Inclusion Criteria:  Possible, probable (clinically or laboratory supported) or definite ALS according to the revised version of the El Escorial criteria Disease duration < 18 months Vital capacity of more than 60% of normal (defined as slow vital capacity, best of three measurements) Age more than 18 years On a stable dose of riluzole for at least four weeks or not taking riluzole On a stable dose of edaravone for at least four weeks or not taking edaravone Capable of thoroughly understanding all information given and giving full informed consent according to GCP  Exclusion Criteria:  Previous participation in another clinical study within the preceding 12 weeks Proven SOD1- or FUS - mutation Tracheostomy or assisted ventilation of any type during the preceding three months Pregnancy or breast-feeding females Any medical condition known to have an association with motor neuron dysfunction which might confound or obscure the diagnosis of ALS Presence of any concomitant life-threatening disease or impairment likely to interfere with functional assessment Evidence of a major psychiatric disorder or clinically evident dementia precluding evaluation of symptoms Alcoholism Cardiovascular disorder/arrhythmia Impaired kidney function, defined as creatinine levels of 2.5 x upper limit of normal (ULN) Impaired liver function, defined as aspartate aminotransferase (AST) or alanine aminotransferase (ALT) of 3 x ULN Liable to be not cooperative or comply with trial requirements as assessed by the investigator, or unable to be reached in the case of emergency