Activity and Safety Study of BKM120 in Monotherapy in Patient With Metastatic Head and Neck Cancer Recurrent or Progressive

Inclusion Criteria: * 1\. Adult men and women ≥ 18 years at the day of inform consent signature. * 2\. Patients with metastatic or relapsed squamous cell head and neck carcinoma . * 3\. Documented progression or relapse after platin and cetuximab or anti-epidermal growth factor receptor (EGFR) -based chemotherapy at time of study drug start * 4\. Documented mutational status of PIK3CA before study drug start * 5\. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 . * 6\. At least one measurable lesion by CT-scan as per RECIST 1.1 . * 7\. Life expectancy \> 12 weeks. * 8\. Patients must be able to swallow capsules. * 9\. Adequate bone marrow, renal and liver function as defined by the following tests : * Absolute neutrophil count ≥ 1.0 x 109/L, * Platelet count \> 100 x 109/L, * Haemoglobin value above 9 g/dL, * international normalized ratio (INR) ≤ 1.5 * Serum Creatinine ≤ 1.5 upper limit of normal (ULN) * Glomerular filtration rate calculated using Cockcroft-Gault formula \> 60ml/min (or MDRD formula for patients older than 65 years) * Potassium, calcium, magnesium within normal limits for the institution * Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) \< ULN (or \< 3.0 x ULN if liver metastases are present)) * Serum bilirubin within normal range (or ≤ 1.5 ULN if liver metastases are present; or total bilirubin ≤ 3.0 ULN with direct bilirubin within normal range in patients with well documented Gilbert Syndrome) * Fasting plasma glucose (FPG) ≤ 120 mg/dL or ≤ 6.7 mmol/L. * 10\. Women of childbearing potential (entering the study after a confirmed menstrual period and who have a negative pregnancy test within ≤ 72 hours before initiating study treatment) must agree to use two methods of medically acceptable forms of contraception during the whole treatment period and for 1 month (= 5 x t½ of BKM120) after the last treatment intake. * 11\. Fertile males must use a highly effective contraception during dosing of any study agent + \[5 x t1/2\] + 12 weeks = contraception through 16 weeks after final dose of study therapy and should not father a child in this period. Female partner of male study subject: highly effective contraception during dosing of study agent + 4 weeks after final dose of study therapy * 12\. Patient should be able and willing to comply with study visits and procedures as per protocol. * 13\. Patient should understand, sign, and date the written voluntary informed consent form at the screening visit prior to any protocol-specific procedures performed. * 14\. Patients must be covered by a medical insurance. Exclusion Criteria: * 1\. Patient having received previous treatment with PI3K and/or mammilian target of rapamycin (mTOR) inhibitors. * 2\. Patient with symptomatic central nervous system (CNS) metastases. * 3\. Patient with a concurrent malignancy or has a malignancy within 3 years of study enrollment, (with the exception of adequately treated basal or squamous cell carcinoma or non-melanomatous skin cancer). * 4\. Patient has any of the following mood disorders as judged by the Investigator or a Psychiatrist: * 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 (immediate risk of doing harm to others), * Patients with active severe personality disorders (defined according to Diagnostic and Statistical Manual (DSM) - IV) are not eligible. Note: for patients with psychotropic treatments ongoing at baseline, the dose and the schedule should not be modified within the previous 6 weeks prior to start of study drug. * ≥ CTCAE grade 3 anxiety, * or meets the cut-off score of ≥ 12 in the Patient Health Questionnaire (PHQ) -9 or a cut-off of ≥ 15 in the generalized anxiety disorder (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). * 5\. Patient concurrently using other approved or investigational anti-neoplasic agent. * 6\. Patient who has received anticancer therapy \< 2 weeks or investigational treatment \< 4 weeks prior the initiation of study drug. * 7\. Patient who has received radiotherapy ≤ 4 weeks prior to starting study drug or who have not recovered to grade 1 or better from related side effects of such therapy (exceptions include alopecia). * 8\. Patient having had major surgery within 14 days prior to starting study drug or has not recovered from major side effects of the surgery. * 9\. Patient with poorly controlled diabetes mellitus (i.e. HbA1c \> 8 %) * 10\. Patient with active cardiac disease including any of the following: * Left Ventricular Ejection Fraction (LVEF) \< 50% as determined by Multiple Gated acquisition (MUGA) scan or echocardiogram (ECHO), * corrected QT interval (QTc) \> 480 (female) or 470 msec (male) on screening ECG (using the corrected QT Fridericia (QTcF) formulae), * 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. * 11\. Patient with a 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, * History of documented congestive heart failure (New York Heart Association functional classification III-IV), * Documented cardiomyopathy, * Other cardiac arrhythmia not controlled with medication. * 12\. Patient currently receiving treatment with QT prolonging medication known to have a risk to induce Torsades de Pointes, and if the treatment cannot be discontinued or switched to a different medication prior to starting study drug. * 13\. Patient with impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of BKM120 * 14\. Patient receiving chronic treatment (\> 5 days) with steroids or another immunosuppressive agent. Note: Topical applications (e.g., rash), inhaled sprays (e.g., obstructive airways diseases), eye drops or local injections (e.g., intra-articular) are allowed. Patients with previously treated brain metastases, who are on a stable low dose corticosteroids treatment (e.g., dexamethasone 2 mg/day, prednisolone 10 mg/day) for at least 14 days before start of study treatment, are eligible. * 15\. Patient has other concurrent severe and/or uncontrolled medical condition that would, in the investigator's judgment contraindicate her participation in the clinical study * 16\. Patient has a history of non-compliance to medical regimen. * 17\. Patient is currently being treated with drugs known to be strong inhibitors or inducers of isoenzyme Cytochrome P450 family 3 subfamily A member 4 (CYP3A), and the treatment cannot be discontinued or switched to a different medication prior to starting study drug. * 18\. Patient has a known history of HIV infection. * 19\. Pregnant or nursing (lactating) woman. * 20\. Patient has a known hypersensitivity to any of the excipients of BKM120. * 21\. Patient has not recovered to grade 1 or better (except alopecia) from related side effects of any prior antineoplastic therapy. * 22\. Patient is currently receiving warfarin or other coumarin derived anti-coagulant, for treatment, prophylaxis or otherwise. Therapy with heparin, low molecular weight heparin, or fondaparinux is allowed. * 23\. Patient has acute viral hepatitis or a history of chronic or active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, typically defined by elevated AST/ALT (persistent or intermittent), high HBV DNA level, HBsAg positive, or high HCV RNA level (testing not mandatory)