Ataluren may preserve arm, hand function in nonsense mutation Duchenne muscular dystrophy

Key takeaways:

• Ataluren preserved hand-to-mouth function in boys with nonsense mutation Duchenne muscular dystrophy.
• Ataluren also tended to preserve overhead reach.

Ataluren preserved upper limb function in boys with nonsense mutation Duchenne muscular dystrophy, according to a poster presented at the MDA Clinical & Scientific Conference.

“Duchenne muscular dystrophy (DMD) is a severe neuromuscular disorder caused by a lack of functional dystrophin,” Christian Werner, Dr. Med., executive director of global medical affairs for DMD at PTC Therapeutics Inc. in Frankfurt, Germany, and colleagues wrote. “Ataluren promotes readthrough of an in-frame premature stop codon to produce full-length dystrophin and is indicated for the treatment of patients with nonsense mutation (nm) DMD.”

Werner and colleagues reviewed data from two studies. The first — the phase 3 Study 041 — was a 72-week, randomized controlled trial among boys aged 5 years or older who were on a stable corticosteroid regimen and who could walk 150 m or more in 6 minutes. In total, 359 boys (mean age, 8.1 years) received at least one dose of either ataluren or placebo plus standard care.

The second trial is the ongoing Strategic Targeting of Registries and International Database of Excellence (STRIDE) Registry study. STRIDE participants (n = 261) receiving ataluren and standard care were matched by propensity score to participants in the Cooperative International Neuromuscular Research Group Duchenne Natural History Study (CINRG DNHS) who were receiving standard care only.

From baseline to week 72 in Study 041, there was no significant difference in least-squares mean performance of upper limb (PUL) scores between the ataluren and placebo groups. In a subgroup of participants who walked 300 m to 400 m in 6 minutes, the ataluren group had more improvement in PUL scores compared with the placebo group (P = .0165).

In the STRIDE Registry study, ataluren was associated with preserved hand-to-mouth function by 3.4 years (P = .0046). Although differences in overhead reach were not significant between the STRIDE cohort and the CINRG DNHS cohort, STRIDE participants tended to be older than matched participants when they lost this function (15.8 years vs. 12.6 years).