Iniparib plus chemotherapy in metastatic triple-negative breast cancer.

BACKGROUND: Triple-negative breast cancers have inherent defects in DNA repair, making this cancer a rational target for therapy based on poly(adenosine diphosphate-ribose) polymerase (PARP) inhibition. METHODS: We conducted an open-label, phase 2 study to compare the efficacy and safety of gemcitabine and carboplatin with or without iniparib, a small molecule with PARP-inhibitory activity, in patients with metastatic triple-negative breast cancer. A total of 123 patients were randomly assigned to receive gemcitabine (1000 mg per square meter of body-surface area) and carboplatin (at a dose equivalent to an area under the concentration-time curve of 2) on days 1 and 8--with or without iniparib (at a dose of 5.6 mg per kilogram of body weight) on days 1, 4, 8, and 11--every 21 days. Primary end points were the rate of clinical benefit (i.e., the rate of objective response [complete or partial response] plus the rate of stable disease for ≥6 months) and safety. Additional end points included the rate of objective response, progression-free survival, and overall survival. RESULTS: The addition of iniparib to gemcitabine and carboplatin improved the rate of clinical benefit from 34% to 56% (P=0.01) and the rate of overall response from 32% to 52% (P=0.02). The addition of iniparib also prolonged the median progression-free survival from 3.6 months to 5.9 months (hazard ratio for progression, 0.59; P=0.01) and the median overall survival from 7.7 months to 12.3 months (hazard ratio for death, 0.57; P=0.01). The most frequent grade 3 or 4 adverse events in either treatment group included neutropenia, thrombocytopenia, anemia, fatigue or asthenia, leukopenia, and increased alanine aminotransferase level. No significant difference was seen between the two groups in the rate of adverse events. CONCLUSIONS: The addition of iniparib to chemotherapy improved the clinical benefit and survival of patients with metastatic triple-negative breast cancer without significantly increased toxic effects. On the basis of these results, a phase 3 trial adequately powered to evaluate overall survival and progression-free survival is being conducted. (Funded by BiPar Sciences [now owned by Sanofi-Aventis]; ClinicalTrials.gov number, NCT00540358.).

Mutation profiling identifies numerous rare drug targets and distinct mutation patterns in different clinical subtypes of breast cancers.

The mutation pattern of breast cancer molecular subtypes is incompletely understood. The purpose of this study was to identify mutations in genes that may be targeted with currently available investigational drugs in the three major breast cancer subtypes (ER+/HER2-, HER2+, and Triple Negative). We extracted DNA from fine needle aspirations of 267 stage I-III breast cancers. These tumor specimens typically consisted of >80% neoplastic cells. We examined 28 genes for 163 known cancer-related nucleic acid variations by Sequenom technology. We observed at least one mutation in 38 alleles corresponding to 15 genes in 108 (40%) samples, including PIK3CA (16.1% of all samples), FBXW7 (8%), BRAF (3.0%), EGFR (2.6%), AKT1 and CTNNB1 (1.9% each), KIT and KRAS (1.5% each), and PDGFR-α (1.1%). We also checked for the polymorphism in PHLPP2 that is known to activate AKT and it was found at 13.5% of the patient samples. PIK3CA mutations were more frequent in estrogen receptor-positive cancers compared to triple negative breast cancer (TNBC) (19 vs. 8%, p=0.001). High frequency of PIK3CA mutations (28%) were also found in HER2+ breast tumors. In TNBC, FBXW7 mutations were significantly more frequent compared to ER+ tumors (13 vs. 5%, p=0.037). We performed validation for all mutated alleles with allele-specific PCR or direct sequencing; alleles analyzed by two different sequencing techniques showed 95-100% concordance for mutation status. In conclusion, different breast cancer subtypes harbor different type of mutations and approximately 40 % of tumors contained individually rare mutations in signaling pathways that can be potentially targeted with drugs. Simultaneous testing of many different mutations in a single needle biopsy is feasible and allows the design of prospective clinical trials that could test the functional importance of these mutations in the future.

Presentation, diagnosis, and management of the Li-Fraumeni syndrome.

Li-Fraumeni syndrome is a hereditary cancer syndrome that results in a dramatically increased risk of developing cancer over a patient's lifetime. Proper understanding of this syndrome is important for physicians across all specialties, as it can result in earlier cancer diagnosis and treatment. Here, we present the case of a patient presenting with Li-Fraumeni syndrome and discuss the appropriate screening recommendations and management of patients with this disorder.

Dose-dense doxorubicin and cyclophosphamide followed by dose-dense albumin-bound paclitaxel plus bevacizumab is safe as adjuvant therapy in patients with early stage breast cancer.

UNLABELLED: Every-2-week (dose-dense) adjuvant doxorubicin (A) plus cyclophosphamide (C) followed by cremophor-formulated paclitaxel (cf-P) was efficacious in metastatic breast cancer (BC). Albumin-bound paclitaxel (ab-P) was safe and more effective than cf-P, and the addition of bevacizumab to cf-P improved efficacy. This study compared the safety of dose-dense ab-P vs cf-P plus bevacizumab following dose-dense adjuvant AC for early-stage BC. PATIENTS AND METHODS: Women with operable, histologically confirmed BC were randomized to 4 cycles of dose-dense A 60 mg/m(2) plus C 600 mg/m(2) IV with SC pegfilgrastim, followed by 4 cycles of either dose-dense IV ab-P 260 mg/m(2) or cf-P 175 mg/m(2). Bevacizumab was given during and following chemotherapy. 97 and 96% of patients completed 4 cycles of AC therapy, while 84 and 85% of patients completed 4 cycles of taxane therapy in the ab-P and cf-P arms, respectively (N = 197). Baseline patient characteristics were similar. The most common grade ≥3 taxane-related adverse events (AEs) were fatigue and neutropenia. Dose reductions were similar between the treatment arms. During AC therapy, the majority of dose reductions were due to febrile neutropenia; during taxane therapy, the majority of cases were due to neuropathy. No taxane-related dose interruption occurred in the ab-P arm, while 3 occurred in the cf-P arm due to hypersensitivity reactions. The mean cumulative paclitaxel dose was 950.5 and 660.8 mg/m(2) in the ab-P and cf-P arms, respectively. A 44% higher paclitaxel dose was delivered in the ab-P compared with the cf-P arm (P < 0.0001), while achieving a similar safety profile. ab-P plus bevacizumab following AC therapy without prophylactic premedications was tolerable in early-stage BC patients.

Carcinoma en cuirasse.

Carcinoma en cuirasse (CeC) is an extremely rare form of cutaneous metastasis of breast cancer. Guidelines for diagnosis and treatment of CeC are limited due to the small number of reported cases. It can be difficult to distinguish CeC from benign etiologies on initial presentation, but CeC can be easily distinguished by histopathology. Treatment of CeC focuses on palliation with no consensus on therapy guidelines. Treatment modalities that have been explored include chemotherapy, radiotherapy (with or without local hyperthermia), and hormonal antagonists. Here we present a 62-year-old woman with recurrent triple-negative breast cancer manifesting as CeC to the chest wall.

Clinico-radiologic features and management of hematological tumors in the breast: a case series.

Hematological tumors arising in the breast are uncommon and require different treatment modalities dependent upon tumor type. Current treatment options include surgical excision, chemotherapy, and radiotherapy. Management of these breast malignancies are poorly outlined in the literature. The purpose of this case series is to report five cases consisting of extranodal marginal zone lymphoma, lymphoplasmacytic lymphoma, and extramedullary plasmacytoma occurring in the breast. The cases illustrate heterogeneous radiologic findings and varying management approaches to these tumors. The case series underscores the importance of having a wide differential at diagnosis and recognizes management of disease should be taken on an individual basis with consideration of prognosis and first-line treatment options.

Giant malignant phyllodes tumor with metastasis to the brain.

We present the case of a 32-year-old African American woman with a giant malignant phyllodes tumor that metastasized to the lungs and subsequently the brain. Her treatment included six cycles of adjuvant therapy with AIM (Adriamycin®, ifosfamide, and mesna) followed by therapy with gemcitabine and docetaxel. A grand mal seizure led to discovery of a 6 × 5 × 5 cm brain mass which was resected. After resection, the patient developed pulmonary edema, repeat seizure activity, and massive intrathoracic progression before succumbing to her disease. This is an unpredictable and understudied neoplasm that can be aggressive and fatal in rare cases.

The effect of tamoxifen or exemestane on bone mineral density during the first 2 years of adjuvant treatment of postmenopausal women with early breast cancer.

BACKGROUND: Adjuvant therapy with aromatase inhibitors is associated with increased bone loss in postmenopausal women with breast cancer. We assessed changes in bone mineral density (BMD) from baseline to 24 months in patients receiving either tamoxifen (T) or exemestane (E). PATIENTS AND METHODS: A total of 578 women randomly assigned to T 20 mg per day orally or E 25 mg/day orally enrolled in this substudy; baseline, 12-month, and 24-month BMD measurements of the femur and lumbar spine by dual-energy x-ray absorptiometry were planned. Women receiving bone antiresorptive agents were excluded. Mean BMD changes from baseline to 12 and 24 months were tested between the treatment groups using 2-sample t tests and both g/cm2 (as percent changes) and T scores (as differences from baseline). RESULTS: A total of 167 women with all 3 imaging studies were evaluable and form the basis of this report (T=89, E=78). Using T scores, the mean difference from baseline was significant between the 2 groups at 12 months at both the spine (P=.0002) and the hip (P=.0004), and at 24 months only at the hip (P=.02). CONCLUSION: More bone loss occurred during the first 12 months of treatment with E compared with T, but by 2 years the differences were less apparent and bone loss with E had slowed.

Feasibility assessment of a chemoresponse assay to predict pathologic response in neoadjuvant chemotherapy for breast cancer patients.

BACKGROUND: For chemosensitivity and resistance assays to be clinically useful in predicting patient outcome, they should require small amounts of tissue and be highly reproducible and reliable. PATIENTS AND METHODS: Expanded tumor cells from transcutaneous biopsies of breast lesions (n=62) were tested for chemoresponse using the cell-based ChemoFx assay. Pathologic complete response (pCR) was determined on a subset of patients (n=34). Assay score and pCR were determined independently in a blinded manner. Logistic regression models were used to select predictors for response. RESULTS: Tumor cells were successfully isolated from 83.9% of patients. Chemoresponse profiles were robust and reproducible with coefficient of variance of <3%. In a limited initial patient outcome correlation, assay score of docetaxel/capecitabine significantly predicted pCR; the cross-validated model was 75% accurate. CONCLUSION: It is feasible to assess the chemoresponsiveness of small breast lesions using the ChemoFx assay to assist in choosing neoadjuvant chemotherapy for breast cancer patients.

Five-year results of a phase II trial of preoperative 5-fluorouracil, epirubicin, cyclophosphamide followed by docetaxel with capecitabine (wTX) (with trastuzumab in HER2-positive patients) for patients with stage II or III breast cancer.

We aimed to increase pathologic complete response (pCR) in patients with invasive breast cancer by adding preoperative capecitabine to docetaxel following 5-fluorouracil, epirubicin, cyclophosphamide (FEC) (with trastuzumab for patients with HER2-positive disease) and to evaluate 5-year disease-free survival (DFS) associated with this preoperative regimen. Chemotherapy included four cycles of FEC100 (5-fluorouracil 500 mg/m2 , epirubicin 100 mg/m2 , cyclophosphamide 500 mg/m2 IV on Day 1 every 21 days) followed by 4 21-day cycles of docetaxel (35 mg/m2  days 1 and 8) concurrently with capecitabine (825 mg/m2 orally twice daily for 14 days followed by 7 days off) (wTX). For HER2-positive patients, treatment was modified by decreasing epirubicin to 75 mg/m2 and adding trastuzumab (H) in standard doses (FEC75-H →wTX-H). The study objective was to achieve a pCR rate in the breast and axillary lymph nodes of 37% in patients with HER2-negative breast cancer and of 67% in patients with HER2-positive breast cancer treated with preoperative trastuzumab. A total of 186 patients were enrolled on study. In an intent-to-treat analysis, the pCR rate was 31% (37/118, 95% CI: 24-40%) in the HER2-negative patients, 24% (15/62, 95% CI: 14-37%) in ER-positive/HER2-negative patients, 39% (22/56, 95% CI: 27-53%) in the ER-negative/HER2-negative patients, and 46% (29/63, 95% CI: 34-48%) in the HER2-positive patients. The pCR rate in the 40 trastuzumab-treated patients was 53% (21/40, 95% CI: 38-67%). Grade 3 and 4 adverse events included neutropenia, leukopenia, diarrhea, and hand-foot skin reactions. One trastuzumab-treated patient developed grade 3 cardiotoxicity, and 4 others experienced grade 1-2 decrements in left ventricular function; all five patients' cardiac function returned to their baseline upon completion of trastuzumab. At 5 years, disease-free survival was 70% in the HER2-negative population (78% in ER-positive/HER2-negative and 62% in the ER-negative/HER2-negative patients) and 80% in the HER2-positive patients (87% in the trastuzumab-treated HER2-positive patients). At 5 years, overall survival was 80% in the HER2-negative population (88% in ER-positive/HER2-negative and 71% in the ER-negative/HER2-negative patients) and 86% in the HER2-positive patients (94.5% in the trastuzumab-treated HER2-positive patients). FEC100 (FEC75 with trastuzumab) followed by weekly docetaxel plus capecitabine, with or without trastuzumab is a safe, effective preoperative cytotoxic regimen. However, the addition of capecitabine to docetaxel following FEC, with or without trastuzumab, did not increase pCR rates nor 5-year DFS over the rates that have been reported with standard preoperative doxorubicin/cyclophosphamide (AC) followed by paclitaxel, with or without trastuzumab. Therefore, the use of capecitabine as part of preoperative chemotherapy is not recommended.

Phase II study of weekly albumin-bound paclitaxel for patients with metastatic breast cancer heavily pretreated with taxanes.

PURPOSE: Nanoparticle albumin-bound paclitaxel, a solvent-free, albumin-bound paclitaxel, demonstrated antitumor activity in patients with taxane-naive metastatic breast cancer (MBC). We examined albumin-bound paclitaxel (100 mg/m2 or 125 mg/m2 administered weekly) to determine the antitumor activity in patients with MBC whose disease progressed despite conventional taxane therapy. PATIENTS AND METHODS: Women with MBC that was previously treated with taxanes were eligible for participation. Taxane failure was defined as metastatic disease progression during taxane therapy or relapse within 12 months of adjuvant taxane therapy. Primary objectives were response rates (RRs) and the safety/tolerability of albumin-bound paclitaxel. RESULTS: Women were treated with albumin-bound paclitaxel 100 mg/m2 (n = 106) or 125 mg/m2 (n = 75) on days 1, 8, and 15 of a 28-day cycle. Response rates were 14% and 16% for the 100-mg/m2 and 125-mg/m2 cohorts, respectively; an additional 12% and 21% of patients, respectively, had stable disease (SD) > or = 16 weeks. Median progression-free survival times were 3 months at 100 mg/m2 and 3.5 months at 125 mg/m2; median survival times were 9.2 months and 9.1 months, respectively. Survival was similar for responding patients and those with SD. No severe hypersensitivity reactions were reported. Patients who developed treatment-limiting peripheral neuropathy typically could be restarted on a reduced dose of albumin-bound paclitaxel after a 1-2-week delay. Grade 4 neutropenia occurred in < 5% of patients. CONCLUSION: Albumin-bound paclitaxel 100 mg/m2 given weekly demonstrated the same antitumor activity as albumin-bound paclitaxel 125 mg/m2 weekly and a more favorable safety profile in patients with MBC that had progressed with previous taxane therapy. Survival of patients with SD > or = 16 weeks was similar to that of responders.

Two cancers in one: breast carcinoma with underlying melanoma.

A 61-year-old woman presented with a diagnosis of metastatic invasive lobular carcinoma of the right breast, and after treatment it had regressed or was stable except for a scalp nodule. When biopsied, the outer edges of the scalp lesion had findings consistent with breast carcinoma; however, the bulk of the tumor's pathology was consistent with melanoma. It appeared that most of the tumor was a highly vascularized melanoma with lobular breast carcinoma noted at its edges.

Time to response: comparison of fulvestrant and oral endocrine agents.

BACKGROUND: The different pharmacokinetic profiles of the intramuscularly administered antioestrogen fulvestrant and oral endocrine treatments have led to speculation among some physicians that this could result in a delayed time to response (TTR) with fulvestrant. PATIENTS AND METHODS: An analysis of TTR was performed on data from 2 phase III trials comparing fulvestrant and anastrozole as second-line treatments for postmenopausal women with advanced-stage, tamoxifen-resistant breast cancer. RESULTS: In a combined analysis of the data from these trials, median TTR was 3.1 months (range, 0.9-33.1 months) for fulvestrant and 3 months (range, 0.7-20.2 months) for anastrozole, although responses were still being noted after 2-3 years of stable disease in some patients. Data were subsequently analyzed from 3 other randomized phase III trials of fulvestrant, anastrozole, and tamoxifen in postmenopausal women. Time to response was also similar between the 3 treatments in these additional analyses. CONCLUSION: Time to response is similar between fulvestrant and oral endocrine treatments, despite pharmacokinetic differences.

Phase II, randomized, double-blind study of two dose levels of arzoxifene in patients with locally advanced or metastatic breast cancer.

PURPOSE: To select a daily dose of arzoxifene (LY353381), a selective estrogen receptor modulator, for use in future studies in women with locally advanced or metastatic breast cancer who are either potentially tamoxifen sensitive (TS) or tamoxifen refractory (TR). PATIENTS AND METHODS: This trial was a randomized, double-blind, phase II study of arzoxifene 20 mg (n = 55) and 50 mg (n = 57) in women with advanced or metastatic breast cancer. Patients were randomly assigned to balance for number of metastatic disease sites, prior tamoxifen therapy, and estrogen receptor status. The primary end point was tumor response rate (RR). Secondary end points included clinical benefit rate (CBR), time to progression (TTP), and toxicity. RESULTS: Forty-nine patients were TS and 63 were TR. According to independent review, among TS patients, RR was higher in the 20-mg arm than the 50-mg arm (26.1% v 8.0%), with a longer TTP (8.3 v 3.2 months; P >.05). Among the TR patients, response rate was the same in the 20-mg and 50-mg arms (10.3%) with similar TTP (2.7 and 2.8 months, respectively; P >.05). CBR was higher in the 20-mg arm than in the 50-mg arm among TS patients (39.1% v 20.0%) and TR patients (13.8% v 10.3%). Arzoxifene was well tolerated. Dose-dependent toxicity was not demonstrated. There were no deaths during study. CONCLUSION: Arzoxifene is effective in the treatment of TS and TR patients with advanced or metastatic breast cancer at the 20-mg and 50-mg dose levels. Toxicities are minimal, and the therapy is tolerated. The 20-mg dose seems to be at least as effective as the 50-mg dose. Accordingly, arzoxifene 20 mg/d was selected for further study in patients with breast cancer.

Effectiveness and tolerability of fulvestrant in postmenopausal women with hormone receptor-positive breast cancer.

Fulvestrant, an estrogen receptor antagonist that downregulates the estrogen receptor but has no known agonist effects, has been evaluated in 2 randomized trials involving postmenopausal women with hormone receptor-positive, progressive advanced-stage breast cancer after disease progression with antiestrogen therapy. These phase III studies, from which data were reported separately and in a planned combined analysis, showed that fulvestrant 250 mg per month intramuscularly was at least as effective as anastrozole 1 mg per day orally with respect to the primary endpoint of time to progression as well as secondary efficacy endpoints, which included objective response, clinical benefit, and survival. Both trials showed that patients treated with fulvestrant had a significantly longer duration of response, and a retrospective analysis found that pretreatment with fulvestrant did not preclude response to third-line hormonal therapy. More recently, fulvestrant was shown to be active as first-line hormonal therapy for advanced-stage breast cancer, with overall efficacy similar to that of tamoxifen in patients with hormone receptor-positive disease. Fulvestrant has been well tolerated in comparative trials published to date, translating into low study withdrawal rates and maintenance of quality of life. The incidence of adverse events was similar between the treatment arms in both trials of fulvestrant versus anastrozole, but it was notably lower for fulvestrant relative to tamoxifen in the first-line setting. In light of the results of comparative phase III trials, fulvestrant is effective and well tolerated in the treatment of postmenopausal women with hormone receptor-positive advanced-stage breast cancer.

Genomic alterations in DNA repair and chromatin remodeling genes in estrogen receptor-positive metastatic breast cancer patients with exceptional responses to capecitabine.

We analyzed the genomic and phosphoproteomic profiles of breast cancer tissue obtained from six patients with estrogen receptor (ER)-positive, HER2-negative metastatic breast cancer who had highly durable (≥ 5 years) and, in some cases, ongoing clinical responses with capecitabine. Formalin-fixed, paraffin-embedded tissue samples from patients' primary (n = 4) or metastatic (n = 2) breast cancers were utilized for targeted next-generation sequencing and reversed phase protein microarray. Two patients received capecitabine monotherapy. Four patients received capecitabine in combination with paclitaxel; three of these continued single-agent capecitabine after stopping paclitaxel. Capecitabine was discontinued for progressive disease after a mean of 66 months in four patients (range 54-86 months), and two patients remain on therapy, having received capecitabine for >91 months and >122 months, respectively. Three patients' cancers (50%) had likely functional alterations in DNA repair and chromatin remodeling genes, while three other patients' cancers had variants of unknown significance in these pathways. Mutations in PIK3CA, amplifications of FGFR1 or ZNF703, or phosphorylation of HER family receptors and their downstream proteins did not preclude exceptional responses to capecitabine. None of the patients' tumors harbored TP53 or PTEN mutations. Four of the patients had breast cancer tissue available for PTEN immunohistochemistry, and all four patients' cancers were positive for PTEN. These surprising findings in a group of phenotypically similar patients with ER-positive, endocrine therapy-pretreated, HER2-negative metastases, are supported by preclinical data showing that sensitivity to 5-fluorouracil is enhanced by deficiencies in chromatin remodeling and homologous recombination genes. Our findings suggest that mutations that inactivate homologous recombination and/or chromatin remodeling genes within ER-positive, HER2-negative breast cancers may predict for highly durable responses to capecitabine.

Patients with Slowly Proliferative Early Breast Cancer Have Low Five-Year Recurrence Rates in a Phase III Adjuvant Trial of Capecitabine.

PURPOSE: We conducted a randomized phase III study to determine whether patients with early breast cancer would benefit from the addition of capecitabine (X) to a standard regimen of doxorubicin (A) plus cyclophosphamide (C) followed by docetaxel (T). EXPERIMENTAL DESIGN: Treatment comprised eight cycles of AC→T (T dose: 100 mg/m(2) on day 1) or AC→XT (X dose: 825 mg/m(2) twice daily, days 1-14; T dose: 75 mg/m(2) on day 1). The primary endpoint was 5-year disease-free survival (DFS). RESULTS: Of 2,611 women, 1,304 were randomly assigned to receive AC→T and 1,307 to receive AC→XT. After a median follow-up of 5 years, the study failed to meet its primary endpoint [HR, 0.84; 95% confidence interval (CI), 0.67-1.05; P = 0.125]. A significant improvement in overall survival, a secondary endpoint, was seen with AC→XT versus AC→T (HR, 0.68; 95% CI, 0.51-0.92; P = 0.011). There were no unexpected adverse events. Of patients with estrogen receptor (ER)-positive/HER2-negative disease, 70% of whom were node-positive, 26% and 59% had tumors with a centrally assessed Ki-67 score of <10% or <20%, respectively, and only 17 (2%) and 53 (6%) DFS events, respectively, occurred in these groups at 7 years. CONCLUSIONS: The very low event rate in patients with ER-positive, low Ki-67 cancers, regardless of nodal status, strongly suggests that these patients should not be enrolled in adjuvant trials that assess 5-year DFS rates and that central Ki-67 analyses can identify these patients.

Pharmacokinetic profile of intramuscular fulvestrant in advanced breast cancer.

OBJECTIVE: To characterise the pharmacokinetics of a long-acting formulation of fulvestrant following intramuscular administration of single and multiple doses. STUDY DESIGN: Pharmacokinetic investigations of single and multiple doses of fulvestrant were conducted within two global phase III efficacy studies that compared intramuscular fulvestrant with oral anastrozole in postmenopausal women with hormone-sensitive advanced breast cancer (study 0020, conducted in Europe, Australia and South Africa, and study 0021, conducted in North America). METHODS: Patients received once-monthly intramuscular injections of fulvestrant 250 mg (1 x 5 mL for < or =21 months in study 0020; 2 x 2.5 mL for < or =30 months in study 0021). Serial blood samples were collected for the first 28 days after the initial dose and immediately prior to all subsequent monthly doses. Plasma fulvestrant concentrations were determined by high-performance liquid chromatography-tandem mass spectrometry. PATIENTS: Twenty-six (study 0020) and 193 (study 0021) postmenopausal women, comprising the pharmacokinetic subgroups of the phase III efficacy trials, were studied. Patients had shown disease progression or recurrence following previous hormonal therapy for advanced disease or had relapsed after adjuvant endocrine therapy with a nonsteroidal antiestrogen. OUTCOME MEASURES AND RESULTS: For single-dose fulvestrant 250 mg, area under the concentration-time curve from time zero to 28 days (AUC(28)), maximum observed plasma concentration (C(max)), minimum observed plasma concentration at 28 days (C(min)) and time to maximum plasma concentration (t(max)) were determined. For multiple-dose fulvestrant 250 mg once monthly, steady-state trough concentrations (C(trough)) were determined. Plasma fulvestrant concentrations reached a peak at a median of 7 days (range 2-8 days) postdose, and declined biexponentially with a slower phase commencing approximately 2-3 weeks postdose. Intersubject variability in C(max) and AUC(28) was approximately 6-fold and 4-fold, respectively. Mean parameters for single-dose fulvestrant were: AUC(28), 148 microg. day/L; C(max), 8.2 microg/L; C(min), 2.6 microg/L; t(max), 7.0 days. Geometric mean C(trough) increased from 2.57 to 6.15 microg/L (study 0020) and from 2.38 to 6.52 microg/L (study 0021) over the first 6 months, reaching steady-state concentrations of approximately 6-7 microg/L (study 0020) or 9 microg/L (study 0021). Preliminary pharmacokinetic analysis, using a naive pooled data approach, suggests that observed single- and multiple-dose plasma profiles can be adequately described with a two-compartment kinetic model. Model-generated steady-state AUC(28) values were approximately 300 microg. day/L. CONCLUSIONS: The intramuscular formulation of fulvestrant displays predictable kinetics and approximately 2-fold accumulation on administration once monthly. At the proposed therapeutic dosage (250 mg once monthly), plasma fulvestrant concentrations are maintained within a narrow range throughout the administration interval, thus ensuring stable systemic drug exposure during long-term treatment.

Phase II study of trastuzumab plus gemcitabine in chemotherapy-pretreated patients with metastatic breast cancer.

We evaluated the efficacy and toxicity of trastuzumab plus gemcitabine in patients with HER2-positive metastatic breast cancer (MBC). Sixty-four patients were enrolled, the majority of whom (95%) had been treated with an anthracycline and a taxane before study enrollment. Eligible women were treated with gemcitabine (1200 mg/m(2) weekly for 2 weeks with the third week off on a 21-day cycle) plus weekly doses of trastuzumab (4-mg/kg loading dose; 2 mg/kg thereafter) until disease progression. The median patient age was 55 years, and the median number of previously administered (including adjuvant) chemotherapy regimens was 3. Twenty-two patients were scored as 2+ for HER2 expression by immunohistochemistry; 39 patients scored 3+. Three patients were assessed as HER2-negative on central pathology review and were ineligible for evaluation. Fifty-nine of the 61 patients remained evaluable for response. The objective response rates were 38% in the intent-to-treat population (23 of 61) and 44% among the 39 patients with HER2 3+ expression. The median response duration was 5.8 months, median overall survival was 14.7 months, and median time to disease progression was 5.8 months. Trastuzumab plus gemcitabine was well tolerated. No cases of clinical congestive heart failure occurred. Grade 3/4 toxicities included asthenia in 4 patients, fever in 4, neutropenia in 18, dyspnea in 6, abdominal or back pain in 3, and edema and nausea in 1 patient each. The combination of trastuzumab plus gemcitabine appears to be well tolerated and effective for patients with HER2-positive MBC previously treated with chemotherapy.

Phase II trial of gemcitabine plus trastuzumab in metastatic breast cancer patients previously treated with chemotherapy: preliminary results.

Preliminary results of a phase II study of gemcitabine plus trastuzumab in previously treated (up to 3 previous regimens) metastatic breast cancer patients are presented. Patients had histologically confirmed metastatic breast cancer, with 2+ or 3+ tumor HER2 expression. Treatment consisted of gemcitabine 1200 mg/m2 over 30 minutes intravenously on days 1 and 8 every 21 days, and trastuzumab 4 mg/kg over 90 minutes, followed by 2 mg/kg infused over 30 minutes weekly. Treatment was continued until disease progression or unacceptable toxicity occurred. Preliminary results are available on the first 38 patients enrolled. Median patient age was 53 years, 53% had estrogen receptor/progesterone receptor-positive disease, and HER2 staining was 2+ in 39% and 3+ in 61% of patients. There was a median of 3 previously administered (including adjuvant) chemotherapy regimens, and a median of 4.5 treatment cycles per patient has been administered so far. Twelve patients (32%) have had an objective partial response, with a median response duration of 8.6 months. Median time to disease progression is 6.7 months to date, with a median overall survival of 10.2 months. No unexpected toxicities or grade 4 nonhematologic toxicities have been observed; 2 patients developed grade 4 neutropenia and 1 patient had febrile neutropenia. Thus, gemcitabine/ trastuzumab resulted in an encouraging 32% response rate, given the heavily pretreated patient population. Tolerability was good overall, with no unexpected side effects observed.