Observational study of markers in people with different types of ALS, on and not on Edaravone

This study is being conducted to help the investigators better understand how the new FDA approved medication Edaravone (also known as Radicava) works in subsets of patients with ALS. The investigators are also trying to understand if there are specific ALS patients, with different presentations of ALS, who might benefit most from this medication. Also, the investigators are following specific biomarkers to determine the optimal treatment duration in patients with different forms of ALS

There is no study medication being offered in this trial. Edaravone is prescribed as part of regular care. In this trial we are collecting blood, urine, and spinal fluid samples in ALS patients who are taking Edaravone and ALS patients who are not taking Edaravone to measure certain markers that could indicate why the drug may be working in a specific type of ALS.