Objective: Immunomodulatory drugs (IDs) (interferon beta (IFNgamma) and glatiramer acetate (GA)) reduce relapse rate and disease progression in relapsing remitting multiple sclerosis (RRMS) but extensive data are not available on the effectiveness and tolerability of these drugs in childhood or adolescence. The aim of this study was to evaluate the impact of IFNbeta and GA in MS patients treated before 16 years of age.
Methods: A research group (Immunomodulatory Treatment of Early onset MS (ITEMS)) was promoted in Italy to collect a large series of patients affected by clinically definite and RRMS and treated with IDs before 16 years of age. Fifteen centres recognized subjects suitable for inclusion: 76 patients (52 females) were collected with a mean age at onset of 12.4 (SD 2.5) years, a mean disease duration of 18.6 (SD 14.7) and a relapse rate of 3.1 (SD 2.9).
Results: Results were evaluated in 65 (45 females) subjects with a pretreatment and a treatment duration >3 months: 38 were treated with IFNbeta-1a once weekly (Avonex), 18 with IFNbeta three times weekly (16 with Rebif, 2 with Betaferon) and nine with GA (Copaxone). The mean pretreatment period was respectively 20, 18 and 9.2 months. The treatment duration lasted respectively 23.3, 40.7 and 33.3 months. The mean annualized relapse rate decreased dramatically during the treatment: from 2.4 to 0.4 in the Avonex group, from 3.2 to 0.8 in the Rebif-Betaferon group and from 2.8 to 0.25 in the GA group. The mean final EDSS scores were respectively (in brackets the initial scores): 1.3 (1.4), 1.6 (1.8) and 0.6 (1.1). In the whole group, the final score was unchanged or reduced in all subjects except eight. Clinical side effects were recorded in 41/65 subjects (mainly in subjects treated with IFNbeta), abnormal laboratory findings were observed in 13/65 subjects: they were transient in most cases. IFNgamma was stopped in six cases: in four because of inefficacy and in two cases because of side effects.
Conclusions: Sixty-five clinically definite MS subjects were treated during childhood or adolescence with IDs. The treatment reduced the relapse rate and the progression of the disease in most cases. Side effects were common in subjects treated with IFNbeta but were well tolerated in most cases.