Duchenne muscular dystrophy (DMD) is a genetic disorder of progressive muscle degeneration and weakness due to alterations in dystrophin, an essential protein to keep the muscles together. Due to its location on the X chromosome, DMD is predominantly found in male children, with females being asymptomatic carriers. Its frequency is one in 3,500 male births worldwide.
DMD Awareness Week took place from 13 to 19 February this year. Santhera Pharmaceuticals and ReveraGen BioPharma announced on 9 January that the US Food and Drug Administration (FDA) had accepted their new drug application (NDA) for vamorolone, a dissociative delta-9, 11 glucocorticoid analogue, a steroidal drug that targets NR3C1. The Prescription Drug User Fee Act (PDUFA) date is set for 26 October this year. Santhera and ReveraGen are using the positive results from the pivotal Phase IIb VISION-DMD study in support of the NDA. Vamorolone currently has orphan drug, fast track and rare paediatric disease designations.
On 23 January, RegenxBio announced it had begun recruiting patients for the Phase I/II AFFINITY DUCHENNE trial of RGX-202. RGX-202 uses RegenxBio’s proprietary NAV AAV8 vector to deliver a transgene for a microdystrophin protein. The Phase I/II trial is a multicentre, open-label dose evaluation and dose expansion that will enrol two cohorts of six paediatric patients, each aged from four to 11 years. In addition, RegenxBio is also recruiting patients for its observational screening study, AFFINITY BEYOND. This trial will help identify ideal patients for the AFFINITY DUCHENNE trial and other future trials for the treatment of DMD.
The EMA recently issued a supportive letter to the Critical Path Institute’s efforts to develop and validate its clinical trials simulation platform to aid in key design constructs to find new treatments for DMD. Also, the Collaborative Trajectory Analysis Project (cTAP) announced supportive evidence of a patient-centric alternative to the conventional use of genetically matched placebo control in clinical trials for the treatment of DMD. Results from a multicentre, multinational study of more than 700 patients, published in Neurology, showed less than a 2% change in motor function over the course of 48 weeks.