Jefferies analyst Gena Wang noted that, according to a recent modification to clinicaltrials.gov records, Sarepta has extended the treatment duration of the Phase 3 study for exon45/53 skipping to 2 years from 1 year, which she believes as likely being due to feedback from the FDA and/or a lack of confidence that clinical efficacy can be achieved at 48 weeks. The analyst, who thinks the trial modifications have an overall negative readthrough to eteplirsen, continues to see a slim chance for approval for eteplirsen and keeps an Underperform rating on Sarepta shares.