Caroline Wilson

Adjuvant zoledronic acid in patients with early breast cancer: final efficacy analysis of the AZURE (BIG 01/04) randomised open-label phase 3 trial

BACKGROUNDnThe role of adjuvant bisphosphonates in early breast cancer is uncertain. We therefore did a large randomised trial to investigate the effect of the adjuvant use of zoledronic acid on disease-free survival (DFS) in high-risk patients with early breast cancer.nnnMETHODSnIn the AZURE trial, an open-label, international, multicentre, randomised, controlled, parallel-group phase 3 trial, women (age ≥18 years) with stage II or III breast cancer were randomly assigned (1:1) by a central automated 24-h computer-generated telephone minimisation system (balanced for number of involved axillary lymph nodes, tumour stage, oestrogen receptor status, type and timing of systemic therapy, menopausal status, statin use, and treatment centre) to receive standard adjuvant systemic treatment alone (control group) or with 4 mg intravenous zoledronic acid every 3-4 weeks for six doses, then every 3 months for eight doses, followed by every 6 months for five doses, for a total of 5 years of treatment. The primary endpoint was disease-free survival (DFS). Secondary endpoints were invasive DFS (IDFS), overall survival, time to bone metastases, time to distant recurrence, and subgroup analyses of variables included in the randomisation. All patients have completed study treatment. Results from the intention-to-treat final analysis of this fully recruited study are presented after a median follow-up of 84 months (IQR 66-93). This final efficacy analysis was planned to take place after 940 DFS events. This trial is registered with ClinicalTrials.gov, NCT00072020.nnnFINDINGSn3360 women were recruited from 174 centres in seven countries between Sept 4, 2003, and Feb 16, 2006. The number of DFS events did not differ between groups: 493 in the control group and 473 in the zoledronic acid group (adjusted hazard ratio [HR] 0·94, 95% CI 0·82-1·06; p=0·30). IDFS (HR 0·93, 95% CI 0·82-1·05; p=0·22), overall survival (0·93, 0·81-1·08; p=0·37), and distant recurrences (0·93, 0·81-1·07; p=0·29) were much the same in both groups. Zoledronic acid reduced the development of bone metastases, both as a first event (HR 0·78, 95% CI 0·63-0·96; p=0·020) and at any time during follow-up (0·81, 0·68-0·97; p=0·022). The effects of zoledronic acid on DFS were not affected by oestrogen-receptor status. However, zoledronic acid improved IDFS in those who were over 5 years since menopause at trial entry (n=1041; HR 0·77, 95% CI 0·63-0·96) but not in all other (premenopause, perimenopause, and unknown status) menopausal groups (n=2318; HR 1·03, 95% CI 0·89-1·20). 33 cases of suspected osteonecrosis of the jaw have been reported, with 26 confirmed on central review, all in the zoledronic acid group (1·7%, 95% CI 1·0-2·4).nnnINTERPRETATIONnThese results suggest no overall benefit from the addition of zoledronic acid to standard adjuvant treatments for early breast cancer. However, zoledronic acid does reduce the development of bone metastases and, for women with established menopause, improved disease outcomes.nnnFUNDINGnNovartis Global and NIHR Cancer Research Network.

Adjuvant bisphosphonates in early breast cancer: consensus guidance for clinical practice from a European Panel

Bisphosphonates have been studied in randomised trials in early breast cancer to investigate their ability to prevent cancer treatment-induced bone loss (CTIBL) and reduce the risk of disease recurrence and metastasis. Treatment benefits have been reported but bisphosphonates do not currently have regulatory approval for either of these potential indications. This consensus paper provides a review of the evidence and offers guidance to breast cancer clinicians on the use of bisphosphonates in early breast cancer. Using the nominal group methodology for consensus, a systematic review of the literature was augmented by a workshop held in October 2014 for breast cancer and bone specialists to present and debate the available pre-clinical and clinical evidence for the use of adjuvant bisphosphonates. This was followed by a questionnaire to all members of the writing committee to identify areas of consensus. The panel recommended that bisphosphonates should be considered as part of routine clinical practice for the prevention of CTIBL in all patients with a T score of <-2.0 or ≥2 clinical risk factors for fracture. Compelling evidence from a meta-analysis of trial data of >18,000 patients supports clinically significant benefits of bisphosphonates on the development of bone metastases and breast cancer mortality in post-menopausal women or those receiving ovarian suppression therapy. Therefore, the panel recommends that bisphosphonates (either intravenous zoledronic acid or oral clodronate) are considered as part of the adjuvant breast cancer treatment in this population and the potential benefits and risks discussed with relevant patients.

Neoadjuvant Chemotherapy with or without Zoledronic Acid in Early Breast Cancer—A Randomized Biomarker Pilot Study

Purpose: To investigate the short-term biologic effects of neoadjuvant chemotherapy +/− zoledronic acid (ZOL) in invasive breast cancer. Experimental Design: Forty patients were randomized to receive a single 4 mg infusion of ZOL 24 hours after the first cycle of FE100C chemotherapy, or chemotherapy alone. Randomization was stratified for tumor stage, ER, HER2, and menopausal status. All patients had repeat breast core biopsy at day 5 (D5) ± day 21 (D21). Effects on apoptotic index, proliferation (Ki67), growth index, surrogate serum markers of angiogenesis (VEGF), and serum reproductive hormones within the TGFβ family (activin-A, TGFβ1, inhibin-A, and follistatin) were evaluated and compared. Results: Baseline clinicopathologic characteristics were well balanced. Cell growth index (increased apoptosis and reduced proliferation) fell at D5 in both groups but recovered more rapidly with chemotherapy + ZOL compared with chemotherapy alone by D21 (P = 0.006). At D5, a greater reduction in serum VEGF occurred with chemotherapy + ZOL compared with chemotherapy: median percentage change −23.8% [interquartile range (IQR): −32.9 to −15.8] versus −8.4% (IQR: −27.3 to +8.9; P = 0.02), but these effects were lost by D21. Postmenopausal women showed a decrease in follistatin levels from baseline in the chemotherapy + ZOL group at D5 and D21, compared with chemotherapy alone (Pinteraction = 0.051). Conclusions: In this pilot study, short-term changes in biomarkers suggest potentially relevant interactions between tumor biology, chemotherapy, modification of the bone microenvironment, and the endocrine status of the host. Larger studies with more frequent dosing of zoledronic acid are needed to assess these complex interactions more thoroughly. Clin Cancer Res; 19(10); 2755–65. ©2013 AACR.

Abstract S6-4: Vitamin D, but not bone turnover markers, predict relapse in women with early breast cancer: an AZURE translational study.

Background: The AZURE trial evaluated the addition of zoledronic acid (ZOL) to standard adjuvant therapy on relapse rates and survival in pts with stage II/III breast cancer. While the overall analysis reported no benefit, a pre-planned subgroup analysis showed significant benefits in postmenopausal (PM) women. Here we report whether baseline measurements of 25-hydroxyvitamin D (25-OHD) and the serum bone turnover markers N-terminal propeptide type I procollagen (P1NP) and beta C-terminal telopeptide type I collagen (β-CTX) can identify pts at high risk of relapse and/or modify the treatment effects of ZOL. Methods: 872 AZURE pts consented for serum to be collected and stored for translational research projects (ZOL group n=431; control group n=441). Serum P1NP, β-CTX and 25-OHD levels were measured in 867, 863 and 856 pts respectively. These markers were analysed as categorical variables with determined cut-off points to predict bone as 1st site of distant recurrence (DR) or any distant relapse (P1NP (ng/ml), >70 versus ≤70; βCTX (ng/ml), >0.299 versus ≤0.299; 25-OHD (ng/ml), ≤30 versus >30). Additionally, the markers were assessed for an interaction with ZOL. Analyses were adjusted for systemic therapy, lymph node and ER status. As in previous analyses of AZURE, the PM cohort was defined as ≥5 years since last menses; all other patients are included in a “not postmenopausal” (not-PM) group. Results: The baseline disease characteristics of the translational cohort were similar to those of the total AZURE population and showed a similar benefit of ZOL among the PM patients: hazard ratio (HR) for DR = 0.61 (95% CI 0.35, 1.07; p-value for interaction with not-PM women = 0.0173). At a median follow-up of 53.3 months, 150 pts have had a 1st DR event; 47 had bone-only relapse, 19 bone plus other distant site and 84 developed non-bone DR. Mean value of 25-OHD (ng/ml) was 18.30 (range, 3.16–54.82; SD=9.19) with 61.0% of pts 30. 25-OHD levels >30 ng/ml were significantly associated with lower risk for bone relapse (HR 0.11, 95% CI 0.02, 0.76; p-value 0.0257). A similar trend was seen for any site of DR (HR 0.56, 95% CI 0.31, 1.01; p-value = 0.0519). Additionally, 25-OHD levels were prognostic for bone relapse when analysed as a continuous value (HR 0.97, 95% CI 0.94, 1.00; p-value = 0.0474). Finally, 25-OHD levels >30 ng/ml predicted for benefit of treatment with ZOL in PM women with regards to DR (HR 0.09, 95% CI 0.01, 0.82; interaction p-value 0.0747) but the trend was not seen in not-PM women. Mean values for P1NP and βCTX (range; SD) were 59.1 ng/ml ( Conclusions: High pre-treatment serum levels of 25-OHD are associated with lower risk for bone relapse with a trend for any DR. Amongst PM women, high levels can additionally predict improved outcomes for treatment with ZOL. P1NP and βCTX failed to significantly discriminate breast cancer pts who may be at high risk for DR. Our results suggest that baseline bone turnover is not directly associated with the benefits of ZOL amongst PM women. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S6-4.

The differential anti-tumour effects of zoledronic acid in breast cancer – evidence for a role of the activin signaling pathway

BackgroundNeo-adjuvant breast cancer clinical trials of zoledronic acid (ZOL) have shown that patients with oestrogen negative (ER-ve) tumours have improved disease outcomes. We investigated the molecular mechanism behind this differential anti-tumour effect according to ER status, hypothesising it may in part be mediated via the activin signaling pathway.MethodsThe effects of activin A, its inhibitor follistatin and zoledronic acid on proliferation of breast cancer cells was evaluated using either an MTS proliferation assay or trypan blue. Secretion of activin A and follistatin in conditioned medium (CM) from MDA-MB-231, MDA-MB-436, MCF7 and T47D cell lines were measured using specific ELISAs. The effects of ZOL on phosphorylation domains of Smad2 (pSmad2cu2009+u2009pSmad2L) were evaluated using immunofluorescence. Changes seen in vitro were confirmed in a ZOL treated subcutaneous ER-ve MDA-MB-436 xenograft model.ResultsActivin A inhibits proliferation of both ER-ve and oestrogen positive (ERu2009+u2009ve) breast cancer cells, an effect impaired by follistatin. ZOL significantly inhibits proliferation and the secretion of follistatin from ER-ve cells only, which increases the biological activity of the canonical activin A pathway by significantly increasing intracellular pSmad2c and decreasing nuclear accumulation of pSmad2L. In vivo, ZOL significantly decreases follistatin and pSmad2L expression in ER-ve subcutaneous xenografts compared to saline treated control animals.ConclusionsThis is the first report showing a differential effect of ZOL, according to ER status, on the activin pathway and its inhibitors in vitro and in vivo. These data suggest a potential molecular mechanism contributing to the differential anti-tumour effects reported from clinical trials and requires further evaluation in clinical samples.

Bone Biomarkers in Research and Clinical Practice

Biochemical markers (biomarkers) are increasingly being used in clinical practice. Bone biomarkers have been developed from collagen metabolism and other pathways which report on different aspects of the status of bone formation, bone resorption and bone remodelling. Simple assays for these markers in blood and urine have been developed. Markers for both bone resorption and formation have been correlated with the presence of metastatic bone disease and with its associated skeletal complications, such as pain and fracture and predictive models have been developed which are able to assess the risk of such complications in individual patients. Bone biomarkers are also very useful in monitoring therapy using bisphosphonates and other bone-specific drugs and trials are underway to assess the possible role of bone biomarkers in directing anti-resorptive therapy. Bone biomarkers have played and continue to play a role in development of new bone-specific therapies, such as RANK-ligand inhibitors and cathepsin K. Further novel and more specific bone markers may be anticipated as modern techniques such as proteomics are increasingly applied in this field.

The endocrine influence on the bone microenvironment in early breast cancer

Multiple factors influence the survival of disseminated breast tumour cells (DTCs) in bone. Whereas gene signature studies have identified genes that predict a propensity of tumours to metastasise to bone, the bone environment is key in determining the fate of these tumour cells. Breast cancer cells locate to specific niches within the bone that support their survival, regulated by host factors within the bone microenvironment including bone cells, cells of the bone micro vasculature, immune cells and the extracellular matrix. Reproductive endocrine hormones that affect bone and clinical studies across the menopausal transition have provided comprehensive understanding of the changes in the bone microenvironment during this time. Menopause is characterized by a decrease in ovarian oestradiol and inhibins, with an increase in pituitary follicle-stimulating hormone and this review will focus on the role of these three hormones in determining the fate of DTCs in bone. Both in vivo and clinical data suggest that premenopausal bone is a conducive environment for growth of breast cancer cells in bone. Adjuvant cancer treatment aims to reduce the risk of tumour recurrence by affecting DTCs. Drugs targeting the bone resorbing osteoclasts, such as bisphosphonates, have therefore been evaluated in this setting. Both preclinical and adjuvant clinical studies have shown that bisphosphonates ability to decrease tumour growth in bone is influenced by the levels of endocrine hormones, with enhanced effects in a postmenopausal bone microenvironment. The challenge is to understand the molecular mechanisms behind this phenomenon and to evaluate if alternative adjuvant bone-targeted therapies may be effective in premenopausal women.

Adjuvant zoledronic acid reduces fractures in breast cancer patients; an AZURE (BIG 01/04) study

The fracture impact of adjuvant bisphosphonates in breast cancer is not defined with most trials reporting changes in bone mineral density as a surrogate. The AZURE trial (ISRCTN79831382) evaluated the impact of adjuvant zoledronic acid (ZOL) on fractures. The AZURE trial is an academic, multi-centre, randomised phase III study evaluating the addition of ZOL 4xa0mg to standard therapy (neo/adjuvant chemotherapy and/or endocrine therapy) for 5 years (administered by intravenous (iv) infusion every 3-4 weeks for 6 doses, then 3 monthlyxa0×xa08 and 6 monthlyxa0×xa05) in patients with stage II/III early breast cancer. Fracture data collected as part of skeletal-related adverse event reporting were analysed after a median of 84.2 months of follow-up and 966 disease-free survival (DFS) events. We assessed number of fractures, time-to-first fracture and the incidence of fractures before and after disease recurrence. Two hundred forty-four patients reported ≥1 fracture, 140 (8.3%) in the control arm (171 fractures) and 104 (6.2%) in the ZOL arm (120 fractures). Of the 291 fractures reported, 207 fractures occurred in the absence of recurrence (control 111, ZOL 96), 80 after recurrence (control 59, ZOL 21). The 5-year fracture rate was reduced from 5.9% (95%CI 4.8, 7.1%; control) to 3.8% (95%CI 2.9, 4.7%) with ZOL. ZOL significantly increased time-to-first fracture (HR 0.69, 95%CI 0.53-0.90; Pxa0=xa00.0053) but the majority of fracture prevention benefit occurred after a DFS event (HR 0.3; 95%CI 0.17, 0.53; Pxa0<xa00.001). Fracture benefits from ZOL were similar across menopausal sub-groups. In conclusion, adjuvant ZOL reduced the risk of clinical fractures, the majority of this protection occurred after disease recurrence.

Goserelin, as an ovarian protector during (neo)adjuvant breast cancer chemotherapy, prevents long term altered bone turnover

Background The Ovarian Protection Trial In Premenopausal Breast Cancer Patients “OPTION” trial (NCT00427245) was a prospective, multicenter, randomised, open label study evaluating the frequency of primary ovarian insufficiency (POI) at 12 months in women randomised to 6–8 cycles of (neo)adjuvant chemotherapy (CT) +/− goserelin (G). Here we report the results of a secondary endpoint analysis of the effects of CT+/-G on markers of bone turnover. Methods Serum for bone alkaline phosphatase (BALP) and urine for N-terminal telopeptide (NTX) were collected at baseline, 6, 12, 18, 24 and 36 months. Changes in median levels of bone turnover markers were evaluated for the overall population, according to age stratification at randomisation (≤40 vs >40 years) and with exploratory analysis according to POI rates at 12 months. Results In the overall population, there was a significant increase in NTX at 6 months compared to baseline in patients treated with CT+G (40.81 vs 57.82 p=0.0074) with normalisation of levels thereafter. BALP was significantly increased compared to baseline at 6 months and 12 months in those receiving CT+G, but normalised thereafter. BALP remained significantly higher compared to baseline at 12, 24 and 36 months in patients receiving CT, resulting in a significant difference between treatment groups at 36 months (CT+G 5.845 vs CT 8.5 p=0.0006). These changes were predominantly seen in women >40 years. Women with POI at 12 months showed altered bone formation compared to baseline levels for a longer duration than women who maintained menses. Conclusion Addition of G to CT increases bone turnover during treatment with normalisation after cessation of treatment suggesting G may offer sufficient ovarian protection against CT induced POI to negate longstanding altered bone turnover associated with POI.

Benefits and risks of adjuvant treatment with zoledronic acid in stage II/III breast cancer. 10 years follow-up of the AZURE randomized clinical trial (BIG 01/04)

Adjuvant bisphosphonates improve disease outcomes in postmenopausal early breast cancer (EBC) but the long-term effects are poorly described. The AZURE trial (ISRCTN79831382) was designed to determine whether adjuvant zoledronic acid (ZOL) improves disease outcomes in EBC. Previous analyses showed no effect on overall outcomes but identified benefits in postmenopausal women. Here we present the long-term risks and benefits of adjuvant ZOL with 10-years follow-up. Patients and methods 3360 patients with stage II/III breast cancer were included in an academic, international, phase III, randomized, open label trial. Patients were followed up on a regular schedule until 10 years. Patients were randomized on a 1:1 basis to standard adjuvant systemic therapyu202f+/− intravenous ZOL 4u202fmg every 3–4 weeks x6, and then at reduced frequency to complete 5 years treatment. The primary outcome was disease free survival (DFS). Secondary outcomes included invasive DFS (IDFS), overall survival (OS), sites of recurrence, skeletal morbidity and treatment outcomes according to primary tumor amplification of the transcription factor, MAF. Pre-planned subgroup analyses focused on interactions between menopausal status and treatment effects. Results With a median follow up of 117 months [IQR 70.4–120.4), DFS and IDFS were similar in both arms (HRDFSu202f=u202f0.94, 95%CIu202f=u202f0.84–1.06, pu202f=u202f0.340; HRIDFSu202f=u202f0.91, 95%CIu202f=u202f0.82–1.02, pu202f=u202f0.116). However, outcomes remain improved with ZOL in postmenopausal women (HRDFSu202f=u202f0.82, 95%CIu202f=u202f0.67–1.00; HRIDFSu202f=u202f0.78, 95%CIu202f=u202f0.64–0.94). In the 79% of tested women with a MAF FISH negative tumor, ZOL improved IDFS (HRIDFSu202f=u202f0.75, 95%CIu202f=u202f0.58–0.97) and OS HROSu202f=u202f0.69, 95%CIu202f=u202f0.50–0.94), irrespective of menopause. ZOL did not improve disease outcomes in MAF FISHu202f+u202ftumors. Bone metastases as a first DFS recurrence (BDFS) were reduced with ZOL (HRB-DFSu202f=u202f0.76, 95%CIu202f=u202f0.63–0.92, pu202f=u202f0.005). ZOL reduced skeletal morbidity with fewer fractures and skeletal events after disease recurrence. 30 cases of osteonecrosis of the jaw in the ZOL arm (1.8%) have occurred. Conclusions Disease benefits with adjuvant ZOL in postmenopausal early breast cancer persist at 10 years of follow-up. The biomarker MAF identified a patient subgroup that derived benefit from ZOL irrespective of menopausal status.