A 2D animation shows how the change in the SMN2 gene produces a different protein through RNA splicing

Antisense Therapy for SMA

Antisense oligonucleotides (ASOs) are small molecules that can bind to RNA to change how it is spliced. A potential therapy for Spinal Muscular Atrophy (SMA) is to custom-design ASOs that will change the splicing of SMN2 to make more functional SMN protein.

Making Sense of Antisense and SMA

In patients with SMA, the SMN2 gene only produces a small amount of full-length, functional SMN protein, due to a change in RNA splicing of the SMN2 gene that results in a shortened version of the protein that is not functional. ASOs can “fix” splicing so that the full-length, functional SMN protein is produced.

  • Drs. Sharp and Sumner describe how RNA splicing can be used as a therapy for SMA
  • An animation shows how antisense oligonucleotide therapy for SMA utilizes RNA splicing
  • Dr. Krainer explains the science behind antisense therapy for SMA

Drug Delivery to the Spinal Cord

With SMA, the target area for medication is motor neurons in the spinal cord. Delivering drugs to the spinal cord is difficult, due to the “blood-brain barrier.” One potential method of drug delivery for SMA therapies is via intrathecal injection directly to the cerebrospinal fluid that surrounds the spinal cord.

  • Dr. Sumner explains how drugs can be delivered into the central nervous system
  • An animation shows how drugs for SMA may be delivered via infusion into the spinal cord
  • Dr. Sumner discusses the clinical trial process for SMA antisense oligonucleotide therapy