Importance The Breast Cancer Index (BCI) previously identified premenopausal patients with tumors in which the ratio of expression of HOXB13 relative to IL17BR (hereafter, BCI [H/I]–low tumors) as likely to derive greatest benefit from ovarian function suppression (OFS)–containing adjuvant therapy in the Suppression of Ovarian Function Trial (SOFT) trial. Objectives To assess BCI as a predictive biomarker of benefit from exemestane plus OFS vs tamoxifen plus OFS and to validate BCI as a prognostic biomarker for premenopausal patients. Design, Setting, and Participants This prognostic study used a prospective-retrospective translational design within the Tamoxifen and Exemestane (TEXT) and SOFT trials (enrolled November 2003 to April 2011). Blinded BCI testing in all available tumor samples was completed in March 2024. Premenopausal women with hormone receptor–positive breast cancer randomized to tamoxifen plus OFS or exemestane plus OFS who had BCI assessed were included. Analysis occurred from March to August 2024. Exposure 5 years of adjuvant tamoxifen plus OFS or exemestane plus OFS. Main Outcomes and Measures The primary outcomes were breast cancer-free interval (BCFI) for predictive analyses and distant recurrence-free interval (DRFI) for prognostic analyses after a median follow-up of 13 years in the TEXT cohort. Secondary objectives examined the predictive performance of BCI (H/I) in the combined TEXT and SOFT cohort overall and in prespecified clinical subgroups. Results Of 1782 patients in the TEXT study, 1034 (58.0%) had BCI (H/I)–low tumors; 915 (51.3%) of patients had N0 disease and 1077 (60.4%) were younger than 45 years. Patients with BCI (H/I)–low tumors had a 6.6% absolute benefit in 12-year BCFI (HR, 0.61; 95% CI, 0.44-0.85) for exemestane plus OFS vs tamoxifen plus OFS, while those with BCI (H/I)–high tumors had a 6.3% absolute benefit (HR, 0.78; 95% CI, 0.57-1.07; P for interaction = .29). Results were consistent in the combined TEXT plus SOFT cohort (2896 patients) and adjusting for clinicopathological variables. Clinical subgroup analyses consistently showed benefit of exemestane plus OFS vs tamoxifen plus OFS for BCI (H/I)–low tumors, and more variable relative treatment effects among BCI (H/I)–high tumors, including by age. Post hoc exploratory time-varying estimates suggested the treatment × BCI associations may differ in years 0 to 5 vs greater than 5 years. BCI and BCI N+ as continuous indices were prognostic for distant recurrence in N0 (HR, 1.27; 95% CI, 1.11-1.44; P < .001) and N1 (HR, 1.58; 95% CI, 1.21-2.05; P < .001) cancers. The 12-year DRFI was 96.3%, 90.3%, and 84.9% for BCI low-, intermediate-, and high-risk N0 cancers, respectively. Conclusions and Relevance In this study of premenopausal women with hormone receptor–positive breast cancer, BCI (H/I) status did not clearly predict greater benefit of adjuvant exemestane plus OFS vs tamoxifen plus OFS for women with BCI (H/I)–low tumors than for those with BCI (H/I)–high tumors; BCI continuous indices were reconfirmed as prognostic for premenopausal women. These findings support prior results of SOFT, which compared tamoxifen-alone vs OFS with either exemestane or tamoxifen, indicating premenopausal patients with BCI (H/I)–low tumors may benefit from more intensive endocrine therapy.
Abstract OT3-02-07: PATINA: A randomized, open label, phase III trial to evaluate the efficacy and safety of palbociclib + anti-HER2 therapy + endocrine therapy (ET) vs. anti-HER2 therapy + ET after induction treatment for hormone receptor positive (HR+)/H
Abstract Background: Pre-clinical data and results from early phase clinical trials point to synergistic antitumor activity and potential efficacy of palbociclib when given in combination with anti-HER2 therapy (tx). The aim of PATINA is to determine the effect of adding palbociclib to anti-HER2 and ET maintenance after induction tx in the 1st line setting for HR+/HER2+ MBC. Trial Design: The PATINA trial (AFT-38/NCT02947685) is a pivotal, open-label, international, phase III study. Following 6-8 cycles of chemotherapy (taxane or vinorelbine) with anti-HER2 tx for MBC participants will be randomized 1:1 to standard anti-HER2 tx (trastuzumab +/- pertuzumab) in combination with ET with or without palbociclib until disease progression. ET options are either an aromatase inhibitor or fulvestrant. Premenopausal patients (pts) must receive ovarian suppression. The trial is open to men or women with histologically confirmed HR+/HER2+ MBC provided they are without evidence of disease progression by local assessment after induction tx. Total planned accrual is 496 pts. Primary objective is to demonstrate that the combination of palbociclib with anti-HER2 tx plus ET is superior to anti-HER2 tx plus ET alone in prolonging progression-free survival (PFS). Key secondary objectives are measures of tumor control, overall survival, safety and Quality of Life. The main translational science objective is to compare PFS estimates according to PIK3CA mutation status. The study has a 90% power to detect a hazard ratio of 0.667 in favor of the palbociclib arm. All pts approached to participate in PATINA will be asked to share remaining biospecimens and clinical data with the Mastering Breast Cancer Initiative. This initiative was created in order to understand the natural history of MBC and how it envolves over time with the aim to develop new treatments for this patient population. Recruitment has started in 07/2017 and is planned for approximately 22 months in 140 sites in Australia, Germany, Italy, France, New Zealand, Spain, and the US. 69 pts have been recruited so far. The study is sponsored by Alliance Foundation Trials (AFT) and financially supported by Pfizer Citation Format: Metzger O, Mandrekar S, Loibl S, Mundhenke C, Seiler S, Valagussa P, Lim E, Tripathy D, Winer EP, Huang C, Carey L, Francis P, Miller K, Goetz MP, Prat A, Loi S, Krop I, Gianni L, Delalogue S, Vaz-Luis I, Dockter T, Lanzillotti J, Ciruelos E, DeMichele AM. PATINA: A randomized, open label, phase III trial to evaluate the efficacy and safety of palbociclib + anti-HER2 therapy + endocrine therapy (ET) vs. anti-HER2 therapy + ET after induction treatment for hormone receptor positive (HR+)/HER2-positive metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-02-07.
Randomized comparison of adjuvant aromatase inhibitor (AI) exemestane (E) plus ovarian function suppression (OFS) vs tamoxifen (T) plus OFS in premenopausal women with hormone receptor-positive (HR+) early breast cancer (BC): Joint analysis of IBCSG TEXT a
Randomized comparison of adjuvant aromatase inhibitor (AI) exemestane (E) plus ovarian function suppression (OFS) vs tamoxifen (T) plus OFS in premenopausal women with hormone receptor-positive (HR+) early breast cancer (BC): Joint analysis of IBCSG TEXT a
LBA1 Background: Adjuvant endocrine therapy with AI vs T improves outcomes in postmenopausal HR+ BC. TEXT and SOFT were designed to test whether adjuvant AI improves outcomes in premenopausal women with HR+ BC treated with OFS (AI question) and to determine the value of OFS in women who remain premenopausal and are suitable for adjuvant T (OFS question). Methods: TEXT and SOFT, randomized phase 3 trials, enrolled 5,738 premenopausal women with HR+ early BC from Nov03 to Apr11 (2672 TEXT; 3066 SOFT). TEXT randomized women within 12wk of surgery to 5y E+OFS vs T+OFS; chemotherapy (CT) was optional and concurrent with OFS. SOFT randomized women to 5y E+OFS vs T+OFS vs T alone, either within 12wk of surgery if no CT planned, or within 8mo of completing (neo)adjuvant CT. OFS was by choice of 5y triptorelin, oophorectomy, or ovarian irradiation. The primary endpoint is disease-free survival (DFS: randomization until invasive local, regional, distant recurrence, or contralateral breast; 2nd malignancy; death). Due to low event rates, protocol amendments in 2011 changed the analysis plans to answer the AI question (E+OFS vs T+OFS) by joint analysis of TEXT and SOFT. By Q3’2013 with >5y median follow-up, 436 DFS events were projected, providing 84% power for HR=0.75 with E+OFS vs T+OFS (stratified logrank 2-sided α=0.05). Results: At 5.7y median follow-up, 514 (11%) DFS events were reported in the ITT population comparing E+OFS (n=2346) vs T+OFS (n=2344). Patients assigned E+OFS had significantly reduced DFS hazard (HR=0.72; 95% CI, 0.60-0.86; P=0.0002) vs T+OFS; 5y DFS was 91.1% vs 87.3%. Reductions were similar for secondary endpoints of BC-free interval (HR=0.66 (0.55-0.80) 5y BCFI 92.8% vs 88.8%) and distant recurrence-free interval (HR=0.78 (0.62-0.97)), though not overall survival (HR=1.14 (0.86-1.51)) at this early follow-up (194 (4%) deaths). Grade 3-4 targeted AEs were reported in 31% E+OFS vs 29% T+OFS patients. Conclusion: In premenopausal women with HR+ BC, adjuvant treatment with E+OFS significantly reduced the risk of recurrence compared to T+OFS. Clinical trial information: NCT00066703 / NCT00066690 .