A Study of LY4256984 in Participants With Sporadic Amyotrophic Lateral Sclerosis

Inclusion Criteria:

• Have a definite, possible, or probable diagnosis of sporadic amyotrophic lateralsclerosis (ALS) made by a physician experienced with the management of ALS

• ALS symptom onset as determined by the Investigator within 24 months of Screening

• Have a body mass index (BMI) within the range of greater than or equal to 18.0 andless than or equal to 35.0 kilogram per square meter (kg/m²) (inclusive)

Exclusion Criteria:

• Have a history or presence of medical illness including, but not limited to, anycardiovascular, renal, hepatic, gastrointestinal, respiratory, hematological,endocrine, psychiatric, or neurological disease, convulsions, or any clinicallysignificant laboratory abnormality

• Have a history of another neurodegenerative disease or significant dementia/severecognitive problems

• Have serum alanine aminotransferase (ALT), aspartate transferase (AST), or totalbilirubin levels greater than 2 x upper limit of normal.

• Have a significant renal impairment (estimated glomerular filtration rate <60milliliters per minute [mL/min]/1.73 m²).

• Have a 12-lead electrocardiogram (ECG) abnormality at screening, in the opinion ofthe investigator, that increases the risks associated with participating in thestudy

• Show clinically significant abnormalities in lumbar spine previously known ordetermined by screening lumbar X-ray or fluoroscopy (if performed)