RIPK1 and amyotrophic lateral sclerosis: A selective and brain-permeable RIPK1 inhibitor DNL747 was designed subsequently and announced in 2020 for a phase Ib/II clinical trial in ALS [105], but the study was paused when it was concluded that higher doses—which were likely to cause adverse effects according to studies with cynomolgus monkeys [106]—would be needed to improve efficacy.