It was an open label study to evaluate safety, tolerability and brain microglia response in participants with Amyotrophic Lateral Sclerosis (ALS) following multiple doses of BLZ945.
                                
                                
                             
                            
                                
                                
                                    The purpose of the study was to identify a dose (or doses) of BLZ945, that measurably decrease(s) 18 KDa Translocator Protein (TSPO) binding in the brain of participants with ALS. The study also aimed to evaluate the safety and tolerability of BLZ945 in participants with ALS at different doses and dosing regimens, and safety related effects on extracellular matrix (ECM) accumulation.  This was an exploratory, adaptive , open label study of approximately 16 participants in cohorts of 4 participants per cohort at increasing doses of BLZ945 with the last dose determined after the completion of cohorts 1 to 3.  Each cohort received treatment for 4 days and continued with a 32 day follow up period with an end of study visit at day 36.  After completion of the 4 initial cohorts a fifth cohort was initiated with two parallel arms receiving BLZ945 for up to 12 weeks at two different treatment regimens, either once weekly or 4 days of treatment followed by 10 days off drug.
                                
                                
                             
                            
                                
                                
                                    Inclusion Criteria:
  -  Able to communicate well with the investigator, to understand and comply with the
     study visits and procedures of the study
  -  Written informed consent must be obtained before any assessment is performed.
  -  Male and female participants who are 18 years old or older at screening, and who are
     diagnosed with familial or sporadic ALS according to the World Federation of
     Neurology Revised El Escorial criteria of either bulbar or limb onset.
  -  Disease duration from symptoms onset no longer than 48 months at the screening
     visit.
  -  Females of childbearing potential must have a negative pregnancy test at screening
     and/or baseline.
  -  Treatment with approved ALS therapies is allowed, but participants need to be on a
     stable dose and regimen for at least 30 days prior to baseline.
  -  Having completed the Core Treatment Period to be able to continue in the Extended
     Treatment Period.
Exclusion Criteria:
  -  A history of clinically significant ECG abnormalities
  -  Active medical or neurologic diseases other than ALS, that in the opinion of the
     investigator would limit their participation in the current study.
  -  Use of other investigational drugs within 5 half-lives of screening, or until the
     expected PD effect has returned to baseline, whichever is longer; or longer if
     required by local regulations.
  -  History of hypersensitivity to any of the study treatments or excipients or to drugs
     of similar chemical classes.
  -  Presence of human immunodeficiency virus (HIV) infection based on screening lab
     results.
  -  Evidence of active or latent tuberculosis as assessed by Quantiferon testing at the
     screening visit.
  -  Positive serology for hepatitis B surface antigen, or hepatitis C antibodies
     confirmed by an appropriate licensed test at screening.
  -  Signs or symptoms, in the judgement of the investigator, of a clinically significant
     systemic viral, bacterial or fungal infection within 30 days prior to the screening
     visit.
  -  Cardiac disorders, such as recent cardiac history (within 6 months of screening) of
     acute coronary syndrome, acute heart failure, or significant ventricular arrhythmia
     at the screening visit or participants with a history of severe pulmonary
     hypertension. Participants with cardiac failure class 3 or 4 of the NYHA
     classification, or history of reduced LVEF or individuals with implanted cardiac
     pacemaker, or defibrillator.
  -  Significant hematological laboratory abnormalities.
  -  Clinical evidence of liver disease or liver injury or any of the following hepatic
     conditions at the screening visit:
  -  Women of child-bearing potential, defined as all women physiologically capable of
     becoming pregnant, unless they are using highly effective methods of contraception
     during dosing and for 14 days after last dose of BLZ945.
  -  Pregnant or nursing female participants
  -  Sexually active males unless they use a condom during intercourse while taking the
     drug during treatment, for 14 days after stopping BLZ945 and should not father a
     child in this period.
  -  History or presence of impaired renal function at the screening visit.
  -  Active suicidal ideation.
  -  History of drug abuse or harmful alcohol use within the 12 months prior to dosing
     within the judgement of the investigator, or evidence of such abuse as indicated by
     the laboratory assays conducted during screening.
  -  Active GI conditions such as Barrett's esophagus, achalasia, esophageal varices and
     active or history of esophageal cancer, pre-existing pancreatic disease at screening
     visit.
  -  History of active vasculitis or history of autoimmune disease autoimmune disease
     associated with vasculitis (eg., RA, SLE, Sjögrens disease, scleroderma).
  -  History or active cardiac valve disorder, congenital valve disease, or other
     clinical condition that might affect cardiac valve function
  -  Use of systemic anticoagulation that cannot be temporarily paused before study
     procedures
  -  Abnormal values on CT scan or echocardiography, signs of vasculitis, or evidence of
     a significant medical condition meeting treatment discontinuation criteria will be
     exclusionary for continuation in the extended treatment period.
  -  Participants who are planning to initiate treatment with an additional approved ALS
     therapy in the next 24 weeks are not allowed to continue in the extended treatment
     period.