Inclusion Criteria:

Primary Study Subjects (Consent A) Inclusion Criteria for Observation

- Patient must be 18 years of age or older

- Patients must have histologically confirmed (by routine H&E staining) adenocarcinoma
of the breast.

- Patients must have an axillary nodal evaluation either by FNA or SNB in accordance
with their institutional guidelines.

- Patients with squamous, or metaplastic carcinomas or sarcomas of the breast are NOT
eligible

- Patient must have a history and physical within 8 weeks prior to the start of any
protocol therapy

- Patient must have had a bilateral mammogram prior to surgery unless there is only one
breast.

- Patient must have a Medical Oncology consult and be recommended to receive
neoadjuvant chemotherapy for a stage II through IV carcinoma.

- Patients must have a performance status 0 or 1 by ECOG criteria (Appendix)

- Patients must not have received prior radiation therapy to the involved breast at any
time for any reason.

Secondary Study Subjects (Consent B) Inclusion Criteria for Treatment with Veliparib and
Radiation

- Patient must have > 1.0 cm residual in-breast cancer and/or clinically positive
residual nodal disease.

- Hematology:

Absolute Neutrophil Count (ANC) ≥ 1000/mm3 Platelet Count ≥ 100,000/mm3 Hemoglobin
≥ 9.0 g/dL (after transfusion if required)

- Renal Function: Creatinine Serum ≤ 2.0 mg/dl or Creatinine Clearance ≥45mL/min

- Hepatic Function: Bilirubin ≤ 1.5 mg/dL (≤ 3.0 mg/dL with liver metastasis) Serum
Glutamic-Oxaloacetic Transaminase (SGOT) ≤ 2.5 × ULN (≤ 5.0 × ULN with liver metastasis)
Serum Glutamic-Pyruvic Transaminase (SGPT) ≤ 2.5 × ULN (≤ 5.0 × ULN with liver
metastasis) ULN = Upper normal limit of institution's normal range

1. If calculated creatinine clearance is < 45 mL/min, a 24-hour urine collection for
creatinine clearance may be performed.

2. Subjects with Gilbert's disease may have bilirubin up to 2.5 mg/dL (or 3.0 mg/dL with
liver ( metastasis).

- Patients must not be pregnant due to the potential for fetal harm as a result of
this treatment regimen. Women of child-bearing potential must also have a
negative pregnancy test within six weeks prior to start of protocol therapy.

- No other prior malignancy is allowed except for adequately treated basal cell or
squamous cell skin cancer, in situ cervical cancer, or any other cancer from
which the patient has been disease-free for 5 years.

- Women of childbearing potential must agree to use adequate contraception (one of
the following listed below) prior to study entry, for the duration of study
participation and up to 2 months following completion of protocol therapy

a. Total abstinence from sexual intercourse (minimum one complete menstrual cycle) b. A
vasectomized partner c. Hormonal contraceptives (oral, parenteral or transdermal) for at
least 3 months prior to study drug administration d. Double-barrier metho (condoms,
contraceptive sponge, diaphragm or vaginal ring with spermicidal jellies or cream)

- Patients must not have a serious medical or psychiatric illness which prevents
informed consent or compliance with treatment.

- All patients must be informed of the investigational nature of this study and given
written informed consent in accordance with institutional and federal guidelines.

Exclusion Criteria:

- Women who were cT1-2 and cN0 before NAC and already planned to have a mastectomy.
(This group would likely not receive radiation standardly)

- Last dose of chemotherapy, immunotherapy, biologic therapy, or investigational
therapy, was less than 14 days prior to enrollment on POPI.

- Bisphosphonates, hormone modification therapy, and trastuzumab are permitted without
restriction.

- Unresolved or unstable, serious toxicity from prior administration of another
investigational drug and/or prior anti-cancer treatment.

- If female, subject is pregnant or breast-feeding

- Clinically significant and uncontrolled major cardiac, respiratory, renal, hepatic,
gastrointestinal, hematologic or neurological/psychiatric disease or
disorder,including but not limited to:

1. active uncontrolled infection

2. symptomatic congestive heart failure, unstable angina pectoris, or cardiac
arrhythmia

3. any other illness condition(s) that could exacerbate potential toxicities,
confound safety assessments, require excluded therapy for management, or limit
compliance with study requirements. Questions regarding inclusion of individual
subjects should be directed to the PI.

- Unable to swallow and retain oral medications.

- Known contraindication to enhanced MRI and CT, including but not limited to:

1. Presence of metal objects within the body such as a cardiac pacemaker, implanted
cardiac defibrillator, brain aneurysm clips, cochlear implant, ocular foreign
body, or shrapnel.

2. History of immediate or delayed hypersensitivity reaction or other
contraindication to contrast agents including but not limited to gadolinium and
iodine.

- Previous enrollment in this study or another study involving the investigation of
Veliparib (ABT-888), with the exception of receiving a single dose of study drug.

- Consideration by the Investigator, for any reason, that the subject is an unsuitable
candidate to receive Veliparib (ABT-888) and/or breast irradiation.

- For purposes of this protocol, anti-tumor treatment may be defined as, but is not
limited to, anti-cancer agents (cytotoxic chemotherapy, immunotherapy, biologic
therapy), radiotherapy, and investigational agents. An investigational agent is any
drug or therapy not currently approved for use in humans.

NOTE:

- Anti-cancer Agents: Anti-cancer agents are not permitted within 14 days prior to
start of POPI. There are no limitations on the type or number of prior regimens.

- Radiation: Prior treatment with breast irradiation is not allowed due to the
potential for cumulative toxicities.

- Surgery: Incident breast biopsies only permitted prior to POPI to confirm residual
disease after NAC.