TTR and neurodegenerative disease: In reference to this topic, the FDA has recently approved the first RNAi drug Onpattro (patisiran), which reduces levels of Transthyretin or TTR for the treatment of the neurodegenerative disease hereditary transthyretin amyloidosis [34,35] and the RNA-targeting oligonucleotide drug Spinraza (nusinersen) which increases levels of full-length Survival of motor neuron 2 or SMN2 for the treatment of the neuromuscular disease spinal muscular atrophy [36].