This phase II trial studies how well stopping anti-HER2 therapy works in improving outcomes of patients with HER2-positive breast cancer that has spread from where it first started (primary site) to other places in the body (metastatic) and have experienced long-term benefit from first-line treatment (exceptional responders). Patients with metastatic HER2-positive breast cancer are currently treated with systemic drugs indefinitely. These drugs include chemotherapy and/or biological agents targeting the HER2 protein. The first drug combination administered after diagnosis of metastatic spread (i.e., first-line treatment) usually combines chemotherapy with anti-HER2 agents (trastuzumab with or without pertuzumab). Chemotherapy is administered for a limited number of months, and anti-HER2 agents are continued indefinitely as maintenance therapy. Some of these patients experience a long-term benefit from first-line treatment without cancer growth and can be defined as exceptional responders. Nevertheless, all patients with this type of tumor typically continue maintenance treatment with anti-HER2 therapy indefinitely. Exceptional responders usually receive treatment for many years. Information learned from this trial may help researchers understand whether maintenance anti-HER2 treatment can be safely stopped in patients with exceptional response to first-line therapy.

This phase II trial studies the effect of hormonal therapy given after (adjuvant) combination pertuzumab/trastuzumab in treating patients with hormone receptor positive, HER2 positive breast cancer. The drugs trastuzumab and pertuzumab are both monoclonal antibodies, which are disease-fighting proteins made by cloned immune cells. Estrogen can cause the growth of breast cancer cells. Hormonal therapy, such as letrozole, anastrozole, exemestane, and tamoxifen, block the use of estrogen by the tumor cells. Giving hormonal therapy after pertuzumab and trastuzumab may kill any remaining tumor cells in patients with breast cancer.

This phase II trial studies the effect of lutetium Lu 177 dotatate compared to the usual treatment (everolimus) in treating patients with somatostatin receptor positive bronchial neuroendocrine tumors that have spread to other places in the body (advanced). Radioactive drugs, such as lutetium Lu 177 dotatate, may carry radiation directly to tumor cells and may reduce harm to normal cells. Lutetium Lu 177 dotatate may be more effective than everolimus in shrinking or stabilizing advanced bronchial neuroendocrine tumors.

This phase II trial studies how well TPIV100 and sargramostim work in treating patients with HER2 positive, stage I-III breast cancer that has residual disease after chemotherapy prior to surgery. It also studies why some HER2 positive breast cancer patients respond better to chemotherapy in combination with trastuzumab and pertuzumab. TPIV100 is a type of vaccine made from HER2 peptide that may help the body build an effective immune response to kill tumor cells that express HER2. Sargramostim increases the number of white blood cells in the body following chemotherapy for certain types of cancer and is used to alert the immune system. It is not yet known if TPIV100 and sargramostim will work better in treating patients with HER2 positive, stage I-III breast cancer.

This phase I trial tests the safety, side effects, and best dose of ZEN003694 in combination with the usual treatment with capecitabine in treating patients with cancer that has spread from where it first started (primary site) to other places in the body (metastatic) or cannot be removed by surgery (unresectable) and that it has progressed on previous standard treatment. ZEN003694 is an inhibitor of a family of proteins called the bromodomain and extra-terminal (BET). It may prevent the growth of tumor cells that over produce BET protein. Capecitabine is in a class of medications called antimetabolites. It is taken up by cancer cells and breaks down into fluorouracil, a substance that kills cancer cells. Giving ZEN003694 in combination with capecitabine may be safe in treating patients with metastatic or unresectable solid tumors.

This study aims to determine the safety, pharmacokinetics (PK) and recommended Phase 3 dose
(RP3D) of RYZ101 in Part 1, and the safety, efficacy, and PK of RYZ101 compared with
investigator-selected standard of care (SoC) therapy in Part 2 in subjects with inoperable,
advanced, well-differentiated, somatostatin receptor expressing (SSTR+)
gastroenteropancreatic neuroendocrine tumors (GEP-NETs) that have progressed following
treatment with Lutetium 177-labelled somatostatin analogue (177Lu-SSA) therapy, such as
177Lu-DOTATATE or 177Lu-DOTATOC (177Lu-DOTATATE/TOC), or 177Lu-high affinity [HA]-DOTATATE.

The investigational drug to be studied in this protocol, BCA101, is a first-in-class compound
that targets both EGFR with TGF. Based on preclinical data, this bifunctional antibody may
exert synergistic activity in patients with EGFR-driven tumors.