AVI BioPharma of Bothell, Wash., announced June 9, 2011, that the launch of its phase 2 trial of eteplirsen (pronounced eh-TEHP-lur-son; formerly called AVI4658) in Duchenne muscular dystrophy (DMD) at Nationwide Children's Hospital in Columbus, Ohio, has been delayed, following a request by the institutional review board for a revision to the study design.
The trial had been slated to start in late spring 2011.
AVI says the requested change is not related to either safety or the expected activity of eteplirsen, and that the company expects to submit a revised plan to the institutional review board later in June 2011.
Eteplirsen is an experimental exon-skipping drug designed to coax cells to ignore (skip) the exon 51 section of the dystrophin gene and make a functional dystrophin protein, which is needed in DMD. Phase 1-2 trials of the compound conducted in the United Kingdom have been promising.
Editor's note 7/28/11: The eteplirsen (AVI-4658) trial is now open at Nationwide Children's Hospital in Columbus, Ohio. See Eteplirsen (AVI-4658) Boosts Dystrophin Production in DMD.
The biopharmaceutical company Prosensa, based in Leiden, the Netherlands, has provided an update on its development of exon-skipping compounds for DMD.
The company is conducting a clinical trial of PRO044 (now closed to recruitment) in Belgium, Italy, the Netherlands and Sweden. PRO044 is designed to coax cells to skip the exon 44 section of the dystrophin gene and produce a functional dystrophin protein, which is needed in DMD.
Prosensa is also developing molecules designed to coax skipping of exons 45, 53, 52 and 55. These are at the preclinical (laboratory) stage.
PRO051/GSK2402968, in development jointly by Prosensa and pharmaceutical company GlaxoSmithKline, is being tested in clinical trials and is designed to cause skipping of exon 51 of the dystrophin gene. In April 2011, it was reported that this drug resulted in dystrophin protein production and increased walking distance in a 48-week trial conducted in Belgium and Sweden.
A trial at Cedars-Sinai Medical Center in Los Angeles will test tadalafil and sildenafil in DMD. Investigators are recruiting participants who are 7-15 years old, able to walk and meet other study criteria.
Participants will be randomly assigned to receive either tadalafil or sildenafil, which have been shown to improve muscle blood flow in a mouse model of DMD.