Inclusion Criteria:

          -  ≥18 y/o (no upper age limit)

          -  ECOG PS ≤2

          -  Disease - Histologically or cytologically documented newly diagnosed (stages II, III
             or IV) Myc-positive DLBCL, transformed follicular lymphoma, or high-grade
             unclassifiable with features intermediate between DLBCL and Burkitt lymphoma

          -  Myc Positive lymphoma is defined by:

               -  Positive for Myc gene rearrangement by fluorescence in-situ hybridization (FISH)
                  involving various breakpoints (e.g. 8-14, 8-22 and 2-8) AND concurrent gene
                  rearrangements in bcl-2 and/or bcl-6 by FISH OR

               -  Myc and Bcl-2 overexpression defined by > 40% Myc and > 70% Bcl-2 expression by
                  IHC. Patients may enroll in the study based on the local laboratory evaluation,
                  but these should be confirmed by the UNC Hematopathology Laboratory
                  retrospectively

          -  Positive for CD20 via immunophenotyping

          -  Prior Treatment: Previously untreated or who received a maximum of one cycle of
             combination chemotherapy (i.e. R-CHOP, R-EPOCH, or R-hyperCVAD) within 4 weeks of
             study entry except patients who require dose reduction after the first cycle of
             off-study R-EPOCH.

          -  Measurable disease as assessed by 2 dimensional measurements by CT (≥ 1.5 cm).

          -  Adequate organ function as demonstrated by:

               -  Bone marrow function (without platelet transfusion or myeloid growth factor
                  support within two weeks of screening) as demonstrated by:

               -  Hemoglobin ≥ 8 g/dL

               -  Absolute neutrophil count (ANC) ≥ 1,000 cells/mm3

               -  Platelet count ≥75,000/mm3

          -  And hepatic and renal function as demonstrated by:

               -  Aspartate aminotransferase (AST) and Alanine Aminotransferase (ALT) ≤2.5 x upper
                  limit of normal (ULN); ALT and AST up to 5 x ULN if liver metastases present

               -  Total serum bilirubin ≤1.5 x ULN

               -  Serum creatinine ≤1.5 x ULN or CrCl of ≥ 30

          -  Adequate renal function as defined by: Calculated creatinine clearance must be ≥ 30
             mL/minute based on Cockcroft-Gault formula

          -  Documented negative serologic testing for human immunodeficiency virus (HIV),
             hepatitis B (unless serologically positive due to prior vaccination), and hepatitis C
             within the year prior to enrollment (note: for guidance in defining active infection
             for hepatitis B, please refer to the WHO guidelines. (World Health Organization,
             Global Alert and Response (GAR), Hepatitis B (who.int/csr/disease/hepatitis/
             whocdscsrlyo20022/en/index4.html)

          -  Patient agrees to consume no more than 1 standard unit of alcohol per day during the
             study and for 30 days from the last dose of alisertib. A standard unit of alcohol is
             defined as a 12 oz beer (350 mL), 1.5 oz (45 mL) of 80-proof alcohol, or one 6-oz (175
             mL) glass of wine.

          -  Women of childbearing potential (WOCBP) must have negative pregnancy test within 7
             days prior to D1 of treatment

          -  Female subjects must be:

               -  Post-menopausal for at least one year before the screening visit, or

               -  Surgically sterilized, or

               -  Willing to use an acceptable method of birth control (ie, a hormonal
                  contraceptive, intra-uterine device, diaphragm with spermicide, condom with
                  spermicide, or abstinence) for the duration of the study.

          -  Male subject, even if surgically sterilized (ie, status post-vasectomy), agrees to:

               -  Use an acceptable method for contraception (effective barrier contraception or:

               -  Completely abstain from heterosexual intercourse) during the entire study
                  treatment period through 4 months after the last dose of alisertib.

          -  Ability to swallow oral medications

          -  As determined by the enrolling physician or protocol designee, ability of the patient
             to understand and comply with study procedures for the entire length of the study

          -  Sufficient data to calculate the International Prognostic Index (IPI) score at
             baseline:

               -  Age

               -  Stage of Disease

               -  LDH

               -  ECOG performance status

               -  number of extranodal sites

          -  Voluntary written informed consent before performance of any study-related procedure
             not part of normal medical care, with the understanding that consent may be withdrawn
             by the subject at any time without prejudice to future medical care.

          -  Adequate left ventricular function with ejection fraction ≥ 40% by echocardiogram or
             MUGA scan.

        Exclusion Criteria

          -  CNS involvement of DLBCL

          -  Major surgery within 4 weeks prior to entry

          -  Receiving any other concurrent cytotoxic, biologic agent(s) or investigational agent ;
             NOTE: Concurrent intrathecal chemotherapy for CNS prophylaxis allowed per
             institutional standards

          -  Receipt of investigational drugs within 14 days before D1 of alisertib

          -  Prior administration of an Aurora A kinase-targeted agent, including alisertib

          -  Patients with a "currently active" second malignancy other than non-melanoma skin
             cancers, non-invasive bladder cancer, "low risk" adenocarcinoma of the prostate and
             carcinoma in situ of the cervix. Patients are not considered to have a "currently
             active" malignancy if they have completed therapy and are free of disease for ≥ 3
             years.

          -  Treatment with clinically significant enzyme inducers, such as the enzyme-inducing
             antiepileptic drugs phenytoin, carbamazepine or phenobarbital, or rifampin, rifabutin,
             rifapentine or St. John's wort within 14 days prior to the first dose of alisertib and
             during the study.

          -  Radiation therapy to more than 25% of the bone marrow (note: whole pelvic radiation is
             considered to be over 25%)

          -  Prior allogeneic bone marrow or organ transplantation

          -  Known GI disease or GI procedures that could interfere with the oral absorption or
             tolerance of alisertib; examples include, but are not limited to partial gastrectomy,
             history of small intestine surgery, and celiac disease

          -  Known history of uncontrolled sleep apnea syndrome and other conditions that could
             result in excessive daytime sleepiness, such as severe chronic obstructive pulmonary
             disease; requirement for supplemental oxygen

          -  Requirement for constant administration of proton pump inhibitor from 5 days prior to
             D1 of alisertib, and/or requirement for constant administration of H2 antagonist, or
             pancreatic enzymes; intermittent uses of antacids or H2 antagonists are allowed

          -  Requirement for drugs, juices and/or herbs strongly inhibit CYP3A4 from within 7 days
             prior to D1 of alisertib and throughout treatment NOTE: Glucocorticoids are considered
             inducers of CYP3A4. However, their use is allowed if patient has been taking a
             continuous dose of no more than 15 mg/day of prednisone (or its equivalent) for at
             least 1 month prior to D1 of alisertib. In addition, low dose steroid use for the
             control of nausea and vomiting will be allowed. Topical steroid use and inhaled
             steroids are also permitted.

          -  Systemic infection requiring IV antibiotic therapy within 14 days preceding the first
             dose of study drug, or other severe infection

          -  Myocardial infarction within 6 months prior to enrollment or has New York Heart
             Association (NYHA) Class III or IV heart failure, uncontrolled angina, severe
             uncontrolled ventricular arrhythmias, or electrocardiographic evidence of acute
             ischemia or active conduction system abnormalities. Prior to study entry, any ECG
             abnormality at Screening has to be documented by the investigator as not medically
             relevant.

          -  Female subject who is pregnant or breast-feeding; confirmation that the subject is not
             pregnant must be established by a negative serum beta-human chorionic gonadotropin
             (beta-hCG) pregnancy test result obtained during screening (within 7 days prior to D1
             of treatment). Pregnancy testing is not required for post-menopausal or surgically
             sterilized women.

          -  Serious medical or psychiatric illness likely to interfere with participation in this
             clinical study

          -  Other severe acute or chronic medical or psychiatric condition, including uncontrolled
             diabetes, malabsorption, resection of the pancreas or upper small bowel, requirement
             for pancreatic enzymes, any condition that would modify small bowel absorption of oral
             medications, or laboratory abnormality that may increase the risk associated with
             study participation or investigational product administration or may interfere with
             the interpretation of study results and, in the judgment of the investigator, would
             make the patient inappropriate for enrollment in this study.

          -  Inability to swallow oral medication or inability or unwillingness to comply with the
             administration requirements related to alisertib.

          -  Administration of myeloid growth factors or platelet transfusion within 14 days prior
             to the first dose of study treatment