Whose start before treatment the present invention relates to a kind of for treating variation amendment amyotrophic lateral sclerosis Evaluation of Functional scale (alsfrs r) with not aggressive or medium pushing amyotrophic lateral sclerosis (ALS) change rate, monthly < 1.1 point, the method include give tyrosine kinase inhibitor or mast cell inhibitor, especially masitinib or its pharmaceutically acceptable salt or solvate, optionally at least one active pharmaceutical ingredient.