Abstract PD5-07: A phase III randomized trial of anastrozole and fulvestrant versus anastrozole or sequential anastrozole and fulvestrant as first-line therapy for postmenopausal women with metastatic breast cancer: Final survival outcomes of SWOG S0226

Background: Anastrozole depletes estrogen via aromatase inhibition and fulvestrant binds and degrades estrogen receptor. In a Phase III trial we compared the concurrent use of these agents to anastrozole alone or sequential anastrozole and fulvestrant in first-line therapy of hormone receptor-positive metastatic breast cancer in postmenopausal women, and demonstrated improved progression-free (PFS) and overall survival (OS)-NEJM 2012. Now we report PFS and OS five years after the initial positive findings. Methods: A total of 707 patients were randomized to either 1 mg anastrozole P.O. daily (Arm 1) or to the combination of anastrozole and fulvestrant (Arm 2). Fulvestrant was administered as a loading dose of 500 mg on day 1, 250 mg on days 14, 28 and monthly thereafter. Randomization was stratified by adjuvant tamoxifen use. The primary endpoint was PFS with OS a secondary outcome. 40% patients not in visceral crisis crossed over to fulvestrant after progression on arm 1. Analysis of survival was by 2-sided stratified log-rank tests and Cox regression using intent-to-treat. Subset analyses include treatment effect by adjuvant tamoxifen exposure, initial sites of metastases and time from diagnosis. Results: There were 646 PFS events (328 and 318 for arms 1 and 2, respectively) among 694 eligible patients (345 and 349, respectively). Overall, median PFS was 13.5 months for arm 1 and 15.0 months for the arm 2 (log-rank p=0.007; HR=0.81 (95% CI 0.69-0.94)). This benefit extended similarly in visceral and non-visceral subgroups. In subset analysis for Arms 1 and 2, respectively, in tamoxifen-naive women (60%, n=414), median PFS was 12.7 vs. 16.7 months (log-rank p=0.002; HR=0.73 (95% CI 0.60-0.89) while in women exposed to tamoxifen, median PFS was 13.9 vs. 13.6 months (log-rank p=0.57; HR=0.93 (95% CI 0.73-1.19)). An improved OS in the combination arm was seen, median OS 42 and 50 months in arms 1 and 2, based on 261 and 247 deaths, respectively (log-rank p=0.028; HR=0.82 (95% CI 0.69-0.98)). In subset analysis in tamoxifen-naive women, median OS was 40.3 vs. 52.2 months for Arms 1 and 2, respectively (log-rank p=0.007; HR=0.73 (95% CI 0.58-0.92)) while in women exposed to tamoxifen, median OS was 43.5 vs. 48.2 months (log-rank p=0.85; HR=0.97 (95% CI 0.74-1.27). Patients with initial diagnosis >10 years benefitted most from the combination (HR=0.66 (95% CI 0.49-0.89)) regardless of tamoxifen exposure. Patients in Arm 1 who crossed over had post-progression survival similar to post-progression survival of Arm 2 patients. Conclusion: The addition of fulvestrant to anastrozole was associated with improved long-term PFS and OS compared to anastrozole alone, despite the use of fulvestrant at a dose lower than the approved, and despite the substantial cross over to fulvestrant after progression on anastrozole alone. The benefit was especially notable in those without recent exposure to adjuvant endocrine therapy. Ongoing translational medicine studies will further refine the need for up front fulvestrant. ClinicalTrials.gov:NCT00075764. Funding: NIH/NCI U10CA180888, U10CA180819 and AstraZeneca.

Citation Format: Mehta RS, Barlow WE, Albain KS, Vandenberg TA, Dakhil SR, Tirumali NL, Lew DL, Hayes DF, Gralow JR, Linden HM, Livingston RB, Hortobagyi GN. A phase III randomized trial of anastrozole and fulvestrant versus anastrozole or sequential anastrozole and fulvestrant as first-line therapy for postmenopausal women with metastatic breast cancer: Final survival outcomes of SWOG S0226 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-07.

Abstract P1-15-01: Final analysis of SWOG S0230/Prevention of early menopause study (POEMS)

BACKGROUND: The SWOG S0230/POEMS study demonstrated a 70% reduction in ovarian failure (OF) with goserelin coadministration during chemotherapy (CT) for ER-negative early breast cancer (BC; Moore H et al, NEJM 2015). Goserelin use was also associated with more pregnancies as well as favorable disease free survival (DFS) and overall survival (OS). Here we report the final analysis after 5 years of follow-up.

METHODS: Premenopausal women age <50 with stage I-IIIA ER/PR-negative BC to be treated with cyclophosphamide-containing CT were randomized to receive standard CT with or without monthly goserelin 3.6 mg SQ starting at least 1 week prior to the first CT dose. The primary endpoint was OF at 2-years, defined as amenorrhea for the prior 6 months and post-menopausal FSH. Secondary endpoints included pregnancies, disease free survival (DFS) and overall survival (OS). An unplanned analysis of rate of menses recovery at 2 years (presence of menses within 6 months of the 2 year time-point or pregnancy within the first 2 years) was also conducted. OF and pregnancy endpoints were analyzed using multivariable logistic regression adjusting for stratification factors (age and CT regimen); DFS and OS were examined using multivariable Cox regression, adjusting for stratification factors and stage. Two-sided p-values are reported unless otherwise specified in accordance with protocol design.

RESULTS: Among 257 randomized participants, 218 were eligible and evaluable. One hundred thirty-six eligible and evaluable patients had OF data and 186 had menstrual data. Median age was 37.7 years. Among the 136 patients with OF data, the odds ratio (OR) for OF at 2 years was 0.30 (95% CI 0.1-0.98; one-sided p=0.023) comparing CT with goserelin to standard CT alone. Among 186 patients with menstrual data, 80% recovered menses by 2 years in the goserelin arm compared with 70% in the standard arm (OR=1.74, 95% CI: 0.83-3.66, p=0.15). Pregnancies, DFS and OS are reported for all 218 eligible and evaluable patients. With a median follow-up of 5.1 years, 22% of patients in the goserelin group had at least one pregnancy compared with 12% in the standard group (OR 2.38, 95% CI 1.08-5.26, p=0.03). Cumulative incidence of pregnancy at 5 years is 23% in the goserelin arm compared with 12% in the standard group. Five-year Kaplan-Meier DFS estimates are 88% in the goserelin arm compared with 79% in the standard arm (HR=0.50, p=0.05). Five-year OS is 92% with goserelin versus 83% in the standard arm (HR=0.47, p=0.06). Including all 257 randomized patients, HR for DFS and OS are 0.67 and 0.48 (p=0.18 and p=0.05).

CONCLUSION: Ovarian suppression with goserelin during chemotherapy for hormone receptor-negative breast cancer reduces OF risk and, after 5 years of follow-up, continues to be associated with more pregnancies and improved survival compared with chemotherapy without goserelin.

SUPPORT: NIH/NCI grant awards CA189974, CA180888, CA180819, CA074362; AstraZeneca

Citation Format: Moore HCF, Unger JM, Phillips K-A, Boyle F, Hitre E, Moseley A, Porter D, Francis PA, Goldstein LJ, Gomez HL, Vallejos CS, Partridge AH, Dakhil SR, Garcia AA, Gralow J, Lombard JM, Forbes JF, Martino S, Barlow WE, Fabian CJ, Minasian L, Meyskens FL, Gelber RD, Hortobagyi GN, Albain KS. Final analysis of SWOG S0230/Prevention of early menopause study (POEMS) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-15-01.

Continued Treatment Effect of Zoledronic Acid Dosing Every 12 vs 4 Weeks in Women With Breast Cancer Metastatic to Bone: The OPTIMIZE-2 Randomized Clinical Trial

Importance

Zoledronic acid, a potent bisphosphonate, is commonly administered to patients with bone metastases to reduce the risk of skeletal-related events (SREs). However, there have been concerns regarding its long-term monthly administration.

Objective

To examine whether zoledronic acid every 12 weeks was noninferior to zoledronic acid every 4 weeks in patients with metastatic breast cancer that involved the bone who had previously received a standard dosing regimen of zoledronic acid and/or pamidronate disodium.

Design, Setting, and Participants

OPTIMIZE-2 was a prospective, randomized, double-blind, multicenter phase 3 trial of intention-to-treat (full analysis set), evaluable (per protocol), and safety populations. Patients were randomized (1:1) to receive 4.0 mg of intravenous zoledronic acid every 4 or every 12 weeks with placebo for interim infusions for 1 year. The study was conducted at 102 clinical trial centers in the United States from March 3, 2006, to July 25, 2013. Data analysis was performed from October 7, 2013, to March 24, 2014. The study randomized 416 women (≥18 years old) with bone metastases from breast cancer who previously received 9 or more doses of zoledronic acid and/or pamidronate during the first 10 to 15 months of therapy.

Main Outcomes and Measures

The primary end point was the proportion of patients with 1 or more SRE on study (SRE rate). The key secondary end points included time to first SRE and skeletal morbidity rate (SMR).

Results

A total of 416 women were randomized: 200 patients received zoledronic acid every 4 weeks (mean [SD] age, 59.2 [11.1] years; 173 were white [86.5%]), 203 patients received zoledronic acid every 12 weeks (mean [SD] age, 58.6 [11.2] years; 178 were white [87.7%]), and 13 patients received placebo (mean [SD] age, 60.8 [12.2] years; 13 were white [100%]). Baseline characteristics were similar in both zoledronic acid treatment arms. After 1 year of follow-up, SREs occurred in 44 patients (22.0%) in the zoledronic acid every 4 weeks group and 47 patients (23.2%) in the zoledronic acid every 12 weeks group (proportional difference of -1.2%; 1-sided 97.5% CI bound of the difference in SRE rate between arms, -9.8%; noninferiority P = .02). The time to first SRE between treatment groups was not statistically significantly different (hazard ratio [HR], 1.06; 95% CI, 0.70-1.60; P = .79). The mean (SD) SMR was 0.46 (1.06) vs 0.50 (1.50) events per year in the every 4 weeks vs every 12 weeks groups (P = .85). The safety profiles of the every 4 weeks and every 12 weeks groups were comparable, with 189 patients (95.5%) in the every 4 weeks group having at least 1 adverse event compared with 189 (93.5%) in the every 12 weeks group.

Conclusions and Relevance

The every 12 weeks regimen of zoledronic acid was noninferior to the every 4 weeks regimen for the proportion of patients experiencing 1 or more SRE. These results may have a substantial influence on current clinical practice for treatment of patients with bone metastasis from breast cancer.

Trial Registration

clinicaltrials.gov Identifier: NCT00320710.

B-F1RST: Assessment of novel blood-based biomarkers in patients with first-line advanced or metastatic NSCLC receiving atezolizumab monotherapy

TPS9103

Background: The anti–PD-L1 monoclonal antibody atezolizumab inhibits the interaction of PD-L1 with its receptors PD-1 and B7.1, thereby restoring T-cell immunity. In the Phase III OAK study, patients with previously treated advanced NSCLC had improved mOS in the atezolizumab arm (13.8 mo) vs the docetaxel arm (9.6 mo) (HR 0.73 [95%CI: 0.62, 0.87]; P= 0.0003), irrespective of PD-L1 expression or histology. A Phase III clinical trial of atezolizumab monotherapy for first-line, PD-L1–selected patients with NSCLC is underway; however, first-line atezolizumab monotherapy for NSCLC treatment in a biomarker-unselected population has not yet been investigated. Current assays to measure PD-L1 expression by IHC require tumor biopsies, which can be difficult to obtain in some patients. Novel blood-based biomarkers will be evaluated retrospectively in B-F1RST (Blood-First-Line Ready Screening Trial) in patients receiving atezolizumab monotherapy in first-line NSCLC. Methods: A Phase II, open-label, single-arm study, B-F1RST (NCT02848651), will evaluate the efficacy and safety of atezolizumab in PD-L1–unselected patients with first-line locally advanced or metastatic NSCLC. Eligibility criteria include stage IIIB-IVB NSCLC, ECOG PS 0-1, measurable disease per RECIST v1.1 and adequate hematologic and end-organ function. Exclusion criteria include the presence of EGFRmutations or ALKfusions, active CNS metastases and prior immunotherapy for NSCLC. Patients will receive atezolizumab 1200 mg IV q3w until disease progression or loss of clinical benefit. Prospective collection of blood samples is mandatory; collection of tissue biopsies is optional. The co-primary endpoints of the study are investigator-assessed ORR per RECIST v1.1 for the efficacy objective and PFS per RECIST v1.1 for evaluating blood-based predictive biomarkers for atezolizumab efficacy, including mutation status. Approximately 150 patients will be enrolled at 25 or more centers in the United States. Clinical trial information: NCT02848651.

Longitudinal assessment of cancer-related cognitive impairment (CRCI) up to six-months post-chemotherapy with multiple cognitive testing methods in 943 breast cancer (BC) patients and controls

10014

Background: Large nationwide studies are needed to assess CRCI. Methods: NCORPs recruited BC patients and age-matched non-cancer controls. Computerized ((CANTAB Delayed Match to Sample (DMS), Rapid Visual Processing (RVP), Verbal Recognition Memory (VRM)), paper-based ((Controlled Oral Word Association (COWA), and Trail Making Test (TMT)) , and phone-based (category fluency, word recall, backward counting and digits backward) cognitive assessments of memory, attention, and executive function at pre-chemotherapy, post-chemotherapy, and 6 months follow-up (or time-equivalent for controls) were completed. Longitudinal mixed model (LMM)s included group, time, time*group, and adjusted for age, education, reading, anxiety, and depression. Results: 580 BC patients (mean age = 54) and 363 controls (mean age = 53) were assessed. In all LMMs, there was a significant group*time interaction depicting lower scores in patients compared to controls (p < 0.005) except for TMT (p = 0.09). For longitudinal change on the DMS memory test (primary aim), we observed no significant difference between groups from pre- to post-chemotherapy but did observe a significant difference from pre-chemotherapy to follow-up (p = 0.017) where patients significantly declined (p = 0.005) and controls did not change. We observed similar results for RVP. For VRM, there was a significant pre- to post-chemotherapy group difference (p = 0.003). For COWA, patients significantly declined and controls significantly improved reflecting a significant between group difference (p < 0.001) from pre- to post-chemotherapy. For TMT, both groups significantly improved with patients improving less than controls reflected by a significant between group difference (p = 0.04) that remained a trend at follow-up (p = 0.06). On all phone tests, there was a significant between group effect from both pre- to post-chemotherapy and at follow-up with patients doing less well than controls (all p < 0.001). Conclusions: This nationwide study shows CRCI in BC patients persists in multiple cognitive domains up to 6 months post-chemotherapy compared to controls. Clinical trial information: NCT01382082.

Relationship between smoking, prognostic factors, and outcomes in patient (pts) with metastatic castration-resistant prostate cancer (mCRPC) receiving sipuleucel-T (sip-T): Preliminary analysis of the PROCEED registry

216

Background: Smoking is associated with poor treatment outcomes after definitive therapy for PC (Steinberger 2015 BJU Int; Joshu 2011 JNCI). However, there is a paucity of data on the effects of active smoking on pts with mCRPC. The PROCEED registry provides an opportunity to evaluate differences in disease characteristics and outcomes by smoking status in men receiving sip-T, an FDA-approved, autologous cellular immunotherapy for asymptomatic or minimally symptomatic mCRPC. Methods: Enrolled pts with mCRPC who never smoked (NS) or were current smokers (CS) were evaluated.Pt characteristics, time to first anticancer intervention (tACI; measured from last sip-T infusion to first ACI; agents: abiraterone, enzalutamide, docetaxel, cabazitaxel, radium-223), PC-specific survival, and OS were assessed. Results: Of 1956 enrolled pts with known smoking status, 904 were NS, 179 were CS; 873 were former smokers and not included in this analysis. Compared with NS, CS were younger, had lower BMI (p < 0.001), higher hemoglobin (Hgb; p < 0.001), lower lactate dehydrogenase (LDH; p = 0.05), and shorter time between PC diagnosis and first sip-T infusion (p = 0.01). Fewer CS pts had Gleason score < 8 (p = 0.2) and prior radical prostatectomy (p = 0.07). CS and NS did not differ in pattern or extent of metastatic disease spread. CS was associated with shorter OS, PC-specific survival, and tACI (Table). Conclusions: CS were younger at enrollment and had shorter OS, PC-specific survival, and tACI. Higher Hgb in CS likely reflects reduced plasma volume and/or increased red cell production. A multivariate analysis of prognostic factors for survival outcomes including smoking status in mCRPC is planned. However, active smoking represents a possible modifiable risk factor in the mCRPC setting. Clinical trial information: NCT01306890. [Table: see text]

Phase III Randomized Study of 4 Weeks of High-Dose Interferon-α-2b in Stage T2bNO, T3a-bNO, T4a-bNO, and T1-4N1a-2a (microscopic) Melanoma: A Trial of the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Cancer Research Group (E1697)

Purpose To test the efficacy of 4 weeks of intravenous (IV) induction with high-dose interferon (IFN) as part of the Eastern Cooperative Oncology Group regimen compared with observation (OBS) in patients with surgically resected intermediate-risk melanoma. Patients and Methods In this intergroup international trial, eligible patients had surgically resected cutaneous melanoma in the following categories: (1) T2bN0, (2) T3a-bN0, (3) T4a-bN0, and (4) T1-4N1a-2a (microscopic). Patients were randomly assigned to receive IFN α-2b at 20 MU/m²/d IV for 5 days (Monday to Friday) every week for 4 weeks (IFN) or OBS. Stratification factors were pathologic lymph node status, lymph node staging procedure, Breslow depth, ulceration of the primary lesion, and disease stage. The primary end point was relapse-free survival. Secondary end points included overall survival, toxicity, and quality of life. Results A total of 1,150 patients were randomly assigned. At a median follow-up of 7 years, the 5-year relapse-free survival rate was 0.70 (95% CI, 0.66 to 0.74) for OBS and 0.70, (95% CI, 0.66 to 0.74) for IFN ( P = .964). The 5-year overall survival rate was 0.83 (95% CI, 0.79 to 0.86) for OBS and 0.83 (95% CI, 0.80 to 0.86) for IFN ( P = .558). Treatment-related grade 3 and higher toxicity was 4.6% versus 57.9% for OBS and IFN, respectively ( P < .001). Quality of life was worse for the treated group. Conclusion Four weeks of IV induction as part of the Eastern Cooperative Oncology Group high-dose IFN regimen is not better than OBS alone for patients with intermediate-risk melanoma as defined in this trial.

Fulvestrant decreases anastrozole drug concentrations when taken concurrently by patients with metastatic breast cancer treated on SWOG study S0226

AIMS

In the SWOG S0226 trial the combination of anastrozole plus fulvestrant (n = 349) was superior to anastrozole alone (n = 345) in hormone receptor (HR)-positive metastatic breast cancer. Here we report a pharmacokinetic subset analysis investigating a possible drug interaction between anastrozole and fulvestrant.

METHODS

Post-menopausal patients with HR-positive metastatic breast cancer were randomized to anastrozole with or without concurrent fulvestrant. Blood samples were collected at 2, 4, 6 and 8 months, just prior to receiving the next dose of anastrozole and fulvestrant. Drug concentrations were measured via LC/MS-MS. Anastrozole concentration was compared in patients on anastrozole alone vs. patients on concomitant fulvestrant. Comparisons were made at each time point using parametric tests and over time using a linear mixed effects model.

RESULTS

A total of 483 anastrozole concentration measurements were included, 224 samples from 64 patients on the anastrozole alone arm and 259 from 73 patients on the combination arm. The mean anastrozole concentration in the combination arm was significantly lower than that in the anastrozole alone arm at each sample collection time (all P < 0.01) and in the mixed effects model (an estimated difference of 9.85 ng ml(-1) (95% CI 5.69, 14.00 ng ml(-1) ), P < 0.001).

CONCLUSION

A significant pharmacokinetic drug interaction was detected, in which the addition of fulvestrant to anastrozole treatment decreased the trough anastrozole concentration. Further research is needed to verify whether this interaction affects treatment efficacy and to determine the pharmacological mechanism by which this interaction occurs.

Abstract P3-07-64: Association between gene variants in SULT1A1 and UGT1A4 and disease outcomes in patients enrolled in SWOG S0226 and treated with anastrozole alone or in combination with fulvestrant for metastatic breast cancer

Background: Anastrozole (A) blocks estrogen production by inhibiting the activity of CYP19 aromatase. Fulvestrant (F) blocks estrogen receptor (ER) signaling by competitive binding, leading to ER degradation by ubiquitination. SWOG S0226 ("Phase III Randomized Trial of Anastrozole versus Anastrozole and Fulvestrant (250mg LD) as First Line Therapy for Post Menopausal Women with Metastatic Breast Cancer," ClinicalTrials.gov Identifier:NCT00075764) demonstrated that combination of A+F is superior to A alone as first-line therapy for patients with ER positive metastatic breast cancer (Mehta et al, NEJM, 2012). Our functional preclinical studies have shown that single nucleotide polymorphisms (SNPs) in SULT1A1 and UGT1A4, drug conjugation enzymes that inactivate A and F, result in decreased enzyme activity toward these drugs (Edavana et al, DMD, 2013; Edavana et al Pharmgenomics Pers Med 2013). We therefore hypothesized that these SNPs will be associated with disease outcomes in S0226 patients due to altered drug levels.

Methods: Germline DNA was available for 295 (43.5%) patients enrolled in S0226 overall (157 on A and 138 on A+F). SNPs in SULT1A1 and UGT1A4 were determined either by direct sequencing or allele-specific PCR (TaqMan) assays.

Results: There was no difference in progression-free survival (PFS) or overall survival (OS) comparing patients with or without available germline DNA (p = 0.86 and 0.36, respectively). The SULT1A1 G902A allele (rs6839), which confers decreased mRNA and enzymatic activity, was associated with improved PFS (GG/GA vs. AA; HR 0.74, 95% CI 0.56-0.98, p=0.033) and OS (HR 0.70, 95% 0.50-0.98, p=0.039). In exploratory subset analyses of PFS, the SULT1A1 G902A association was similar across both treatment arms (A HR=0.75; 95% CI 0.51-1.10; A+F HR=0.73; 95% CI 0.48-1.11). For OS there was some evidence of a difference by treatment (A HR=0.60; 95% CI 0.38-0.96; A+F HR=0.82; 95% CI 0.50-1.32), though no significant interaction was evident (p=0.30).

The UGT1A4 G-163A promoter variant, which leads to decreased protein expression, was not associated with PFS (AA/AG vs. GG HR 0.88, 95% CI 0.68-1.14, p=0.33); however, this variant was associated with OS (HR 0.71, 95% CI 0.52-0.96, p=0.027). In subset analyses with OS, the difference was marginally stronger in the A arm (HR 0.63, 95% CI 0.42-0.97, p=0.035) compared to the A+F arm (HR 0.77, 95% CI 0.49-1.21, p=0.25), though the interaction was not significant (p=0.40).

Conclusion: SULT1A1 and UGT1A4 gene variants resulting in decreased enzyme activity were associated with better PFS, OS or both in patients enrolled in SWOG S0226. Planned validation studies correlating these SNPs with drug levels and disease outcomes in additional patient cohorts will establish their clinical utility in identifying patients who benefit from A and F alone or in combination.

Funding: Supported by NIH/NCI CA118981; NIH/NCI/NCTN grants CA180888, CA180819, and CA180863; and in part by AstraZeneca.

Citation Format: Kadlubar SA, Barlow WE, Mehta RS, Daniels JR, Albain KS, Vandengerg TA, Dakhil SR, Tirumali NR, Lew DL, Gralow JR, Livingston RB, Hortobagiyi GN, Hayes DF, Rae JM. Association between gene variants in SULT1A1 and UGT1A4 and disease outcomes in patients enrolled in SWOG S0226 and treated with anastrozole alone or in combination with fulvestrant for metastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-64.

Real-world experience of therapeutic sequencing and time to first anticancer intervention (ACI) following sipuleucel-T (sip-T): Initial data from the PROCEED registry

194

Background: Sip-T is an autologous immunotherapy approved for asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC).Many therapeutic agents have been approved in a short time frame, and their optimal sequencing in mCRPC is under investigation. The sequencing of agents post–sip-T treatment on PROCEED (NCT01306890) and factors associated with a shorter time to first ACI (tACI) are described. Methods: The number of unique and most common sequences and sequence trends were analyzed. Post–sip-T ACIs evaluated were abiraterone (abi), enzalutamide (enz), docetaxel (D), and cabazitaxel (cbz), excluding radium-223 due to its late approval relative to PROCEED initiation. The tACI and factors associated with shorter tACI were assessed. Results: 1902 pts received ≥1 sip-T infusion, and an estimated 37.0% and 21.2%had not received an ACI at 1 and 2 y, respectively, post–sip-T. 1331 (70%) pts received abi, enz, D, or cbz after sip-T. 47 therapy sequences were recorded post–sip-T, with the most used therapies in order of prevalence: abi alone, enz alone, D alone, abi → enz, abi → D, D → enz, and D → abi. The most common post–sip-T sequences beginning with abi, enz, or D are below (Table). Only 25 pts received cbz as the first ACI post–sip-T. Pts who received abi prior to sip-T had a shorter median tACI (4.6 mos) compared with all pts (8.3 mos) or pts with D prior to sip-T (7.3 mos). Higher baseline alkaline phosphatase, lower hemoglobin, and prior radical prostatectomy were associated with shorter tACI. Conclusions: In the evolving mCRPC space, 47 unique ACI sequences were recorded post-sip-T. The most common sequences post–sip-T were abi, enz, and D as single agents. Prior abi was associated with a shorter tACI post–sip-T, which warrants longer follow-up. While many pts received subsequent therapy, ~20% had not received an ACI at 2 y post–sip-T. Clinical trial information: NCT01306890. [Table: see text]

A randomized comparison of once weekly epoetin alfa to extended schedule epoetin or darbepoetin in chemotherapy-associated anemia

Erythropoiesis-stimulating agents (ESAs) epoetin alfa (EA) and darbepoetin alfa (DA) increase hemoglobin (Hb) levels and reduce red blood cell (RBC) transfusion requirements in patients with cancer chemotherapy-associated anemia (CAA). Extended-interval ESA dosing (administration less than once weekly) is common with DA, but previous studies suggested that EA might also be administered less often than weekly. In this multicenter prospective trial, 239 CAA patients with Hb <10.5 g/dL were randomized to receive EA 40,000 U subcutaneously once weekly ("40K" arm), EA 80,000 U every 3 weeks ("80K"), EA 120,000 U every 3 weeks ("120K" arm), or DA 500 mcg every 3 weeks ("DA"), for 15 weeks. The primary endpoint was the proportion of patients achieving Hb ≥ 11.5 g/dL or increment of Hb > 2.0 g/dL from baseline without transfusion. Secondary endpoints included transfusion requirements, adverse events (AEs), and patient-reported outcomes (PROs). There were no significant differences between treatment arms in the proportion of patients achieving Hb response (68.9% for 40K, 61.7% for 80K, 65.5% for 120K, and 66.7% for DA; P > 0.41 for all comparisons) or requiring RBC transfusion, but the median Hb increment from baseline was higher in the 40K and DA arms compared to the two extended dosing EA arms, and Hb response was achieved soonest in the weekly EA arm. There were no differences in PROs or AEs. The FDA-approved schedules tested-weekly EA 40,000 U, and every 3 week DA 500 mcg-are reasonable standards for CAA therapy.

Phase III study of APF530 versus ondansetron with a neurokinin 1 antagonist + corticosteroid in preventing highly emetogenic chemotherapy-induced nausea and vomiting: MAGIC trial

68

Background: Managing chemotherapy-induced nausea and vomiting (CINV) associated with delayed ( > 24-120 h) highly emetogenic chemotherapy (HEC) is an unmet need. APF530, extended-release granisetron, provides sustained release over ≥ 5 days to prevent acute (0-24 h) and delayed CINV. This trial compared the efficacy and safety of APF530 in preventing CINV after HEC in a 3-drug regimen vs a standard 3-drug regimen with ondansetron (Ond). Methods: In this double-blind, multicenter study (NCT02106494), patients (pts) receiving single-day HEC (2011 ASCO guidelines) were randomized 1:1 to APF530 500 mg SC (10 mg granisetron) or Ond 0.15 mg/kg IV and stratified by cisplatin ( ≥ 50 mg/m2, yes/no). Pts were scheduled to receive concomitant dexamethasone (Dex) 12 mg IV + fosaprepitant (Fos) 150 mg IV on day 1 + PO Dex on days 2-4. The primary end point was delayed-phase complete response (CR) (no emesis, no rescue medication). Secondary end points included CR in acute and overall phases and complete control (CC; CR and no more than mild nausea) in acute, delayed, and overall phases. Treatment (tx) comparisons used chi-square test controlling for cisplatin. Adverse events (AEs) and injection-site reactions (ISRs) were assessed. Results: Modified intent-to-treat analysis included 902 pts (APF530, n = 450; Ond, n = 452) with baseline demographics balanced between tx groups. A significantly higher % of APF530 (65%) vs Ond (57%) pts had delayed-phase CR (P= .014). A significantly higher % of APF530 (61%) vs Ond (53%) pts had delayed-phase CC (P= .022, Table). CR and CC rates in acute and overall phases were numerically higher with APF530 vs Ond, but not statistically significant. APF530 was well tolerated. Most common AEs were ISRs, mostly mild or moderate. Conclusions: APF530 with Fos+Dex led to statistically higher CR and CC rates in delayed-phase CINV with HEC vs a standard 3-drug regimen of Ond with Fos+Dex. Clinical trial information: NCT02106494. [Table: see text]

Randomized Multicenter Placebo-Controlled Trial of Omega-3 Fatty Acids for the Control of Aromatase Inhibitor-Induced Musculoskeletal Pain: SWOG S0927

PURPOSE

Musculoskeletal symptoms are the most common adverse effects of aromatase inhibitors (AIs) and can result in decreased quality of life and discontinuation of therapy. Omega-3 fatty acids (O3-FAs) can be effective in decreasing arthralgia resulting from rheumatologic conditions and reducing serum triglycerides.

PATIENTS AND METHODS

Women with early-stage breast cancer receiving an AI who had a worst joint pain/stiffness score ≥ 5 of 10 using the Brief Pain Inventory-Short Form (BPI-SF) were randomly assigned to receive either O3-FAs 3.3 g or placebo (soybean/corn oil) daily for 24 weeks. Clinically significant change was defined as ≥ 2-point drop from baseline. Patients also completed quality-of-life (Functional Assessment of Cancer Therapy-Endocrine Symptoms) and additional pain/stiffness assessments at baseline and weeks 6, 12, and 24. Serial fasting blood was collected for lipid analysis.

RESULTS

Among 262 patients registered, 249 were evaluable, with 122 women in the O3-FA arm and 127 in the placebo arm. Compared with baseline, the mean observed BPI-SF score decreased by 1.74 points at 12 weeks and 2.22 points at 24 weeks with O3-FAs and by 1.49 and 1.81 points, respectively, with placebo. In a linear regression adjusting for the baseline score, osteoarthritis, and taxane use, adjusted 12-week BPI-SF scores did not differ by arm (P = .58). Triglyceride levels decreased in patients receiving O3-FA treatment and remained the same for those receiving placebo (P = .01). No between-group differences were seen for HDL, LDL, or C-reactive protein.

CONCLUSION

We found a substantial (> 50%) and sustained improvement in AI arthralgia for both O3-FAs and placebo but found no meaningful difference between the groups.

5-year follow-up of a randomized controlled trial of immediate versus delayed zoledronic acid for the prevention of bone loss in postmenopausal women with breast cancer starting letrozole after tamoxifen: N03CC (Alliance) trial

BACKGROUND

Postmenopausal women with breast cancer receiving aromatase inhibitors are at an increased risk of bone loss. The current study was undertaken to determine whether upfront versus delayed treatment with zoledronic acid (ZA) impacted bone loss. This report described the 5-year follow-up results.

METHODS

A total of 551 postmenopausal women with breast cancer who completed tamoxifen treatment and were undergoing daily letrozole treatment were randomized to either upfront (274 patients) or delayed (277 patients) ZA at a dose of 4 mg intravenously every 6 months. In the patients on the delayed treatment arm, ZA was initiated for a postbaseline bone mineral density T-score of <-2.0 or fracture.

RESULTS

The incidence of a 5% decrease in the total lumbar spine bone mineral density at 5 years was 10.2% in the upfront treatment arm versus 41.2% in the delayed treatment arm (P<.0001). A total of 41 patients in the delayed treatment arm were eventually started on ZA. With the exception of increased NCI Common Toxicity Criteria (CTC) grade 1/2 elevated creatinine and fever in the patients treated on the upfront arm and cerebrovascular ischemia among those in the delayed treatment arm, there were no significant differences observed between arms with respect to the most common adverse events of arthralgia and back pain. Osteoporosis occurred less frequently in the upfront treatment arm (2 vs 8 cumulative cases), although this difference was not found to be statistically significant. Bone fractures occurred in 24 patients in the upfront treatment arm versus 25 patients in the delayed treatment arm.

CONCLUSIONS

Immediate treatment with ZA prevented bone loss compared with delayed treatment in postmenopausal women receiving letrozole and these differences were maintained at 5 years. The incidence of osteoporosis or fractures was not found to be significantly different between treatment arms.