Pooled ctDNA analysis of MONALEESA phase III advanced breast cancer trials

BACKGROUND

The phase III MONALEESA trials tested the efficacy and safety of the cyclin-dependent kinase (CDK)4/6 inhibitor ribociclib with different endocrine therapy partners as first- or second-line treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer (ABC). Using the largest pooled biomarker dataset of the CDK4/6 inhibitor ribociclib in ABC to date, we identified potential biomarkers of response to ribociclib.

PATIENTS AND METHODS

Baseline circulating tumour DNA from patients in the MONALEESA trials was assessed using next-generation sequencing. An analysis of correlation between gene alteration status and progression-free survival (PFS) was carried out to identify potential biomarkers of response to ribociclib.

RESULTS

Multiple frequently altered genes were identified. Alterations in ERBB2, FAT3, FRS2, MDM2, SFRP1, and ZNF217 were associated with a greater PFS benefit with ribociclib versus placebo. Patients with high tumour mutational burden (TMB) and with ANO1, CDKN2A/2B/2C, and RB1 alterations exhibited decreased sensitivity to ribociclib versus placebo.

CONCLUSIONS

Although exploratory, these results provide insight into alterations associated with the improved response to ribociclib treatment and may inform treatment sequencing in patients with actionable alterations following progression on CDK4/6 inhibitors. Validation of potential biomarkers identified here and development of prospective trials testing their clinical utility are warranted.

CLINICALTRIALS

GOV IDENTIFIERS

NCT01958021, NCT02422615, NCT02278120.

Ribociclib plus fulvestrant for postmenopausal women with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer in the phase III randomized MONALEESA-3 trial: updated overall survival

BACKGROUND

Ribociclib plus fulvestrant demonstrated significant progression-free survival (PFS) and overall survival (OS) benefits in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer (ABC). Here we present a new landmark in survival follow-up for a phase III cyclin-dependent kinases 4 and 6 inhibitor clinical trial in patients with ABC (median, 56.3 months).

PATIENTS AND METHODS

This phase III, randomized, double-blind, placebo-controlled trial was conducted at 174 sites (30 countries). Patients were men and postmenopausal women (age ≥18 years) with histologically/cytologically confirmed HR+/HER2- ABC. Patients could have received ≤1 line of endocrine therapy (ET) but no chemotherapy for ABC. Patients, assigned 2:1, were stratified by the presence/absence of liver/lung metastases and previous ET. Patients received intramuscular fulvestrant (500 mg, day 1 of each 28-day cycle plus day 15 of cycle 1) with oral ribociclib (600 mg/day, 3 weeks on, 1 week off) or placebo. Efficacy analyses were by intention to treat. Safety was assessed in patients receiving ≥1 dose study treatment. OS was a secondary endpoint. MONALEESA-3 is registered with ClinicalTrials.gov (NCT02422615; no longer enrolling).

RESULTS

Between 18 June 2015 and 10 June 2016, 726 patients were randomly assigned (484, ribociclib; 242, placebo). At data cut-off (30 October 2020), median OS (mOS) was 53.7 months (ribociclib) versus 41.5 months (placebo) [hazard ratio (HR), 0.73; 95% confidence interval (CI) 0.59-0.90]. Subgroup analyses were consistent with overall population. In the first-line setting, most patients in the ribociclib arm (∼60%) lived longer than median follow-up; mOS was 51.8 months in the placebo arm (HR, 0.64; 95% CI 0.46-0.88). In the second-line setting, mOS was 39.7 months (ribociclib) versus 33.7 months (placebo) (HR, 0.78; 95% CI 0.59-1.04). No apparent drug-drug interaction between ribociclib and fulvestrant or new safety signals were observed.

CONCLUSIONS

This analysis reported extended OS follow-up in MONALEESA-3. mOS was ∼12 months longer in patients with HR+/HER2- ABC treated with ribociclib plus fulvestrant compared with fulvestrant monotherapy.

Abstract P4-13-12: Everolimus plus trastuzumab and vinorelbine for trastuzumab-resistant, taxane-pretreated, HER2+ advanced breast cancer: Overall survival results from BOLERO-3

Background

PI3K/AKT/mTOR pathway activation due to PTEN loss may lead to trastuzumab (TRAS) resistance. mTOR inhibition has been shown to restore TRAS sensitivity in PTEN-deficient tumors. This provided the rationale for the BOLERO-3 trial which evaluated the combination of everolimus (EVE), an mTOR inhibitor, plus TRAS and a taxane in HER2+ advanced breast cancer (ABC). The addition of EVE to TRAS plus vinorelbine (VNB) led to a statistically significant prolongation of 1.2 months in median progression free survival (PFS) vs TRAS plus VNB in patients with TRAS-resistant and taxane-pretreated, HER2+ ABC (7.0 months vs 5.78 months; hazard ratio, 0.78; p=0.0067). The final overall survival (OS) analysis from this study is presented here.

Materials and methods

BOLERO-3 is a randomized, double-blind, placebo-controlled, phase 3 trial. Women with HER2+ ABC progressing on prior TRAS and taxane therapy were randomized (1:1) to receive either daily EVE (5 mg) or PBO plus weekly TRAS (2 mg/kg) and VNB (25 mg/m2), in 3-week cycles, stratified by previous lapatinib use. The primary endpoint was PFS by local investigator assessment. Overall survival was a key secondary endpoint.

Results

Overall, 569 patients were enrolled; 284 patients received EVE and 285 patients received PBO. As of April 1, 2015, after a median follow-up of 44.7 months, 388 deaths had occurred, 191 (67.3%) in the EVE arm and 197 (69.1%) in the PBO arm. The median OS in the EVE arm vs PBO arm was 23.5 months vs 24.1 months (HR = 0.96; 95% CI, 0.79-1.17; p = 0.3392). In the HR+ subgroup, the median OS with EVE was 23.5 months (vs 25.5 months with PBO; HR = 1.03; 95% CI, 0.79-1.35); in the HR subgroup, the median OS with EVE was 22.9 months (vs 23.1 months with PBO; HR = 0.86; 95% CI, 0.64-1.17). AEs leading to treatment discontinuation were reported in 81 (28.9%) vs 46 (16.3%) patients in the EVE vs PBO arms. Serious adverse events (SAEs) were reported in 122 (43.6%) vs 58 (20.6%) patients in the EVE vs PBO arms. Overall, 14 on-treatment deaths were observed, 7 (2.5%) in the EVE arm and 7 (2.5%) in the PBO arm; on-treatment deaths due to AEs were balanced between treatment arms (0.7% in each treatment arm). Types of post-progression therapies were balanced across both treatment arms.

Conclusions

In BOLERO-3, EVE showed a statistically significant prolongation of PFS. OS was similar in both treatment arms. The safety profile of EVE was comparable to that observed previously with EVE in breast cancer. (Funded by Novartis; BOLERO-3 ClinicalTrials.gov number, NCT01007942.)

Citation Format: Isaacs C, O'Regan R, Xu B, Masuda N, Arena F, Yap Y-S, Papai Z, Lang I, Armstrong A, Lerzo G, White M, Shen K, Zhang Y, Jappe A, Pacaud LB, Taran T, Ozguroglu M. Everolimus plus trastuzumab and vinorelbine for trastuzumab-resistant, taxane-pretreated, HER2+ advanced breast cancer: Overall survival results from BOLERO-3. [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 P4-13-12.

Everolimus plus exemestane for hormone-receptor-positive, human epidermal growth factor receptor-2-negative advanced breast cancer: overall survival results from BOLERO-2†

BACKGROUND

The BOLERO-2 study previously demonstrated that adding everolimus (EVE) to exemestane (EXE) significantly improved progression-free survival (PFS) by more than twofold in patients with hormone-receptor-positive (HR(+)), HER2-negative advanced breast cancer that recurred or progressed during/after treatment with nonsteroidal aromatase inhibitors (NSAIs). The overall survival (OS) analysis is presented here.

PATIENTS AND METHODS

BOLERO-2 is a phase III, double-blind, randomized international trial comparing EVE 10 mg/day plus EXE 25 mg/day versus placebo (PBO) + EXE 25 mg/day in postmenopausal women with HR(+) advanced breast cancer with prior exposure to NSAIs. The primary end point was PFS by local investigator assessment; OS was a key secondary end point.

RESULTS

At the time of data cutoff (3 October 2013), 410 deaths had occurred and 13 patients remained on treatment. Median OS in patients receiving EVE + EXE was 31.0 months [95% confidence interval (CI) 28.0-34.6 months] compared with 26.6 months (95% CI 22.6-33.1 months) in patients receiving PBO + EXE (hazard ratio = 0.89; 95% CI 0.73-1.10; log-rank P = 0.14). Poststudy treatments were received by 84% of patients in the EVE + EXE arm versus 90% of patients in the PBO + EXE arm. Types of poststudy therapies were balanced across arms, except for chemotherapy (53% EVE + EXE versus 63% PBO + EXE). No new safety concerns were identified.

CONCLUSIONS

In BOLERO-2, adding EVE to EXE did not confer a statistically significant improvement in the secondary end point OS despite producing a clinically meaningful and statistically significant improvement in the primary end point, PFS (4.6-months prolongation in median PFS; P < 0.0001). Ongoing translational research should further refine the benefit of mTOR inhibition and related pathways in this treatment setting.

TRIAL REGISTRATION NUMBER

NCT00863655.

Stomatitis incidence and its relationship with efficacy: A meta-analysis of everolimus clinical studies

151

Background: The most common adverse event (AE) with everolimus (EVE) is stomatitis. This meta-analysis evaluated the incidence, severity, and possible impact of stomatitis on efficacy in patients (pts) with cancer or tuberous sclerosis complex (TSC) who received EVE. Methods: Stomatitis events from 7 randomized, double-blind, phase 3 EVE studies included: RECORD-1 (RCC), RADIANT-2 (NET), RADIANT-3 (pNET), BOLERO-2 (HR+/HER2- breast cancer [BC]), BOLERO-3 (HER2+BC), and EXIST-1 and -2 (TSC). Time to first stomatitis occurrence and recurrence were analyzed using Kaplan-Meier (KM) methods. Stratified Cox regression analysis adjusted for baseline prognostic factors and corrected for confounding effect of duration of exposure was used to analyze association between stomatitis occurrence (≤ 8 wks of EVE start) and PFS in pts with cancer and response rate in pts with TSC. Results: This evaluation included EVE-treated pts with cancer (n = 1,455) and TSC (n = 157). Pts with cancer had stomatitis incidence of 66.9%, which occurred early, median 0.82 mo (95% CI, 0.7-1.0; 2-mo KM estimate 60.8%). 8.6% were grade 3/4 events. 1.7% of pts discontinued due to stomatitis. Stomatitis recurred in 40% of pts and appeared gradually. In pts with TSC similar results were observed. In EVE-treated pts, development of stomatitis was associated with longer PFS (corrected HR [95% CI]) in BOLERO-2 (0.78 [0.62-1.00]) and RADIANT-3 (0.70 [0.48-1.01]), and similar trend was observed in RECORD-1 (0.90 [0.66-1.22]) and RADIANT-2 (0.87 [0.61-1.22]), but not in BOLERO-3. In TSC, probably due to few pts, relationship between stomatitis and response was not conclusive. In all trials, pts on EVE had longer PFS vs placebo irrespective of stomatitis incidence. Conclusions: Stomatitis is observed frequently in initial wks of EVE therapy. Most AEs were grade 1/2 and manageable, rarely led to pt discontinuation. Stomatitis recurred in < 50% of pts. EVE-treated pts with cancer who had stomatitis achieved stable benefit similar to overall population, suggesting that continuing EVE is helpful. The importance of prophylactic measures in reducing EVE-induced stomatitis incidence and improving its management is being determined by ongoing studies.

Incidence and time course of everolimus-related adverse events in postmenopausal women with hormone receptor-positive advanced breast cancer: insights from BOLERO-2

BACKGROUND

In the BOLERO-2 trial, everolimus (EVE), an inhibitor of mammalian target of rapamycin, demonstrated significant clinical benefit with an acceptable safety profile when administered with exemestane (EXE) in postmenopausal women with hormone receptor-positive (HR(+)) advanced breast cancer. We report on the incidence, time course, severity, and resolution of treatment-emergent adverse events (AEs) as well as incidence of dose modifications during the extended follow-up of this study.

PATIENTS AND METHODS

Patients were randomized (2:1) to receive EVE 10 mg/day or placebo (PBO), with open-label EXE 25 mg/day (n = 724). The primary end point was progression-free survival. Secondary end points included overall survival, objective response rate, and safety. Safety evaluations included recording of AEs, laboratory values, dose interruptions/adjustments, and study drug discontinuations.

RESULTS

The safety population comprised 720 patients (EVE + EXE, 482; PBO + EXE, 238). The median follow-up was 18 months. Class-effect toxicities, including stomatitis, pneumonitis, and hyperglycemia, were generally of mild or moderate severity and occurred relatively early after treatment initiation (except pneumonitis); incidence tapered off thereafter. EVE dose reduction and interruption (360 and 705 events, respectively) required for AE management were independent of patient age. The median duration of dose interruption was 7 days. Discontinuation of both study drugs because of AEs was higher with EVE + EXE (9%) versus PBO + EXE (3%).

CONCLUSIONS

Most EVE-associated AEs occur soon after initiation of therapy, are typically of mild or moderate severity, and are generally manageable with dose reduction and interruption. Discontinuation due to toxicity was uncommon. Understanding the time course of class-effect AEs will help inform preventive and monitoring strategies as well as patient education.

TRIAL REGISTRATION NUMBER

NCT00863655.

Abstract P3-15-03: Safety analysis of BOLERO-3: A phase 3 trial of daily everolimus (EVE) vs placebo (PBO), both with weekly trastuzumab (TRAS) and vinorelbine in trastuzumab-resistant, advanced breast cancer

Background: Activation of the PI3K/mTOR pathway is thought to be involved in resistance to TRAS. BOLERO-3 is a randomized phase 3, double-blind, placebo-controlled, international, clinical trial evaluating the addition of the mTOR inhibitor EVE (5 mg/day) to TRAS plus vinorelbine (25 mg/m2) in patients with HER2+ advanced breast cancer resistant to TRAS and who were previously treated with a taxane. A total of 569 adult women were randomized 1:1 to receive EVE (n = 284) or PBO (n = 285). Study treatment represented the 2nd, 3rd, or 4th line of chemotherapy-containing regimen for 83% of patients in the metastatic setting. The primary endpoint, progression-free survival based on local radiologic assessment, was significantly longer in the EVE arm versus PBO (HR = 0.78; P = .0067) at a median follow-up of 20 months.

Methods: Study drugs were continued until disease progression or unacceptable toxicity. Incidences of adverse events (AEs) were monitored continuously. Dose modifications and discontinuations were recorded.

Results: The median duration of exposure to study treatment was similar across treatment groups: 24.8 weeks for EVE, 25.1 weeks for TRAS, and 24.0 weeks for vinorelbine (EVE arm); and 22.9 weeks for PBO, 24.0 weeks for TRAS, and 23.1 weeks for vinorelbine (PBO arm). The AEs were consistent with known drug-safety profiles. Class-effect AEs with mTOR inhibitors (including stomatitis, rash, noninfectious pneumonitis, and hyperglycemia) were higher in the EVE arm and were mainly grade 1/2. Grade 3 class-effect AEs each occurred in &lt;15% of patients (stomatitis [13%], hyperglycemia [2%], and noninfectious pneumonitis [&lt;1%]). Grade 4 noninfectious pneumonitis (&lt;1%) was uncommon; there were no grade 4 events of stomatitis or hyperglycemia, and no grade 3/4 events of rash. The incidence and grade of hematologic AEs were increased in the EVE arm vs the PBO arm, including all grade neutropenia (81% vs 70%), anemia (49% vs 29%), febrile neutropenia (17% vs 4%) and thrombocytopenia (14% vs 2%); grade 3/4 hematologic AEs included neutropenia (grade 3: 35% vs 32%; grade 4: 38% vs 30%), anemia (grade 3: 17% vs 6%; grade 4: 2% vs &lt;1%), febrile neutropenia (grade 3: 11% vs 3%; grade 4: 5% vs 1%), and thrombocytopenia (grade 3: 3% vs &lt;1%; grade 4: 1% vs 0). The incidences and grades of changes in liver enzymes and hyperlipidemia were similar between arms. Serious AEs were reported in 42% of patients in the EVE arm and 20% of patients in the PBO arm (26% and 6% were attributed to study treatments, respectively). A higher percentage of patients discontinued treatment because of AEs in the EVE arm versus PBO (10% vs 5%). In all, 83% of patients required at least 1 EVE dose interruption and/or reduction; 96% of these were attributed to AEs. There were fewer deaths in the EVE arm (37%) compared with PBO (41%).

Conclusions: The safety of the combination of EVE, TRAS, and vinorelbine was considered manageable in this heavily pretreated patient population. Overall, the results from BOLERO-3 demonstrate that EVE can be combined with TRAS and chemotherapy to improve efficacy in TRAS-resistant HER2+ advanced breast cancer previously treated with a taxane.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-15-03.

Abstract P4-12-19: BOLERO-3: Everolimus plus trastuzumab and vinorelbine in Asian patients with HER2-positive metastatic breast cancer

Background: Resistance to trastuzumab may occur through activation of the PI3K/Akt/mTOR signaling pathway, the inhibition of which may restore trastuzumab sensitivity. BOLERO-3, a phase 3, double-blind, international trial involving 569 patients with trastuzumab-resistant, HER2-positive (HER2+), advanced breast cancer pretreated with a taxane, recently reported that adding everolimus (EVE; an mTOR inhibitor) to vinorelbine and trastuzumab significantly improved progression-free survival (PFS) vs placebo (PBO) plus vinorelbine and trastuzumab (hazard ratio [HR] = 0.78; log-rank P = .0067). As EVE pharmacokinetics and, therefore, clinical effects may be different in Asian patients, we analyzed the efficacy and safety data from BOLERO-3 for the Asian population.

Methods: Eligible women with trastuzumab-resistant, HER2+, advanced breast cancer who received prior taxane therapy were randomized (1:1) to EVE (5 mg/day) or matching PBO in combination with weekly vinorelbine (25 mg/m2) and trastuzumab (2 mg/kg after 4-mg/kg loading dose). The primary endpoint was PFS by investigator. Secondary endpoints included safety.

Results: Among 569 patients enrolled in this study, 166 (29%) patients were Asian; 88 and 78 were assigned to EVE or PBO arms, respectively. In this subpopulation, adding EVE to vinorelbine and trastuzumab prolonged median PFS compared with the PBO arm (8.3 vs 6.8 months, respectively; HR = 0.83; 95% confidence interval, 0.59 - 1.18). In general, the incidence of all grade adverse events was similar for Asian versus non-Asian patients in the EVE arm (stomatitis, 71% vs 59%; pneumonitis, 7% vs 5%; and infections, 58% vs 70%) and the PBO arm (stomatitis, 31% vs 26%; pneumonitis, 1% vs 4%; and infections, 48% vs 49%). Serious adverse events had a low incidence and included febrile neutropenia (9.1%), neutropenia (2.3%), stomatitis (2.3%), anemia (2.3%), and cataract (2.3%) as the most common among Asian patients in the EVE arm. The incidence of serious pneumonitis was low: Asian (1.1%) versus non-Asian patients (0%) in the EVE arm and 0% versus 1.5%, respectively, in the PBO arm.

Conclusions: Asian patients in the BOLERO-3 trial treated with EVE plus vinorelbine and trastuzumab showed PFS benefits similar to the overall population and had a comparable manageable safety profile. Thus, EVE in combination with vinorelbine and trastuzumab may be considered as a new therapeutic option for Asian women with trastuzumab-resistant, HER2+, advanced breast cancer progressing after taxane-based therapies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-19.

Abstract P4-12-18: BOLERO-3: Quality-of-life maintained in patients with metastatic breast cancer treated with everolimus plus trastuzumab plus vinorelbine

Background: Activation of the PI3K/mTOR pathway is implicated in resistance to trastuzumab. Accordingly, the BOLERO-3 study evaluated the efficacy of adding everolimus (EVE), an mTOR inhibitor, to vinorelbine and trastuzumab. At the final progression-free survival (PFS) analysis, EVE significantly improved PFS vs PBO (hazard ratio [HR] = 0.78; log-rank P = .0067) but EVE-treated patients had higher rate of grade 3/4 toxicity. To further qualify the benefit:risk of adding EVE to trastuzumab-based therapy, per-protocol, patient-reported, health-related quality-of-life (HRQoL) data were analyzed.

Methods: BOLERO-3 is a randomized phase 3, double-blind, placebo-controlled, international multicenter trial. Taxane-pretreated patients (N = 569) with trastuzumab-resistant, HER2+, advanced breast cancer were randomized (1:1) to treatment with EVE or placebo (PBO) plus vinorelbine and trastuzumab. The European Organisation for Research and Treatment of Cancer (EORTC) quality-of-life questionnaire C30 (QLQ-C30) (including the breast cancer-specific BR23 module) was administered at baseline and every 6 weeks thereafter until progression. The QLQ-C30 consists of 30 items combined into 15 subscales, including Global Health Status and functional subscales, where higher scores (range, 0 to 100) indicate better HRQoL. Time to definitive deterioration (TTD) based on a 10% decrease from baseline for GHS and for the physical, emotional, and social function subscales was determined using the Kaplan-Meier method. Treatment arms were compared using a 2-sided log-rank test stratified by prior use of lapatinib.

Results: Overall, there was no significant difference in median TDD of HRQoL between treatment arms. The median TTD in global health status score was 8.3 months for EVE (95% confidence interval [CI], 6.9-11.5) vs 7.3 months for PBO (95% CI, 5.6-10.4; P = .8386). The median TTD in the physical, emotional, and social function subscale scores showed no significant difference between arms. For example, median TTD in the physical function subscale score was 12.0 months (95% CI, 8.3-14.1) for EVE vs 12.5 months (95% CI, 8.3-20.9) for PBO (P = .4251), and median TTD in the emotional function subscale score was 15.2 months (95% CI, 9.2-17.3) for EVE vs 12.5 months (95% CI, 9.7-16.4) for PBO (P = .8140).

Conclusions: These analyses demonstrate that, despite increased frequency of adverse events observed with the addition of EVE to the standard treatment of vinorelbine and trastuzumab, overall and functional HRQoL scores were not negatively impacted in patients with trastuzumab-resistant, HER2+, advanced breast cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-18.

Abstract P2-16-17: Characterization of response to everolimus (EVE) in BOLERO-2: A phase 3 trial of EVE plus exemestane (EXE) in postmenopausal women with HR+, HER2- advanced breast cancer

Introduction: The BOLERO-2 trial demonstrated that combining the oral mammalian target of rapamycin (mTOR) inhibitor, EVE, with the steroidal aromatase inhibitor, EXE, more than doubled median progression-free survival (PFS) compared with placebo (PBO) plus EXE in postmenopausal women with hormone-receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2−) breast cancer (BC) who relapsed or progressed following a nonsteroidal aromatase inhibitor (NSAI). Patients also achieved responses per Response Evaluation Criteria in Solid Tumors (RECIST) during treatment with EVE+EXE.

Methods: The phase 3, double-blind, BOLERO-2 trial randomized postmenopausal women with HR+ BC progressing or recurring after NSAIs in a 2:1 manner to EVE 10 mg once daily plus EXE 25 mg once daily (EVE+EXE; n = 485) or placebo (PBO) plus EXE (PBO+EXE; n = 239). The primary endpoint was PFS by local assessment. Overall response rate (ORR; complete + partial response per investigator assessment based on RECIST 1.0) and duration of overall response were secondary endpoints. In addition, best percentage change from baseline in sum of longest diameters of target lesions was assessed.

Results: At the time of final PFS analyses at 18 months’ median follow-up, ORR was significantly higher in the EVE+EXE arm compared with the PBO+EXE arm (12.6% vs 1.7%, respectively, by local assessment; P&lt;.0001). Among patients with measurable disease at baseline, 71% in the EVE+EXE arm had a decrease in the sum of longest diameters of target lesions compared with baseline vs 30% in the PBO+EXE arm. Median duration of overall response was 10.5 months (95% confidence interval [CI]: 8.2, 21.9 months) for EVE+EXE and 6.9 months (95% CI: 4.2, 6.9 months) for PBO+EXE. Of note, only 4 patients in the PBO+EXE arm had an objective response to treatment.

Conclusions: In addition to PFS, the combination of EVE plus EXE significantly improved ORR vs PBO+EXE in patients with HR+, HER2− advanced BC progressing during or after NSAI therapy. Furthermore, greater than two-thirds of patients treated with EVE+EXE experienced tumor shrinkage during treatment. These results further support the rationale for combining EVE with EXE to improve clinical outcomes in HR+, HER2− advanced BC progressing after NSAI therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-17.

BOLERO-2: Efficacy and safety of first-line everolimus plus exemestane in advanced breast cancer

152

Background: In the BOLERO-2 study, progression-free survival (PFS) was significantly longer with the combination of everolimus and exemestane (EVE + EXE) compared with placebo and exemestane (PBO + EXE; hazard ratio = 0.45; p < .0001). Consistent efficacy results were observed in all subgroup analyses, such as in patients with visceral metastases and patients with disease recurrence during/after adjuvant therapy. This analysis of BOLERO-2 examines the efficacy of EVE + EXE in the subgroup of patients who received treatment immediately after recurrence during adjuvant therapy (i.e., as first-line therapy in the advanced setting). Methods: BOLERO-2 enrolled patients with hormone receptor–positive (HR+) advanced breast cancer with disease recurrence or progression after prior nonsteroidal aromatase inhibitors and compared EVE (10 mg/d) + EXE (25 mg/d) vs PBO + EXE. The primary end point was PFS by local investigator review. Results: A total of 137 patients received first-line EVE + EXE (n = 100) or PBO + EXE (n = 37) in the advanced setting. Of these patients, 74% of the EVE + EXE arm and 76% of the PBO + EXE arm had recurred after adjuvant endocrine therapy plus chemotherapy; 26% and 24%, respectively, had recurred after adjuvant endocrine therapy alone. Also, approximately 20% of patients entered the trial after recurring during or within 12 months of adjuvant therapy (21% EVE + EXE vs 16% PBO + EXE). The EVE + EXE group had significantly longer PFS compared with the PBO + EXE group (11.50 vs 4.07 months, respectively; hazard ratio = 0.39; 95% confidence interval, 0.25-0.62). Median PFS remained longer with EVE + EXE versus PBO + EXE, regardless of whether chemotherapy was included with the prior adjuvant hormonal therapy. Similar results were obtained from the analyses based on central review. The safety profile was consistent with the known profiles of each agent. Conclusions: EVE + EXE prolonged PFS in patients with HR+ advanced breast cancer who received treatment as first-line therapy. These results support the combination of EVE + EXE in patients with recurrence after adjuvant therapy. The recently initiated BOLERO-4 study is also evaluating the efficacy of EVE as a first-line therapy in patients with HR+ advanced breast cancer. Clinical trial information: NCT00863655.

Characterization of patients who received prior chemotherapy for advanced breast cancer (ABC) in BOLERO-2

151

Background: In patients with hormone receptor–positive (HR+) breast cancer, endocrine therapy is the standard of care both in the adjuvant setting and as front-line therapy for ABC. Chemotherapy (CT) is commonly used for HR+ ABC patients if disease burden is high and rapid symptom control is required (Barrios CH. GAMO. 2010). In the phase III BOLERO-2 study (NCT00863655), first-line of prior CT in the ABC setting was allowed. This subset analysis examined disease characteristics and the efficacy of everolimus (EVE) + exemestane (EXE) in patients who received CT for ABC prior to BOLERO-2 study entry. Methods: In BOLERO-2, 724 patients with HR+, human epidermal growth factor receptor 2–negative (HER2–) ABC whose disease recurred or progressed during/after a nonsteroidal aromatase inhibitor were randomized 2:1 to EVE (10 mg/d) + EXE (25 mg/d) or placebo (PBO) + EXE. The primary endpoint was progression-free survival (PFS) by local investigator review (confirmed by blinded independent central review). Results: A total of 186 patients (26%) received prior CT for ABC (125 in the EVE + EXE group and 61 in PBO + EXE). In this subset, 54% (67 of 125) of EVE+ EXE patients received prior CT in the advanced setting only while 46% (58 of 125) of EVE + EXE patients received prior CT in both the neoadjuvant/adjuvant and advanced settings. Visceral metastases (67% vs. 56%), multiple metastases (79% vs. 66%), and ≥ 4 metastatic sites (18% vs. 15%) were more frequent in ABC patients with prior CT for ABC at study entry compared with those with no prior CT for ABC. History of disease recurrence <6 months from initial diagnosis was recorded in 32% (n = 60) of prior CT patients versus 17% (n = 93) of patients with no prior CT. Median PFS (by local assessment) in patients who received prior CT for ABC was substantially longer with EVE + EXE versus PBO + EXE (6.1 vs. 2.7 mo; hazard ratio = 0.38; 95% CI, 0.27-0.53). PFS by central review showed similar results (7.1 vs. 2.8 mo, respectively; hazard ratio = 0.42; 95% CI, 0.27-0.65). Conclusions: These results demonstrate that patients with HR+, HER2 ABC who received previous CT in the advanced setting had a higher tumor burden but derived significant and clinically meaningful benefit from combination therapy with EVE + EXE. Clinical trial information: NCT00863655.

Patient-reported physical, emotional, and social functioning in advanced breast cancer: Insights from BOLERO-2

155

Background: The phase III BOLERO-2 study at 18 months’ median follow-up showed that everolimus (EVE) + exemestane (EXE) significantly improved progression-free survival (PFS) vs EXE alone in 724 patients with hormone receptor–positive (HR+) advanced breast cancer (ABC) with recurrence/progression during/after nonsteroidal aromatase inhibitor (NSAI) therapy. A higher rate of grade 3/4 adverse events was noted with EVE + EXE but was not associated with deterioration in quality of life (QOL) based on the EORTC QLQ-C30 Global Health Status scale. Additional patient-reported post hoc analyses of QOL are reported herein. Methods: During BOLERO-2, QOL (EORTC QLQ-C30 and QLQ-BR23) was assessed at baseline and q 6 wk thereafter until progression or discontinuation. Physical, emotional, and social functioning subscales of QLQ-C30 were analyzed. Time to definitive deterioration (TTD) was defined based on either a 5% (protocol-specified) or a 10-point (more stringent) decrease from baseline for each subscale and analyzed by Kaplan-Meier methods. The difference between treatments was assessed by a log-rank test stratified by randomization factors. Results: QLQ-C30 compliance was >80% at week 48. Among the 3 protocol-specified QLQ-C30 subscales, analyses based on a 5% decrease in QOL showed a longer TTD for both physical and emotional functioning in the EVE + EXE group vs EXE alone (log-rank p = 0.0120 and p = 0.0277, respectively). The TTDs for social functioning were similar in both treatment arms (log-rank p = 0.3374). Analyses based on a 10-point decrease indicated a longer TTD for physical functioning in the EVE + EXE group (15.2 mo) vs EXE alone (9.7 mo; log-rank p = 0.0211). The TTDs for emotional and social functioning were similar between EVE + EXE and EXE alone: 13.9 vs 13.8, respectively (log-rank p = 0.4023), and 11.5 vs 9.5, respectively (log-rank p = 0.2507). Conclusions: The treatment goal for ABC is to maximize clinical benefit with minimal negative effects on QOL. These additional BOLERO-2 QOL analyses confirmed that the more than doubling of PFS with EVE + EXE was accompanied by maintained physical, emotional, and social functioning compared with EXE alone in patients with HR+ ABC progressing after NSAI. Clinical trial information: NCT00863655.

Correlation of molecular alterations with efficacy of everolimus in hormone-receptor–positive, HER2-negative advanced breast cancer: Results from BOLERO-2

142

Background: Everolimus (EVE) plus exemestane (EXE) more than doubled progression-free survival (PFS) while maintaining quality of life vs EXE alone in postmenopausal women with hormone receptor–positive (HR+), HER2-negative (HER2–) advanced breast cancer (BOLERO-2 phase III; NCT00863655). PFS benefit was seen in all clinically defined subgroups. We evaluated genetic variations of a broad panel of cancer-related genes and explored their correlations with EVE benefit. Methods: Exon sequence and gene copy number variations were analyzed in 182 cancer-related genes by next-generation sequencing (NGS). Correlations with PFS were evaluated using univariate and multivariate Cox models. Results: NGS data (>250x coverage) were successfully generated from archival tumor specimens from 227 patients (NGS population, 157 in EVE + EXE arm and 70 in EXE arm) whose baseline characteristics and clinical outcome were comparable to the trial population (PFS HR = 0.40 and 0.45, respectively). The treatment benefit of EVE + EXE over EXE was maintained in the subgroups defined by each of the 9 genes with a mutation rate >10% (e.g., PIK3CA, FGFR1, CCND1) or when less frequently mutated genes (e.g., PTEN, AKT1) were included in their respective pathways. Patients with 0 or 1 genetic alteration in PI3K or FGFR pathways or CCND1 had a greater treatment effect from EVE (HR = 0.27, 95% CI 0.18-0.41, adjusted by covariates, in 76% of the NGS population), indicating the value of these pathways for predicting sensitivity to EVE in this setting. Conclusions: This is the first global registration trial in which efficacy-predictive biomarkers were explored by correlating broad genetic variations with clinical efficacy. The preliminary results suggest that a large subgroup of patients (76%), defined by minimal genetic variations in the PI3K or FGFR pathways or CCND1, derives the most benefit from EVE therapy (HR = 0.27 vs 0.40 for the full NGS population). These exploratory results and their implication in understanding the interplay of multiple pathways in tumor cells and testing new hypotheses for targeted combination therapies in HR+/HER2– BC will be further investigated. Clinical trial information: NCT00863655.

Correlation of molecular alterations with efficacy of everolimus in hormone receptor–positive, HER2-negative advanced breast cancer: Results from BOLERO-2

LBA509

Background: Everolimus (EVE) plus exemestane (EXE) more than doubled progression-free survival (PFS) while maintaining quality of life vs EXE alone in postmenopausal women with hormone-receptor positive (HR+), HER2-negative (HER2-) advanced breast cancer (BOLERO-2 phase III; NCT00863655). PFS benefit was seen in all clinically defined subgroups. We evaluated genetic variations of a broad panel of cancer-related genes and explored their correlations with EVE benefit. Methods: Exon sequence and gene copy number variations were analyzed in 182 cancer-related genes by next-generation sequencing (NGS). Correlations with PFS were evaluated using both univariate and multivariate Cox models. Results: NGS data (>250x coverage) were successfully generated from archival tumor specimens from 227 patients (NGS population, 157 and 70 in EVE+EXE and EXE arms, respectively) whose baseline characteristics and clinical outcome were comparable with the trial population (PFS HR = 0.40 and 0.45, respectively). The treatment benefit of EVE+EXE over EXE is maintained in the subgroups defined by each of the nine genes with a mutation rate >10% (eg, PIK3CA, FGFR1, and CCND1), or when less frequently mutated genes (eg, PTEN, AKT1) were included in their respective pathways. Patients with no or only 1 genetic alteration in PI3K or FGFR pathways, or CCND1, had a greater treatment effect from EVE (HR = 0.27, 95% CI 0.18-0.41, adjusted by covariates, in 76% of the NGS population), indicating the value of these pathways for predicting sensitivity/resistance to EVE in this setting. Conclusions: This is the first global registration trial in which efficacy-predictive biomarkers were explored by correlating broad genetic variations with clinical efficacy. It demonstrated the feasibility of applying large-scale NGS and subsequent correlative analysis to such trials. The observations suggest that a large subgroup of patients (76%), defined by minimal genetic variations in the PI3K or FGFR pathways, or CCND1, derives the most benefit from EVE therapy (HR = 0.27 vs 0.40 for the full NGS population). These exploratory results and their implication in understanding the interplay of multiple pathways in tumor cells and testing new hypotheses for targeted combination therapies in HR+/HER2- BC will be further investigated. Clinical trial information: NCT00863655.

Characterization of patients who received prior chemotherapy for advanced breast cancer (ABC) in BOLERO-2

557

Background: In patients with hormone-receptor–positive (HR+) breast cancer, endocrine therapy is the standard of care both in the adjuvant setting and as first-line treatment for ABC. For selected HR+ patients with ABC, chemotherapy (CT) may be utilized if disease burden is high and rapid symptom control is required (Barrios CH. GAMO.2010). In the phase 3 BOLERO-2 study (NCT00863655), 1 line of prior CT in the ABC setting was allowed. This subset analysis examined disease characteristics and the efficacy of everolimus (EVE) plus exemestane (EXE) in patients who received CT for ABC prior to BOLERO-2 study entry. Methods: In BOLERO-2, 724 patients with HR+, human epidermal growth factor receptor-2–negative (HER2–) ABC whose disease recurred or progressed during/after a nonsteroidal aromatase inhibitor were randomized 2:1 to EVE (10 mg/d) + EXE (25 mg/d) or placebo (PBO) + EXE. The primary endpoint was progression-free survival (PFS) by local investigator review and confirmed by blinded independent central review. Results: A subset of 186 patients (26%) received prior CT for ABC: 125 in the EVE + EXE group and 61 in PBO + EXE. In this subset, 54% (67 of 186) of patients received prior CT only in the advanced setting and 46% (58 of 186) of patients received prior CT in both the neoadjuvant/adjuvant and advanced settings. Incidences of visceral metastases (67% vs 56%), multiple metastases (79% vs 66%), and ≥ 4 metastatic sites (18.3% vs 15%) were higher in ABC patients with prior CT for ABC at study entry versus those with no prior CT for ABC. Disease recurrence < 6 months from initial diagnosis was recorded in 32.2% (n = 60) of prior CT patients versus 17.3% (n = 93) of patients with no prior CT. Median PFS (by local assessment) in patients who received prior CT for ABC was substantially longer with EVE + EXE versus PBO + EXE (6.1 vs 2.7 mo; HR = 0.38; 95% CI, 0.27-0.53). PFS by central review showed similar results (7.1 vs 2.8 mo, respectively; HR = 0.42; 95% CI, 0.27-0.65). Conclusions: These results demonstrate that patients with HR+, HER2– ABC who received previous CT in the advanced setting had a higher tumor burden and derived clinically significant benefit from combination treatment with EVE + EXE. Clinical trial information: NCT00863655.

Clinical management and resolution of stomatitis in BOLERO-2

558

Background: In BOLERO-2, adding everolimus (EVE) to exemestane (EXE) more than doubled progression-free survival without affecting quality of life vs EXE alone in postmenopausal women with hormone-receptor–positive advanced breast cancer who had recurrence or progression on/after nonsteroidal aromatase inhibitor therapy. Although mTOR inhibitors are generally well tolerated, stomatitis is one of their most clinically relevant and potentially dose-limiting toxicities (Sonis Cancer2010). The incidence, grade, and clinical course of stomatitis among patients (pts) participating in the BOLERO-2 study are described. Methods: Pts were randomized 2:1 to receive EVE+EXE or placebo (PBO)+EXE. Stomatitis incidence, severity, consequent dose interruptions/adjustments, study drug discontinuations, and time to resolution were recorded. Results: The median duration of EVE+EXE treatment exposure was 30 wk (range, 1-123 wk). Stomatitis (any grade) occurred more frequently with EVE+EXE than with PBO+EXE (59% vs 12%, respectively). Grade 3 stomatitis occurred in 8% vs 1% of pts receiving EVE+EXE vs PBO+EXE, respectively; no grade 4 was reported. Onset of grade ≥2 stomatitis after treatment initiation was earlier in the EVE+EXE arm vs the PBO+EXE arm: median time was 15d vs 24d, respectively. In the EVE+EXE arm, 97% of pts with grade 3 stomatitis (n=38) improved to ≤1 after a median of 13 d. Complete resolution was observed in 82% of these pts after a median of 38 d. In the PBO+EXE arm, all pts with grade 3 stomatitis (n=2) improved to ≤1 after a median of 18 d. Complete resolution was observed after a median of 29 d. Overall, 24% of pts in the EVE+EXE arm required dose interruptions/adjustments vs 1% of pts in the PBO+EXE arm, and 3% of pts (n=13) discontinued EVE+EXE vs <1% of pts (n=1) discontinuing PBO+EXE, all related to stomatitis. Conclusions: The BOLERO-2 data foster a new era of combining targeted and endocrine therapies. In the study, treatment-emergent stomatitis was of mild to moderate intensity, occurred shortly after treatment initiation, and was generally reversible. Most incidents were successfully managed with palliative interventions and temporary dose modifications. Oral hygiene and other preventive measures are recommended. Clinical trial information: NCT00863655.

Phase III, randomized, double-blind, placebo-controlled multicenter trial of daily everolimus plus weekly trastuzumab and vinorelbine in trastuzumab-resistant, advanced breast cancer (BOLERO-3)

505

Background: Everolimus (EVE) is an inhibitor of mammalian target of rapamycin (mTOR), a protein kinase central to a number of signaling pathways regulating cell growth and proliferation. Data from preclinical and phase 1/2 clinical studies indicated that adding EVE to trastuzumab (TRAS) plus chemotherapy may restore sensitivity to and enhance efficacy of human epidermal growth factor receptor 2 (HER2)-targeted therapy. The international BOLERO-3 phase 3 study is being conducted to evaluate the addition of EVE to TRAS plus vinorelbine. Methods: Adult women with HER2+ advanced breast cancer and who received prior taxane therapy and experienced recurrence or progression on TRAS were randomized 1:1 to receive either EVE or placebo (5 mg/day) in combination with weekly TRAS and vinorelbine (25 mg/m2). The primary endpoint is progression-free survival (PFS). Secondary endpoints included overall survival, response rate, clinical benefit rate, safety, quality of life, and pharmacokinetics. Final analysis will be conducted after approximately 417 PFS events. Results: The trial accrued 569 patients between October 2009 and May 2012. Previous therapy included TRAS (100%), a taxane (100%), and lapatinib (28%). The median age was 54 years, and 76% of patients had visceral metastases, 5% had stable brain metastases, 56% had hormone-receptor–positive disease, 33% had Eastern Cooperative Oncology Group performance status of 1 or 2, and 41% had 3 or more metastatic sites. The median number of prior chemotherapy lines in the metastatic setting was 1. As of February 4, 2013, a total of 396 PFS events were reported. Conclusions: Final PFS analysis will be performed in early May 2013; primary and secondary efficacy endpoints will be presented. Clinical trial information: NCT01007942.

Incidence, management, and resolution of noninfectious pneumonitis in BOLERO-2

561

Background: The BOLERO-2 trial showed that adding everolimus (EVE) to exemestane (EXE) more than doubled progression-free survival (PFS) without reducing quality of life versus placebo (PBO) + EXE alone in postmenopausal women with hormone-receptor–positive (HR+), HER2-negative (HER2–) advanced breast cancer (ABC) progressing on/after nonsteroidal aromatase inhibitor (NSAI) therapy. Although generally well tolerated, mTOR inhibitors such as EVE have been associated with noninfectious pneumonitis (NIP). Methods: Patients (pts) were randomized 2:1 to receive EVE+EXE or PBO+EXE. Incidence and severity of NIP, consequent dose interruptions/adjustments, study drug discontinuations, and time to resolution were recorded. Results: Median duration of exposure to EVE was 24 weeks with median dose intensity of 8.6 mg/d. Pulmonary adverse events (AEs) of any grade (NIP, interstitial lung disease, lung infiltration, pneumonia, or pulmonary fibrosis) were recorded in 97 of 482 pts (20%) in the EVE+EXE arm versus 1 of 238 pts (<1%) in the PBO+EXE arm. Of these, 16% of pts (77 of 482) in the EVE+EXE arm versus 0 in the PBO+EXE arm had a diagnosis consistent with NIP. In the EVE+EXE arm, grade 1 (no symptoms), grade 2 and 3 NIP occurred in 7%, 6% and 3% of pts, respectively, and no grade 4 events were reported. Complete resolution of NIP to grade ≤1 was recorded for all but 4 pts for whom NIP was still observed at last follow-up before study discontinuation. Overall, in the EVE+EXE arm, NIP was recorded as the reason for dose interruption and treatment discontinuation in 7.5% and 5.6% of pts, respectively. Conclusions: Data from BOLERO-2 support the combination of EVE and EXE to significantly prolong PFS in postmenopausal women with HR+, HER2– ABC progressing on/after NSAI. The incidence of NIP in this study was generally consistent with reports from other oncology settings, was of mild to moderate severity, and was generally reversible with appropriate interventions and temporary dose modifications. Patient and healthcare provider education for early diagnosis and management of NIP are highly recommended. Clinical trial information: NCT00863655.

Correlation of molecular alterations with efficacy of everolimus in hormone-receptor–positive (HR+), HER2-negative advanced breast cancer: Preliminary results from BOLERO-2

LBA509

The full, final text of this abstract will be available at abstract.asco.org at 7:30 AM (EDT) on Monday, June, 3, 2013, and in the Annual Meeting Proceedings online supplement to the June 20, 2013, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Monday edition of ASCO Daily News.

BOLERO-6: Phase II study of everolimus plus exemestane versus everolimus or capecitabine monotherapy in HR+, HER2- advanced breast cancer

TPS660

Background: Everolimus (EVE), an orally bioavailable inhibitor of the mammalian target of rapamycin (mTOR), has shown clinical activity as monotherapy and in combination with endocrine therapy (ET) in hormone-receptor–positive (HR+; estrogen and/or progesterone receptors) advanced breast cancer (ABC). In a pivotal phase 3 trial in patients with HR+ ABC progressing on ET, EVE + exemestane (EXE) significantly prolonged median progression-free survival (PFS) vs EXE alone per local (7.8 vs 3.2 months; log-rank P<.0001) or central (11.0 months for EVE+EXE vs 4.1 months for EXE alone; log-rank P<.0001) assessment. Capecitabine, an orally administered fluoropyrimidine carbamate indicated as monotherapy in paclitaxel and/or anthracycline-refractory ABC, has shown clinical benefit in patients with HR+, human epidermal growth factor receptor 2-negative (HER2-) ABC. The BOLERO-6 study in patients with HR+, HER2- ABC progressing on prior anastrozole or letrozole will compare PFS following EVE+EXE combination therapy vs EVE or capecitabine monotherapy. Methods: In this multicenter, open-label, randomized, 3-arm, phase 2 study, 300 patients will be randomized to receive either EVE (10 mg/d) + EXE (25 mg/d) combination therapy, or EVE (10 mg/d) alone, or capecitabine (1,250 mg/m2twice daily for 14 d/3-wk cycle) alone, until disease progression. Patients will be stratified based on the presence of visceral disease. Key eligibility criteria include age ≥18 years, postmenopausal status; histologic or cytologic confirmation of estrogen-receptor–positive, HER2- ABC; radiologic or objective evidence of recurrence or progression on prior aromatase inhibitors; Eastern Cooperative Oncology Group (ECOG) performance status ≤2. The primary endpoint is PFS with EVE+EXE vs EVE, based on local radiologic assessment (Response Evaluation Criteria in Solid Tumors [RECIST] 1.1). The key secondary endpoint is PFS with EVE+EXE vs capecitabine. Other secondary endpoints include overall survival, objective response rate, clinical benefit rate, safety, quality of life, and patient satisfaction with treatment. Enrollment will start in Q1 2013. Estimated study completion in Q1 2015. Clinical trial information: NCT01783444.

Patient-reported physical, emotional, and social functioning in advanced breast cancer: Insights from BOLERO-2

553

Background: The phase 3 BOLERO-2 study at 18 months’ median follow-up showed that everolimus (EVE) + exemestane (EXE) significantly improved progression-free survival (PFS) vs EXE alone in 724 hormone-receptor–positive (HR+) advanced breast cancer (ABC) patients with recurrence/progression during/after nonsteroidal aromatase inhibitor (NSAI) therapy. A higher rate of grade 3/4 adverse events was noted with EVE + EXE, but was not associated with deterioration in quality of life (QOL) based on the EORTC QLQ-C30 Global Health Status scale. Additional patient-reported post hoc analyses of QOL are reported herein. Methods: During BOLERO-2, QOL (EORTC QLQ-C30 and QLQ-BR23) was assessed at baseline and q 6 wk thereafter until progression or discontinuation. Physical, emotional, and social functioning subscales of QLQ-C30 were analyzed. Time to definitive deterioration (TTD) was defined based on either a 5% (protocol specified) or 10-point (more stringent) decrease from baseline for each subscale and analyzed by Kaplan-Meier methods. The difference between treatments was assessed by a log-rank test stratified by randomization factors. Results: QLQ-C30 compliance was > 80% at week 48. Among the 3 protocol-specified QLQ-C30 subscales, analyses based on a 5% decrease in QOL showed a longer TTD for both physical and emotional functioning in the EVE + EXE group vs EXE alone (log-rank P = .0120 and P = .0277, respectively). The TTD for social functioning was similar in both treatment arms (log-rank P = .3374). Analyses based on a 10-point decrease indicated a longer TTD for physical functioning in the EVE + EXE group (15.2 mo) vs EXE alone (9.7 mo; log-rank P = .0211). The TTDs for emotional and social functioning were similar between EVE + EXE and EXE alone: 13.9 vs 13.8, respectively (log-rank P = .4023), and 11.5 vs 9.5, respectively (log-rank P = .2507). Conclusions: The treatment goal for ABC is to maximize clinical benefit with minimal negative effects on QOL. These additional BOLERO-2 QOL analyses confirmed that the more than doubling of PFS with EVE + EXE was accompanied by maintained physical, emotional, and social functioning compared with EXE alone in patients with HR+ ABC progressing after NSAI. Clinical trial information: NCT00863655.

Effects of everolimus (EVE) on disease progression in bone and bone markers (BMs) in patients (pts) with bone metastases (mets)

102

Background: BOLERO-2, a multinational, double-blind, placebo-controlled, phase III study in postmenopausal women with estrogen-receptor–positive breast cancer (BC) refractory to nonsteroidal aromatase inhibitors (NSAIs), showed significant clinical benefits with the addition of EVE to exemestane (EXE) (Baselga J et al. NEJM2011 Epub). As bone resorption is an important factor in BC mets, it is interesting to study bone-related effects of EVE. In preclinical studies, mTOR inhibition was associated with decreased osteoclast survival and activity. Exploratory analyses in BOLERO-2 evaluated the effects of EVE vs placebo (PBO) on BM levels and BC progression in bone in pts with bone mets at baseline. Methods: Eligible pts were treated with EXE (25 mg once daily) and randomized (2:1) to EVE (10 mg once daily) or PBO. Bone turnover markers (BMs) were exploratory endpoints analyzed at 6 and 12 wks after treatment initiation and included bone-specific alkaline phosphatase, amino-terminal propeptide of type I collagen, and C-terminal cross-linking telopeptide of type I collagen. Progressive disease in bone (PDB) was defined as worsening of a preexisting bone lesion or a new bone lesion. Results: Baseline disease characteristics, including bone mets at baseline (n = 370, 76% EVE vs n = 184, 77% PBO), were well balanced between arms (N = 724), and baseline bisphosphonate use was not (44% EVE vs 55% PBO). At 12.5 mo median follow-up, progression-free survival (primary endpoint), overall response rate, and clinical benefit rate (p < 0.0001, all) were significantly higher with EVE (n = 485) vs PBO (n = 239). BM levels at 6 and 12 wks increased vs baseline with PBO but decreased with EVE. The cumulative incidence rate of BC PBD was lower for EVE vs PBO at day 60 (3.03% vs 6.16%, respectively), and this trend was sustained beyond 6 months. Updated results will be presented. All bone-related adverse events reported were grade 1-2 and occurred with similar frequency in EVE (2.9%)- and PBO (3.8%)-treated patients. Conclusions: Exploratory analyses from BOLERO-2 suggest that adding EVE has beneficial effects on bone turnover and BC progression in bone in pts receiving EXE therapy for NSAI-refractory BC.

Safety of everolimus for women over age 65 with advanced breast cancer (BC): 12.5-month follow-up of BOLERO-2

104

Background: Postmenopausal women with estrogen-receptor–positive (ER+) BC who relapse/progress on a nonsteroidal aromatase inhibitor (NSAI) are usually treated with the steroidal AI exemestane (EXE), but there is no currently approved treatment for this indication. The BOLERO-2 trial showed that adding everolimus (EVE), an oral inhibitor of mammalian target of rapamycin (mTOR), to EXE significantly improved clinical benefit beyond that of EXE alone (Hortobagyi et al, SABCS 2011, Abstract S3-7). As many women with advanced BC are elderly, the tolerability profile of EVE + EXE in this population is of interest. Methods: BOLERO-2 is a phase III, randomized trial comparing EVE (10 mg once daily) vs placebo (PBO), both plus EXE (25 mg once daily), in postmenopausal women with advanced ER+ BC progressing or recurring after NSAIs. Safety data with a focus on elderly patients are reported at 12.5 months’ median follow-up. Results: Baseline disease characteristics, age, and prior cancer therapy were well balanced between treatment arms (N = 724). At 12.5 months’ median follow-up, the addition of EVE to EXE significantly improved progression-free survival in patients <65 (HR, 0.37; p < .05) or ≥65 years of age (HR, 0.56; p < .05). Adverse events (AEs) of special interest (all grades) occurring more frequently with EVE vs PBO (overall study population) included stomatitis (66.6% vs 11.3%), infection (50.4% vs 25.2%), rash (44.0% vs 8.4%), pneumonitis (18.7% vs 0.4%), and hyperglycemia (15.4% vs 2.5%). Elderly EVE-treated patients (≥65 years) had similar or marginally lower incidence of stomatitis (52.1%), rash (32.3%), pneumonitis (14.6%), and hyperglycemia (12.5%) compared with the overall population. Grade 3-4 AEs in patients ≥70 years of age (n = 161) reported only among patients receiving EVE (n = 118) included fatigue (10.2%), anemia (10.2%), hyperglycemia (8.5%), stomatitis (7.6%), dyspnea (6.8%), pneumonitis (5.1%), neutropenia (3.4%), and hypertension (3.4%). Conclusions: Adding EVE to EXE was well tolerated in the overall population and in elderly patients with advanced BC; grade 3-4 AEs were uncommon and manageable. Overall, AEs were consistent with the known safety profile of EVE.

Everolimus for postmenopausal women with advanced breast cancer: Updated results of the BOLERO-2 phase III trial

99

Background: Current treatment options for postmenopausal patients with estrogen-receptor–positive breast cancer (BC) who relapse or progress on a nonsteroidal aromatase inhibitor (NSAI) are limited. The BOLERO-2 trial supports the activity of everolimus (EVE; an oral mammalian target of rapamycin [mTOR] inhibitor) added to the steroidal aromatase inhibitor exemestane (EXE) to prolong progression-free survival (PFS) in this patient population. Long-term PFS and survival data are awaited. Methods: BOLERO-2 is a phase 3, double-blind, randomized, international trial comparing EVE (10 mg once daily) + EXE (25 mg once daily) vs. placebo (PBO) + EXE in postmenopausal women with advanced estrogen-receptor–positive BC progressing or recurring after NSAIs (letrozole or anastrozole). Patients were randomized (2:1) to EVE + EXE or PBO + EXE. The primary endpoint was PFS by local investigator assessment. Main secondary endpoints included centrally assessed PFS, overall survival (OS), safety, bone turnover, and overall response rate. Results: Baseline disease characteristics including tumor burden and prior cancer therapy were well balanced between treatment arms (N = 724). Median PFS was doubled and response rates were consistently improved with EVE + EXE (n = 485) vs PBO + EXE (n = 239) in interim analyses. Median PFS by local assessment was ~3 mo with PBO + EXE vs 6.9 mo (hazard ratio [HR], 0.43; P < .0001) and 7.4 mo (HR, 0.44; P < .0001) with EVE + EXE at 7.5 mo and 12.5 mo follow-up, respectively. Fewer deaths were reported with EVE + EXE (17.2%) vs PBO + EXE (22.7%) at 12.5 mo follow-up. Safety profiles were consistent with previous reports for mTOR inhibitors. PFS data including 528 events (protocol-specified final analysis), and updated OS and safety data will be presented. Conclusions: Adding EVE to EXE markedly prolonged PFS in patients with NSAI-refractory advanced estrogen-receptor–positive BC. There were fewer deaths among patients receiving EVE, and further follow-up will evaluate the effect of EVE on OS.

Safety of everolimus for women over 65 years of age with advanced breast cancer (BC): 12.5-mo follow-up of BOLERO-2

551

Background: Postmenopausal women with estrogen-receptor–positive (ER+) BC who relapse/progress on a nonsteroidal aromatase inhibitor (NSAI) are usually treated with the steroidal AI exemestane (EXE); but there is no currently approved treatment for this indication. The BOLERO-2 trial showed that adding everolimus (EVE), an oral inhibitor of mammalian target of rapamycin (mTOR), to EXE significantly improved clinical benefit beyond that of EXE alone (Hortobagyi et al, SABCS 2011, Abstract S3-7). As many women with advanced BC are elderly, the tolerability profile of EVE + EXE in this population is of interest. Methods: BOLERO-2 is a phase III, randomized, trial comparing EVE (10 mg once daily) vs placebo (PBO), both plus EXE (25 mg once daily) in postmenopausal women with advanced ER+ BC progressing or recurring after NSAIs. Safety data with a focus on elderly patients are reported at 12.5 mo median follow-up. Results: Baseline disease characteristics, age, and prior cancer therapy were well balanced between treatment arms (N = 724). At 12.5 months’ median follow-up, the addition of EVE to EXE significantly improved progression-free survival in patients <65 (HR = 0.37; P < .05) or ≥65 years of age (HR = 0.56; P < .05). Adverse events (AEs) of special interest (all grades) occurring more frequently with EVE vs PBO (overall study population) included stomatitis (66.6% vs 11.3%), infections (50.4% vs 25.2%), rash (44.0% vs 8.4%), pneumonitis (18.7% vs 0.4%), and hyperglycemia (15.4% vs 2.5%). Elderly EVE-treated patients (≥65 years) had similar or marginally lower incidence of stomatitis (52.1%), rash (32.3%), pneumonitis (14.6%), and hyperglycemia (12.5%) compared with the overall population. Grade 3/4 AEs in patients ≥70 years of age (n = 161) reported only among patients receiving EVE (n = 118) included fatigue (10.2%), anemia (10.2%), hyperglycemia (8.5%), stomatitis (7.6%), dyspnea (6.8%), pneumonitis (5.1%), neutropenia (3.4%), and hypertension (3.4%). Conclusions: Adding EVE to EXE was well tolerated in the overall population and in elderly patients with advanced BC; grade 3/4 AEs were uncommon and manageable. Overall, AEs were consistent with the known safety profile of EVE.

Everolimus for postmenopausal women with advanced breast cancer: Updated results of the BOLERO-2 phase III trial

559

Background: Current treatment options for postmenopausal patients with estrogen-receptor–positive (ER+) breast cancer (BC) who relapse or progress on a nonsteroidal aromatase inhibitor (NSAI) are limited. The BOLERO-2 trial supports the activity of everolimus (EVE; an oral mammalian target of rapamycin [mTOR] inhibitor) added to the steroidal aromatase inhibitor exemestane (EXE) to prolong progression-free survival (PFS) in this patient population. Long-term PFS and survival data are awaited. Methods: BOLERO-2 is a phase III double-blind, randomized, international trial comparing EVE (10 mg once daily) plus EXE (25 mg once daily) versus placebo (PBO) plus EXE in postmenopausal women with advanced ER+ BC progressing or recurring after NSAIs (letrozole or anastrozole). Patients were randomized (2:1) to EVE + EXE or PBO + EXE. The primary endpoint was PFS by local investigator assessment. Main secondary endpoints included centrally assessed PFS, overall survival (OS), safety, bone turnover, and overall response rate (ORR). Results: Baseline disease characteristics including tumor burden and prior cancer therapy were well balanced between treatment arms (N = 724). Median PFS was doubled and response rates were consistently improved with EVE + EXE (n = 485) vs PBO + EXE (n = 239) in interim analyses. Median PFS by local assessment was ~3 mo with PBO + EXE vs 6.9 mo (hazard ratio [HR] = 0.43; P < .0001) and 7.4 mo (HR = 0.44; P < .0001) with EVE + EXE at 7.5 mo and 12.5 mo follow-up, respectively. Fewer deaths were reported with EVE + EXE (17.2%) vs PBO + EXE (22.7%) at 12.5 mo follow-up. Safety profiles were consistent with previous reports for mTOR inhibitors. PFS data including 528 events (protocol-specified final analysis), and updated OS and safety data will be presented. Conclusions: Adding EVE to EXE markedly prolonged PFS in patients with NSAI-refractory advanced ER+ BC. There were fewer deaths among patients receiving EVE, and further follow-up will evaluate the effect of EVE on OS.

BOLERO-1: A randomized, phase III, double-blind, placebo-controlled multicenter trial of everolimus in combination with trastuzumab and paclitaxel as first-line therapy in women with HER2-positive (HER2+), locally advanced or metastatic breast cancer (BC)

TPS648

Background: Up to 25% of BCs overexpress human epidermal growth factor receptor 2 (HER2). Patients with HER2+ disease have a higher rate of relapse and shorter overall survival (OS). Trastuzumab, a monoclonal antibody targeting HER2, is the standard of care and improves OS for HER2+ BC, but acquired resistance is common. The combination of trastuzumab and paclitaxel has shown good tolerability and excellent objective response rates (ORR) in up to 84% of patients with HER2+ metastatic BC (MBC) (Gasparini G, et al. BCRT. 2007;101:355-65). Everolimus is an orally bioavailable inhibitor of mammalian target of rapamycin (mTOR), a protein kinase central to multiple protein synthesis pathways and implicated in trastuzumab resistance. Everolimus-containing regimens have shown promising results in patients with ER+, HER2– advanced BC in phase II/III trials; everolimus plus trastuzumab/paclitaxel or vinorelbine has shown encouraging ORR with an acceptable safety profile in phase I/II trials in patients with HER2+ MBC. The present phase III study was undertaken to assess the effectiveness of adding everolimus to first-line standard therapy in HER2+ advanced BC. Methods: Women with HER2+, locally advanced or metastatic BC who have received no prior systemic therapy (except endocrine) are eligible. Local disease must not be amenable to resection with curative intent. Women with a history of central nervous system metastasis are excluded. Patients are randomized 2:1 (everolimus vs control) to receive standard therapy (paclitaxel and trastuzumab) plus everolimus (10 mg daily) or placebo. The primary endpoint is progression-free survival. Secondary endpoints include OS, ORR, and clinical benefit rate. Additional endpoints are safety, performance status, and biomarkers. This trial is sponsored by Novartis Pharmaceuticals and is registered (ClinicalTrials.gov: NCT00876395). Enrollment began September 2009, with a planned accrual of 717. The current accrual is 719, and the estimated primary completion date is October 2012.

Effects of everolimus (EVE) on disease progression in bone and bone markers (BM) in patients (pts) with bone metastases (mets)

512

Background: BOLERO-2, a multinational, double-blind, placebo-controlled, phase III study in postmenopausal women with estrogen-receptor–positive breast cancer (BC) refractory to non-steroidal aromatase inhibitors (NSAIs), showed significant clinical benefits with the addition of EVE to exemestane (EXE) (Baselga J, et al. NEJM. 2011 Epub). As bone resorption is an important factor in BC mets, it is interesting to study bone-related effects of EVE. In preclinical studies, mTOR inhibition was associated with decreased osteoclast survival and activity. Exploratory analyses in BOLERO-2 evaluated the effect of EVE vs placebo (PBO) on BM levels and BC progression in bone in pts with bone mets at baseline. Methods: Eligible pts were treated with EXE (25 mg once daily) and randomized (2:1) to EVE (10 mg once daily) or PBO. Bone turnover markers were exploratory endpoints analyzed at 6 and 12 wks after treatment initiation, and included bone-specific alkaline phosphatase, amino-terminal propeptide of type I collagen, and C-terminal cross-linking telopeptide of type I collagen. Progressive disease in bone (PDB) was defined as worsening of a pre-existing bone lesion or a new bone lesion. Results: Baseline disease characteristics, including bone mets at baseline (n = 370, 76% EVE vs n = 184, 77% PBO), were well balanced between arms (N = 724), and baseline bisphosphonate use was not (44% EVE vs 55% PBO). At 12.5 mo median follow-up, progression-free survival (primary endpoint), overall response rate, and clinical benefit rate (P < .0001, all) were significantly higher with EVE (n = 485) vs PBO (n = 239). BM levels at 6 and 12 wks increased vs baseline with PBO, but decreased with EVE. The cumulative incidence rate of BC PBD was lower for EVE vs PBO at day 60 (3.03% vs 6.16%, respectively) and this trend was sustained beyond 6 months. Updated results will be presented. All bone-related adverse events reported were grade1/2 and occurred with similar frequency in EVE- (2.9%) and PBO- (3.8%) treated patients. Conclusions: Exploratory analyses from BOLERO-2 suggest that adding EVE has beneficial effects on bone turnover and BC progression in bone in pts receiving EXE therapy for NSAI-refractory BC.

Analysis of Bevacizumab (Bev) Therapy, Bisphosphonate Use and Osteonecrosis of the Jaw (ONJ) in &gt;1900 Patients Treated in Two Randomized, Controlled Trials

Background: Long-term bisphosphonate therapy is known to increase the risk of ONJ. A 16% incidence of ONJ was reported in a retrospective analysis of 116 patients receiving bisphosphonates with anti-angiogenic therapy (Bev or sunitinib) for bone metastases from breast, colon, or renal cell cancers.Methods: To assess the incidence of ONJ with Bev, we analyzed data from &gt;3500 patients with locally recurrent or metastatic breast cancer (LR/MBC) treated in three large trials of Bev-containing therapy: AVADO (Bev in combination with docetaxel); RIBBON-1 (Bev in combination with taxane, anthracycline-based combination therapy, or capecitabine); and MO19391 (single-arm safety study of &gt;2000 patients receiving Bev-containing therapy in the general oncology practice context). The incidence of ONJ was compared in patients treated with Bev versus placebo and in patients with or without bisphosphonate exposure.Results: Data from the blinded phase of two randomized, placebo-controlled trials demonstrated an ONJ incidence of 0.3%. ONJ was more common in patients who also received bisphosphonate therapy than in those who received no bisphosphonates (Table). This observation is supported by data from 2216 patients treated in the single-arm MO19391 study (2.4% with bisphosphonate versus 0% without). AVADO*RIBBON-1**TotalIncidence of ONJ, no. of pts (%)Bev (n=492)Pla (n=238)Bev (n=817)Pla (n=412)Bev (n=1309)Pla (n=650)Overall population receiving Bev (n=1309)3 (0.6%)O1 (0.1%)O4 (0.3%)OBisphosphonate (n=233)1 (1.2%)O1 (0.6%)O2 (0.9%)ONo bisphosphonate (n=1076)2 (0.5%)OOO2 (0.2%)O *Bev 15 and 7.5 mg/kg arms pooled**Taxane/anthracycline and capecitabine cohorts pooledConclusions: This is the largest analysis of ONJ in patients receiving Bev for LR/MBC. The 0.3% incidence of ONJ with Bev is considerably lower than previously reported by Christodoulou et al. with anti-angiogenic therapy. As in the general population, the risk of ONJ is increased in patients exposed to bisphosphonates. The 0.9–2.4% incidence seen here in a large population of patients receiving Bev and bisphosphonate therapy is substantially lower than the 16% observed in a small cohort of patients from a retrospective analysis and within the range reported in the literature for bisphosphonates alone (1–4%). Good oral hygiene, dental examination and avoidance of invasive dental procedures remain important in patients receiving bisphosphonates, irrespective of Bev treatment.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 208.