ON-treatment Single-cell Analysis for the Identification of Early Tumor Response Biomarkers on Prospective Collected Serial Tumor Biopsies in Triple Negative Breast Cancer Patient During Standard Neoadjuvant Chemo-immunotherapy

NCT07597642 | Not Yet Recruiting DMC

• 1 other identifier: ONSET
• Study Type: interventional
• Target: 55
• Locations: 1 country
• Sites: 1

Brief Summary

This study explores early breast cancer, focusing on triple-negative and high-risk luminal subtypes. It combines single-cell RNA sequencing and spatial imaging of tumor samples collected at different time points during treatment. The aim is to better understand how cancer cells and immune cells interact and to identify biomarkers that can predict whether a patient will respond to chemo-immunotherapy or develop resistance. The study assumes that early molecular and spatial changes at the single-cell level can predict treatment response. This knowledge could help doctors adapt therapies, avoiding unnecessary treatment while improving effectiveness. The project seeks to reveal, for the first time, how cellular diversity and spatial relationships contribute to treatment resistance and disease progression. Tumor samples will be analyzed before treatment, after the first treatment cycle (C1D1), and at surgery. Only the biopsy taken after C1D1 is collected specifically for this study; all other samples come from routine clinical care.

Conditions

Breast Cancer Early Stage Breast Cancer (Stage 1-3)

Keywords

triple negative or high-risk luminal (ER+/HER2) subtypes

Outcome Measures

Primary Outcomes (1)

• To characterize the dynamic changes in tumor and immune cell populations in TNBC and to prospectively collect serial samples from high-risk luminal (ER+/HER2-) breast cancer patients.

  Gene expression levels per single-cell and relative cell clustering (%) by comparing pre-treatment, on-treatment (after first cycle of standard of care neoadiuvant therapy), and post-treatment (surgery or residual disease)

  Pre-treatment, on-treatment (after first cycle of therapy), and post-treatment (surgery or residual disease)

Other Outcomes (1)

• To correlate single-cell gene expression data with pCR and RD to identify predictive signatures of therapy response

  Across all collected timepoints (baseline, after C1 of neadiuvant standard of care therapy and at surgery)

Interventions

on treatment biopsy (after C1) PROCEDURE

Serial tumor tissue collection and analysis for the identification of early tumor response biomarkers. Tumor samples will be obtained at three predefined time points: (i) prior to initiation of treatment (baseline biopsy), (ii) after Cycle 1 Day 1 (C1D1) of therapy, and (iii) at the time of surgery (surgical specimen)

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Female patients aged ≥18 years.
• ECOG performance status 0-1.
• Histologically confirmed early breast cancer with one of the following molecular profiles:
• TNBC: ER and PR negative (IHC \<10%) and HER2 negative (IHC 0-1+ or FISH non-amplified).
• High-risk luminal (ER+/HER2-): ER positive (IHC ≥10%) HER2 negative (IHC 0-1+ or FISH non-amplified), with high-risk features (e.g., Grade 3, PR-negative, high proliferation, high TILS).
• Clinical indication for neoadjuvant treatment according to standard practice:
• TNBC: cT1c and/or cN positive, or cT2 (\>2 cm) and/or cN positive (stage II,III).
• High-risk luminal: features as defined above (Grade 3, PR-negative, high proliferation, ER low).
• Ability to understand and sign written informed consent for participation in the study, approved by the local Ethics Committee.

You may not qualify if:

• HER2-positive tumors.
• Known metastatic disease. 4 Clinical contraindications to the planned neoadjuvant therapy.
• \. Decision for upfront surgery as determined by the multidisciplinary team. 6. Inability to provide informed consent. 7. Pregnancy or breastfeeding. 8. Prior systemic therapy (chemotherapy, immunotherapy, or endocrine therapy) for the current breast cancer before baseline biopsy 9. On-treatment biopsy clinically not feasible or controindicated

Sponsors & Collaborators

• IRCCS San Raffaele: lead

Study Sites (1)

IRCCS Ospedale San Raffaele

Milan, Lombardy, 20132, Italy

Location

Central Study Contacts

Giulia Viale, MD

CONTACT

+390226437627; callcenter.mammella@hsronline.it

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: Patients will receive standard-of-care (SOC) neoadjuvant chemotherapy according to sequential anthracycline and taxane regimens. In addition, patients with triple-negative breast cancer (TNBC) will receive immunotherapy with pembrolizumab as per the KEYNOTE-522 schema. No modifications to the SOC treatments need to be reported. Patients enrolled in the study will undergo a single on-treatment biopsy after the first cycle of neoadjuvant therapy, that is not required as per SOC, and two biopsies (at diagnosis and at surgery) already planned for clinical practice to assess biomarkers predictive of early response/progression with single-cell sequencing technique.
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Medical Oncologist

Model Details: the intervention is about the on treatment biopsy that is not required for standard of care

Study Record Dates

• First Submitted: May 8, 2026
• First Posted: May 19, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): March 1, 2029
• Last Updated: May 19, 2026

Record last verified: 2026-05

Locations

IT (1)