Inclusion Criteria:

- Pathologically and radiologically confirmed metastatic TNBC (Stage IV disease),
previously documented by histological analysis, which is ER-negative and PR-negative
by IHC and HER2 negative by IHC or FISH/CISH.

- Subjects must have received at least two prior neoadjuvant chemotherapy regimens,
adjuvant or metastatic

- Availability of a representative tumor specimen (primary or metastasis, archival
tissue or fresh biopsy for patients with biopsiable tumor) at baseline.

- At least one measurable lesion by RECIST 1.1

- Age ≥ 18 years at the day of consenting to the study

- ECOG performance status ≤ 2

- Adequate bone marrow and organ function as defined by the following laboratory
values:

ANC ≥ 1.0 x 109/L, platelets ≥ 100 x 109/L, hemoglobin ≥ 9.0 g/dL, INR ≤ 2; potassium,
calcium, magnesium within normal limits for the institution; serum creatinine ≤ 1.5 x ULN,
ALT and AST within normal range (or ≤ 3.0 x ULN if liver metastases are present); serum
bilirubin within normal range (or ≤ 1.5 x ULN if liver metastases are present; or total
bilirubin ≤ 3.0 x ULN with direct bilirubin within normal range in patients with well
documented Gilbert Syndrome); fasting plasma glucose (FPG) ≤ 140 mg/dL or ≤ 7.8 mmol/L.

Exclusion Criteria:

- Previous treatment with PI3K inhibitors

- Symptomatic CNS metastases

- Patients with controlled and asymptomatic CNS metastases may participate in this
trial. As such, the patient must have completed any prior treatment for CNS
metastases > 28 days (including radiotherapy and/or surgery) prior to enrollment in
this study. Patients with previously treated brain metastases, who are on a stable
low dose corticosteroids treatment are eligible.

- Concurrent malignancy or malignancy within 3 years of study enrollment (with the
exception of adequately treated basal or squamous cell carcinoma or non-melanomatous
skin cancer)

- Patients with documented germline mutations in BRCA1 or 2, who may have previous
history of cancer

- Any of the following mood disorders as judged by the Investigator or a Psychiatrist,
or meets the cut-off score of ≥ 10 in the PHQ-9 or a cut-off of ≥ 15 in the GAD-7
mood scale, respectively, or selects a positive response of '1, 2, or 3' to question
number 9 regarding potential for suicidal thoughts ideation in the PHQ-9 (independent
of the total score of the PHQ-9)

o Medically documented history of or active major depressive episode, bipolar
disorder (I or II), obsessive-compulsive disorder, schizophrenia, a history of
suicidal attempt or ideation, or homicidal ideation. CTCAE v 4.0 ≥ grade 3 anxiety

- Concurrent use of other approved or investigational antineoplastic agent and/or
chemotherapy ≤ 21 days before study accrual

- Radiotherapy ≤ 28 days prior to enrollment or failure to recover from side effects of
such therapy at the time of initiation of screening procedures.

- Major surgery within 28 days prior to starting study drug or has not recovered from
major side effects of the surgery

- Poorly controlled diabetes mellitus (HbA1c > 8%)

- Active cardiac disease including any of the following:

- Left Ventricular Ejection Fraction (LVEF) < 50% by MUGA scan or ECHO QTc > 480
msec on screening ECG (using the QTcF formula

- Angina pectoris that requires the use of anti-anginal medication

- Ventricular arrhythmias except for benign premature ventricular contractions

- Supraventricular and nodal arrythmias requiring a pacemaker or not controlled
with medication

- Conduction abnormality requiring a pacemaker

- Valvular disease with documented compromise in cardiac function

- Symptomatic pericarditis

- History of cardiac dysfunction including any of the following;

- Myocardial infarction within the last 6 months, documented by persistent
elevated cardiac enzymes or persistent regional wall abnormalities on assessment
of LVEF function

- Congestive heart failure (New York Heart Association functional classification
III-IV)

- Cardiomyopathy

- Treatment with QT prolonging medication known to have a risk to induce Torsades de
Pointes

- Impairment of GI function or GI disease that may significantly alter the absorption
of BKM120

- Chronic treatment with immunosuppressive agent. Note: Topical applications, inhaled
sprays, eye drops or local injections are allowed. Patients with who are on a stable
low dose corticosteroids treatment for their brain metastases for at least 14 days
before start of study treatment, are eligible

- Other concurrent severe and/or uncontrolled medical condition that would, in the
investigator's judgment, contraindicate participation

- Current treatment with drugs known to be moderate or strong inhibitors or inducers of
isoenzyme CYP3A

- HIV infection

- Pregnant or nursing

- Woman of child-bearing potential unwilling to use acceptable methods of contraception