Inclusion criteria

• Acute spinal cord injury paraplegic and tetraplegic patients with confirmed classification of ASIA A (C5 ≤ lesion ≤ T12; 4-14 days post-injury (i.e. study drug treatment must begin 4-14 days post injury) for paraplegic patients and for those tetraplegic patients who do not require artificial respiration at time of treatment initiation within the 4-14 days time interval. In those tetraplegic patients who still require artificial respiration in the 4-14 days time interval treatment can be initiated up to 60 days post-injury as soon as the patient is weaned off the respiratory machine.)
• Tetraplegic patients who were initially diagnosed as ASIA A (neurologically complete lesion) at screening and turned into ASIA B (neurologically incomplete lesion) at baseline.
• Hemodynamically stable (at baseline).
• For female patients of child bearing potential, written agreement to abstain from intercourse during the first 12 weeks of the study and then subsequent use of a double-barrier local contraception, i.e. intra-uterine device plus condom, or spermicidal gel plus condom for up to one year post study drug treatment. Patients must receive documented counseling on contraceptive measures.

Exclusion criteria

• Complete anatomical transection confirmed by MRI or trauma caused by ballistic or other injury that directly penetrates the spinal cord including gunshot and knife wounds.
• Magnetic Resonance Imaging (MRI) indicating complete obstruction of the intrathecal space.
• Presence of one of the following:
• multiple spinal cord lesions
• cauda equina damage
• major brachial or lumbar plexus damage/trauma
• significant head trauma (e.g. cortical damage/lesion), or other injury that was, in the opinion of the investigator, sufficient to interfere with the assessment of the spinal cord function or otherwise compromise the validity of the patient's data.
• Other significant preexisting or current systemic disease such as lung, liver (exception: history of uncomplicated Hepatitis A), gastrointestinal, cardiac, immunodeficiency (including human immunodeficiency virus [HIV]) or kidney disease; or active malignancy or any other condition as determined by history or laboratory investigation that could cause a neurological deficit including syphilis, myelopathy, clinically relevant polyneuropathy, etc.
• History of meningitis, meningoencephalitis, epilepsy or life-threatening allergic or immune-mediated reaction.
• History of or current autoimmune disease or an acute episode of Guillain-Barre syndrome.
• Patients with uncontrolled bleeding diathesis and/or on concomitant treatment with coumarin anticoagulant.
• Presence of any unstable medical or psychiatric condition (defined by the Diagnostic and Statistical Manual of Mental Disorders-IV [DSM-IV]) that could reasonably have been expected to subject the patient to unwarranted risk from participation in the study or result in a significant deterioration of the patient's clinical course.
• Pregnant or nursing (lactating) women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive human chorionic gonadotropin (hCG) laboratory test (> 5 mIU/ml).
• Hemoglobin levels below 8.0 g/dl and/or patients who required greater than 10 (ten) blood transfusions since the acute injury
• Patients with concomitant treatment with Metamizole from Screening until end of Follow Up phase

Other protocol-defined inclusion/exclusion criteria may apply