To compare the efficacy and safety of the two therapeutic strategies in this population. 

Two therapeutic strategies coexist in multiple sclerosis (MS): the therapeutic escalation and the strategy of Induction. The Afro-Caribbean population is subject to more severe forms of MS. No data is comparing the efficacy and safety of these strategies in this population.

Multicenter retrospective observational study involving 195 patients treated for MS, including 66 in an Induction strategy, with a follow-up of at least two years. The primary endpoint was the irreversible achievement of the Expanded Disability Status Scale (EDSS) 3, 6, and 8 under treatment. The secondary endpoints concerned the change in the EDSS score under treatment, the determination of possible risk factors for irreversible crossing of the EDSS, and the occurrence of severe adverse effects. 

The irreversible crossing of the EDSS 3 was reached slower for the Induction versus Escalation strategy (median survival 13.5 years versus 9.8 years, p = 0.024). In univariate analysis, the choice of the Escalation strategy (HR 2.42, 95% CI [1.09 – 5.34], p = 0.029), the age at the time of the first relapse (P1) (HR 1.04, 95% CI [ 1.01 – 1.06], p = 0.004), and an incomplete regression of symptoms at P1 (HR 1.69, 95% CI [1.02 – 2.77], p = 0.040) were significantly associated with irreversible crossing of the EDSS 3. The EDSS worsened in the Escalation group (+2 (IQR 0 – 3)) while it remained stable or even decreased in the Induction group (0 (IQR -2 – 0)) (p < 0.001). Regarding the safety profile, there was no difference between the two strategies.

In the Afro-Caribbean population, the Induction strategy appears more effective than Escalation in extending the median time to irreversible EDSS 3 crossing. The Induction strategy should be used as first-line treatment in this population.