An ancillary study of the ginivostat trial in Becker myopathy looking for more objective criteria

The primary endpoint for evaluating ginivostat in Becker muscular dystrophy is the change in fibrosis on muscle biopsy after one year of treatment. Based on the data collected at the initial visit of this trial, an Italian and Dutch team looked for correlations between the measurement of the fat fraction of the whole thigh and of the quadriceps on MRI, the percentage of fibrosis on the muscle biopsy of the biceps brachii and strength measurements (timed tests, MFM, right knee extension strength, elbow flexion strength).

  • The 51 participants in the study, aged 37.4 ± 10.99 years on average, show strong heterogeneity in muscle biopsy and fat fraction on MRI.
  • The fat fractions of the thigh and the quadriceps are high: more than 50% on average.
  • Total biceps brachii fibrosis and thigh and quadriceps fat fractions show a moderate, statistically significant correlation with all functional tests
  • Similarly, fibrosis is statistically correlated, also moderately, with the importance of the fatty fraction

These correlations suggest to the authors the possibility of using the fat fraction measured on MRI and histology as alternative evaluation criteria to functional tests, which are more subject to situational variations (fatigue, motivation, etc.)

 

Characterization of patients with Becker muscular dystrophy by histology, magnetic resonance imaging, function, and strength assessments. Comi GP, Niks EH, Cinnante CM, et al. Muscle Nerve. 2021 Dec 16.