Sustained efficacy and
safety of idebenone in the treatment of
update on a 2-year double-blind multicentre study.
Gutzmann H, Hadler D.
J Neural Transm Suppl 1998;54:301-10
The 2-year efficacy and safety of idebenone were studied in a prospective,
randomized, double-blind multicentre study in 3 parallel groups of patients
with dementia of the Alzheimer type (DAT) of mild to moderate degree. A total
of 450 patients were randomized to either placebo for 12 months, followed by
idebenone 90 mg tid for another 12 months (n = 153) or idebenone 90 mg tid for
24 months (n = 148) or 120 mg tid for 24 months (n = 149). The primary outcome
measure was the total score of the Alzheimer's Disease Assessment Scale (ADAS-Total)
at month 6. Secondary outcome measures were the ADAS cognitive (ADAS-Cog) and
noncognitive score (ADAS-Noncog), the clinical global response
(CGI-Improvement), the SKT neuropsychological test battery, and the Nurses'
Observation Scale for Geriatric Patients (NOSGER-Total and IADL subscale).
Safety parameters were adverse events, vital signs, ECG and clinical
laboratory parameters. During the placebo controlled period (the first year of
treatment), idebenone showed statistically significant dose-dependent
improvement in the primary efficacy variable ADAS-Total and in all the
secondary efficacy variables. There was no evidence for a loss of efficacy
during the second year of treatment, as a further improvement of most efficacy
variables was found in the second year in comparison to the results at the 12
months visit. Also, a clear dose effect relationship (placebo/90 mg <
idebenone 90 mg < idebenone 120 mg) was maintained throughout the second
year of treatment. This suggests that idebenone exerts its beneficial
therapeutic effects on the course of the disease by slowing down its
progression. Safety and tolerability of idebenone were good and similar to
placebo during the first year of treatment and did not change during the