Parsons, Heather A.

ASCO Guidelines provide recommendations with comprehensive review and analyses of the relevant literature for each recommendation, following the guideline development process as outlined in the https://www.asco.org/practice-patients/guidelines/guideline-methodology . ASCO Guidelines follow the https://www.asco.org/about-asco/legal/conflict-interest-coi . Clinical Practice Guidelines and other guidance (“Guidance”) provided by ASCO is not a comprehensive or definitive guide to treatment options. It is intended for voluntary use by clinicians and should be used in conjunction with independent professional judgment. Guidance may not be applicable to all patients, interventions, diseases or stages of diseases. Guidance is based on review and analysis of relevant literature, and is not intended as a statement of the standard of care. ASCO does not endorse third-party drugs, devices, services, or therapies and assumes no responsibility for any harm arising from or related to the use of this information. See complete disclaimer in Appendix 1 and Appendix 2 (online only) for more . PURPOSE To offer clinicians recommendations concerning breast cancer follow-up and surveillance after primary treatment. METHODS ASCO convened an Expert Panel to develop recommendations based on a systematic review and a formal consensus process. RESULTS One randomized controlled trial (RCT) was identified and formed the evidentiary basis for the surveillance mammography guideline recommendation. No RCTs were identified that evaluated different follow-up approaches by risk of relapse in patients treated for early-stage breast cancer. Given the dearth of evidence identified in the systematic review of the literature, formal modified Delphi consensus-based recommendations were generated. RECOMMENDATIONS The guideline offers recommendations on the role of a risk-based approach to the frequency and intensity of follow-up among patients with breast cancer in the adjuvant setting. Regular history, physical examination, and mammography are recommended for breast cancer follow-up. Either virtual or in-person visits can be offered. Certain patients at a high risk of cancer recurrence warrant closer surveillance, such as those patients with locally advanced disease or residual disease following neoadjuvant chemotherapy. Recommendations on the use of blood-based biomarkers and supplemental imaging are provided. Guideline recommendations will be updated once additional evidence-based tools become available to better individualize surveillance. Additional information is available at www.ascopubs.org/topics/asco-guidelines/breast-cancer .

TPS1147 Background: Due to dramatic improvements in neoadjuvant and adjuvant HER2-directed therapy (tx), most patients (pts) with early HER2+ breast cancer are cured. As a result, over half of pts newly diagnosed with HER2+ metastatic breast cancer (MBC) now present with de novo stage IV disease. Anti-HER2 tx has also significantly extended survival for pts with HER2+ MBC, with a subgroup of exceptional responders alive many years (yrs) after diagnosis. However, the paradigm for HER2+ MBC remains non-curative, and pts receive tx indefinitely with significant toxicities and costs. The SAPPHO study is investigating whether an intensification approach of sequential, non-cross resistant anti-HER2 tx followed by tx discontinuation is associated with long-term disease control in pts with HER2+ MBC. Methods: SAPPHO is an open-label, phase II, single-arm trial testing a sequential regimen of non-cross resistant, HER2-targeted tx with curative intent in pts with de novo HER2+ MBC. Eligible pts must have biopsy-proven, de novo MBC with high HER2 expression (3+ by immunohistochemistry). Pts with brain metastases are eligible upon receipt of local tx. Treatment consists of an induction regimen (trastuzumab-pertuzumab-taxane [THP] x 4 cycles, followed by trastuzumab deruxtecan [TDXd] x 6 cycles, followed by trastuzumab emtansine [TDM1]-tucatinib x 4 cycles), followed by a maintenance regimen (HP-tucatinib for 1 yr). Given results from DESTINY-Breast09, the sequence of TDXd-P x 6 cycles followed by THP x 4 followed by TDM1-tucatinib x 4 can be chosen as alternative induction tx per investigator and patient choice. Pts who remain progression-free after completing maintenance will stop all anti-HER2 tx. Endocrine tx will be continued for pts with hormone receptor+/HER2+ tumors. Tumor specimens from breast and a metastatic site are collected at baseline and the end of induction. Serial plasma samples for ctDNA analysis are collected at baseline, during treatment, and during follow-up. The primary endpoint is the probability of being progression-free and off anti-HER2 tx 4 yrs from the start of induction. With a sample size of 72 pts, the study is designed to have 91% power to reject the null hypothesis that the probability of being off anti-HER2 tx and progression-free is less than 24%, with an alternative hypothesis of 40%. Key secondary endpoints are overall survival, overall response rate by modified RECIST 1.1 after induction, and safety. Correlative endpoints include the relationship between ctDNA dynamics and outcomes. Patient-reported outcomes will be analyzed, including quality of life, illness intrusiveness, financial toxicity, anxiety, distress about cancer progression, perception of benefit and risk of progression. SAPPHO began enrollment in Q3 2024, and the study is open at 4 US sites within the Translational Breast Cancer Research Consortium (NCT05721248). Clinical trial information: NCT05721248 .

Importance Molecular analyses of biospecimens collected from study participants are essential for identifying biomarkers that can tailor treatments to specific subsets of patients who are most likely to benefit. Sharing of data and biospecimens from clinical trials enables personalized, patient-centric use of cancer therapies and accelerates the development of new treatments. Objective To describe obstacles to sharing data and biospecimens and to propose strategies to enhance access and collaboration. Evidence Review This is a Special Communication authored by 53 academic investigators and patient representatives from the breast cancer community with extensive experience in conducting clinical and translational research. The article also evaluates the impact of biomarker research on specifying responsive subpopulations in the 29 registrational clinical trials that have led to approval of a new drug for treatment of breast cancer between 2017 and 2024. Findings Clinical trial participants are increasingly asked to provide tissue and/or body fluid biospecimens for biomarker research that is typically controlled by the sponsoring pharmaceutical company, but published biomarker studies are rare. Among 29 breast cancer registrational studies reported in the past 8 years, none resulted in biomarker research that restricted a drug’s approved indication. Herein, strategies to maximize the value of clinical data and biospecimens contributed by participants are proposed, thereby supporting the shared goals of the pharmaceutical industry and academia to improve patient care. These strategies include (1) establishing coleadership structures involving academia and patients in clinical trial design and conduct, (2) ensuring that informed consent forms state that data and biospecimens will be shared with academia for future research, (3) requiring the sharing of clinical data as a condition for regulatory approval, and (4) enabling access to biospecimens and translational research data for independent studies on biomarkers that may indicate drug efficacy and toxicity. Conclusions and Relevance Data and biospecimen sharing from registrational trials has been suboptimal. Improving clinical data, biospecimens, and biospecimens’ related data sharing requires concrete actions and a multidimensional stakeholder approach to accelerate the impact of clinical cancer research on the quality of patient care.

TPS1127 Background: Patients with estrogen receptor-positive (ER+) metastatic breast cancer (mBC) may develop resistance to endocrine therapy (ET), particularly following treatment with a cyclin-dependent kinase 4/6 inhibitor (CDK4/6i), potentially driven by a mutation in the ERa-coding gene, ESR1. Lasofoxifene (LAS), an oral, next-generation ET and ER breast antagonist, was evaluated in two phase 2 studies of women with ER+/HER2- mBC and an ESR1 mutation who had disease progression on previous ET and CDK4/6i. The ELAINE 1 trial showed numerically greater progression-free survival (PFS, median ~6 vs 4 mos; P=0.138), objective response rate (ORR, 13% vs 3%; P=0.124), and clinical benefit rate (CBR, 37% vs 22%; P=0.117) with LAS monotherapy versus the ER degrader fulvestrant (fulv), with a favorable safety profile (1). The single-arm, ELAINE 2 trial demonstrated that LAS plus abemaciclib (Abema) was well tolerated with a median PFS of ~13 mos, ORR of 56%, and CBR of 66% (2). Based on these data, the phase 3, registrational, ELAINE 3 trial was initiated. Methods: ELAINE 3 (NCT05696626) is an open-label, phase 3, multicenter study evaluating the efficacy, safety, and tolerability of LAS plus Abema versus fulv plus Abema. Key inclusion criteria are pre- and postmenopausal women and men aged ≥18 yrs; ER+/HER2-, locally advanced and/or mBC (measurable and/or non-measurable disease); ≥1 acquired ESR1 mutation; progression on an aromatase inhibitor plus palbociclib or ribociclib as their first hormonal treatment for advanced/mBC; and ≤1 line of chemotherapy in the advanced/metastatic setting. Patients will be randomized 1:1 to receive LAS 5 mg/day plus Abema 150 mg BID, or fulv 500 mg IM on days 1, 15, and 29, then once monthly plus Abema 150 mg BID. Treatment will continue until progression, death, unacceptable toxicity, or withdrawal from the study. The primary endpoint is PFS; key secondary endpoints are ORR, overall survival, CBR, duration of response, and time to response. Time to cytotoxic chemotherapy, quality of life, and safety will also be evaluated. Blood samples for circulating tumor DNA (ctDNA) will be collected for genomic analyses at screening, at weeks 4 and 8 and every 8 weeks thereafter, and at the final visit. Outcomes with LAS/Abema and fulv/Abema will be compared using a stratified Cox proportional hazards model and stratified logrank test. Expected PFS is ≥10.3 mos for LAS/Abema and 7 mos for fulv/Abema (PFS hazard ratio of 0.68 at final analysis). The target sample size is 400, to achieve 90% power with a one-sided type I error rate of 0.025 after 285 PFS events. Full recruitment is expected to occur over 18 mos at approximately 125 global sites. 1. Goetz MP, et al. Ann Oncol. 2023;34:1141-1151. 2. Damodaran S, et al. Ann Oncol. 2023;34:1131-1140. Clinical trial information: NCT05696626 .

Abstract BACKGROUND: Anti-HER2 therapies have transformed the trajectory for patients with HER2-positive (HER2+) MBC. A subset of patients with HER2+ MBC do exceptionally well and remain on maintenance anti-HER2 therapy for many years. However, current therapy is non-curative and patients are treated indefinitely. While these therapies often are well-tolerated, they may cause significant toxicities, are expensive, and typically require frequent infusion and provider visits. Case reports and retrospective series demonstrate that some patients may do well after stopping anti-HER2 treatment. We currently lack prospective data on the likelihood of clinical impact of successful treatment discontinuation, outcomes among patients who progress and restart HER2-directed therapy, and tools to predict who may safely stop therapy. In this study, we will enroll pts with an exceptional response to anti-HER2 therapy. Pts may elect to either continue or stop anti-HER2 therapy and will be followed clinically and radiographically on a protocol-specified schedule. Considering the central role of patients in choosing the study intervention arm, and the unique nature of stopping therapy as a treatment intervention, patient advocates have been deeply involved in the study design to ensure patient concerns are being heard and addressed. We will retrospectively assess minimal residual disease (MRD), measured in plasma, as a biomarker of ongoing response, in a step toward shifting the treatment paradigm for pts with HER2+ MBC. METHODS: STOP-HER2 is a prospective, non-randomized, phase II, multicenter study of either continuation (cohort 1) or cessation (cohort 2) of anti-HER2 therapy in exceptional responders with HER2+ MBC. Eligible patients must have biopsy-proven HER2+ MBC by ASCO/CAP guidelines and must have been receiving first-line anti-HER2 therapy for MBC for at least 3 years without evidence of progressive disease (PD) as determined by the treating investigator. Patients with prior brain-only PD or oligo-PD outside the brain are eligible at least 2 years after local treatment to the central nervous system (CNS) and in absence of subsequent PD. Up to fifty-two participants will be enrolled into cohort 2, and an additional thirty participants enrolled into the cohort 1, at 10 US sites within the Translational Breast Cancer Research Consortium. Co-primary endpoints are the 1-year progression-free survival (PFS) in cohorts 2 and 1, separately. Secondary endpoints include the clinical benefit rate upon re-initiation of anti-HER2 therapy for patients in cohort 2 experiencing PD after treatment discontinuation; and 3-year overall survival in both cohorts. Correlative endpoints include MRD status at baseline and the correlation between MRD dynamics and outcomes. Patient-reported outcomes will be collected and analyzed, including quality of life, illness intrusiveness, financial toxicity, anxiety, and decision regret. The study will use a two-stage design to assess the primary objective of estimating the rate of participants who are free of progression at one year after discontinuing anti-HER2 therapy. If 50% or less are free of progression at one year, stopping HER2 therapy would not be considered a viable treatment plan (null hypothesis). The study is designed to have 80% power to reject the null hypothesis at the 10% type I error rate when 68% of exceptional responders are free of progression at one year after stopping HER2 therapy. STOP-HER2 began enrollment in Q2 2023 (NCT05721248). Citation Format: Heather Parsons, Kathryn Ruddy, Stefania Morganti, Karen Smith, Victoria Attaya, Eliza Kallfelz, Michelle DeMeo, Jamie LaScala, Shirley Mertz, Teri Pollastro, Patricia Spears, Adam Brufsky, Chau Dang, Susan Dent, Ahmed Elkhanany, WIlliam Gwin, Ciara O'Sullivan, Kathy Miller, Sara Nunnery, Elaine Walsh, Anna Maria Storniolo, Sara Tolaney, Nabihah Tayob, Antonio Wolff, Eric Winer, Mothaffar Rimawi, Ian Krop, Nancy Lin. The STOP-HER2 Trial: A Phase 2 Study of Stopping Trastuzumab - Outcomes in Patients with HER2+ Metastatic Breast Cancer (TBCRC 062) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-20-01.

Abstract Background: Patients with estrogen receptor-positive (ER+) metastatic breast cancer (BC) may develop resistance to endocrine therapy (ET), particularly following treatment with a cyclin-dependent kinase 4/6 inhibitor (CDK4/6i), potentially driven by a mutation in the ERa-coding gene, ESR1. Lasofoxifene, an oral, next-generation ET and ER breast antagonist, had potent activity in mBC xenograft models expressing ESR1 mutations, either as a single agent or combined with a CDK4/6i. Subsequently, two phase 2 studies evaluated lasofoxifene in women with ER+/HER2- metastatic BC and an ESR1 mutation who had disease progression on previous ET and CDK4/6i. The ELAINE 1 trial showed numerically greater progression-free survival (PFS, median ~6 vs 4 months; P=0.138), objective response rate (ORR, 13% vs 3%; P=0.124), and clinical benefit rate (CBR, 37% vs 22%; P=0.117) with lasofoxifene monotherapy versus the ER degrader fulvestrant, with a favorable safety profile (Goetz MP, et al. Ann Oncol. 2022;33:S1387). The single-arm, ELAINE 2 trial demonstrated that lasofoxifene combined with abemaciclib was well tolerated with a median PFS of ~13 months, ORR of 56%, and CBR of 66% (Damodaran S, et al. J Clin Oncol. 2023;41:suppl 16; abstr 1057). Based on these data, the phase 3, registrational, ELAINE 3 trial was initiated. Methods: ELAINE 3 (NCT05696626) is an open-label, phase 3, multicenter study evaluating the efficacy, safety, and tolerability of lasofoxifene plus abemaciclib versus fulvestrant plus abemaciclib. Key inclusion criteria are pre- and postmenopausal women and men aged ≥18 years; ER+/HER2-, locally advanced and/or metastatic BC (measurable and/or non-measurable disease); ≥1 acquired ESR1 mutation; progression on an aromatase inhibitor plus palbociclib or ribociclib as their first hormonal treatment for advanced/metastatic BC; and ≤1 line of chemotherapy in the advanced/metastatic setting. Patients will be randomized 1:1 to receive lasofoxifene 5 mg/day plus abemaciclib 150 mg BID, or fulvestrant 500 mg IM on days 1, 15, and 29, then 4 weekly plus abemaciclib 150 mg BID. Treatment will continue until progression, death, unacceptable toxicity, or withdrawal from the study. The primary endpoint is PFS; key secondary endpoints are ORR, overall survival, CBR, duration of response, and time to response. Time to cytotoxic chemotherapy, quality of life, and safety will also be evaluated. Blood samples for circulating tumor DNA (ctDNA) will be collected at screening, at weeks 4 and 8 and every 8 weeks thereafter, and at the final visit for genomic analyses. Outcomes with lasofoxifene/abemaciclib and fulvestrant/abemaciclib will be compared using a stratified Cox proportional hazards model and stratified logrank test. Expected PFS is ≥10.3 months for lasofoxifene/abemaciclib and 7 months for fulvestrant/abemaciclib (PFS hazard ratio of 0.68 at final analysis). The target sample size is 400, to achieve 90% power with a one-sided type I error rate of 0.025 after 285 PFS events. Full recruitment is expected to occur over 18 months at 125 global sites. Citation Format: Matthew Goetz, Seth Wander, Thomas Bachelot, Gerald Batist, Javier Cortés, Massimo Cristofanilli, Giuseppe Curigliano, Alexandre de Nonneville, Einav Nili-Gal Yam, Komal Jhaveri, Cynthia Ma, Heather Parsons, Hope Rugo, Sarah Sammons, Daniel Stover, Chris Twelves, Aditya Bardia, Paul V. Plourde, David J Portman, Senthil Damodaran. Trial in progress: Open-label, randomized, multicenter, phase 3, ELAINE 3 study of the efficacy and safety of lasofoxifene plus abemaciclib for treating locally advanced or ER+/HER2- metastatic breast cancer with an ESR1 mutation [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-18-12.

Abstract Introduction: Growing data established the importance of monitoring dynamic changes in circulating tumor DNA (ctDNA) to identify early signs of therapeutic responses, allowing for timely management of treatment to achieve more effective personalized therapy. Higher assay accuracy and consistency, and lower assay cost will support more clinical validation trials and benefit more cancer patients with non-invasive ctDNA NGS tests that can simultaneously map multiple genomic alterations at an affordable price. Method: The NVIGEN X - Precision Cancer Profiling test is a next generation sequencing (NGS) based circulating tumor DNA detection assay using the hybridization capture approach with customized gene panels. Our ctDNA NGS assay was developed with the use of high performance magnetic nanobeads, which enhances assay workflow at key steps including cfDNA extraction, NGS library preparation, and target enrichment. Experiments with individual plasma samples and DNA mutant fragments spiked in plasma samples were carried out to establish the assay performance such as sensitivity, specificity, consistency and data efficiency. NGS data QC metrics of the NVIGEN assay were compared with other assays in peer reviewed publications. Results: We developed a focus 32 gene panel that covers 144 kb of gene regions of clinical significance for breast cancer treatment monitoring and guidance, such as AKT1, ERBB2, PIK3CA, EGFR, ESR1, BRCA1/2, and CD274. Our results demonstrated the capability of NVIGEN X ctDNA NGS assay to detect rare copies (8 cp) of gene mutation at 0.07% MAF from DNA mutant fragments spiked into plasma samples. The NVIGEN X ctDNA NGS assays consistently presented 2-5% duplication rate, >80% on-target rate, <10% CV for key NGS data metrics, and on average required 1.36X paired reads per 1X unique coverage. Compared with the Roche Avenio assays (targeted, expanded and surveillance panels) as published in 2020 which on average required 9.36X paired reads per 1X unique coverage, the NVIGEN X -precision cancer profiling assays demonstrated 85% reduction in NGS data need to generate each unique coverage. Compared with the original Capp-seq data as published in the 2014 Nature Medicine paper which required in average 13.78 or 27.56 paired reads per unique coverage, the NVIGEN X assay demonstrated >90% reduction in NGS data need per unique coverage. Conclusion: The NVIGEN X - Precision Cancer Profiling assay provided high NGS assay performance with high sensitivity, specificity, and consistency, and significantly improved NGS data efficiency. This allows for dramatically reduced assay cost and will help support routine applications of ctDNA NGS tests to improve cancer patient treatment. Experiments of applying NVIGEN X assays for clinical research with patient samples are ongoing and will be presented. Citation Format: Aihua Fu, Wenwu Cui, Minh V. Ton, Kevan Wang, Weiwei Gu, Tianhong Li, Heather A. Parsons, Minetta C. Liu, George W. Sledge. Developing highly sensitive high NGS data efficient ctDNA detection assays for breast cancer surveillance [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-01-15.

PURPOSE Evidence-based treatments for metastatic, human epidermal growth factor receptor 2 (HER2)–positive breast cancer to the CNS are limited. We previously reported modest activity of neratinib monotherapy for HER2-positive breast cancer brain metastases. Here we report the results from additional study cohorts. PATIENTS AND METHODS Patients with measurable, progressive, HER2-positive brain metastases (92% after receiving CNS surgery and/or radiotherapy) received neratinib 240 mg orally once per day plus capecitabine 750 mg/m 2 twice per day for 14 days, then 7 days off. Lapatinib-naïve (cohort 3A) and lapatinib-treated (cohort 3B) patients were enrolled. If nine or more of 35 (cohort 3A) or three or more of 25 (cohort 3B) had CNS objective response rates (ORR), the drug combination would be deemed promising. The primary end point was composite CNS ORR in each cohort separately, requiring a reduction of 50% or more in the sum of target CNS lesion volumes without progression of nontarget lesions, new lesions, escalating steroids, progressive neurologic signs or symptoms, or non-CNS progression. RESULTS Forty-nine patients enrolled in cohorts 3A (n = 37) and 3B (n = 12; cohort closed for slow accrual). In cohort 3A, the composite CNS ORR = 49% (95% CI, 32% to 66%), and the CNS ORR in cohort 3B = 33% (95% CI, 10% to 65%). Median progression-free survival was 5.5 and 3.1 months in cohorts 3A and 3B, respectively; median survival was 13.3 and 15.1 months. Diarrhea was the most common grade 3 toxicity (29% in cohorts 3A and 3B). Neratinib plus capecitabine is active against refractory, HER2-positive breast cancer brain metastases, adding additional evidence that the efficacy of HER2-directed therapy in the brain is enhanced by chemotherapy. For optimal tolerance, efforts to minimize diarrhea are warranted.