Study Evaluating TCH346 and Placebo Administered Once Daily in Patients With Amyotrophic Lateral Sclerosis (ALS)

Inclusion criteria: * clinical diagnosis of laboratory-supported probable, probable, or definite ALS; * sporadic or familial ALS; * ALS symptom onset for no more than 3 yrs at study entry; * FVC equal to or more than 70%; * patients who are either riluzole naive or patients who are receiving concomitant treatment with riluzole at a stable dose of riluzole (50 mg bid) at study start. Exclusion criteria: * Known or suspected chronic infectious disease including HIV, hepatitis B, or hepatitis C. * Clinically significant ECG abnormalities. * Known hypersensitivity to study drug or related drugs (e.g. selegiline, MAO-A and B inhibitors, or tricyclic antidepressants). * Patients treated with potent inhibitors of CYP1A2 or CYP3A4 (a list of such inhibitors will be provided to the investigator). * Treatment with MAO-A and B inhibitors (including selegiline) within the past 30 days.