Idelalisib in Treating Participants with Indolent or Transformed Indolent Non-Hodgkin Lymphoma after Autologous Stem Cell Transplant

Inclusion Criteria

• Histologically documented (by history of present illness [HPI] or pathology report) iNHL as defined by follicular lymphoma (FL), marginal zone lymphoma (MZL), lymphoplasmacytic lymphoma/Waldenstrom disease (LPL/WM) and small lymphocytic lymphoma (SLL) or tiNHL as defined by large B cell transformation of any of the above entities including chronic lymphocytic leukemia (CLL)
• Patients must be eligible to undergo high dose chemotherapy (HDT) followed by ASCT as a form of remission consolidation
• Patients without evidence of documented disease progression clinically or radiographically after ASCT (stable disease [SD], partial remission [PR] or complete remission [CR]) who have had count recovery (absolute neutrophil count [ANC] > 500 cells/mm^3, non-transfused platelet count > 20,000 K/mm^3) and are at least 30 days post ASCT but no more than 120 days post ASCT
• Patients may have received any prior therapy deemed necessary for them to be eligible to HDT/ASCT except for patients whom have progressed while on Zydelig. Patients who have responded to Zydelig previously are eligible for enrollment on the protocol
• Eastern Cooperative Oncology Group (ECOG) performance status < 4
• Life expectancy of greater than four months
• Total bilirubin =< 2 x institutional upper limit of normal (ULN) (after the HDT/ASCT)
• Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase [SGOT])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) < 2.5 x institutional upper limit of normal (after the HDT/ASCT)
• Creatinine =< 1.5 x institutional upper limit of normal OR creatinine clearance >= 60 mL/min/1.73 m^2 for patients with creatinine levels >= 1.5 x upper limit of normal (after the HDT/ASCT)
• Because the effects of zydelig on the developing human fetus are unknown, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. Female subjects of childbearing potential should have a negative pregnancy test within 72 hours prior to receiving the first dose of zydelig. Male subjects must agree to use an adequate method of contraception starting with the first dose of the study drug Zydelig. Female and male participants must agree to use contraception for at least 30 days after the last dose of Zydelig. Women of childbearing potential is defined as women who continues to have menstrual periods, have not had a tubal ligation, or the removal of fallopian tubes, ovaries or uterus.
• Ability to understand English and the willingness to sign a written informed consent document

Exclusion Criteria

• Patients who have had chemotherapy or radiotherapy within 2 weeks of first dose of zydelig
• Patients receiving any other investigational agents within 30 days of receiving zydelig
• Patients who were previously exposed to zydelig and experienced progression of disease
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to zydelig
• Patients with active and/or untreated central nervous system (CNS) lymphoma will not be eligible
• Patients with inflammatory bowel disease
• Uncontrolled intercurrent illness including, but not limited to ongoing or active infection (defined as requiring systemic antibiotic treatment and fever within 48 hours of screening), symptomatic congestive heart failure (patients with New York Health Association [NYHA] score of III and above are excluded), unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• Women who are pregnant or nursing or plan to become pregnant or nurse during the course of the study
• Positive human immunodeficiency virus (HIV) status
• Patients with lack of count recovery as defined by ANC > 500 cells/mm^3, non-transfused platelet count > 20,000 K/mm^3
• Patients who are unable to swallow pills
• Patients with moderate to severe lung disease including: * Patients requiring oxygen (O2) supplementation * Patients unable to walk 50 feet without stopping to rest ** Obstructive lung disease as defined by pre-transplant forced expiratory volume in one second (FEV1) =< 60% of predicted ** Restrictive lung disease as defined by pre-transplant forced vital capacity (FVC) < 60% of predicted
• Patients taking strong CYP3A4 inhibitors or inducers with risk X (avoid combination) according to lexicomp
• Patients with active hepatic disease, liver cirrhosis, or known hepatitis B virus (HBV)/hepatitis C virus (HCV) infection
• Patients with de novo diffuse large B-cell lymphoma
• Patients with history of (h/o) pneumocystis pneumonia (PCP) or positive cytomegalovirus (CMV) viremia confirmed twice at least 1 day apart at screening