In an article published in December 2022, an American team published the first results of a phase I/II clinical trial to evaluate the tolerance and efficacy of AAVrh74-MCK-GALGT2, a gene therapy product injected intravascularly into each thigh, in two boys with Duchenne muscular dystrophy (DMD), aged seven and nine years.
- The youngest participant, aged 7, received a higher dose of treatment.
- The treatment was well tolerated and no adverse effects were reported.
- A muscle biopsy performed three to four months after treatment showed increased expression of the GALGT2 gene compared to the pre-treatment baseline.
- The youngest participant who received the highest dose showed an improvement in his NSAA score (from 20 to 30 points) and an increase in the distance covered in the 6MWT test (from 405 to 478m) with a stabilisation of the timed floor survey.
- In contrast, in the low-dose boy, motor function deteriorated throughout the trial until loss of walking by 24 months post-treatment.
Although the small number of participants does not allow conclusions to be drawn about the therapeutic efficacy of the treatment, the positive results on the evolution of the young participant’s disease, which are more favourable than the natural history of the disease at this age, suggest that future trials should be conducted on younger people and with higher doses.
