This is an umbrella study evaluating the efficacy and safety of multiple treatment combinations in participants with metastatic or inoperable locally advanced breast cancer.

The study will be performed in two stages. During Stage 1, six cohorts will be enrolled in parallel in this study:

Cohort 1 will consist of programmed death-ligand 1 (PD-L1)-positive participants who have received no prior systemic therapy for metastatic or inoperable locally advanced triple-negative breast cancer (TNBC) (first-line \[1L\] PD-L1+ cohort).

Cohort 2 will consist of participants who had disease progression during or following 1L treatment with chemotherapy for metastatic or inoperable locally-advanced TNBC and have not received cancer immunotherapy (CIT) (second-line \[2L\] CIT-nave cohort).

Cohort 3, 5, and 6 will consist of participants with locally advanced or metastatic hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative disease with one or more PIK3CA mutations.

Cohort 4 will consist of participants with locally advanced or metastatic HER2+ /HER2-low disease with one or more PIK3CA mutations who had disease progression on standard-of-care therapies (HER2+ /HER2-low cohort).

In each cohort, eligible participants will initially be assigned to one of several treatment arms (Stage 1). During Stage 2, participants in the 2L CIT-nave cohort who experience disease progression, loss of clinical benefit, or unacceptable toxicity during Stage 1 may be eligible to continue treatment with a different treatment combination, provided Stage 2 is open for enrollment and all eligibility criteria are met.

The goal of this clinical trial is to evaluate the safety of TOS-358 in adults with select solid tumors who meet study enrollment criteria. The main questions it aims to answer are:

1. what is the maximum tolerated dose and recommended dose for phase 2?
2. how safe and tolerable is TOS-358 at different dose levels when taken orally once or twice per day?

This is a multicenter, Phase 1b/2 trial in participants with estrogen receptor positive/human epidermal growth factor receptor 2 negative (ER+/HER2-) advanced/metastatic breast cancer. The phase 1b part of the trial will determine the recommended Phase 2 dose (RP2D) of elacestrant when administered in combination with alpelisib, everolimus, palbociclib, capivasertib, and ribociclib. The Phase 2 part of the trial will evaluate the efficacy and safety of the various combinations.

The goal of this trial is to see if active surveillance monitoring and hormonal therapy in patients diagnosed with ductal cell carcinoma in situ (DCIS), an early stage of breast cancer, can be an effective management of the disease.

Participants will be asked to receive control hormonal therapy or an investigational hormonal therapy treatment. Participants will be asked to return for evaluation with MRI at three months and six months. Depending on the evaluation participants will have the option to continue on the treatment. If the evaluation suggests surgery is recommended, the participant will discontinue the study treatment and will undergo surgery. In addition to the treatment and MRI evaluation, participants will be asked to provide blood sample to understand their immune status, provide saliva sample for genetic testing, provide the study with a portion of the tissue or slides generated from tissue removed during surgery performed as part of their standard of care.

This Phase III Trial evaluates whether breast conservation surgery and endocrine therapy results in a non-inferior rate of invasive or non-invasive ipsilateral breast tumor recurrence (IBTR) compared to breast conservation with breast radiation and endocrine therapy.

This phase II trial compares the effect of adding darolutamide to standard therapy versus standard therapy alone before surgery for the treatment of patients with stage II-IIIA androgen receptor positive triple-negative breast carcinoma. Standard therapy before surgery for triple-negative breast cancer typically consists of a combination of chemotherapy and immunotherapy drugs. Chemotherapy drugs, such as carboplatin, paclitaxel, doxorubicin and cyclophosphamide, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Darolutamide is in a class of medications called androgen receptor inhibitors. It works by blocking the effects of androgen (a male reproductive hormone) to stop the growth and spread of tumor cells. Giving darolutamide in combination with standard therapy before surgery may make the tumor smaller and may reduce the amount of normal tissue that needs to be removed.

This phase II trial studies how well the combination of avelumab with liposomal doxorubicin with or without binimetinib, or the combination of avelumab with sacituzumab govitecan works in treating patients with triple negative breast cancer that is stage IV or is not able to be removed by surgery (unresectable) and has come back (recurrent). Immunotherapy with checkpoint inhibitors like avelumab require activation of the patient's immune system.

This trial includes a two week induction or lead-in of medications that can stimulate the immune system. It is our hope that this induction will improve the response to immunotherapy with avelumab. One treatment, sacituzumab Govitecan, is a monoclonal antibody called sacituzumab linked to a chemotherapy drug called SN-38. Sacituzumab govitecan is a form of targeted therapy because it attaches to specific molecules (receptors) on the surface of tumor cells, known as Tumor-associated calcium signal transducer 2 (TROP2) receptors, and delivers SN-38 to kill them. Another treatment, liposomal doxorubicin, is a form of the anticancer drug doxorubicin that is contained in very tiny, fat-like particles. It may have fewer side effects and work better than doxorubicin, and may enhance factors associated with immune response. The third medication is called binimetinib, which may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth, and may help activate the immune system. It is not yet known whether giving avelumab in combination with liposomal doxorubicin with or without binimetinib, or the combination of avelumab with sacituzumab govitecan will work better in treating patients with triple negative breast cancer.

The purpose of this study is to determine if a combination of two drugs sacituzumab govitecan and atezolizumab works as a treatment for residual cancer in the breast or lymph nodes and have circulating tumor DNA in the blood.

This research study involves the following investigational drugs:

* Sacituzumab govitecan
* Atezolizumab

An Open-label, Phase I Dose Escalation and Phase 2 Dose Expansion Study to Assess Safety, Tolerability, Preliminary Antitumor Activity of SMP 3124LP in Adults with Advanced Solid Tumors

This open-label research study is studying (Z)-endoxifen as a possible treatment for pre-menopausal women with ER+/HER2- breast cancer. (Z)-endoxifen belongs to a group of drugs called selective estrogen receptor modulators or "SERM", which help block estrogen from attaching to cancer cells. This study has two parts: a pharmacokinetic part and a treatment part.

The PK part (how the body processes the drug) will enroll about 18 participants. All participants will take (Z)-endoxifen capsules daily. Twelve participants will be randomly assigned (50/50 chance) to take (Z)-endoxifen alone or (Z)-endoxifen with a monthly injection of goserelin a drug that temporarily stops the ovaries from making estrogen. This part will help determine the best dose of (Z)-endoxifen by measuring the drug levels in the blood and how long the body takes to remove it.

The Treatment Cohort has been simplified to a single study arm (Z)-endoxifen + goserelin. Up to 20 participants will be enrolled that have a baseline Ki-67 10% and 45 participants will be enrolled that have a baseline Ki-67\>10%.

A key goal of the study is to see if (Z)-endoxifen can slow down or stop tumor growth as measured by a reduction in Ki-67 levels. Tumor tissue samples will be taken by breast biopsy after about 4 weeks of treatment to check levels of this biomarker. If the tumor shows signs of response, participants can continue treatment for up to 24 weeks or until they have surgery.

Study participation is up to 6 months (24 weeks of treatment) followed by surgery and a one-month follow up visit.