.... so with 500 potential participants why is this trial taking...

.... so with 500 potential participants why is this trial taking so long? Does anyone here know?

My guess…

1. As explained by Vapor, the 3-stage nature of the trial, based on age, considerably lengthens trial duration.
2. Trial eligibility is restricted to those aged 3-17 years weighing > 12 kg. Those with Angelman syndrome have a near-normal life expectancy so the eligible age group for this trial represents perhaps just 20% of the 500 diagnosed Angelman syndrome patients in Australia.
3. There is another Angelman syndrome clinical trial currently recruiting in Australia. Ultragenyx is assessing its investigational antisense therapy in a Phase 1/2 trial and is targeting recruitment of 80 patients across 4 nations, including the US and Australia. Trial eligibility is restricted to those aged 4-17 years. One of the trial sites is the Queensland Childrens’ Hospital in Brisbane, which is also one of the three recruitment sites for Neuren. As some kind of comparison, Ultragenyx is allowing almost 6 years for completion of its Phase 1/2 trial.
4. Neuren clinical trial sites are restricted to Brisbane, Sydney and Melbourne. Fifty percent of the Australian population lives elsewhere and travel challenges associated with the trial might deter some potential participants.