Inclusion criteria

1. Patients ≥18 years of age
2. Patients who are receiving octreotide or lanreotide monotherapy for acromegaly for at least 6 months, at a stable dose for the last 12 weeks.
3. IGF-1 at screening ≤1x ULN
4. Acromegaly diagnosis, defined as per protocol
5. Adequate bone marrow, hepatic and renal function
6. To enter Period 2 (Arms A and B): IGF-1 ≤1x ULN at Week 34, or up to Week 48 when treated with rescue medication
7. Other protocol-defined criteria apply

Exclusion criteria

1. Compression of optic chiasm causing visual defects
2. Symptomatic cholelithiasis or bile duct dilatation
3. Planned cholecystectomy during the trial duration
4. Acute or chronic pancreatitis
5. Pituitary radiotherapy
6. Uncontrolled hypothyroidism
7. Uncontrolled diabetes
8. Pituitary surgery within 6 months before screening or planned on trial
9. Treatment with pasireotide within 6 months prior to screening, pegvisomant or dopamine agonists within 3 months prior to screening
10. Recent or ongoing cardiovascular or thromboembolic diseases including heart failure, myocardial infarction, stroke, certain arrythmias, pulmonary embolism
11. Other protocol-defined criteria apply