Inclusion Criteria:

- Histologically confirmed diagnosis of GIST that is unresectable and/or metastatic and
therefore not amenable to surgery or combined modality with curative intent.

- Radiologically confirmed disease progression during imatinib therapy at a dose of at
least 400 mg daily and/or radiologically confirmed disease progression during
sunitinib therapy OR documented intolerance to imatinib and/or sunitinib. (Patients
with prior additional investigational treatment of GIST prior to study entry can be
included.)

- At least one measurable site of disease on CT/MRI as defined by RECIST criteria.

Exclusion Criteria:

- Prior treatment with nilotinib.

- Treatment with any cytotoxic and/or investigational cytotoxic drug ≤ 4 weeks (6 weeks
for nitrosurea or mitomycin C) prior to Visit 1.

- Prior or concomitant malignancies requiring active treatment other than GIST with the
exception of previous or concomitant basal cell skin cancer, previous cervical
carcinoma in situ.

- Impaired cardiac function at visit 1

- Patients with severe and/or uncontrolled concurrent medical disease that in the
opinion of the investigator could cause unacceptable safety risks or compromise
compliance with the protocol e.g. impairment of gastrointestinal (GI) function, or GI
disease that may significantly alter the absorption of the study drugs, uncontrolled
diabetes.

Other protocol-defined inclusion/exclusion criteria may apply