This phase III randomized open-label clinical trial was designed to evaluate the efficacy and safety of the steroidal aromatase inactivator exemestane versus the antiestrogen tamoxifen as first-line ...treatment for metastatic breast cancer (MBC) in postmenopausal women.
The study was conducted at 81 centers and enrolled postmenopausal patients with measurable hormone-sensitive metastatic or locally advanced breast cancer. Prior adjuvant chemotherapy and/or tamoxifen were allowed. One previous chemotherapy regimen and no prior hormone therapy for advanced disease were permitted. Patients were randomly assigned to receive exemestane 25 mg or tamoxifen 20 mg orally once daily until disease progression or unacceptable toxicity occurred.
A total of 371 patients enrolled at 79 sites (182 exemestane, 189 tamoxifen) were included in the analysis. Both treatments were generally well tolerated without major toxicity. Overall response rate was greater for exemestane than for tamoxifen treatment (46% v 31%; odds ratio = 1.85; 95% CI, 1.21 to 2.82; P = .005). Median progression-free survival (PFS) was longer with exemestane (9.9 months; 95% CI, 8.7 to 11.8 months) than with tamoxifen (5.8 months; 95% CI, 5.3 to 8.1 months). However, these early differences (Wilcoxon P = .028) did not translate to a longer-term benefit in PFS, the primary study end point (log-rank P = .121). There was also no difference in survival between both study arms.
Exemestane is an effective and well-tolerated first-line hormonal treatment for postmenopausal women with MBC and offers significant early improvement in time to tumor progression when compared with tamoxifen.
Neratinib is an oral, irreversible pan-ErbB receptor tyrosine kinase inhibitor. The efficacy and safety of neratinib were evaluated in two cohorts of patients with advanced ErbB2-positive breast ...cancer-those with and those without prior trastuzumab treatment-in an open-label, multicenter, phase II trial.
Patients in the two cohorts (prior trastuzumab, n = 66; no prior trastuzumab, n = 70) received oral neratinib 240 mg once daily. The primary end point was the 16-week progression-free survival (PFS) rate for the evaluable population (prior trastuzumab, n = 63; no prior trastuzumab, n = 64), as assessed by independent review.
The 16-week PFS rates were 59% for patients with prior trastuzumab treatment and 78% for patients with no prior trastuzumab treatment. Median PFS was 22.3 and 39.6 weeks, respectively. Objective response rates were 24% among patients with prior trastuzumab treatment and 56% in the trastuzumab-naïve cohort. The most common adverse events were diarrhea, nausea, vomiting, and fatigue. Diarrhea was the most frequent grades 3 to 4 adverse event, occurring in 30% of patients with prior trastuzumab treatment and in 13% of patients with no prior trastuzumab treatment, which prompted dose reductions in 29% and 4% of patients, respectively, but treatment discontinuation in only one patient. No neratinib-related, grades 3 or 4 cardiotoxicity was reported.
Oral neratinib showed substantial clinical activity and was reasonably well tolerated among both heavily pretreated and trastuzumab-naïve patients who had advanced, ErbB2-positive breast cancer. Diarrhea was the most common adverse effect but was manageable with antidiarrheal agents and dose modification.
To examine the association of baseline body mass index (BMI) with the risk of recurrence or death in postmenopausal women with early-stage breast cancer receiving adjuvant tamoxifen or letrozole in ...the Breast International Group (BIG) 1-98 trial at 8.7 years of median follow-up.
This report analyzes 4,760 patients with breast cancer randomly assigned to 5 years of monotherapy with letrozole or tamoxifen in the BIG 1-98 trial with available information on BMI at randomization. Multivariable Cox modeling assessed the association of BMI with disease-free survival, overall survival (OS), breast cancer-free interval, and distant recurrence-free interval and tested for treatment-by-BMI interaction. Median follow-up was 8.7 years.
Seventeen percent of patients have died. Obese patients (BMI ≥ 30 kg/m(2)) had slightly poorer OS (hazard ratio HR = 1.19; 95% CI, 0.99 to 1.44) than patients with normal BMI (< 25 kg/m(2)), whereas no trend in OS was observed in overweight (BMI 25 to < 30 kg/m(2)) versus normal-weight patients (HR = 1.02; 95% CI, 0.86 to 1.20). Treatment-by-BMI interactions were not statistically significant. The HRs for OS comparing obese versus normal BMI were HR = 1.22 (95% CI, 0.93 to 1.60) and HR = 1.18 (95% CI, 0.91 to 1.52) in the letrozole and tamoxifen groups, respectively.
There was no evidence that the benefit of letrozole over tamoxifen differed according to patients' BMI.
Four randomised controlled trials (RCTs) in postmenopausal women with advanced breast cancer (ABC) comparing aromatase inhibitors (AIs) versus the selective estrogen receptor modulator tamoxifen, ...each individually reported significantly longer progression-free survival (PFS) but none showed a significant difference in overall survival (OS). In these trials between 6.8% and 55% of tumours were hormone receptor (HR) status unknown or negative. This meta-analysis restricted the comparison to HR-positive (HR+) tumours.
Anonymised individual patient data were obtained from three RCTs, EORTC (exemestane versus tamoxifen), Study 0027 and Study 0030 (both anastrozole versus tamoxifen). For the remaining RCT (Femara Study PO25; letrozole versus tamoxifen), odds ratio (OR) or hazard ratio (HzR), with confidence intervals were obtained from the clinical study report, for patients with HR+ tumours, in addition to published data. In total, data were obtained from 2296 patients; 1560 (68%) had HR+ ABC.
The OR for clinical benefit rate was 1.56, in favour of AIs (p < 0.001). The duration of clinical benefit was not significantly increased by AIs (HzR 0·88; p = 0.08). For PFS the HzR (0.82) was in favour of AIs (p = 0·007). However, for OS the HzR (1.05) was not significantly different between AIs and tamoxifen (p = 0.42).
Although third generation AIs put significantly more patients into ‘clinical benefit’, their tumours were not controlled for significantly longer. Overall, while this resulted in a significantly greater PFS in favour of the AIs, this did not translate into improvement in OS.
•No overall survival benefit for AI over tamoxifen in HR+ advanced breast cancer.•Better PFS on AI due to more tumours in clinical benefit (CB), not longer duration of CB.•New approaches required for approving new drugs based on initial PFS data only.
Previous analyses of the Breast International Group (BIG) 1-98 four-arm study compared initial therapy with letrozole or tamoxifen including patients randomly assigned to sequential treatment whose ...information was censored at the time of therapy change. Because this presentation may unduly reflect early events, the present analysis is limited to patients randomly assigned to the continuous therapy arms and includes protocol-defined updated results.
Four thousand nine hundred twenty-two of the 8,028 postmenopausal women with receptor-positive early breast cancer randomly assigned (double-blind) to the BIG 1-98 trial were assigned to 5 years of continuous adjuvant therapy with either letrozole or tamoxifen; the remainder of women were assigned to receive the agents in sequence. Disease-free survival (DFS) was the primary end point.
At a median follow-up time of 51 months, we observed 352 DFS events among 2,463 women receiving letrozole and 418 events among 2,459 women receiving tamoxifen. This reflected an 18% reduction in the risk of an event (hazard ratio, 0.82; 95% CI, 0.71 to 0.95; P = .007). No predefined subsets showed differential benefit. Adverse events were similar to previous reports. Patients on tamoxifen experienced more thromboembolic events, endometrial pathology, hot flashes, night sweats, and vaginal bleeding. Patients on letrozole experienced more bone fractures, arthralgia, low-grade hypercholesterolemia, and cardiovascular events other than ischemia and cardiac failure.
The present updated analysis, which was limited to patients on monotherapy arms in BIG 1-98, yields results similar to those from the previous primary analysis but more directly comparable with results from other trials of continuous therapy using a single endocrine agent.
Summary Background Aromatase inhibitors improved disease-free survival compared with tamoxifen when given as an initial adjuvant treatment or after 2–3 years of tamoxifen to postmenopausal women with ...hormone-receptor-positive breast cancer. We therefore compared the long-term effects of exemestane monotherapy with sequential treatment (tamoxifen followed by exemestane). Methods The Tamoxifen Exemestane Adjuvant Multinational (TEAM) phase 3 trial was conducted in hospitals in nine countries. Postmenopausal women (median age 64 years, range 35–96) with hormone-receptor-positive breast cancer were randomly assigned in a 1:1 ratio to open-label exemestane (25 mg once a day, orally) alone or following tamoxifen (20 mg once a day, orally) for 5 years. Randomisation was by use of a computer-generated random permuted block method. The primary endpoint was disease-free survival (DFS) at 5 years. Main analyses were by intention to treat. The trial is registered with ClinicalTrials.gov , NCT00279448 , NCT00032136 , and NCT00036270 ; NTR 267 ; Ethics Commission Trial 27/2001 ; and UMIN , C000000057. Findings 9779 patients were assigned to sequential treatment (n=4875) or exemestane alone (n=4904), and 4868 and 4898 were analysed by intention to treat, respectively. 4154 (85%) patients in the sequential group and 4186 (86%) in the exemestane alone group were disease free at 5 years (hazard ratio 0·97, 95% CI 0·88–1·08; p=0·60). In the safety analysis, sequential treatment was associated with a higher incidence of gynaecological symptoms (942 20% of 4814 vs 523 11% of 4852), venous thrombosis (99 2% vs 47 1%), and endometrial abnormalities (191 4% vs 19 <1%) than was exemestane alone. Musculoskeletal adverse events (2448 50% vs 2133 44%), hypertension (303 6% vs 219 5%), and hyperlipidaemia (230 5% vs 136 3%) were reported more frequently with exemestane alone. Interpretation Treatment regimens of exemestane alone or after tamoxifen might be judged to be appropriate options for postmenopausal women with hormone-receptor-positive early breast cancer. Funding Pfizer.
The activity and safety of eribulin mesylate (E7389), a nontaxane microtubule dynamics inhibitor with a novel mechanism of action, were evaluated in patients with locally advanced or metastatic ...breast cancer previously treated with an anthracycline, taxane, and capecitabine.
Eligible patients in this single-arm, open-label phase II study received eribulin mesylate (1.4 mg/m(2)) administered as a 2- to 5-minute intravenous infusion on days 1 and 8 of a 21-day cycle. The primary end point was objective response rate (ORR) assessed by independent review.
Of 299 enrolled patients who had received a median of four prior chemotherapy regimens, 291 received eribulin (for a median of four cycles). Of these, 269 patients met key inclusion criteria for the primary efficacy analysis. The primary end point of ORR by independent review was 9.3% (95% CI, 6.1% to 13.4%; all partial responses PRs), the stable disease (SD) rate was 46.5%, and clinical benefit rate (complete response + PR + SD > or = 6 months) was 17.1%. The investigator-reported ORR was 14.1% (95% CI, 10.2% to 18.9%). Median duration of response was 4.1 months, and progression-free survival was 2.6 months. Median overall survival was 10.4 months. The most common treatment-related grade 3 or 4 toxicities were neutropenia (54%; febrile neutropenia, 5.5%), leukopenia (14%), and asthenia/fatigue (10%; no grade 4); grade 3 neuropathy occurred in 6.9% of patients (no grade 4).
Eribulin demonstrated antitumor activity in extensively pretreated patients who had previously received an anthracycline, taxane, and capecitabine, with a manageable tolerability profile.
Overall survival (OS) can be observed only after prolonged follow-up, and any potential effect of first-line therapies on OS may be confounded by the effects of subsequent therapy. We investigated ...whether tumor response, disease control, progression-free survival (PFS), or time to progression (TTP) could be considered a valid surrogate for OS to assess the benefits of first-line therapies for patients with metastatic breast cancer.
Individual patient data were collected on 3,953 patients in 11 randomized trials that compared an anthracycline (alone or in combination) with a taxane (alone or in combination with an anthracycline). Surrogacy was assessed through the correlation between the end points as well as through the correlation between the treatment effects on the end points.
Tumor response (survival odds ratio OR, 6.2; 95% CI, 5.3 to 7.0) and disease control (survival OR, 5.5; 95% CI, 4.8 to 6.3) were strongly associated with OS. PFS (rank correlation coefficient, 0.688; 95% CI, 0.686 to 0.690) and TTP (rank correlation coefficient, 0.682; 95% CI, 0.680 to 0.684) were moderately associated with OS. Response log ORs were strongly correlated with PFS log hazard ratios (linear coefficient rho, 0.96; 95% CI, 0.73 to 1.19). Response and disease control log ORs and PFS and TTP log hazard ratios were poorly correlated with log hazard ratios for OS, but the confidence limits of rho were too wide to be informative.
No end point could be demonstrated as a good surrogate for OS in these trials. Tumor response may be an acceptable surrogate for PFS.
Specific adverse events (AEs) associated with endocrine therapy and related to depletion or blocking of circulating estrogens may be related to treatment efficacy. We investigated the relationship ...between survival outcomes and specific AEs including vasomotor symptoms (VMSs), musculoskeletal adverse events (MSAEs), and vulvovaginal symptoms (VVSs) in postmenopausal patients with breast cancer participating in the international Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial.
Primary efficacy end points were disease-free survival (DFS), overall survival (OS), and distant metastases (DM). VMSs, MSAEs, and VVSs arising in the first year of endocrine treatment were considered. Patients who did not start or who discontinued their allocated therapy and/or had an event (recurrence/death) within 1 year after randomization were excluded. Landmark analyses and time-dependent multivariate Cox proportional hazards models assessed survival differences up to 5 years from the start of treatment.
A total of 9,325 patients were included. Patients with specific AEs (v nonspecific or no AEs) had better DFS and OS (multivariate hazard ratio HR for DFS: VMSs, 0.731 95% CI, 0.618 to 0.866; MSAEs, 0.826 95% CI, 0.694 to 0.982; VVSs, 0.769 95% CI, 0.585 to 1.01; multivariate HR for OS: VMSs, 0.583 95% CI, 0.424 to 0.803; MSAEs, 0.811 95% CI, 0.654 to 1.005; VVSs, 0.570 95% CI, 0.391 to 0.831) and fewer DM (VMSs, 0.813 95% CI, 0.664 to 0.996; MSAEs, 0.749 95% CI, 0.601 to 0.934; VVSs, 0.687 95% CI, 0.436 to 1.085) than patients not reporting these symptoms. Increasing numbers of specific AEs were also associated with better survival outcomes. Outcomes were unrelated to treatment allocation.
Certain specific AEs are associated with superior survival outcomes and may therefore be useful in predicting treatment responses in patients with breast cancer treated with endocrine therapy.
To explore potential differences in efficacy, treatment completion, and adverse events (AEs) in elderly women receiving adjuvant tamoxifen or letrozole for five years in the Breast International ...Group (BIG) 1-98 trial.
This report includes the 4,922 patients allocated to 5 years of letrozole or tamoxifen in the BIG 1-98 trial. The median follow-up was 40.4 months. Subpopulation Treatment Effect Pattern Plot (STEPP) analysis was used to examine the patterns of differences in disease-free survival and incidences of AEs according to age. In addition, three categoric age groups were defined: "younger postmenopausal" patients were younger than 65 years (n = 3,127), "older" patients were 65 to 74 years old (n = 1,500), and "elderly" patients were 75 years of age or older (n = 295).
Efficacy results for subpopulations defined by age were similar to the overall trial results: Letrozole significantly improved disease-free survival (DFS), the primary end point, compared with tamoxifen. Elderly patients were less likely to complete trial treatment, but at rates that were similar in the two treatment groups. The incidence of bone fractures, observed more often in the letrozole group, did not differ by age. In elderly patients, letrozole had a significantly higher incidence of any grade 3 to 5 protocol-specified non-fracture AE compared with tamoxifen (P = .002), but differences were not significant for thromboembolic or cardiac AEs.
Adjuvant treatment with letrozole had superior efficacy (DFS) compared with tamoxifen in all age groups. On the basis of a small number of patients older than 75 years (6%), age per se should not unduly affect the choice of adjuvant endocrine therapy.
PDF
