOG-Ntx). QST included tactile threshold (TT) measured by Von Frey's filaments, and vibration threshold (VT) measured by biothesiometer. We ran a Spearman correlation to assess the relationship between the subjective measures (NPS and FACT/GOG-Ntx) and objective measures (TT and VT QST).

Results: We included 52 sets of baseline data on 50 unique patients; two patients were enrolled in both trials at different times. Mean age was 61 years (SD 10) and 66% were white. The mean NRS pain score was 3.9 (SD 2.8), numbness 5.7 (SD 2.2), and tingling 4.3 (SD 2.8) on a 0-10 scale. The mean NPS total score was 39.2 (SD 23.1) on a 0-100 scale, and FACT/GOG-Ntx was 26.2 (SD 6.8) on a 0-44 scale. High scores on NRS and NPS and low scores on FACT/GOG-Ntx signify more severe CIPN symptoms. See Table 1 for a summary of the correlation between two questions on FACT/GOG-Ntx on tingling/numbness in hands and feet, and NPS total score with QST. A moderate correlation was observed between FACT/GOG-Ntx and QST results, suggesting patient-reported hand and foot numbness or tingling is associated with decreased hand and foot tactile and vibration perception. NPS was positively correlated with tactile perception for the hand and foot, but not with vibration perception.

Table 1.Correlation between objective and subjective measures of CIPN Tactile QSTVibration QST HandFeetHandFeetFACT/GOG-Ntx-0.33 (P=0.018)-0.28 (P=0.045)-0.37 (P=0.008)-0.40 (P=0.0034)NPS0.34 (P=0.015)0.32 (P=0.022)0.22 (P=0.12)0.03 (P=0.81)

Conclusions: A mild to moderate correlation was observed between subjective and objective measurements of CIPN. As CIPN presents a diverse range of symptoms, better quantifying the subjective and objective measures of CIPN can help incorporate these tools in observational and intervention trials. Understanding the correlation between PRO and QST can help establish QST as a reliable objective measurement of CIPN symptoms, and enable targeted interventions to alleviate CIPN symptoms.

Citation Format: Bao T, Kwon A, Piulson L, Chen P, Li Q, Patil S, Seidman A, Blinder V, Vahdat L, Zhi WI, Mao JJ. Chemotherapy-induced peripheral neuropathy in breast cancer survivors: Comparison of objective and subjective measures [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 P1-11-15.

Abstract PD1-02: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Cortes J, Martin M, Pernas S, Gomez Pardo P, Lopez-Tarruella S, Gil-Martin M, Manso L, Ciruelos E, Perez-Fidalgo JA, Hernando C, Ademuyiwa FO, Weilbaecher K, Mayer I, Pluard TJ, Martinez Garcia M, Vahdat L, Wach A, Barker D, Romagnoli B, Kaufman PA. Withdrawn [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 PD1-02.

Abstract P3-15-03: Clinical benefit, toxicity, and cost of metastatic breast cancer drug therapies: Visualizing randomized and non-randomized evidence

Background: Given the rapidly expanding size of the clinical trial literature for metastatic breast cancer (MBC) clinical trials, oncologists need tools that enable them to efficiently review the settings and results of previous studies.

Methods: We searched the Cochrane Central Register of Controlled Trials and PubMed to identify clinical trials testing MBC drug therapies. Key eligibility criteria included >90% of patients enrolled in trial having MBC, therapeutic clinical trials, and Phase II or III studies with at least 10 patients at a dosage level. From each study, we extracted information about clinical benefit and toxicity of drug therapies, and we further estimated the costs of all drug therapies. We built a web-based visualization tool that presents the results of all studies testing a given drug combination, stratified based on patients' receptor statuses and prior exposure to therapy. The tool presents both aggregate and study-level results, and reports both unadjusted study results and standardized results based on key patient characteristics in the study populations.

Results: We included 1,783 studies containing 2,549 treatment arms and 170,515 patients in the visualization tool. The tool reports information on 77 HER-2-directed therapies, 101 hormonal therapies, and 675 undirected therapies. The visualization tool has been made publicly accessible for patients and doctors to access at http://cancertrials.info.

Discussion: We believe this tool will make literature reviews significantly more efficient for oncologists, enabling them to better leverage insights from the clinical trial literature when making treatment decisions.

Citation Format: Silberholz J, Vahdat L, Bertsimas D. Clinical benefit, toxicity, and cost of metastatic breast cancer drug therapies: Visualizing randomized and non-randomized evidence [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 P3-15-03.

Abstract P3-02-02: Targeting the tumor microenvironment: A phase II study of copper-depletion using tetrathiomolybdate (TM) in patients (pts) with breast cancer (BC) at high risk for recurrence

Background: Bone marrow derived VEGFR2+ endothelial progenitor cells (EPCs) and copper-dependent pathways, including lysyl oxidase (LOX), are critical components to remodeling the tumor microenvironment and establishing the pre-metastatic niche. In preclinical models, it has been well established that copper depletion (CD) inhibits tumor progression. We hypothesized that TM-associated CD would reduce EPCs and other copper dependent processes in the pre-metastatic niche in BC pts at high risk for relapse. We investigated the relationship between CD and its effect on EPCs and other components of the tumor microenvironment including LOX, an enzyme critical for cross-linkage of collagen and priming the pre-metastatic niche.

Methods: In this single arm, phase II study, BC pts at high risk for recurrence, defined as node+ triple negative (TN), stage 3 and 4 with no evidence of disease (NED) were enrolled on a trial of CD with TM. Pts received oral TM to maintain ceruloplasmin (Cp) between 5-17 mg/dl for 2 years on the primary study. The primary endpoint was change in EPCs measured by flow cytometry before and during treatment with TM. Secondary endpoints included tolerability, safety and effect of copper depletion on other markers including LOX, quantified by ELISA.

Results: We enrolled 75 pts. The study treatment duration was 24 cycles (each cycle is 28 days). Over 2200 cycles have been administered. The median age is 51 (range 29-66). 45 pts have Stage 2/3 BC and 30 are Stage 4 NED. TNBC pts represent 48%, and 40% of pts are Stage 4 NED. Median Cp level decreased from 28 at baseline to 15.5 (p<0.0001) after one cycle. Copper depletion was most efficient in TNBC, with 91% achieving a target CP within 4 weeks. TM was well tolerated and the only grade 3/4 toxicities were reversible neutropenia (3.2%) and anemia (0.0005%). CD was associated with a significant decrease in EPCs (p=0.0014) and LOX (p<0.001). At a median follow-up of 5.4 years, the PFS for all 75 pts from the start of TM treatment was 71%, including a PFS of 90% for all stage 2/3 pts with TNBC. The overall survival of all patients enrolled in the trial is 86%. Relapse after two years is a rare event. Conclusions: TM is safe, well tolerated and appears to affect multiple copper dependent biologic processes in the tumor microenvironment known to be important for tumor progression. This seems to be most striking in TNBC. We believe, further phase III trials in a high risk for relapse population are warranted.

Citation Format: Nackos E, Willis A, Kornhauser N, Ward M, Andreopoulou E, Cigler T, Moore A, Fitzpatrick V, Cobham M, Schneider S, Wiener A, Guillaume-Abraham J, Warren JD, Rubinchik A, Lane M, Mittal V, Vahdat L. Targeting the tumor microenvironment: A phase II study of copper-depletion using tetrathiomolybdate (TM) in patients (pts) with breast cancer (BC) at high risk for recurrence. [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 P3-02-02.

Abstract P2-16-23: The ENCHANT-1 trial (NCT01677455): An open label multicenter phase 2 proof of concept study evaluating first line ganetespib monotherapy in women with metastatic HER2 positive or triple negative breast cancer (TNBC)

Background: Hsp90 is a molecular chaperone protein required for the stabilization and activation of many proteins, referred to as Hsp90 ‘clients’, such as HER2, HIF1-a, EGFR, ER, PI3K, AKT, P53 and VEGFR. The drug candidate, ganetespib is a novel triazolone inhibitor of Hsp90, with over 700 patients treated to date. Ganetespib has shown activity in preclinical models of HER2+, ER+/PR+ and TNBC. Early clinical trials documented ganetespib single agent activity in heavily pretreated HER2+ and TNBC patients. Ganetespib has been well tolerated in clinical trials with a favorable safety profile. This efficacy-screening study is designed to provide further evidence of ganetespib activity and identify potentially predictive biomarkers in metastatic breast cancer (BC).

Methods: The ENCHANT-1 Trial is an international, first-line 2-cohort Phase 2 study in BC patients: Cohort A, HER2 amplified (n = 35), and Cohort B, TNBC (n = 35). Patients who present with previously untreated metastatic disease are eligible for treatment with ganetespib at 150 mg/m2 twice weekly on 3 out of 4 wks, for a total of up to 12 wks. Primary endpoint: ORR assessed using RECIST1.1 criteria. Key secondary endpoints include metabolic response as assessed by PET/CT at wk 3 utilizing modified EORTC criteria. Disease progression (PD) at wk 3 by PET imaging indicates discontinuation of study therapy, and is performed to quickly offer patients with metabolic PD a standard of care treatment.

The study is designed as Simon 2-stage requiring at least one OR in 15 patients for the respective cohort to expand to 35 patients. A Steering Committee is established to oversee the overall study and review the interim results.

Results: The study was initiated in 23 centers globally. At the time of submission, a total of 17 patients had been enrolled; TNBC (n = 15) and HER2 (n = 2). Here we report the interim analysis in the TNBC cohort. The median age was 54 years (range 30 -77) with ECOG PS 0 (n = 7/15). Most patients (n = 9) presented with de novo metastatic disease. 5 patients were not evaluable for PET assessment (3 had not yet reached wk 3 and 2 withdrawn before wk 3 for clinical progression), and 9 patients were not evaluable for objective response at wk 6 (3 withdrawn before or at wk 3 for clinical progression and 6 had not yet reached wk 6 evaluation). In the 10 patients with evaluable PET imaging, 9 patients achieved metabolic (m) response (2 mPR, 4 mSD with dominant tumor shrinkage and 3 SD) and one patient with mPD. In the 6 patients evaluable for OR at wk 6, one patient achieved PR, 2 SD and 3 PD. Treatment with ganetespib was well tolerated; the most common AEs were mild or moderate diarrhea (8/15, 53%), fatigue (5/15, 33%), decreased appetite (4/15, 27%), insomnia (4/15, 27%), and nausea (4/15, 27%).

Conclusion: Ganetespib single agent was generally well tolerated and showed anti-tumor activity TNBC patients as early as 3 weeks following treatment. PET seems to be a good tool to screen antitumor activity of new agents in early settings rather that in heavily pretreated patients. The TNBC cohort has met the protocol criteria for proceeding to stage 2.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-23.

Abstract P3-13-05: Eribulin mesylate as first-line therapy for locally recurrent or metastatic HER2-negative breast cancer: Results of a phase 2, multicenter, single-arm study

Background: Eribulin mesylate is a novel nontaxane microtubule dynamics inhibitor that is approved for treatment of metastatic breast cancer (MBC) in patients who have previously received at least two chemotherapeutic regimens for MBC. We present final data from a phase 2 study that evaluated the efficacy and safety of eribulin as first-line therapy for HER2-negative (HER2-) MBC.

Methods: Patients with measureable HER2- locally recurrent or MBC with ≥12 months since prior neoadjuvant or adjuvant chemotherapy received eribulin mesylate 1.4 mg/m2 IV on days 1 and 8 of each 3-week cycle. Endpoints included objective response rate (ORR) (primary), safety, progression-free survival (PFS), time to response (TTR), and duration of response (DOR). Tumor assessments were conducted every 6 weeks for the first 6 cycles and every 6-12 weeks thereafter per RECIST 1.1.

Results: Fifty-six patients enrolled and received eribulin. Patients had a median age of 56 years (range 31-85); 32 (57%) had an ECOG status of 0; 17 (30%) had de novo stage IV; 33 (59%) had prior (neo)adjuvant therapy, including anthracycline and/or taxane (A/T) chemotherapy. Thirty-nine patients (70%) had visceral disease (45% liver, 32% lung); 41(73%) had estrogen receptor-positive (ER+) disease and 12 (21%) had triple negative (TN) disease. Thirty-two patients (57%) completed at least 6 cycles of treatment; among the 24 patients who completed fewer than 6 cycles, reasons for not completing were progressive disease (PD; n = 18), adverse events (AEs; n = 3) and patient choice (n = 3). The median number of cycles delivered was 7 (range 1-39); 6 patients (11%) received treatment for ≥12 months. Overall ORR was 27%, with median TTR of 1.4 months and median DOR of 7.4 months; stable disease (SD) rate was 48% (Table 1). Median PFS was 6.8 months. Thirty-five patients (63%) had grade 3/4 treatment-related AEs (Table 2). Treatment-related serious AEs occurred in 5 (9%) patients: neutropenia (5%), febrile neutropenia (5%), and leukopenia (2%).

Conclusions: The results of this study suggest that first-line eribulin has antitumor activity in ER+/HER2- and TN MBC with safety consistent with the known profile. Further exploration of this treatment as part of earlier lines of breast cancer therapy, including neo/adjuvant, is warranted.

Table 1. Summary of EfficacyEfficacyEribulin-treated patients N = 56ORR, n (%)15 (27)CR0PR15 (27)SD27 (48)PD12 (21)Clinical benefit rate (ORR + ≥6 mo SD)27 (48)Median months (95% CI) TTR1.4 (1.2, 2.7)DOR7.4 (4.7, NE)PFS6.8 (4.4, 7.4)NE, not estimable

Table 2. Treatment-Related AEsAE (N = 56)All events (%)Grade 3/4 (%)Leading to study drug withdrawal1111Leading to dose reduction3427Common AEs (≥25%)  Alopecia820Neutropenia7050Fatigue572Peripheral neuropathy5420Nausea460Anemia364Leukopenia3018Constipation270

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-13-05.

Abstract P2-16-05: Efficacy of ABT-888 (veliparib) in patients with BRCA-associated breast cancer

Background: The potential for exploiting BRCA deficiencies with DNA repair inhibitors has both pre-clinical and clinical support. ABT-888 (veliparib), a DNA repair inhibitor initially thought to target Poly(ADP-Ribose) Polymerases (PARP), has demonstrated in vitro inhibition of BRCA1 and BRCA2 deficient mouse embryonic stell cells, with a larger effect on BRCA1 cells. We report on the pre-planned interim analysis of the efficacy of single agent veliparib in patients with either BRCA1 or BRCA2-associated stage IV breast cancer. Methods: BRCA 1 or 2 carrier patients with stage IV breast cancer, with measurable disease, without prior exposure to a PARP inhibitor or a platinum compound in the metastatic setting, were eligible. Velapirib was administered orally, at doses of 400 mg twice daily. Dose adjustments based on toxicity were permitted. Patients progressing on velapirib alone received carboplatin at an AUC of 5, IV, given Q 21 days, and velapirib 150 mg twice daily (the maximum tolerated dose [MTD] of the combination from our completed Phase I study: J Clin Oncol 30, 2012 [suppl; abstr 1024]). Patients were to be accrued from 7 NCI NO1- supported consortia. Initially 10 patients were to be accrued to each stratum (BRCA1 and BRCA2) to provide evidence of single agent activity. If there was sufficient activity to warrant consideration of velapirib as single agent therapy (defined as 2 or more confirmed partial [PR] or better responses out of 10 per stratum), an additional 12 patients would be accrued per stratum. Results: 20 evaluable patients (11 BRCA1 and 9 BRCA2 [1 in screening]) have been accrued, the majority with lung or liver as visceral metastatic sites of disease. Median age (range) is 46 (29-68) years. Tumors from 9 patients were hormone receptor positive. BRCA1 cohort: 4 of 11 patients are off treatment at a median of 2 months (1-4); 1 patient stopped velapirib due to toxicity (grade 2 rash/pruritus, grade 2 vomiting), 3 stopped for progressive disease (one with an unconfirmed PR). Seven patients are still on single agent veliparib with 1 unconfirmed PR, and 1 patient with two evaluations showing stable disease. BRCA2 cohort: 2 patients are off treatment at 2 months for progressive disease, 7 are still on treatment with 1 confirmed PR, and 3 unconfirmed PRs. Data on patients receiving combination of velapirib and carboplatin after progression is too early. Treatment-related toxicity is being updated and has so far been reported from 14 patients: 1 patient had grade 3 fatigue, 1 patient with liver metastasis had both grade 3 alanine aminotransferase elevation and grade 3 abdominal pain. Grade 2 toxicities occurring in more than 1 patient included nausea/vomiting (6 patients), chills (2 patients), and fatigue (2 patients). Conclusion: Velapirib has single agent activity in both BRCA1 and BRCA2-associated stage IV breast cancer patients, and is well-tolerated. Mature response, treatment, and toxicity data will be presented.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-05.

Abstract P4-12-12: Phase 2, multicenter, single-arm study of eribulin mesylate + trastuzumab as first-line therapy for locally recurrent or metastatic HER2-positive breast cancer

Background: Eribulin mesylate, a non-taxane microtubule dynamics inhibitor, has been approved for patients with metastatic breast cancer (MBC) who have previously received ≥2 chemotherapeutic regimens for MBC. We present final data from a phase 2 study that evaluated efficacy and safety of eribulin + trastuzumab as first-line therapy for locally recurrent or metastatic human epidermal growth factor receptor 2 positive (HER2+) BC.

Methods: Patients received eribulin mesylate at 1.4 mg/m2 IV on days 1 and 8 of each 21-day cycle and an initial trastuzumab dose of 8 mg/kg IV on day 1, followed by 6 mg/kg on day 1 of each subsequent cycle. Endpoints include objective response rate (ORR), safety, progression-free survival (PFS), time to response (TTR), and duration of response (DOR). Tumor assessments were conducted every 6 weeks for the first 6 cycles and every 6-12 weeks thereafter per RECIST 1.1.

Results: Fifty-two patients with a median age of 60 years (range 31- 81) were treated; 96% had stage IV disease, 73% had visceral disease, and 48% had liver metastases. Thirty one patients had prior neo/adjuvant chemotherapy (11 had prior anthracycline, and 22 had prior taxane). Patients received a median of 10(0, 33) cycles of eribulin and 11(1, 31) cycles of trastuzumab. ORR was 67% with median TTR of 1.3 months and PFS of 11.5 months (Table). The most common (>5%) Grade 3/4 treatment related treatment emergent (TRTE) AEs were neutropenia (n = 20; 38.5%), peripheral neuropathy (n = 14; 26.9%) and febrile neutropenia (n = 4; 7.7%). Serious TRTE AEs occurred in 14 patients and included neutropenia (n = 9; 17.3%), febrile neutropenia (n = 4; 7.7%), and peripheral neuropathy (n = 3; 5.8%). Reasons for discontinuation were AEs (n = 7) and PD (n = 22).

Table. Summary of Efficacy EndpointsEfficacy EndpointsEribulin/Trastuzumab N = 52Objective Response Rate, n (%)35 (67)- Complete Response (CR)2 (4)- Partial Response (PR)33 (64)Stable Disease (SD)15 (29)Progressive Disease (PD)1 (2)Not Evaluable1 (2)Overall Clinical Benefit Rate, n (%)42 (81)Time to First Objective Response, median months (95% CI)1.3 (1.2, 1.4)Duration of Objective Response, median months (95% CI)a11.1 (6.5, 17.8)Progression-Free Survival, median months (95% CI)11.5 (7.3, 13.5)Duration of Stable Disease, median months (95% CI)7.1 (5.2, 13.5)Clinical Benefit Rate = ORR+ ≥6 mo SD; an = 35

Conclusions: This study suggests that the combination of eribulin + trastuzumab first-line therapy for locally recurrent or metastatic HER2+ BC has an acceptable safety profile and results in considerable tumor response with a long DOR. Additional larger studies with this combination are warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-12.

Abstract P1-15-07: Ixabepilone-associated peripheral neuropathy in metastatic breast cancer patients and its effects on the ultrastructure of neurons

Background: Peripheral neuropathy is a dose-limiting toxicity of most microtubule-stabilizing chemotherapeutic agents. Ixabepilone, a semisynthetic analog of the natural epothilone B, has activity in a wide range of tumors including taxane-resistant disease. In this study, we sought to understand the effect of ixabepilone on the development of peripheral neuropathy both clinically and its effect at the ultrastructural level of the peripheral nerves and circulating factors over time. Parallel studies in animal models of neuropathy were performed at the same time (Proc AACR 2010 Abstract 4184).

Methods: This open-label, non-randomized phase II study enrolled 14 patients with metastatic breast cancer. Ixabepilone was administered by 2 schedules: the FDA approved dose of 40 mg/m2 every 3 weeks (q3w) and 16 mg/m2 on day 1, 8, and 15 of a 28-day cycle (weekly). Five controls, 2 with residual taxane-associated peripheral neuropathy and 3 with no prior chemotherapy or peripheral neuropathy, were also accrued. The primary objectives were to characterize the natural history of ixabepilone-associated peripheral neuropathy using the Total Neuropathy Score Clinical (TNSc) assessment tool prior to each cycle and to correlate changes in the ultrastructure of dermal myelinated nerve fibers via a 3 mm punch biopsy of an area 10 cm above the lateral malleolus every 2 cycles with electron microscopy (EM), as well as circulating factors (both inflammatory and neurotrophic) considered to be important in the pathogenesis of chemotherapy-induced peripheral neuropathy. Secondary objectives included progression-free survival (PFS) and non-neurologic toxicity.

Results: 14 patients were enrolled and were equally divided between the 2 schedules of ixabepilone chemotherapy. There were no differences in baseline characteristics between the two groups. Mean age was 54 years (range 32–71). Mean number of previous chemotherapy regimens was 3.5 (range 0–8). 57% of patients had received a taxane in the adjuvant setting and 64% in the metastatic setting. The mean neuropathy score (TNSc) at baseline was 4.6 (range 1–11). At a mean cumulative dose of 185 mg/m2, the TNSc with ixabepilone q3w schedule was 3.7 points higher/worse (95% CI: 2.2–5.3, p = 0.03) than the mean score observed in patients on the weekly schedule. The sensory component was most significantly affected, predominantly numbness. In 3 patients, the chemotherapy schedule was changed from every 3 weeks to weekly due to > grade 2 toxicity at a mean cumulative dose of 107 mg/m2, and TNSc decreased/improved by 2.7 points. PFS in patients on q3w ixabepilone was 133 days (range 28–280) and in patients on weekly ixabepilone was 179 days (range 66–336), nonsignificant. Evaluation of EM and circulating factors is ongoing.

Conclusions: Weekly ixabepilone appears to have a more favorable neurotoxicity profile compared to the standard q3w schedule. Integration of the EM data and the circulating factor data are underway and will be presented. Ixabepilone-associated peripheral neuropathy may improve in patients switched to weekly ixabepilone without compromising efficacy.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-15-07.

Abstract P1-12-02: Results of a phase 2, multicenter, single-arm study of eribulin mesylate as first-line therapy for locally recurrent or metastatic HER2-negative breast cancer

Background: Eribulin mesylate is a novel nontaxane microtubule dynamics inhibitor that is approved in patients (pts) with metastatic breast cancer (MBC) who have previously received at least two chemotherapeutic regimens for MBC. We are reporting a preliminary planned analysis (first 6 cycles of treatment) of a phase 2 study that evaluates efficacy and safety of eribulin as first-line therapy for HER2-negative MBC.

Methods: Pts with measureable HER2-negative locally recurrent or MBC with at least 12 months since prior neoadjuvant or adjuvant chemotherapy received eribulin mesylate at 1.4 mg/m2 IV on days 1 and 8 of each 3-week cycle. Endpoints include objective response rate (ORR) (primary), safety, progression free survival (PFS), time to response (TTR), and duration of response (DOR). Tumor assessments were evaluated every 6 weeks for the first 6 cycles and every 6–12 weeks thereafter per RECIST 1.1.

Results: 54 of 56 enrolled pts had at least 1 post-baseline assessment. The median number of cycles delivered was 7 (range 1,21). Pt characteristics: median age, 56 yrs (range 31–85); ECOG of 0, 32 (57%); 29% had de novo stage IV; 38/56 (68%) had prior neo/adjuvant (45% had anthracycline and 45% taxane, the majority of which were given together). Seventy percent have visceral disease (45% liver, 38% lung); 41 (73%) have estrogen receptor-positive (ER) disease and 12 (21%) have triple negative (TN) (ER−/PR−/HER2−) disease. Objective response data are found in Table 1.

Abstract P5-20-04: Eribulin mesylate + trastuzumab as first-line therapy for locally recurrent or metastatic HER2-positive breast cancer: results from a phase 2, multicenter, single-arm study

Background: Eribulin mesylate, a novel non-taxane microtubule dynamics inhibitor, has been approved for patients with metastatic breast cancer (MBC) who have previously received at least two chemotherapeutic regimens for MBC. This study evaluates efficacy and safety of eribulin + trastuzumab (TRAZ) as first-line therapy for human epidermal growth factor receptor 2 positive (HER2+) locally recurrent or MBC.

Methods: Patients received eribulin mesylate at 1.4 mg/m2 IV on days 1, 8 and TRAZ initial dose of 8 mg/kg IV on day 1 every 21 days, followed by 6 mg/kg on day 1 of each subsequent cycle. For study inclusion, patients could have been previously treated with TRAZ, but at least 12 months should have passed since any prior neoadjuvant or adjuvant chemotherapy was used. Endpoints include objective response rate (ORR) (primary), safety, progression free survival (PFS), time to response (TTR), and duration of response (DOR). Tumor assessments are evaluated every 6 weeks for the first 6 cycles and every 6–12 weeks thereafter per RECIST 1.1.

Results: Updated results presented here as of June 1, 2012; 37 of 52 planned patients have been treated. Patient characteristics are as follows: median age: 58 years (range, 31–81), 70% have luminal subtype, 95% are stage IV disease, and 73% have visceral disease, 46% had prior neo/adjuvant, 22% had prior anthracycline and 32% had prior taxane, 35% had original diagnosis of MBC. Patients received median of 7 (1,20) cycles for eribulin and 9 (1,23) cycles for TRAZ. The most common treatment related AEs are reported in Table 1.

Abstract P6-11-14: Post-hoc safety and tolerability assessment in patients receiving palliative radiation during treatment with eribulin mesylate for metastatic breast cancer

Background: Management of advanced breast cancer frequently includes palliative radiation therapy (RT) and many chemotherapy agents are radiation-sensitizers. We assessed whether the safety profile of eribulin differed between metastatic breast cancer (MBC) patients receiving eribulin alone and those who also received palliative RT.

Methods: Two previous phase 2 and 3 eribulin trials (Studies 211 and 305, respectively) enrolled a total of 794 patients with locally recurrent or MBC who had received 2–5 prior chemotherapy regimens. In both trials eribulin mesylate (1.4 mg/m2) was given on Days 1 and 8 of a 21-day cycle and intercurrent palliative RT was permitted. In this post-hoc analysis, patient-level data were pooled for a descriptive comparison of adverse events (AEs) between the patients who received RT during their study treatment and those who did not. RT delivered within 3 weeks of initiation of eribulin or RT encompassing >30% of marrow was excluded. If palliative RT was utilized on study, the protocol requirements were as follows: indications included bone pain, bronchial obstruction, ulcerating skin lesions; the total field for palliative RT was not to involve >10% of total bone marrow; and the irradiated lesion was not to be used for tumor response assessment. During palliative RT, eribulin treatment was to be delayed and then resumed when the patient had recovered from any RT-associated toxicities.

Results: Of the 794 patients (291 patients in Study 211 and 503 in Study 305) who received eribulin, 44 (5.5%) received palliative RT.

OT3-01-17: Randomized, Double-Blind, Placebo-Controlled Phase II Trial of Low-Dose Metronomic Cyclophosphamide Alone or in Combination with Veliparib (ABT-888) in Chemotherapy-Resistant ER and/or PR-Positive, HER2/neu-Negative Metastatic Breast Cancer: New York Cancer Consortium Trial P8853

Background: Veliparib is an orally available, small molecule inhibitor of poly(ADP-ribose) polymerase (PARP). PARP is an essential nuclear enzyme that plays a role in recognition of DNA damage and facilitation of DNA repair. PARP inhibitors potentiate the cytotoxicity of DNA-damaging agents, including cyclophosphamide (C). The rationale for the proposed trial is as follows: (1) low-dose, continuous metronomic C (50 mp PO daily) has activity in refractory metastatic breast cancer (MBC), (2) PARP is induced by DNA damaging agents, (3) PARP expression is comparable in ER-positive and ER-negative disease, (4) some ER-positive breast cancers exhibit defective homologous recombination pathway repair genes (eg, RAD51 and XRCC3), (5) the PARP inhibitor iniparib appears to be more effective when used in chemotherapy resistant disease. Taken together, these findings suggest that veliparib-C combination may be more effective than metronomic C alone in chemotherapy resistant MBC. Trial design: A randomized Phase II trial design 1:1. S. Blocked randomization will be performed at all participating sites. Patients are randomized to oral C (50mg PO daily) plus either veliparib (60mg PO daily) or matching placebo.

Eligibility criteria:(1) ER- and or PR-positive, HER2−negative MBC, (2) ECOG PS 0–1, (3) at least 2 prior chemotherapy regimens for MBC, including a taxane and capecitabine. 4) at least 1 line of endocrine therapy for metastatic disease (includes relapse while receiving endocrine therapy).

Specific aims: Primary: To determine if the addition of veliparib to metronomic dose C improves median progression free survival (PFS) compared with C alone in patients with ER and/or PR-positive, Her2-negative MBC who progressed on at least two lines of prior chemotherapy and one line of prior endocrine therapy.

Secondary: 1)To determine if the addition veliparib to C chemotherapy improves a) response rate b) clinical benefit rate (defined as objective response plus stable disease for at least 24 weeks from day +1) 2) Survival in patients treated with C alone and C plus veliparib. 3) Adverse event profile in patients treated with C alone and C plus veliparib.

Translational: Exploratory analyses will evaluate whether the macroH2A1.1 and PARP1 expression status in archival paraffin, or veliparib-induced PAR downregulation in peripheral blood mononuclear cells, is predictive of benefit from veliparib.

Statistical methods: The primary endpoint is PFS, and the trial is powered to detect an increase in median PFS from 3 to 6 months (alpha=0.10, beta=0.10), which will require enrollment of 62 eligible patients over 12 months.

Enrollment: The study is active and open to enrollment.

Clinical trials.gov NCT01351909

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT3-01-17.

Abstract P3-15-06: No Correlation between Endocrine Symptoms and Musculoskeletal Symptoms in Women Receiving Adjuvant Aromatase Inhibitor Therapy

Background:

The etiology of Aromatase Inhibitor (AI) associated musculoskeletal symptoms remains unclear. It has been proposed that musculoskeletal side effects are related to the estrogen depletion achieved on AI therapy. Estrogen depletion with AI therapy is known to result in endocrine side effects. The 18-item Functional Assessment of Cancer Therapy Breast Cancer-Endocrine Subscale (FACTB-ES) is a reliable and well validated quality of life questionnaire shown to be sensitive to changes in endocrine symptoms in breast cancer patients. The objective of this study was to determine whether among women with breast cancer treated with adjuvant AI therapy, self reported musculoskeletal side effects correlate with increased hormonal side effects as measured by the FACTB-ES. Methods:

In this 6 month, single center, prospective cohort study, post-menopausal women with hormone-sensitive, non-metastatic breast cancer prescribed AIs by their treating oncologist were evaluated by a rheumatologist at baseline (before starting the AI) and at 6 months. Women who reported new or worsening musculoskeletal symptoms since starting the AI were classified as symptomatic. The FACTB-ES was administered at each visit.

Changes in scores between baseline and 6 months were compared between

the symptomatic and asymptomatic groups

Results:

Thirty-five subjects completed the 6 month follow up period. Nineteen (54%) were symptomatic and n=2 (5.7%) discontinued the AI due to these musculoskeletal symptoms. Mean time to onset of symptoms was 6 weeks (range 2 to 18 weeks). Baseline characteristics including age, ethnicity and body mass index did not differ between the groups. There was no significant difference in hormonal symptoms between groups. Both groups had equivalent worsening of their endocrine symptoms as seen by the reduction in their FACTB-score. The mean change in FACTB-ES score was -2.52 (range: -31.00, 23.00) in the symptomatic women versus -2.06 (range: -19.00, 22.21) in the asymptomatic women (Wilcoxon rank sum p=0.95). Conclusions:

These data suggest that endocrine symptoms as measured by the FACTB-ES do not correlate with the development of musculoskeletal pain in women treated with adjuvant AI therapy for breast cancer. Though larger studies are necessary to confirm these results, the musculoskeletal symptoms associated with AI use may not be estrogen-dependent.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-15-06.

Abstract P2-16-14: The Effect of Tetrathiomolybdate (TM) on Circulating Endothelial Progenitor Cells in Women at Moderate to High Risk of BC Recurrence

Background: Bone marrow (BM) derived endothelial progenitor cells (EPCs) are critical to tumor angiogenesis, are increased in BC patients (pts) and are probably an early marker for paclitaxel response. Copper is required for angiogenesis, and pre-clinical data suggest that TM, a copperdepleting compound, inhibits angiogenesis and maintains tumor dormancy through unknown mechanisms. We sought to measure the effect of TM on BM derived EPCs in pts at high risk of BC recurrence and to evaluate the effect of copper depletion on their absolute number. Methods: This analysis is part of an ongoing phase II study of TM in BC pts at high risk of recurrence defined as any node positive triple negative (TN) BC, Stage III or IV with no evidence of disease (NED). All therapy other than hormonal was completed at least 6 weeks prior to study. Treatment: TM 180 mg daily to achieve a target ceruloplasmin (Cp) level of 5-15 mg/dL (copper depletion), and then 100 mg daily. We monitored levels of EPCs (CD45dim, CD133+, VEGFR2+), CEA, CA15-3, and Cp at baseline and monthly. Imaging studies are done every 6 months (mos). Initial study duration is 24 mos. Extension study for an additional 24 mos in selected pts. Results: 40 pts are enrolled and 566 cycles of TM have been administered. Adjuvant: 28 pts, Stage 4 NED: 12 pts, Triple negative: 11 pts (4 stage 4 NED, 7 Adjuvant). Median age is 51 yrs (range: 29-64). Median number of positive lymph nodes among Stage 2/3 pts is 7 (4-42). Median baseline Cp level is 29 mg/dL (21-47). Among 36 pts who have reached target Cp, the median time to target is 4 wks (2-20 wks). Four pts discontinued treatment before reaching target. The median baseline EPCs is 0.01 cells/ml (0.0-0.286), and the majority of pts’ EPCs were maintained below baseline when Cp levels remained below target (i.e. copper depleted). Toxicity: Grade 3/4 neutropenia occurred in 15 cycles (2.6%) with 1 pt with febrile neutropenia. One cycle was complicated by Grade 3 anemia. All resolved 5-13 days later with TM held and resumed at a lower dose. No other grade 3/4 toxicity was observed. Six pts were diagnosed with recurrent breast cancer at 1, 2, 2, 9, 10 and 10 mos. An EPC rise preceded an abnormal marker or overt relapse by 3-5 months in 4 of 6 pts (2 pts too early to tell). Conclusions: TM is well tolerated in breast cancer patients. TM might contribute to maintaining EPCs below baseline in pts who are copper depleted. We postulate that the increased EPCs noted in 4 pts with recurrent disease 2-4 months prior to overt relapse could represent the turning on of an angiogenic switch, resulting in an outpouring of BM derived EPCs to the new site of metastasis. Other studies geared toward understanding the mechanism for metastases are underway. The trial continues to accrue.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-16-14.

Phase I trial of ixabepilone plus pegylated liposomal doxorubicin in patients with adenocarcinoma of breast or ovary

BACKGROUND

Ixabepilone is a semisynthetic epothilone B analogue that is active in taxane-resistant cell lines and has shown activity in patients with refractory breast and ovarian cancer. We carried out a phase I trial of ixabepilone plus pegylated liposomal doxorubicin (PLD) in patients with advanced taxane-pretreated ovarian and breast cancer.

METHODS

Patients with recurrent ovarian or breast carcinoma received PLD every 3 or 4 weeks plus five different dose schemas of ixabepilone in cohorts of three to six patients.

RESULTS

Thirty patients received a total of 142 treatment cycles of the PLD-ixabepilone combination. The recommended phase II dose and schedule of ixabepilone was 16 mg/m(2) on days 1, 8, and 15 plus PLD 30 mg/m(2) given on day 1, repeated every 4 weeks. Hand-foot syndrome and mucositis were dose limiting when both ixabepilone and PLD were given every 3 or 4 weeks. Objective responses were observed in 3 of 13 patients (23%) with breast cancer and 5 of 17 patients (29%) with ovarian cancer.

CONCLUSION

Ixabepilone may be safely combined with PLD, but tolerability is highly dependent upon the scheduling of both agents. This combination demonstrated efficacy in patients with breast and ovarian cancer and merits further evaluation in these settings.

A Phase II Trial Tetrathiomolybdate (TM), a Copper Depleting Compound, and Its Effect on Circulating Endothelial Progenitor Cells (EPCs) in Patients with Breast Cancer (BC) at High Risk of Recurrence

Background: EPCs are critical to tumor angiogenesis, are increased in BC patients (pts) and are probably an early marker for paclitaxel response. Copper is required for angiogenesis, and pre-clinical data suggest that TM, a copper-depleting compound, inhibits angiogenesis and maintains tumor dormancy. We sought to measure the effect of TM on circulating endothelial progenitor cells (EPCs) in pts at high risk of BC recurrence and to evaluate the effect of copper depletion on EPCs. Methods: This analysis is part of an ongoing phase II study of TM in BC pts at high risk of recurrence defined as any node positive triple negative (TN) BC, Stage III or IV with no evidence of disease (NED). All therapy other than hormonal was completed at least 6 weeks prior to study. Treatment: TM 180 mg daily to achieve a target ceruloplasmin (Cp) level of 5-15 mg/dL (copper depletion), and then 100 mg daily. We monitored levels of EPCs (CD45dim, CD133+, VEGFR2+), CEA, CA15-3, and Cp at baseline and monthly. Imaging studies are done every 6 months (mos). Results: 28 pts are enrolled and 304 cycles of TM have been administered. Adjuvant: 20 pts, Stage 4 NED: 8 pts, Triple negative: 8 pts (5 stage IV NED, 3 Adjuvant) The median age is 51 years (range: 29-64), median number of positive lymph nodes among Stage III patients is 7 (4-42). The median baseline Cp level was 28 mg/dL (21-43). Among 21 patients who have reached target Cp, the median time to target is 6 weeks (2-16 weeks). Two pts discontinued treatment before reaching target. The median baseline EPCs is 17.38 cells/ml (0.0-286.1) Although there was a trend toward increased EPCs at month 1, this was not statistically significant (p=0.8964) and the majority of pts EPCs were maintained below baseline over time when Cp levels were below target (ie. copper depleted). Toxicity: Grade 3/4 neutropenia occurred in 3 patients (0.02%) with 1 pt with febrile neutropenia. All resolved 5-13 days later with TM held and resumed at a lower dose in 2 patients. No other grade 3/4 toxicity was observed. Three patients were diagnosed with recurrent breast cancer at 1, 9 and 10 mos. An EPC rise preceded an abnormal marker or overt relapse by 3-5 months in 2 of 3 pts. Conclusions: TM is well tolerated in breast cancer patients. TM might contribute to maintaining EPCs below baseline in pts who are copper depleted. We postulate that the increased EPCs noted in both patients with recurrent disease 2-4 months prior to overt relapse could represent the turning on of an angiogenic switch, resulting in an outpouring of CEPCs to the new site of metastasis. Other studies geared toward understanding the mechanism for metastases are underway. The trial continues to accrue.Supported by the Susan B Komen for the Cure, NY Community Trust, Breast Cancer Alliance of Greenwich and the Madeline and Stephen Anbinder Foundation.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6090.

Dasatinib Plus Capecitabine for Advanced Breast Cancer: Safety and Efficacy Data from Phase 1 Study CA180-004

Background: SRC is a potential therapeutic target in breast cancer and has a central role in hormone therapy resistance and in osteoclast activity. Dasatinib is a potent SRC inhibitor that inhibits breast cancer cell proliferation and migration in vitro, including synergy with 5FU in some cell lines, and inhibits osteoclast activity in clinical trials. CA180-004 is a phase 1 study designed to identify dose-limiting toxicities (DLT) and recommended phase 2 doses of dasatinib plus capecitabine in women with advanced breast cancer (ABC). Safety and efficacy data are now reported with additional follow-up.Methods: Cohorts of pts with ABC were treated at four dose levels (DL) with capecitabine (mg/m2 twice daily [BID] on D1-14 of 21-day cycles) and dasatinib (mg daily): DL1: capecitabine 825 + dasatinib 50 BID; DL2: capecitabine 825 + dasatinib 70 BID; DL3: capecitabine 1000 + dasatinib 70 BID; DL3a: capecitabine 1000 + dasatinib 100 once daily (QD). All pts had performance status 0-1, prior taxane and/or anthracycline and ≤2 prior chemotherapy-containing regimens for advanced disease. Disease assessments were performed every 6 weeks. DL3a was expanded for further safety and efficacy estimate using best objective response and progression-free survival (PFS) rates.Results: To date, 47 pts with ABC have been treated, 31 in escalation phase plus 16 in expansion (5 too early). Median age was 52 years (range 35-77). Tumor subtypes: 14% were Her2-amplified, 57% ER+ or PR+, 29% triple-negative. Safety was previously reported (ASCO 2009) for escalation phase; no MTD was defined based on DLTs. Of 20 evaluable pts in DL3a, 2 DLTs have been observed: 1 pneumonia, pain and pleural effusion plus 1 diarrhea, neutropenia, vomiting, mucositis and anemia. The most common drug-related adverse events (AEs, any grade) were headache, fatigue/asthenia, nausea/vomiting, diarrhea, hand-foot syndrome (HFS) and pleural effusion. The most common grade 3/4 AEs were fatigue/asthenia, HFS, vomiting and diarrhea. To date, 19 have remained on treatment ≥4 months, including 3 for >1 year. Median duration of treatment (n=42) was 13 weeks; 23 pts have discontinued for progression and 7 for toxicity. Of 38 pts with on-study assessment, 6 had confirmed partial response (treatment durations 17+, 23, 25, 36+, 71, 73 wks), 6 had unconfirmed partial or clinical response (5, 11, 13, 18, 23+, 24 wks), and 9 had prolonged stable disease (16+, 17, 23+, 24+, 25+, 29, 39+, 48+, 63+ wks). Updated efficacy data, including PFS by hormone receptor status, will be presented.Conclusions: Dasatinib and capecitabine combination treatment was well tolerated and encouraging efficacy was observed. Further assessment of this combination is warranted.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3092.

Differences in Breast Cancer Subtypes among Asian-American Women with Invasive Breast Cancer in New York City

Background: Specific breast cancer (BC) subtypes conferring distinct phenotypic and prognostic outcomes have been defined by molecular gene expression arrays. A recent study suggested that differences in BC subtypes exist among ethnic subgroups of Asian women in California. It has also been reported that there are differences in clinical outcomes among Asians with BC in the US, with Filipinos having a worse prognosis compared with other Asians. We sought to determine whether differences in BC subtypes exist among Asians in New York.Methods: Using outpatient registration records from Weill Cornell Breast Center and St. Vincent's Medical Center in New York City, we identified patients who were diagnosed with stage I, II, or III invasive BC between 1997 and 2007 who were of Chinese, Filipino, Japanese or Korean ethnicity. We reviewed pathology records according to an IRB approved protocol and recorded patient data for age, stage, grade, estrogen receptor (ER), progesterone receptor (PR) status, and HER-2/neu at diagnosis. Immunohistochemical surrogates for the four molecularly defined breast cancer subtypes were used according to accepted definitions (Luminal A: ER+Her2-; Luminal B: ER+ Her2+; Her2/neu: Her2+ ER-; Basal-like: ER-PR-, Her2-) Using chi-square analysis, we explored the relationship between ethnicity and BC subtypes.Results: 346 Asian women were identified with invasive breast cancer. Among the Chinese subgroup, 67% were of the Luminal A subtype, 15.3% were Luminal B, 10% were the Her2/neu subtype and 8.5% were Basal-like. Filipinos had a higher proportion of Luminal B cancers compared to the other ethnic groups. Filipinos and Koreans had a higher proportion of the Her2+/ER- subtype compared to Chinese and Japanese (P=0.004 by chi-square test). When considering all Her2/neu positive cancers, Filipinos had a significantly higher proportion of HER-2/neu positivity (46%) compared to Chinese (25%), Japanese (14%) and Korean (29%) groups (P=0.002). Filipinos and Koreans had a higher proportion of ER negative cancers and Grade III cancers compared to Chinese and Japanese (P=0.001 for ER status and P=0.01 for grade). In our series, Korean subjects were significantly younger than the other three ethnic groups (P<0.0001 by AVOVA test).Conclusions: Differences in BC subtypes exist among Asian women with invasive breast cancer in New York. Filipino women are significantly more likely to have HER-2/neu positive BC compared with Chinese, Japanese, and Korean women. Our results are supportive of results from a study in which differences in distribution of Her2/neu positive cancers among Asians in California were seen. Furthermore, these findings provide one explanation for the worse clinical outcome for Filipinos compared with other Asians that has been previously reported.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3067.

A phase I/II study of CR011-vcMMAE, an antibody-drug conjugate, in patients (pts) with locally advanced or metastatic breast cancer (MBC)

1067

Background: Glycoprotein NMB (GPNMB), also known as osteoactivin, has been shown to regulate metastasis of breast cancer in vivo. CR011-vcMMAE, a fully-human monoclonal anti-GPNMB antibody conjugated to the tubulin inhibitor monomethylauristatin E, is safe and active in pts with advanced melanoma. This is the first study of CR011-vcMMAE in breast cancer. Methods: Eligible pts with MBC had ≥ 2 prior chemotherapy regimens, including a taxane, an anthracycline, and capecitabine; and ECOG PS ≤ 2. Doses were escalated to 1.88 mg/kg IV q3w (the maximum tolerated dose [MTD] in melanoma) using a standard 3+3 design. Immunohistochemistry (IHC) with goat polyclonal antibody to GPNMB was performed on pt biopsy specimens and on tissue microarrays containing normal breast, DCIS, breast tumor and lymph node metastases. Results: 10 pts with MBC (median age 57, range 36 - 69) had a median of 7 prior regimens and were treated with CR011-vcMMAE for a median of 2 cycles (range 1–4). In the first 2 pts at 1.34 mg/kg, dose limiting toxicity of worsening peripheral sensory neuropathy was observed. Pts with baseline neuropathy worse than grade 1 were subsequently excluded. Pts were treated at 1.0 mg/kg (n = 3), 1.34 mg/kg (n = 5), and 1.88 mg/kg (n = 2); enrollment at 1.88 mg/kg is continuing. Other adverse events (AEs) were grade 1/2 anorexia and pain in 4 pts; diarrhea, rash, fatigue, and neuropathy in 3 pts; and grade 3 rash in 1 pt. Evidence of antitumor activity has been observed. A response of 37% tumor shrinkage was seen in a pt after only 2 cycles and is ongoing. A second pt had a 51% reduction after 2 cycles, but had PD after 12 weeks. Breast tumor samples were more likely to stain positive for GPNMB than normal breast tissues. Conclusions: CR011-vcMMAE 1.34 mg/kg IV q3w is well-tolerated in heavily pretreated pts with MBC. The 1.88 mg/kg q3w dose is being assessed and phase II expansion is planned at the MTD. IHC of pt tumor specimens is being evaluated.

[Table: see text]

Kinetics of amoxicillin and clavulanate degradation alone and in combination in aqueous solution under frozen conditions

Kinetics of the reactions of amoxicillin sodium and potassium clavulanate alone and in combination were investigated in the frozen state at selected pH values of 2.0, 4.6 and 7.0. Extrapolation of the rate constant values to the frozen state from the liquid state data indicated marked acceleration of the rates of amoxicillin and clavulanate degradation for the pH values investigated. The highest acceleration in rate recorded was 15.0-fold for clavulanate and the lowest value was 4.6-fold for amoxicillin at -7.3 degrees C in the hydrochloric acid system. The rate constant values obtained were interpreted in terms of the concentration model [Pincock, R.E., Kiovsky, T.E., 1966. Kinetics of reactions in frozen solution. J. Chem. Educ. 43, 358-360], phase-temperature relationship of the solutes, buffer catalysis, pH change and polymerization reactions. A kinetic model was deduced for the hydrochloric acid system providing adequate explanation of the experimental results. A large stabilizing effect of sodium chloride used for maintaining constant ionic strength (micro=0.5) was evident in this system. The shelf-life of amoxicillin was increased from 2.2 to 58.7h at -7.3 degrees C when sodium chloride was included in the hydrochloric acid system.

Phase II study of eribulin mesylate (E7389) halichondrin b analog in patients with refractory breast cancer

1034

Background: Eribulin is a structurally simplified analog of halichondrin B, which inhibits microtubule dynamics via a novel mechanism characterized by suppression of microtubule growth, lack of effect on microtubule depolymerization, and sequestration of tubulin into nonfunctional aggregates. This study was designed to assess the activity and tolerance of eribulin in chemotherapy refractory patients with advanced breast cancer. Methods: Eribulin was evaluated in a single-arm Phase II trial in female patients with refractory breast cancer, ECOG performance status of 0–1, measurable disease, and neuropathy ≤ Grade 2. Patients received ≥ 1 prior chemotherapy regimen, including an anthracycline and a taxane. Eribulin was administered as a 2–5 min IV bolus of 1.4 mg/m2 on Days 1, 8, and 15 of a 28-Day cycle (Group 1). The schedule was modified to Days 1 and 8 of a 21-Day cycle (Group 2), because of dose delays. The primary efficacy endpoint was ORR according to RECIST criteria based upon independent review (IR) of tumor assessment. Results: Of 104 patients enrolled, 103 received eribulin treatment: 70 in Group 1, 33 in Group 2. Median age was 55 yrs (range 32–84). Patients had received a median of 4 prior chemotherapy regimens (range 1–11). Sixty-one percent of tumors were ER+, 14% Her2/neu 3+, and 29% were triple (ER, PR, Her-2) negative. The incidence of dose interruption, delay, or omission during Cycle 1 was 63% (Group 1) and 18% (Group 2). The most common drug related toxicities were neutropenia (75%, Grades 3: 31%, Grade 4: 30%, febrile neutropenia: 3.9%), fatigue (52%, Grade 3: 2.9%, no Grade 4), alopecia (Grade 1/2: 41%), nausea (37%, Grade 3: 1%, no Grade 4), and anemia (36%, Grade 3: 1%, no Grade 4). Peripheral neuropathy occurred in 34% of patients (Grade 3: 3.9%, no Grade 4). Best overall response rate (all PR) by IR was 14.5% and 15.2% in Groups 1 and 2, respectively; the combined ORR was 14.7% (95 % CI: 9–23%). Median PFS was 85 days, and the 6 mo PFS rate was 31%. Conclusions: Eribulin given as a 2–5 min IV infusion on Days 1, 8 of a 21-Day cycle or Days 1, 8, 15 of a 28-Day cycle exhibited a 15% PR rate by IR and a low incidence of Grade 3 neuropathy in this heavily chemotherapy pretreated population. The most common toxicity was neutropenia. The 21-Day schedule had an acceptable toxicity profile.

No significant financial relationships to disclose.

Phase I clinical trial of ixabepilone and pegylated liposomal doxorubicin in patients with advanced breast or ovarian cancers: New York Cancer Consortium Trial P7229

2570

Background: Ixabepilone (IX) is a semisynthetic epothilone B analog with activity in patients (pts) with taxane refractory cancer. Two phase III clinical trials in breast cancer (BC) and a phase II study in ovarian cancer (OC) have recently been completed. Pegylated liposomal doxorubicin (PLD) is used for the treatment of platinum refractory OC and has activity in patients with metastatic BC. Methods: We have completed enrollment of a phase I study of PLD IV and ixabepilone IV over 3 hours. 18 pts with metastatic cancer (10 BC and 8 OC) with median age 51 were enrolled from 1/13/06 to 12/22/06. A total of 60 cycles has been administered to date. 3 OC patients enrolled at dose level 3 have not yet completed 2 cycles of treatment and are not yet evaluable. Results: Dose limiting toxicities (DLT) based on toxicities experienced during the first 2 cycles is provided in the table below. Adverse events (AE) occurring in any cycle were: Grade 4 AE: neutropenia < 7 days (1 pt). Grade 3 AE: palmar plantar erythrodysesthesia (PPE) (4), mucositis (3), infection (2), fatigue (2), neutropenia (2), thrombocytopenia (2), anemia (1), neuropathy (1), bilirubin (1). Non-hematological grade 2 AEs included: mucositis (4), PPE (3), infection (2), neuropathy (2), rash (3), pain (3), fever (1), myalgias (1), and anorexia (1). Responses so far for 10 BC pts are PR (1) SD (3) PD (6) and for 5 OC pts are PR (1) SD (2) PD (2). Updated results will be presented. Conclusions: Although the recommended phase II dose when given every 3 weeks is 30 mg/m2 for PLD and 32 mg/m2 for IX by our criteria, PPE and mucositis became problematic when treatment was continued beyond 2 cycles. We are therefore exploring a 4 week PLD schedule, evaluating IX given either every 4 weeks (as shown) or weekly (on days 1, 8, and 15). A phase II trial of the combination in platinum refractory OC will be initiated upon completion of the phase I. Supported by N01-CM-62204

[Table: see text]

[Table: see text]

Circulating endothelial progenitor cells correlate to stage in patients with invasive breast cancer

616

Background: Tumor growth and metastasis is dependent on neo-angiogenesis. Both pre-existing and circulating vascular cells have been shown to contribute to the assembly of tumor neo-vessels in specific tumors. Mobilization of endothelial progenitor cells (EPCs) from the bone marrow constitutes a crucial step in the formation of de novo blood vessels, and levels of peripheral blood EPCs have been shown to be increased in certain malignant states. However, the role of circulating EPCs in breast cancer is largely unknown. Methods: We recruited twenty-five patients with biopsy-proven invasive breast cancer (BC) at Weill Cornell Breast Center to participate in a pilot study investigating the correlation of circulating EPCs to extent of disease and initiation of chemotherapy. For each patient, a baseline sample was drawn before systemic treatment, and for seventeen of those patients, a second sample was taken after the first round of chemotherapy. Levels of peripheral blood EPCs, as defined by co-expression of CD133 and VEGFR2, were quantified by flow cytometry. Results: BC patients with stage III & IV disease had statistically higher levels of circulating EPCs than did patients with stage I & II disease (median=165,000 EPCs/5×106MNCs vs. median=6,920 EPCs/5x106MNCs, respectively, p < 0.0001 by Wilcoxon rank-sum test). In addition, in late-stage patients, levels of EPCs demonstrated a statistically significant drop after initiation of chemotherapy (median=162,500 EPCs/5x106MNCs [pre] vs. median=117,500 EPCs/5x106MNCs [post], p = 0.01 by Wilcoxon signed-rank test). Conclusion: These results suggest that circulating EPCs may serve as a potential tumor biomarker in breast cancer and that EPCs may represent a plausible target for future therapeutic intervention. Supported in part by the Mentored Medical Student in Clinical Research Program (General Clinical Research Center/National Institutes of Health Grant M01RR00047), Madeline & Stephen Anbinder Clinical Scholar Award, and Anne Moore Breast Cancer Research Fund

No significant financial relationships to disclose.

Phase II trial of ixabepilone in patients with metastatic breast cancer (MBC) who are resistant to an anthracycline, a taxane and capecitabine

660

Background: Patients (pts) with MBC previously treated with an anthracycline, a taxane and capecitabine have very limited treatment options. Ixabepilone is the first semi-synthetic analog in a new class of cytotoxic agents, the epothilones. It has shown activity in breast and other tumors. Methods: This single-arm Phase II trial was designed to assess the objective response rate (ORR) of ixabepilone in MBC pts resistant to an anthracycline, a taxane and capecitabine. Pts had to be resistant to each regimen as defined by progression within 8 wks in the metastatic setting or recurrence within 6 months (mo) of adjuvant anthracycline/taxane. Capecitabine must have been given in the metastatic setting. Response was assessed by an independent radiology review committee (IRRC; primary analysis) and by each investigator per RECIST. Ixabepilone was administered IV at 40 mg/m2 over 3 h every 3 wks. Results: A total of 126 pts were treated: median age 51 yrs (range 30–78), Karnofsky PS range 70–100% and 70% pts had baseline liver metastases. 88% pts had received ≥2 prior metastatic regimens. 113 pts were response evaluable (had target disease by IRRC and met eligibility criteria for prior therapy). Median duration of response was 5.3 mo. Stable disease (SD) was the best response in 50% pts and 14% pts had SD ≥6 mo duration. Median PFS was 3.1 mo. Pts received a median of 4 cycles (range 1–16). The most common Grade 3/4 treatment-related adverse events were sensory peripheral neuropathy (14%), fatigue (10%), myalgia (7%), and stomatitis (6%). The neuropathy was cumulative and reversible. Time to resolution (to Grade 1 or baseline) for Grade 3/4 neuropathy was 5.4 wks by Kaplan-Meier analysis. Grade 3/4 neutropenia and thrombocytopenia occurred in 54% and 7% of pts, respectively. Febrile neutropenia was reported in 3% pts. Conclusions: Ixabepilone demonstrates promising clinical activity and a manageable safety profile in patients highly resistant to standard chemotherapy.

[Table: see text]

[Table: see text]

E7389, a novel anti-tubulin, in patients with refractory breast cancer

653

Background: E7389 is a synthetic analog of halichondrin B, with a broad anti- proliferative activity against tumor cells. Methods: E7389 was evaluated in an open-label, single-arm Phase II trial as monotherapy for patients with refractory breast cancer (≥2 prior chemotherapy regimens, which must have included an anthracycline and a taxane). E7389 was administered as an IV bolus of 1.4 mg/m2 on Days 1, 8, and 15 of a 28-day cycle (group 1), or on Days 1 and 8 of a 21-day cycle (group 2). The primary efficacy endpoint was ORR. Results: As of 9 December 2005, 88 patients had received treatment, 68 in group 1 and 20 in group 2. Median age was 55 yrs (range 36–84) and ECOG performance status 0–1. Sixty-six percent of the tumors were ductal carcinomas, 6% lobular, and 27% were unclassified. Sixty percent of the tumors were ER+, 47% PR+, and 17% Her2/neu 3+. The patients had received at least two previous regimens, with a median number of 5 (range 2–14). Forty-eight percent of the patients had also used hormonal therapy. Forty-nine patients in group 1 and 12 patients in group 2 had completed their 2nd cycle of treatment, and twenty-one in group1 and 1 in group 2 their 4th cycle. Safety: The major toxicity related to study drug was neutropenia. Among 73 patients with preliminary safety data available, two patients had Grade 3 febrile neutropenia, and 31 had Grade 3 or 4 neutropenia or leukopenia. The other Grade 3 toxicities encountered in more than two patients were dehydration (4 patients) and dyspnea (4 patients). Grade 3 peripheral neuropathy was reported in 2 patients. Efficacy: At the end of cycle four there were 10 (15.2%) confirmed partial responses (PRs) out of 66 evaluable patients in group 1, and 1 confirmed PR (5.6%) out of 18 evaluable patients in group 2. The median duration of confirmed responses was 113 days. Conclusions: Based on the safety and efficacy in this refractory breast cancer population, E7389 appears to be a therapy worthy of continued investigation in patients with heavily pretreated breast cancer. In order to comply with the current demand for individualized cancer care, bio-markers which would predict the sensitivity to E7389 are being searched in the tumor samples of the patients in the current and forthcoming studies.

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Therapy-related myelodysplastic syndrome after autologous stem cell transplantation for breast cancer

Therapy-related myelodysplastic syndrome and acute myelogenous leukemia (t-MDS/AML) are serious complications of chemotherapy and radiotherapy for cancer. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) may be associated with an increased incidence of these complications. The frequency of t-MDS/AML after ASCT for breast cancer is uncertain. We reviewed our database of 379 consecutive breast cancer ASCT patients treated with alkylator-based chemotherapy, followed for a median of 1.52 years (range 0-8.97), with a median survival of 6.16 years. Three patients have developed tMDS/AML. The probability of developing this complication at 5 years is 0.032 in our series. We have used pathologic, cytogenetic and molecular methods to evaluate which portions of therapy may have predisposed to the development of this complication. Cytogenetic abnormalities were not found in the stem cell harvests of these patients by metaphase analysis or by fluorescence in situ hybridization (FISH). One patient demonstrated a clonal X chromosome inactivation pattern in her stem cell harvest, indicating pre-transplant chemotherapy may have been responsible for the development of her leukemia. As two of our patients developed this complication at greater than 4 years post-transplant, the number of cases may increase with longer follow-up. While the incidence appears to be low, further prospective and retrospective analysis will be necessary to determine which portions of therapy predispose to the development of t-MDS/AML in patients undergoing ASCT for treatment of breast cancer.

Randomized Trial of Black Cohosh for the Treatment of Hot Flashes Among Women With a History of Breast Cancer

PURPOSE: Most breast cancer survivors experience hot flashes; many use complementary or alternative remedies for these symptoms. We undertook a randomized clinical trial of black cohosh, a widely used herbal remedy for menopausal symptoms, among breast cancer patients.

PATIENTS AND METHODS: Patients diagnosed with breast cancer who had completed their primary treatment were randomly assigned to black cohosh or placebo, stratified on tamoxifen use. At enrollment, patients completed a questionnaire about demographic factors and menopausal symptoms. Before starting to take the pills and at 30 and 60 days, they completed a 4-day hot flash diary. At the final visit, they completed another menopausal symptom questionnaire. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured in a subset of patients at the first and final visits.

RESULTS: Of 85 patients (59 on tamoxifen, 26 not on tamoxifen) enrolled in the study, 42 were assigned to treatment and 43 were assigned to placebo; 69 completed all three hot flash diaries. Both treatment and placebo groups reported declines in number and intensity of hot flashes; the differences between the groups were not statistically significant. Both groups also reported improvements in menopausal symptoms that were, for the most part, not significantly different. Changes in blood levels of FSH and LH also did not differ in the two groups.

CONCLUSION: Black cohosh was not significantly more efficacious than placebo against most menopausal symptoms, including number and intensity of hot flashes. Our study illustrates the feasibility and value of standard clinical trial methodology in assessing the efficacy and safety of herbal agents.

Reduction of paclitaxel-induced peripheral neuropathy with glutamine

PURPOSE

Dose-limiting toxicity of many newer chemotherapeutic agents is peripheral neuropathy. Prior attempts to reduce this side effect have been unsuccessful. We report on the possible successful reduction of peripheral neuropathy with glutamine administration after high-dose paclitaxel.

EXPERIMENTAL DESIGN

Patients entered a high-dose chemotherapy protocol in which the first high-dose cycle was paclitaxel at 825 mg/m(2) given over 24 h. The first cohort of patients did not receive glutamine, and the second cohort of patients received glutamine at 10 g orally three times a day for 4 days starting 24 h after completion of paclitaxel. Neurological assessment was performed at baseline, and at least 2 weeks after paclitaxel, and consisted of a complete neurological exam and nerve conduction studies.

RESULTS

There were paired pre- and post-paclitaxel evaluations on 33 patients who did not receive glutamine and 12 patients who did. The median interval between pre- and post-exams was 32 days. For patients who received glutamine, there was a statistically significant reduction in the severity of peripheral neuropathy as measured by development of moderate to severe dysesthesias and numbness in the fingers and toes (P < 0.05). The degree and incidence of motor weakness was reduced (56 versus 25%; P = 0.04) as well as deterioration in gait (85 versus 45%; P = 0.016) and interference with activities of daily living (85 versus 27%; P = 0.001). Moderate to severe paresthesias in the fingers and toes were also reduced (55 versus 42% and 64 versus 50%, respectively), although this value was not statistically significant. All of these toxicities were reversible over time.

CONCLUSIONS

Glutamine may reduce the severity of peripheral neuropathy associated with high-dose paclitaxel; however, results from randomized, placebo-controlled clinical trials will be needed to fully assess its impact, if any. Trials are currently ongoing to assess its efficacy for standard-dose paclitaxel in breast cancer and other tumors for which peripheral neuropathy is the dose-limiting toxicity.

Phase I trial of retroviral-mediated transfer of the human MDR1 gene as marrow chemoprotection in patients undergoing high-dose chemotherapy and autologous stem-cell transplantation

PURPOSE

Normal bone marrow cells have little or no expression of the MDR p-glycoprotein product and, therefore, are particularly susceptible to killing by MDR-sensitive drugs, such as vinca alkaloids, anthracyclines, podophyllins, and paclitaxel and its congeners. Here we report the results of a phase I clinical trial that tested the safety and efficacy of transfer of the human multiple drug resistance (MDR1, MDR) gene into hematopoietic stem cells and progenitors in bone marrow as a means of providing resistance of these cells to the toxic effects of cancer chemotherapy.

PATIENTS AND METHODS

Up to one third of the harvested cells of patients who were undergoing autologous bone marrow transplantation as part of a high-dose chemotherapy treatment for advanced cancer were transduced with an MDR cDNA-containing retrovirus; these transduced cells were reinfused together with unmanipulated cells after chemotherapy.

RESULTS

High-level MDR transduction of erythroid burst-forming unit (BFU-E) and colony-forming unit-granulocyte macrophage (CFU-GM) derived from transduced CD34+ cells was shown posttransduction and prereinfusion. However, only two of the five patients showed evidence of MDR transduction of their marrow at a low level at 10 weeks and 3 weeks, respectively, posttransplantation. The cytokine-stimulated transduced cells may be out-competed in repopulation by unmanipulated normal cells that are reinfused concomitantly. The MDR retroviral supernatant that was used was shown to be free of replication-competent retrovirus (RCR) before use, and all tests of patients' samples posttransplantation were negative for RCR. In addition, no adverse events with respect to marrow engraftment or other problems related to marrow transplantation were encountered.

CONCLUSION

These results indicate the feasibility and safety of bone marrow gene therapy with a potentially therapeutic gene, the MDR gene.

High-dose chemotherapy with autologous stem cell support for breast cancer

High-dose chemotherapy is increasingly utilized for the treatment of metastatic and high-risk breast cancer. Autologous Blood and Marrow Transplant Registry data reveal that a single high-dose cycle of chemotherapy with stem cell support can produce high complete response rates, with 10% to 20% of patients disease-free at 5 years. For patients with locally advanced disease, pooled results estimate 63% without relapse at 3 years for stage II and III disease and 42% for inflammatory breast cancer. New strategies to improve on these results include the incorporation of newly identified active drugs into established regimens and the use of multiple high-dose cycles. Multicycle chemotherapy produces complete response rates ranging from 35% to 93% depending on the regimen. Additional strategies include the use of monoclonal antibodies, immunotherapy, and gene therapy for post-transplant consolidation. The strongest predictor of long-term disease-free survival in virtually all studies is a complete response prior to or following high-dose chemotherapy. Randomized studies are now in the process of being completed in Europe and the United States with reporting scheduled over the next several years.

Rapidly cycled courses of high-dose alkylating agents supported by filgrastim and peripheral blood progenitor cells in patients with metastatic breast cancer

Our purpose was to determine the feasibility of a regimen of multiple, rapidly cycled courses of high-dose alkylating agents, including paired courses of escalating doses of thiotepa, supported by peripheral blood progenitor cells and filgrastim, in patients with responding stage IV breast cancer. The regimen consisted of two courses of cyclophosphamide (3.0 g/m2/course) followed by two courses of thiotepa (500-700 mg/m2/course). All courses were supported by filgrastim. Leukaphereses were performed after each cyclophosphamide course to harvest peripheral blood progenitors (PBPs) for use as rescue following thiotepa administration. The planned interval for all courses was 14 days. Forty-two patients were enrolled. Thirty-eight received all four courses, and four did not receive the second thiotepa cycle due to poor PBP mobilization. The maximum dose of thiotepa that was administered was 700 mg/m2 x 2. At this dose, one patient developed encephalopathy, which resolved over several weeks. The median number of days to an absolute neutrophil count of 0.5 x 10(9)/liter after PBP reinfusion for cycles 1 and 2 of thiotepa were 9 (range, 7-16) and 9 (range, 8-13) days, respectively. The corresponding values for platelet recovery to >20 x 10(9)/liter were 11 (range, 8-39) and 12 (range, 10-28) days, respectively. There were no treatment-related deaths. Hospitalization was required following 28 of 84 cyclophosphamide courses and 76 of 80 thiotepa courses. Four patients developed grade III-IV mucositis. The median interval between courses of treatment was 15 (range, 13-29) days. Of 19 patients who entered the protocol with measurable disease in partial response from prior therapy, 8 (42%) achieved complete response following the high-dose therapy. Nine (21%) of 42 remain progression free at a median follow-up of 28 (range, 20-32) months. Therefore, we concluded that the administration of multiple, rapidly cycled courses of high-dose alkylating agents is feasible.

High-dose therapy for breast cancer

The high incidence of breast cancer in young women, and the unfavorable prognosis for those who present with a high number of lymph nodes involved with cancer, has encouraged the development and evaluation of new treatment strategies. The use of dose intensification is supported by laboratory and clinical models. In this review article, the use of dose intensification supported by hemopoietic growth factors, and also by hemopoietic stem cells, is discussed. The results of published studies of high-dose chemotherapy in Stage II, III, and IV breast cancer are discussed and summarized, including those randomized comparisons with more conventional therapy. Improvements in supportive care continue to reduce the risks from neutropenia and thrombocytopenia, and these and other toxicities are likely to decrease as side-effects are anticipated and experience increases.

High-dose chemotherapy of metastatic breast cancer: a review

Very-high-dose chemotherapy produces frequent complete responses in patients with metastatic breast cancer. These responses are transient in patients with disease that had relapsed following, or was refractory to, prior conventionally dosed therapy, but when used as first chemotherapy for metastatic disease or as consolidation for patients with responding cancer, a minority achieve durable complete remissions. Improvements in supportive care, especially in hematopoietic support, have resulted in a considerable reduction in the toxicity of this therapy and may allow further intensification through the use of multiple, rapidly cycled courses.

Early mortality and the retinoic acid syndrome in acute promyelocytic leukemia: impact of leukocytosis, low-dose chemotherapy, PMN/RAR-alpha isoform, and CD13 expression in patients treated with all-trans retinoic acid

All-trans retinoic acid (RA) has proven a major advance in the treatment of acute promyelocytic leukemia (APL). However, the proper management of patients who present with or develop leukocytosis during remission induction with all-trans RA is not established, nor is there a clear relation between leukocytosis and the development of the retinoic acid syndrome. We reviewed the course of our patients who underwent induction with all-trans RA to identify potential factors that might predict for the development of this syndrome and to identify which patients, if any, might specifically benefit from additional treatment with cytotoxic chemotherapy. Seventy-eight courses of all-trans RA therapy were administered to patients with a molecular diagnosis of APL. Initial and peak leukocyte counts, their rate of rise, leukocyte count criteria developed in Europe, and cell surface marker expression were all analyzed relative to subsequent development of both the RA syndrome as well as all causes of early mortality. The outcome of patients who received specific treatment for retinoid-induced leukocytosis was also examined. No factor was found to consistently predict for the development of the RA syndrome. Although the occurrence of the syndrome was positively associated with the peak value of the peripheral blood leukocyte count (P = .001), neither the initial leukocyte count nor the rate of rise in leukocyte counts on days preceding onset of the syndrome were sufficiently well-correlated to be clinically useful (P = .21). The leukocyte count criteria developed in Europe had a sensitivity of 62%, a specificity of 69%, and a positive predictive value that ranged from only 44% to 72%. However, we unexpectedly found that basal expression of CD13 (aminopeptidase N), a cell surface enzyme previously linked to tumor cell invasion and an inferior outcome in patients with acute myeloid leukemia, was highly associated with both development of the syndrome (P < .05) as well as an elevated leukocyte count (P = .006). Neither low-dose chemotherapy nor leukapheresis prevented development of the syndrome nor ameliorated its effects. In fact, 9 of 11 patients who received these interventions sustained fatal or near-fatal events, most of which were due to hemorrhage. However, early treatment with a short-course of high-dose corticosteroids halted progression of the syndrome in most cases. Finally, we found that expression of the type "A" isoform of PML/RAR-alpha (also known as bcr3 or "short") was associated with a significantly shorter duration of relapse-free and overall survival (P = .005).(ABSTRACT TRUNCATED AT 400 WORDS)

Therapeutic and neurotoxic effects of 2-chlorodeoxyadenosine in adults with acute myeloid leukemia

Despite expectations that 2-chlorodeoxyadenosine (2-CdA) would prove active primarily in lymphoproliferative diseases, early reports suggested unexpected high activity of this drug in heavily pretreated children with acute myeloblastic leukemia (AML) at a maximally tolerated dose of 8.9 mg/m2/day for 5 days. In view of these findings, we conducted an escalating dose trial of 2-CdA in adult patients with relapsed or resistant AML. Thirty-six patients who had received extensive prior therapy were treated at 9 dose levels of 2-CdA at daily doses ranging from 5 to 21 mg/m2 for 5 days. 2-CdA eliminated leukemic blasts from the peripheral blood in 32 of 36 cases; however, bone marrow hypoplasia was seen only at daily dose levels > or = 15 mg/m2. We observed a total of 3 complete remissions: 1 at the 15 mg/m2/d dose level and 2 at the 21 mg/m2/d dose level; these responses persisted for 3, 2, and 3 months, respectively. Although prolonged myelosuppression would have been dose-limiting at 21 mg/m2/d for 5 days, the most important adverse effect was the development of a sensorimotor peripheral neuropathy. This reaction, whose onset was substantially delayed after completion of drug treatment, was observed in 2 of 5 patients at the 19 mg/m2/d level and in 4 of 4 evaluable patients at the 21 mg/m2/d level. Pathologically, this process was characterized by axonal degeneration and secondary demyelination. Other side effects included reactivation of a posttransplant Epstein-Barr virus-related lymphoma in 1 patient and tumor lysis syndrome. We conclude that the maximally tolerable dose of 2-CdA in adult patients (17 mg/m2/d for 5 days) in approximately twofold in excess of that previously reported in children and that the limiting toxic effect is a degenerative neuropathic disorder. We confirm that this drug has definite activity in AML, but the magnitude of this effect needs to be determined in larger numbers of patients who have received less extensive therapy. This agent deserves further evaluation in patients with both AML and acute lymphoblastic leukemia at these higher doses and perhaps as part of a preparative regimen for patients undergoing bone marrow transplantation.

High-intensity chemotherapy with peripheral blood progenitor cell support

In a series of clinical studies at Memorial Sloan-Kettering Cancer Center, we have used hematopoietic growth factors and peripheral blood-derived hematopoietic progenitor cells to facilitate delivery of multiple courses of high-dose chemotherapy at abbreviated treatment intervals. In these studies, we have demonstrated the feasibility of cross-over regimens involving induction chemotherapy with high-dose cyclophosphamide, supported by granulocyte colony-stimulating factor and followed by multiple peripheral blood leukapheresis to harvest progenitor cells. These cells are then used as rescue for the consolidation component of treatment, which, in the earlier-generation studies, consisted of a single course of high-dose carboplatin/etoposide/cyclophosphamide chemotherapy. In subsequent studies, patients received either four courses of high-dose carboplatin or carboplatin/cyclophosphamide or tandem courses of thiotepa. In all cases, the planned interval between treatments was 14 days, and the achieved median was approximately 16 days. These studies show that the administration of high-intensity regimens that deliver multiple courses of very high-dose chemotherapy at relatively brief intervals is feasible. Our current research focuses on exploiting these findings to devise disease-specific regimens for breast and ovarian cancer.