This study will be conducted as an open label, single centre, Phase I study of PI3K (phosphatidyl inositol 3 kinase) inhibitor BAY80-6946 in Japanese patients with advanced or refractory solid tumours. The eligible subjects will be dosed intravenously at Day 1, Day 8 and Day 15 with three weeks on and one week off in each treatment cycle.

Inclusion Criteria:

• Cancer patients
• Japanese patients, who are at least 20 years of age
• Histological or cytological documentation of non-hematologic, malignant solid tumours, excluding primary brain or spinal tumours, with no past or current involvement in the central nervous system (CNS)
• At least one measurable lesion or evaluable disease according to RECIST (version 1.1)
• Eastern Cooperative Oncology performance status (ECOG-PS) of 0 or 1
• Life expectancy of at least 12 weeks
• Advanced or refractory solid tumours not amenable to standard therapy, at the first screening examination/visit

Exclusion Criteria:

• Anticancer chemotherapy or immunotherapy during the study or within 4 weeks of first study treatment. Patients must have recovered from the toxic effects of the previous anti-cancer chemotherapy or immunotherapy by the investigator (with the exception of alopecia).
• Radiotherapy to target lesions during study or within 4 weeks of first study treatment
• Investigational drug therapy outside of this trial during or within 4 weeks of first study treatment
• Current diagnosis of Type I or II diabetes mellitus or fasting blood glucose level >125 mg/dL at screening, and/or HbA1c>/= 6.5%
• Past and current histories of cardiac disease congestive heart failure > New York Heart Association (NYHA) Class II; active coronary artery disease, myocardial infarction within 6 months prior to study entry; new onset of angina within 3 months prior to study entry or unstable angina or ventricular cardiac arrhythmias requiring anti-arrhythmic therapy
• Active and clinically serious infections >Grade 2 (National Cancer Institute Common Terminology Criteria for Adverse Events [NCI-CTCAE] version 4.03)
• Uncontrolled hypertension defined as systolic blood pressure >150 mm Hg or diastolic pressure > 90 mm Hg, despite optimal medical management
• Patients undergoing renal dialysis
• Pregnant or breast feeding women