Reverse HER2-negative Immune Resistant Breast Cancer

Phase

Condition

N/A

Treatment

anti-PD-1 antibody and chemotherapy

Retinoic Acid

Clinical Study ID

NCT06731140

2411307-7

Ages 18-70
Female

Study Summary

This is a Phase II, open-label study evaluating the efficacy and safety of combined treatment (retinoic acid) with immune checkpoint inhibitor in HER2-negative breast cancer patients who progressed during previous immune checkpoint inhibitors.

Eligibility Criteria

Inclusion

Inclusion Criteria:

ECOG Performance Status of 0, 1, or 2
Metastatic or locally advanced, histologically confirmed luminal breast cancer (defined as: ER positive when immunohistochemistry shows >1% positive tumor cells,PR positive when >1% tumor cells are positive, and HER2 negative when scored as 0-1+or when HER2 2+ shows no amplification by FISH or CISH) or triple negative breastcancer (defined as: ER negative when immunohistochemistry shows <1% positive tumorcells, PR negative when <1% tumor cells are positive, and HER2 negative when scoredas 0-1+ or when HER2 2+ shows no amplification by FISH or CISH).
Radiologic/objective evidence of recurrence or disease progression afterimmunotherapy (combined with targeted therapy or chemo ) for metastatic breastcancer (MBC)
Adequate hematologic and end-organ function, laboratory test results, obtainedwithin 14 days prior to initiation of study treatment.

For women of childbearing potential: agreement to remain abstinent (refrain from heterosexual intercourse) or use contraceptive measures as outlined for each specific treatment arm

Measurable disease according to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST v1.1)
have the cognitive ability to understand the protocol and be willing to participateand to be followed up.

Exclusion

Exclusion Criteria:

Symptomatic, untreated, or actively progressing CNS metastases
Active or history of autoimmune disease or immune deficiency
Significant cardiovascular disease
History of malignancy other than breast cancer within 5 years prior to screening,with the exception of those with a negligible risk of metastasis or death
Treatment with chemotherapy, radiotherapy, immunotherapy or surgery (outpatientclinic surgery excluded) within 3 weeks prior to initiation of study treatment.
Pregnancy or breastfeeding, or intention of becoming pregnant during the study
History of allergies to the drug components of this trial
History of eosinophilosis or mastocytosis
Patients who have been using oral steroid hormones for a long time will need to stopfor 4 weeks if they have used them occasionally in the past

Study Design

anti-PD-1 antibody and chemotherapy

February 12, 2025

October 31, 2027

Study Description

This is a Phase II, open-label study evaluating the efficacy and safety of combined treatment (retinoic acid) with immune checkpoint inhibitors in metastatic HER2-negative breast cancer patients who progressed during or following previous immune checkpoint inhibitors. HER2-negative breast cancers include luminal breast cancers and triple-negative breast cancers.

Current clinical studies on immunotherapy for luminal breast cancer are limited, with inconsistent results across trials. The KEYNOTE-028 study reported an objective response rate (ORR) of only 12% for pembrolizumab in PD-L1-positive, previously treated advanced luminal breast cancer patients, demonstrating limited efficacy. The GIADA phase II trial revealed a pathological complete response (pCR) rate of 16.3% with neoadjuvant chemotherapy followed by immunotherapy in luminal breast cancer. Additionally, trials such as NCT02779751 and NCT03051659 also indicated limited clinical benefits from immunotherapy. However, the I-SPY2 platform showed that combinations like olaparib, paclitaxel, and immunotherapy or wP-AC chemotherapy with immunotherapy could improve pCR rates in high-risk patients. Despite advancements, immunotherapy benefits are limited in luminal breast cancer compared to other cancers, with advanced-stage patients more likely to develop resistance.

Recent clinical studies on advanced triple-negative breast cancer have shown that immunotherapy combined with chemotherapy demonstrates superior clinical efficacy compared to traditional chemotherapy alone. Phase III trials such as IMPassion130 and Keynote-522 have confirmed that PD-1/PD-L1 inhibitors used with chemotherapy significantly improve progression-free survival, overall survival, and pathological complete response rates. However, compared to other malignancies, triple-negative breast cancer patients still show relatively low overall response rates to immunotherapy: treatment-naïve patients achieve objective response rates of only 10-20% with immunotherapy monotherapy, though this improves to 56% when combined with chemotherapy, extending median progression-free survival to 7.2 months. Unfortunately, efficacy decreases significantly in later treatment lines, with objective response rates falling to just 10.6-15.9% after multiple previous treatments. Thus, strategies to overcome immunotherapy resistance or increase the sensitivity of immunotherapy efficacy are urgently needed for HER2-negative breast cancer patients.

The preclinical results of our center show that retinoic acid can enhance the anti-tumor immune response by promoting the peroxidation of macrophages, increasing the infiltration and function of cytotoxic CD8+ T cells, inhibiting the growth of tumors in mice. Based on the preclinical study, the investigators designed this study to enroll metastatic HER2-negative breast cancer patients who have progressed during or following immunotherapy, and to explore the efficacy of retinoic acid combined with immunotherapy at a clinical level, providing new strategies of combined treatment for HER2-negative breast cancer patients.

Connect with a study center

Fudan University Shanghai Cancer Center
Shanghai, Shanghai 200032
China
Site Not Available
Fudan University Shanghai Cancer Center
Shanghai 1796236, Shanghai Municipality 1796231 200032
China
Active - Recruiting

Not the study for you?

Let us help you find the best match. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.