Nevertheless, all DMTs reduce children’s annualized relapse rate (ARR), according to results presented at the 2020 CNS-ICNA Conjoint Meeting, held virtually this year.
“Our study adds weight to the argument for an imminent shift in clinical practice toward the use of newer, more efficacious DMTs in the first instance,” said Omar Abdel-Mannan, MD, of Great Ormond Street Hospital in London. MRI activity continues among patients treated with DMTs, and the number of relapses is highest in the period following diagnosis. But because the effect of treatment on brain atrophy is greatest in the initial period of disease, “this time period may represent a critical therapeutic window for the use of highly effective therapies,” said Dr. Abdel-Mannan.
An examination of medical records
MS is much less prevalent among children than among adults. Compared with adults with MS, children with MS have a higher relapse rate and slower accumulation of disability. The individual response to DMTs is variable, said Dr. Abdel-Mannan. Furthermore, current standards of care for pediatric MS vary by center and are based on adult protocols.
Dr. Abdel-Mannan and colleagues conducted a retrospective study to evaluate the real-world effectiveness of the newer oral and infusion DMTs, compared with the older injectable DMTs, in children with relapsing-remitting MS. They examined data from seven tertiary pediatric neurology centers in the United Kingdom and identified patients under age 18 years with relapsing-remitting MS who were treated with DMTs between 2012 and 2018. The investigators reviewed clinical and paraclinical data retrospectively using electronic medical records. They compared patients’ ARR, new radiological activity, and Expanded Disability Status Scale score pretreatment and on treatment.
The researchers included 103 patients in their analysis. The population’s median age was 14 years. The ratio of girls to boys was approximately 3:1. Whites and other races/ethnicities accounted for approximately equal groups of patients. About one-third of patients presented with a clinically isolated syndrome (CIS) in the form of transverse myelitis or optic neuritis. Two-thirds presented with other CIS phenotypes. Almost all children had an abnormal MRI at onset.
Most patients initiated injectable DMTs
Of the 103 patients, 89 started treatment with an injectable (e.g., glatiramer or interferon) or an older DMT. Fourteen patients began treatment with a newer DMT (e.g., dimethyl fumarate, fingolimod, natalizumab, and alemtuzumab). Three of the 89 patients on an injectable DMT switched to another injectable DMT, and two of these patients later escalated to a newer DMT. Thirty-five of the 89 patients who initiated an injectable DMT were escalated immediately to a newer DMT. One of these patients later switched to another newer DMT. Two of the 14 patients who started on a newer DMT as their first drug switched to another newer DMT.
The investigators observed a reduction in ARR for all DMTs used during the study period. Nevertheless, a significant number of patients receiving injectable DMTs continued to relapse on treatment. Almost all patients receiving newer DMTs, however, had a reduction in relapses. When Dr. Abdel-Mannan and colleagues performed Kaplan–Meier survival analysis, they found that patients receiving newer DMTs had a longer time to first relapse and a longer time to switch treatment over 2 years, compared with patients receiving injectable DMTs. In addition, patients receiving newer DMTs had a longer time to develop new radiological activity, compared with patients receiving injectables. The analysis also indicated that the proportion of patients with new radiological activity was higher than the proportion who had clinical relapses and an Expanded Disability Status Scale score increase of more than 1 point over 2 years.
In all, 55 of the children receiving injectable DMTs and 18 of the patients receiving newer DMTs had side effects. The most commonly reported side effects were flulike symptoms and injection-site reactions. Five patients discontinued or switched their DMTs because of side effects. “Reassuringly, no pediatric-specific side effects were reported,” said Dr. Abdel-Mannan. The newer DMTs had similar short-term safety, tolerability, and side-effect profiles in these children as in adult patients.
The study was conducted on behalf of the UK Childhood Inflammatory Demyelination Network. Dr. Abdel-Mannan had no relevant disclosures.
SOURCE: Abdel-Mannan O et al. CNS-ICNA 2020, Abstract PL10.