This study will assess the pharmacodynamics, pharmacokinetics, safety and tolerability of BYM338 in patients with COPD and cachexia. The primary outcome will be a change in thigh muscle volume compared to placebo. The study will last for approximately 24 weeks.

Inclusion criteria:

• Written informed consent must be obtained before any assessment is performed.
• Males and females ages 40 to 80 years
• Smoking history of at least 10 pack-years
• Diagnosis of COPD according to GOLD guidelines (GOLD, 2010), with a post-bronchodilator FEV¬1 < 80% predicted and FEV1/FVC ratio < 0.70
• BMI <20 kg/m2 or skeletal muscle mass index by DXA < 7.25 kg/m2 for men or <5.45 kg/m2 for women.
• In general stable health, including managed COPD, by past medical history, physical examination, vital signs at baseline as determined by the investigator.

Exclusion criteria:

• Patients with MRC dyspnoea grade 5 (i.e. patients too breathless to leave the house or breathless when dressing)
• Plans for lung transplantation or lung reduction surgery within four months of enrollment
• Patients participating in a formal pulmonary rehabilitation program within 3 months of dosing
• History of malignancy of any organ system (other than excised non-melanomatous carcinoma of the skin), treated or untreated, within the past 5 years, regardless of whether there is evidence of local recurrence or metastases.
• Diseases other than cancer known to cause cachexia or muscle atrophy, including but not limited to congestive heart failure of any stage, chronic kidney disease (estimated GFR < 30 mL/min using the MDRD equation), rheumatoid arthritis, primary myopathy, stroke, HIV infection, tuberculosis or other chronic infection, uncontrolled diabetes mellitus, etc.
• Inflammatory bowel disease, celiac disease, short bowel syndrome, pancreatic insufficiency
• Use of any prescription drugs known to affect muscle mass, including androgen supplements, anti-androgens (such as LHRH agonists), anti-estrogens (tamoxifen, etc.) recombinant human growth hormone (rhGH), insulin, oral beta agonists, megestrol acetate, dronabinol, metformin, etc.
• Hemoglobin concentration below 11.0 g/dL at screening.
• Liver disease or liver injury.
• Use of other investigational drugs at the time of enrollment, or within 30 days and for any other limitation of participation in an investigational trial based on local regulations.
• Women of child-bearing potential.

Other protocol-defined inclusion/exclusion criteria may apply