A Study of RO5083945 in Combination With Cisplatin and Gemcitabine or Carboplatin and Paclitaxel in Patients With Advanced or Recurrent Non-Small Cell Lung Cancer of Squamous Histology Who Have Not Received Prior Chemotherapy for The Metastatic Disease

Inclusion Criteria:

* Adult patients, \>/= 18 years of age
* Locally advanced (stage IIIB, excluding patients who are candidates for chemo-radiotherapy or radical thoracic radiotherapy), metastatic (stage IV) or recurrent squamous non-small cell lung cancer (NSCLC)
* Histologically documented squamous NSCLC. Mixed tumors should be categorized according to the predominant cell type
* Histological tumor tissue sample from initial diagnosis or new tumor biopsy representative of the disease
* Patients who have received adjuvant chemotherapy are eligible if the last administration of the prior adjuvant regimen occurred at least 3 months prior to enrollment
* At least one measurable disease lesion as per RECIST 1.1 criteria
* Eastern Cooperative Oncology Group (ECOG) performance status 0-1
* Adequate hematological, liver and renal function
* Females of childbearing potential must commit to using a reliable and appropriate method of contraception until at least 3 months after the end of the last dose of study treatment

Exclusion Criteria:

* Prior chemotherapy (excluding neoadjuvant/adjuvant chemotherapy/chemo-radiotherapy) or treatment with another systemic anti-cancer agent (e.g. monoclonal antibody, tyrosine kinase inhibitor)
* Radiotherapy within the last 4 weeks prior to first dosing, except for limited field palliative radiotherapy for bone pain relief
* Treatment with any other investigational agent within 30 days prior to starting study treatment or participation in another clinical trial (e.g. CTC blood collection) within 7 days prior to starting study treatment
* Historical or clinical evidence of central nervous system (CNS) metastases (except for previously treated CNS metastases in patients that are asymptomatic, have had no evidence of active CNS metastases for \>/= 3 months prior to first dose and have had no requirement for steroids or enzyme-inducing anticonvulsants in the last 14 days)
* Recent history of poorly controlled hypertension (systolic \>180 mmHg or diastolic \>100 mmHg)
* Severe uncontrolled illness, including poorly controlled diabetes mellitus and active or uncontrolled infection
* Hypersensitivity to the active substance or to any excipients or to any of the study drugs including premedication (corticosteroids, anti-histamine, paracetamol)
* Pregnant or breastfeeding women