This study will evaluate the safety, tolerability, and efficacy of Orca-T in participants undergoing reduced intensity or non-myeloablative allogeneic hematopoietic cell transplantation (alloHCT) for hematologic malignancies. Orca-T is an allogeneic stem cell and T-cell immunotherapy biologic manufactured for each patient (transplant recipient) from the mobilized peripheral blood of a specific, unique donor. It is composed of purified hematopoietic stem and progenitor cells (HSPCs), purified regulatory T cells (Tregs), and conventional T cells (Tcons).

This phase I/II trial studies the safety, side effects and best dose of M3814 and to see how well it works when given together with radiation therapy in treating patients with pancreatic cancer that has spread to nearby tissue or lymph nodes (locally advanced). M3814 may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Hypofractionated radiation therapy delivers higher doses of radiation therapy over a shorter period of time and may kill more tumor cells and have fewer side effects. Giving M3814 and hypofractionated radiation therapy together may be safe, tolerable and/or more effective than radiation therapy alone in treating patients with locally advanced pancreatic cancer.

This phase I/II trial studies the side effects, safety, and effectiveness of low dose radiation to the entire body (total body irradiation \[TBI\]) and higher dose radiation to known areas of cancer (hypofractionated radiation therapy \[H-RT\]) combined with atezolizumab and chemotherapy (carboplatin \& etoposide) in treating patients with small cell lung cancer that has spread to disease sites outside of the lung (extensive stage). Extensive stage disease has historically been treated with chemotherapy alone with consideration of chest (thoracic) radiation therapy for those with response to chemotherapy, as well as consideration of preventative radiation therapy to the head (prophylactic cranial irradiation). Emerging evidence supports the synergistic interactions between immunotherapy and radiation therapy. Immunotherapy with monoclonal antibodies, such as atezolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Carboplatin is in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping or slowing the growth of tumor cells. Etoposide is in a class of medications known as podophyllotoxin derivatives. It blocks a certain enzyme needed for cell division and DNA repair and may kill tumor cells. Combining TBI and H-RT with atezolizumab and chemotherapy may improve response to treatment.