LeStage, Barbara

Importance Although adding immune checkpoint inhibitors to neoadjuvant chemotherapy improves outcomes in high-risk early-stage breast cancer, opportunities remain to further enhance response. Dual checkpoint blockade offers a potential strategy to further enhance efficacy. Objective To evaluate the combination of anti−programmed cell death 1 protein (PD-1) cemiplimab and anti−lymphocyte activation gene 3 (LAG-3) added to neoadjuvant therapy in ERBB2 -negative early-stage, high-risk breast cancer. Design, Setting, and Participants The I-SPY2 (Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis 2) is an ongoing randomized clinical platform trial being conducted at multiple US clinical sites including patients with early-stage (II or III) ERBB2 -negative, high-risk breast cancer. Participants, continuously enrolled since 2010, were adaptively randomized from February 2, 2020, to December 9, 2021, to one of several experimental neoadjuvant therapies or control groups based on receptor subtypes defined by hormone receptor (HR), ERBB2 status, and MammaPrint (Agendia Inc) molecular risk, categorized as high (MP1) or ultrahigh (MP2). Data were analyzed from January 1, 2022, to August 5, 2025. Interventions Both groups received weekly paclitaxel for 12 weeks, then doxorubicin and cyclophosphamide followed by surgery; concomitant with paclitaxel, the intervention group also received 4 doses of cemiplimab and fianlimab (PCF) every 3 weeks. Main Outcomes and Measures Pathologic complete response (pCR). Treatments graduated when they achieved 85% bayesian probability of success in a subtype-specific phase 3 trial. Pathway-specific biomarkers were assessed for response prediction. Results A total of 78 participants (mean [SD] age, 47 [39-54] years) were randomized to the intervention group, with 350 participants (mean [SD] age, 48 [39-57] years) randomized to the historical control population. PCF graduated in all clinical signatures, with pCR rates vs control of 44% (95% CI, 34%-53%) vs 21% (95% CI, 17%-25%) in all ERBB2 , 53% (95% CI, 39%-67%) vs 29% (95% CI, 22%-36%) in triple-negative, and 36% (95% CI, 23%-49%) vs 14% (95% CI, 9%-19%) in HR-positive and ERBB2 -negative disease. Among the total participants, 16 (21%) experienced adrenal insufficiency, including hypophysitis (11% grade 3 or 4), mostly occurring after immunotherapy completion. PCF was found to be highly effective in the subset of patients with immune signature positive status (ImPrint positive). Conclusions and Relevance In this randomized clinical trial, the combination of PD-1 and anti−LAG-3 inhibition with standard NAC was effective in early-stage ERBB2 -negative breast cancer, particularly in patients displaying a positive ImPrint immune signature. These results warrant further definitive trials. Trial Registration ClinicalTrials.gov Identifier: NCT01042379

ABSTRACT Background Guidelines recommend primary care practitioners (“PCPs”) engage women ≥ 75 years in shared decision‐making (SDM) around mammography screening. Therefore, we aimed to develop a web‐based conversation aid about mammography screening for women ≥ 75 using output from established simulation models to provide screening outcomes based on > 23,000 combinations of individual women's health and breast cancer risk factors. Methods We used an end‐user centered design approach to develop a prototype web‐based conversation aid incorporating feedback. From July 2023 to April 2024, 10 PCPs from a Boston‐area health system and a safety‐net hospital used the prototype aid during encounters with women ≥ 75 without breast cancer or dementia ( n = 30; 1–5 patients per PCP). We observed aid use and assessed clinician effort to involve patients in SDM using OPTION5 (assesses five components of SDM, scores range 0–100). We surveyed PCPs and patients about the aid's acceptability. Patients completed the SDM‐process scale (scores range 0–4) to rate the SDM quality experienced. Participants' comments were subject to thematic analysis. Results Of 10 PCP ‐participants, seven were female and four were community‐based. Of 30 patient‐participants, 22 (73%) were non‐Hispanic White, 9 (30%) had ≥ 2 Charlson comorbidities and mean age was 78.5 years ( SD 2.8). Nine PCPs agreed that the aid helped them with SDM and was easy‐to‐use; six felt it had too much information; and seven planned to continue using the aid. Patients rated the SDM ‐process highly (scores = 3.0 [ SD 0.9]) and we observed high SDM (mean OPTION5 = 77.9 [ SD 20.6]). Participants felt the aid was “empowering” and “helpful for decision‐making.” After SDM discussions, seven patients intended to stop screening, nine to screen less frequently, and 14 to continue screening regularly. Conclusions We developed a novel conversation aid that supports SDM about mammography screening with women ≥ 75 years. Lessons learned will guide revisions of a final tool for testing in a clinical trial.