A ‘promising and impressive’ study
The study is promising, according to Nicholas Johnson, MD, who comoderated the session where the study was presented. “They were able to show a slower rate of neurological degeneration or duration on both the lower and higher dose compared with the placebo. This is promising and impressive, in the sense that it’s a really large (trial) for a rare condition,” Dr. Johnson, vice chair of research at Virginia Commonwealth University, Richmond, said in an interview.
The study included 164 patients Europe, Australia, Israel, Tunisia, India, and the United States, who received 5-10 mg dexamethasone, 14-22 mg DSP, or placebo. Mean ages in each group ranged from 9.6 to 10.4 years.
In an intention-to-treat analysis, modified International Cooperative Ataxia Rating Scale (mICARS) scores trended toward improvement in the low-dose (–1.37; P = .0847) and high-dose groups (–1.40; P = .0765) when determined by central raters during the COVID-19 pandemic. There was also a trend toward improvement when determined by local raters in the low dose group (–1.73; P = .0720) and a statistically significant change in the high dose group (–2.11; P = .0277). The researchers noted some inconsistency between local and central raters, due to inconsistency of videography and language challenges for central raters.
An intention-to-treat analysis of a subgroup of 89 patients age 6-9, who were compared with natural history data from 245 patients, found a deterioration of mICARS of 3.7 per year, compared with 0.92 in the high-dose group, for a reduction of 75% (P = .020). In the high-dose group, 51.7% had a minimal or significant improvement compared with baseline according to the Clinical Global Impression of Change, as did 29.0% on low dose, and 27.6% in the placebo group.