HER2 Low Breast Carcinoma

The goal of this study is to evaluate the safety and efficacy of elacestrant in combination with trastuzumab deruxtecan (T-DXd) in participants with hormone receptor-positive (HR+), HER2-low or HER2-ultralow, metastatic breast cancer that is resistant to prior CDK4/6 inhibitor and endocrine therapy. The names of the study drugs involved in this study are: * Elacestrant (a type of selective estrogen receptor degrader) * Trastuzumab deruxtecan (a type of standard of care antibody drug conjugate)

This phase II trial tests how well ARX788 works in treating patients diagnosed with HER2-low, locally advanced unresectable or metastatic breast cancer. ARX788 is an antibody-drug conjugate (ADC) that is given by infusion (diluted and injected slowly into veins). Antibodies are proteins which are naturally produced by the body's immune system to help fight infections. ARX788 consists of antibodies that have been attached to a toxin that has the potential to kill cancer cells. ARX788 sticks to a protein called human epidermal growth factor receptor (HER2), which is found on some breast cancer cells. Giving ARX788 may be safe and effective in treating patients with HER2-low locally advanced unresectable metastatic breast cancer.

I-SPY Phase I/Ib (I-SPY-P1) is an open-label, multisite platform study designed to evaluate single agents or combinations in a metastatic treatment setting that may be relevant for breast cancer patients with the overall goal of moving promising drug regimens into the I-SPY 2 SMART Design Trial (NCT01042379) and/or other oncology-based trials in a timely manner.

HR-positive breast cancers accounts for about 50% to 60% of all breast cancer patients. Neoadjuvant Chemotherapy is the core treatment mode for this type of breast cancer, and endocrine therapy can be used in some low-risk patients. However, the pathological complete response (pCR) rate obtained is low. HER2 is an important prognostic indicator and therapeutic target for breast cancer. Nearly 60% of HR-positive breast cancers have low expression of HER2, and antibody-drug conjugates (ADC) targeting HER2 may achieve better efficacy in this subtype.

ICARUS-BREAST02 is an open-label, multicenter, phase 1b/2, platform study that aims to evaluate the safety, tolerability, and efficacy of HER3-DXd monotherapy and in combination with other anti-cancer agents in patients with ABC. The first 2 modules will evaluate: i. safety and efficacy of HER3-DXd with olaparib in patients with HER2-low and HER2-positive ABC progressed on T-DXd (Module 1) and HER3-DXd monotherapy in patients with HER2-low ABC progressed on T-DXd (Module 0). The main objective of Part 1 is to assess the safety and tolerability of HER3-DXd monotherapy and combination and to determine the recommended phase 2 dose (RP2D) of the combination containing HER3-DXd. The main objective of Part 2 is to assess the efficacy of study therapies in each module based on investigator assessment as evaluated by the objective response rate (ORR) at 6 months.