Sunday, November 27, 2016

Challenges ahead for trials in Friedreich’s ataxia

David R Lynch, Elizabeth Kichula, The Lancet Neurology, Volume 15, Issue 13, December 2016, Pages 1300-1301, ISSN 1474-4422, doi:10.1016/S1474-4422(16)30281-2.

Nevertheless, although natural history studies such as EFACTS identify the problems in progressing with therapeutic trials in Friedreich’s ataxia, they also identify one mechanism for keeping trials small: stratification.
In all of the natural history studies of Friedreich’s ataxia including the EFACTS, individuals with longer GAA repeat lengths had faster progression.

Progression characteristics of the European Friedreich’s Ataxia Consortium for Translational Studies (EFACTS): a 2 year cohort study

Kathrin Reetz, Imis Dogan, Ralf-Dieter Hilgers, Paola Giunti, Caterina Mariotti, Alexandra Durr, Sylvia Boesch, Thomas Klopstock, Francisco Javier Rodriguez de Rivera, Ludger Schöls, Thomas Klockgether, Katrin Bürk, Myriam Rai, Massimo Pandolfo, Jörg B Schulz, The Lancet Neurology, Volume 15, Issue 13, December 2016, Pages 1346-1354, ISSN 1474-4422, http://dx.doi.org/10.1016/S1474-4422(16)30287-3.

"To detect a 50% reduction in SARA progression at 80% power, 548 patients would be needed in a 1 year clinical trial and 184 would be needed for a 2 year trial."

In conclusion, our results of the 2 year analysis of the EFACTS cohort allowed substantiation of the suitability of the SARA and ADL as robust outcome measures for future therapeutic trials, which should be designed with an observational period of at least 2 years.