Current Status of Drisapersen Studies: analyses and assessment of next steps are ongoing

Dear Patient Group Representative,

On the 20^th of September this year, we shared the results about our Phase III study (DMD114044) of drisapersen in boys with Duchenne Muscular Dystrophy – we did not see a statistically significant difference in 6 Minute Walk Distance, the primary endpoint,  between the boys who received drisapersen and those who received placebo. At that time, the dosing of drisapersen within the ongoing clinical studies was placed on hold and we set about evaluating the results in the context of the overall clinical programme together with performing additional analyses to fully understand the results of the Phase III study.

It was anticipated that these additional analyses were to be completed by year end, but together with Prosensa, we are still analysing the results and assessing our next steps.  The outcome of the evaluation, which will include integrated results across the overall drisapersen clinical programme, including data from the long term extension studies, is anticipated in January 2014. In addition, as publicly announced at the recent PPMD Duchenne Policy Forum, the FDA is currently looking at the drisapersen data, in part to understand clinical and biomarker endpoints.

We are taking additional time to ensure that we have addressed the key questions to support our assessment on the overall benefit-to-risk profile of drisapersen in boys with DMD.  Until then, dosing of drisapersen will continue to be held within the ongoing studies. Study investigators will also be informed. In the meantime, per GSK’s policy, we will be posting a summary of the DMD114044 results on GSK Clinical Study Register (www.gsk-clinicalstudyregister.com).

We appreciate that this is a difficult time for the boys and their families and thank them for their patience as we thoroughly explore the data from the drisapersen clinical development programme. We want to ensure that we are making informed decisions regarding this program for the best interest of the boys with DMD. We currently plan to communicate the final assessment of our next steps during the early part of 2014.

Please note that our offices will be closed from 24 Dec 2013 to 1 Jan 2014 and we will respond to any questions that you may have regarding this communication as soon as we can.  We would like to take this opportunity to thank you once again for the efforts and support you provide to help the boys with DMD.

With best wishes for the holidays.

Kind regards

GSK Global Patient Relations Team