The MDEX Consortium was formed to develop and test treatments for Duchenne muscular dystrophy. In the last few years the MDEX Consortium has focussed on a strategy of using patches of genetic material (Antisense Oligonucleotides) to restore production of the essential muscle protein dystrophin. Originally the work of the MDEX Consortium was funded by the Department of Health (UK) in 2005. This project was focused on the search of the most effective molecular patch to promote the restoration of dystrophin production in Duchenne boys carrying specific genetic changes (deletions). This culminated in a phase lb/lla clinical trial in a group of boys who received the molecular patch intramuscularly. This work has been recently completed (http://clinicaltrials.gov/ct2/show/record/NCT00159250). The outcome data of this study has been published in the journal Lancet Neurology (Volume 8, Issue 10, Pages 918 - 928, October 2009). A summary of the outcome can be seen under latest news on this website. A press release relating to this publication and presentation of data, including preliminary data on the current systemic trial at the World Muscle Society (WMS) conference in Geneva, Switzerland in September can be found on http://www.avibio.com/pr/pr439.php.

The activities of the MDEX Consortium are divided into several sections, each led by a different research group (see profiles) but with all members of the Consortium sharing results and meeting regularly. The project also benefits from regular input from a Scientific Advisory Board of experts (see Scientific Advisory Board).

The MDEX Consortium received funding from the UK Medical Research Council (MRC) and AVI BioPharma to perform a clinical trial to assess the safety and efficacy of the same molecular patch utilised in the previous intramuscular study, but this time administered intravenously and repeatedly. AVI BioPharma, the sponsor of the study released data on this dose escalation study in a press release on 02.06.10 (www.avibio.com). Briefly, (1) AVI-4658 was well tolerated in the trial to date and adverse events tended to be mild, transient and unrelated to the study drug, (2) all biopsies (12/12) at the four highest dose of 6 cohorts showed skipping of exon 51 in the dystrophin mRNA, a sign of systemic biologic activity, (3) all 8 patients in the two highest dose cohort and one other had increased dystrophin positive fibre counts, (4) first ever reported substantial de novo increase in dystrophin positive fibres (>50% of normal).

"These results are very encouraging and the muscle biopsies of the treated patients under the microscope gives a different picture from that typically observed in DMD boys" stated Professor Francesco Muntoni, the lead investigator of the trial. Stephen B Shrewsbury MD., Senior Vive president and Chief Medical Officer for AVI BioPharma added "we plan to review the clinical data with key opinion leaders and work with regulatory authorities to finalise our plans for additional clinical development, including identifying a dosing regimen to provide consistent results across potential treatable patients".

Both study sites are in the UK North Star Clinical network, which links 17 UK centres involved  in the diagnosis and management of DMD (http://www.muscular-dystrophy.org/how_we_help_you/for_professionals/clinical_databases) and would welcome referral of patients for future trials. See the latest news, Q&A in this website and the Clinical Trials website http://clinicaltrials.gov/ct2/show/NCT00844597. Future extended studies are currently in preparation.

The MDEX Consortium along with others, including industry associated in studies on antisense oligonucleotides in DMD met with the representatives of the European Medicines Agency (EMEA) on the 25th September 2009 in London. The purpose of the workshop was to identify pathways that may fast tract this advanced therapy through the regulatory process. A press release by TREAT-NMD relating to this workshop is available on http://www.treat-nmd.eu/patients/news/news/658/

Information on clinical trials in the USA relating to AVI-4658 is now available from David Walsey, Head of Invester Relations and Corporate Communications, AVI BioPharma ( This e-mail address is being protected from spam bots, you need JavaScript enabled to view it ).