An open-label, non-randomized, extension study to further investigate the long-term efficacy, safety, and tolerability of Guanabenz in patients with early childhood onset vanishing white matter (VWM)

Condition studied

Vanishing white matter

Investigational medicinal product(s)

Eligibility

Primary endpoint

Ambulation: change from baseline at VWM1 study start to the end of the VWM2 study in the ability to walk at least 10 steps without and with light support of one hand as assessed by clinical examination, by the Gross Motor Function Measure, version 88 (GMFM 88), item E, number 68-88 or Health Utility Index (HUI) item 9, score 1-4, depending on available data in historical controls.

Endpoint detail

Overall survival rate., Changes in quality of life (QoL) and disability of participants, measured from the start of VWM1 to the end of VWM2, assessed using: GMFM 88, GMFC-MLD, GMFCS, MACS, CFCS, ELFC-MLD, EDACS, HUI, LIPS, Vineland-3, EQ-5D-5L, and EQ-5D-Y (proxy and self-reporting from 8 years old)., Changes in brain MRI parameters from baseline at VWM1 study start to the end of the VMW2 study:  Diffusion Tensor Imaging (DTI)  Chemical Shift Imaging (CSI)  Neurite Orientation Dispersion and Density Imaging (NODDI)  Myelin Water Fraction Imaging (MWFI), Guanabenz PK parameters in plasma, such as Cmax, AUC, half-life (T1/2), and predicted trough concentration (Ctrough) at steady state, Guanbenz exposure analyzed versus the primary endpoint., Frequency, severity, and daily life impact of all AEs, including AEs of special interest, occurring from the start of VWM2 study treatment until the end of the VWM2 study.