BARCELONA—Patients with relapsing-remitting multiple sclerosis (MS) who receive daclizumab high-yield process (DAC HYP) for two years have significantly less brain volume loss than patients who receive intramuscular interferon beta-1a for two years, according to research presented at the 31st Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS). The effects of daclizumab, compared with those of interferon beta-1a, are not related to pseudoatrophy during the first 24 weeks of treatment, according to the investigators.
“These results are consistent with other MRI outcomes from DECIDE that showed significantly lower inflammatory and chronic brain MRI lesion activity for DAC HYP, compared with intramuscular interferon beta-1a,” said Douglas Arnold, MD, a neurologist at Montreal Neurological Institute and Hospital, and colleagues.
Compared with the general population, people with MS have more rapid brain volume loss that may lead to the accumulation of disability. Previous data suggest that intramuscular interferon beta-1a reduces brain volume loss at year 2.
To compare the effects of DAC HYP and intramuscular interferon beta-1a on brain volume change, Dr. Arnold and colleagues examined data from the DECIDE study, which compared these two drugs in people with relapsing-remitting MS. Participants in the randomized, double-blind trial received 150 mg of subcutaneous DAC HYP every four weeks or 30 mg of intramuscular interferon beta-1a once weekly for at least 96 weeks. Some participants continued in the study for as long as 144 weeks. Whole brain volume change was evaluated as the percentage brain volume change (PBVC) over the prespecified intervals of weeks 0 to 24, 24 to 96, and 0 to 96 using the structural image evaluation using normalization of atrophy (SIENA) method. The researchers performed subgroup analyses according to patients’ baseline demographics and clinical characteristics.
A total of 1,841 patients were enrolled in DECIDE. Patients’ mean age was 36, and 68% of participants were female. Mean duration of disease was approximately four years, the mean number of relapses in the previous year was approximately 1.5, and mean Expanded Disability Status Scale score was 2.5. Median brain volume was 1,498 cm3.
Annualized PBVC was significantly reduced in the DAC HYP group between baseline and Week 96, compared with the intramuscular interferon beta-1a group. The median annualized PBVC from baseline to Week 96 was -0.580 for interferon beta-1a and -0.553 for DAC HYP. Subgroup analyses indicated that annualized percentage brain volume loss between baseline and Week 96 was lower in the DAC HYP group than in the interferon beta-1a group across all subgroups, except in subgroups of patients who were male, had baseline T2 lesion volume equal to or above the median, and with MS diagnosis within three to 10 years.
Annualized percentage brain volume loss also was lower in the DAC HYP group, compared with the interferon beta-1a group in the period from baseline to Week 24 (-0.674 vs -0.745). Annualized PBVC also was reduced between weeks 24 and 96 for DAC HYP, compared with interferon beta-1a (-0.511 vs -0.549).