Ann Arbor Stage IV Grade 1 Follicular Lymphoma

This phase II trial studies how well acalabrutinib, lenalidomide, and rituximab work in treating patients with CD20 positive stage III-IV, grade 1-3a follicular lymphoma. Acalabrutinib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Drugs used in chemotherapy, such as lenalidomide, 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. Rituximab is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Giving acalabrutinib, lenalidomide, and rituximab may help to control the disease.