Inclusion Criteria:

- adult patients, >/= 18 years of age

- advanced solid tumour

- dose-escalation phase: either relapsed/refractory disease after prior therapy or
melanoma patients with newly diagnosed (treatment-naïve) unresectable AJCC stage IIIC
or stage IV disease are eligible

- melanoma extension phase: newly diagnosed unresectable AJCC stage IIIC or IV disease

- colorectal cancer extension phase: relapsed/refractory metastatic disease

- confirmed BRAF V600 mutation status; for extension phases confirmation by Cobas test
required

- ECOG performance status 0-1

- adequate liver, renal and bone marrow function

Exclusion Criteria:

- patients for whom standard therapy exists and is considered appropriate by the
investigator

- for melanoma patients in the extension phase: prior systemic therapy for advanced
disease (prior adjuvant immunotherapy allowed)

- prior treatment with an inhibitor of BRAF (sorafenib allowed)

- active CNS lesions, or history of or known carcinomatous meningitis

- treatment with any chemotherapy, radiotherapy, immunotherapy or investigational agent
within 28 days prior to first dose of study drug

- anticipated or ongoing anti-cancer therapies other than those administered in this
study

- serious cardiovascular illness within the 6 months prior to study drug administration