A follow-on Study to Assess Long-term Safety and Tolerability of i.c.v Administration of sNN0029 in Patients With ALS

Inclusion Criteria: 1. Previous participation in sNN0029-003 with completion of 12 weeks study without clinically significant safety concerns 2. Intact continuity of the Medtronic SynchroMed® II Infusion System as judged by X-ray of head and abdominal area 3. Clinical diagnosis of ALS classified as definite, or probable with or without additional laboratory evidence, according to the revised WFN El Escorial criteria 4. Patient has been given written and verbal information about the continuation study, has had the opportunity to ask questions about the study, and understands the time and procedural commitments 5. Patient has given oral and / or signed consent (written) to participate in the study. In the event that a patient who gives oral informed consent is not physically able to sign the informed consent form (ICF) due to disease progression, a witness may sign the informed consent form on the patient's behalf Exclusion Criteria: 1. Hypertension defined as blood pressure \>160 mmHg systolic or \>90 mmHg diastolic 2. Ophthalmological examination (fundus photography, visual acuity and perimetry) with any clinically significant findings that imply safety concerns for this study. 3. Diagnosis of diabetes mellitus 4. Presence of risk for increased or uncontrolled bleeding and/or risk of bleeding that cannot be not managed optimally due to: * Anatomical factors at or near the implant site (e.g., vascular abnormalities, neoplasms, or other abnormalities) * Underlying disorders of the coagulation cascade, platelet function, or platelet count (e.g., haemophilia, Von Willebrand's disease, liver disease, or other medical conditions) 5. Presence of additional risk factors for thromboembolism such as obesity (Body mass index \[BMI\] \> 35) or use of oestrogens including combined contraceptive pills 6. Clinically significant abnormalities in haematology or clinical chemistry parameters as assessed by the investigator 7. Ongoing medical condition that according to the investigator would interfere with the conduct and assessments in the study. Examples are medical disability (e.g., severe degenerative arthritis, compromised nutritional state, peripheral neuropathy) that would interfere with the assessment of safety and efficacy of investigational product or device performance, or would compromise the ability of the patient to undergo study procedures (e.g., MRI), or to give informed consent 8. For women only: pregnant, breast feeding and/or for fecund women unwillingness to use adequate contraception during the trial such as: * Established use of oral, injected or implanted hormonal methods of contraception that do NOT contain oestrogens * Placement of an intrauterine device * Barrier methods of contraception: Condom or occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository