Intestinal Microbiome Transplant in ALS

Who May Qualify: - Diagnosis of ALS according to Gold Coast Criteria - Age: 18+ years at enrollment - Fast-progressing (ALSFRS-R change of at least 1.5 points per month between last 2 measurements at screening) - Modestly but not severely affected (ALSFRS-R score at or above 24 at screening) - Able to swallow capsules and expected to be able to for the duration of the trial (ALSFRS-R "swallowing" score of 3 or 4 at screening) - Expected to survive for the duration of the trial - Taking any combination of riluzole, edaravone, and/or tofersen at a stable dose for 30 days prior to screening, or not taking any of these and not expected to during the study. - Capable of giving written consent. - If sexually active, must agree to use contraceptive or abstinence for duration of treatment. - Females of child-bearing age must have negative pregnancy test at screening. Who Should NOT Join This Trial: - Concurrent illness or laboratory abnormalities that could confound the measurement of ALS progression or the microbiome or interfere with the ability to complete the study. - Taking probiotics, nutraceuticals, or herbal remedies within 2 weeks of screening - Taking antibiotics within 3 months of screening. - Taking any investigational study drug within 30 days of screening or five half-lives of the prior agent. - Previous exposure to MTT. - Pregnancy. - Known specific food allergy with anaphylaxis - Other co-morbid conditions that, in the opinion of the study investigator, place the participant at increased risk of complications, interfere with study participation or compliance, or confound study objectives. Always talk to your doctor about whether this trial is right for you.