A Study of Nab-paclitaxel-based Doublet as First Line Therapy in Patients With Cancer of Unknown Primary (CUP)

Inclusion Criteria: * Provision of written informed consent. * Patients must be ≥ 18 years of age. * Diagnosis of CUP according to CUP Diagnostic Guidelines derived from ESMO 2011 and NCCN 2015 guidelines. * Sufficient archived biopsy tissue from a surgical or core needle biopsy required to perform the CUP multiplex assay. * Eastern Cooperative Oncology Group performance status ≤ 2. * No previous systemic therapy. * At least one measurable lesion by RECIST Criteria. * Good liver, cardiac, lung and marrow bone function. * Evidence of non-childbearing status for female patients: negative urine or serum pregnancy test within 21 days of study treatment for women of childbearing potential, or postmenopausal status. * Patients of child bearing potential and their partners, who are sexually active, must agree to the use of highly effective forms of contraception throughout their participation in the study. * Patient is willing and able to comply with the protocol for the duration of the study, including undergoing treatment and scheduled visits and examinations. Exclusion Criteria: * Patients with second primary cancer, except: adequately treated non-melanoma skin cancer, curatively treated in-situ cancer of the cervix, breast Ductal Carcinoma in Situ (DCIS), stage 1 grade 1 endometrial carcinoma. * Specific treatable CUP syndromes including: extragonadal germ cell syndrome; neuroendocrine carcinoma; adenocarcinoma isolated to axillary lymph nodes (women cancer); peritoneal carcinomatosis (women - ovarian cancer); squamous carcinoma limited to cervical, supraclavicular, or inguinal lymph nodes; single resectable metastasis. * Patients receiving any radiotherapy (except for palliative reasons), within 2 weeks from the last dose prior to study entry. * Patients with symptomatic uncontrolled brain metastases. * Major surgery within 2 weeks of starting the study and patients must have recovered from any effects of any major surgery. * Patients considered a poor medical risk due to a serious, uncontrolled medical disorder, non-malignant systemic disease or active, uncontrolled infection. Examples include, but are not limited to, uncontrolled ventricular arrhythmia, recent (within 6 months) myocardial infarction, uncontrolled major seizure disorder, unstable spinal cord compression, superior vena cava syndrome, or any psychiatric disorder that prohibits obtaining informed consent. * Pregnant or breast feeding women. * Immunocompromised patients, eg, patients who are known to be serologically positive for human immunodeficiency virus (HIV). * Patients with known hepatic disease (eg, Hepatitis B or C). * Previous cancer treatment. * Patients currently enrolled in another clinical tria, except AGNOSTOS PROFILING. * Patients that are receiving chemotherapy, hormonal therapy (HRT is acceptable) or other novel agents. * Patients receiving live virus and bacterial vaccines.