1. Diagnosis of probable or definite Amyotrophic lateral sclerosis, according to the revised version of the El Escorial World Federation of Neurology criteria
2. Time since onset of first symptom of Amyotrophic lateral sclerosis less than or equal to 24 months. Date of Amyotrophic lateral sclerosis symptom onset. For the purposes of this study, the date of symptom onset will be defined as the date the subject first had symptoms of their disease, i.e., limb weakness, dysarthria, dysphagia, shortness of breath, or fasciculations, from the screening visit.
3. Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised score of greater than or equal to 35 at screening.
4. Slow vital capacity: greater than or equal to 60% of predicted capacity at the screening visit.
5. Be able to swallow capsules.
6. Either not currently receiving riluzole/sodium phenylbutyrate and taurursodiol/tofersen or on a stable dose of riluzole/sodium phenylbutyrate and taurursodiol/tofersen for at least 4 weeks before the screening visit. Subjects receiving riluzole/sodium phenylbutyrate and taurursodiol/tofersen are expected to remain on the same dose throughout the duration of the study.
7. Either not currently receiving edaravone or on edaravone treatment. Subjects receiving edaravone must have completed at least 1 cycle of treatment before the screening visit and are expected to continue with a stable dose of edaravone treatment throughout the duration of the study.
8. Capable of providing informed consent and complying with study procedures in the opinion of the investigator

1, Presence of unstable psychiatric disease, cognitive impairment, dementia, or substance abuse that would impair the ability of the subject to provide informed consent, in the opinion of the investigator.

1. Serious illness (e.g., pneumonia, septicemia) within 4 weeks of the screening visit; infection requiring hospitalization or treatment with intravenous antibiotics, antivirals, or antifungals within 4 weeks of screening; chronic bacterial infection (such as tuberculosis) deemed unacceptable as per the judgment of the investigator.
2. Active herpes zoster infection within 2 months prior to the screening visit.
3. Any medical condition that promotes suicidal attempt or behavior within 6 months prior to the screening visit and in the opinion of the investigator might interfere with subject's participation in the study or is a risk for a suicide attempt.
4. History of unstable or severe cardiac, pulmonary, oncological, hepatic, or renal disease or active cancer or another medically significant illness other than Amyotrophic lateral sclerosis, precluding safe participation of subject in this study in the opinion of the investigator.
5. Known allergy, sensitivity, or intolerance to Investigational product or excipients.
6. Subjects who have taken concomitant medications that are substrates of drug metaboliz-ing enzymes (Cytochrome P450 1A2 and/or Cytochrome P450 2B6) within 7 days or 5 half-lives of the medication (whichever is longer) before the first dose of Investigational product and throughout the study.
7. Use of any steroids, colchicine, or anti-IL-1 inhibitors within 7 days or 5 half-lives of the medication (whichever is longer) prior to the first dose of Investigational product administration.
8. Use of any investigational drug concurrently or within 4 weeks or 5 half-lives (whichever is longer) prior to the first dose of Investigational product administration.
9. Any clinically significant condition and/or laboratory significant value that would prevent the subject from participating in the study in the opinion of the investigator.
10. Received a live vaccine within 14 days before the screening visit or planning to receive during the study duration.

Note: The complete list of exclusion criteria can be found in the protocol.