Effect of early highly effective treatment compared to an escalating treatment strategy in multiple sclerosis

In this project we evaluate the effectiveness of preferentially initiating highly effective treatment vs. an escalating treatment strategy at time of diagnosis in a real-world clinical setting. We compare treatment outcomes before and after the implementation of new guidelines in a Norwegian MS-clinic in 2017.

Patients diagnosed and starting a DMT between the 1st of October 2013 and the 31st of December 2017 (Escalating Treatment Strategy group (ETS)) or between the 1st of January 2018 and the 31st of December 2020 (High intensity Treatment Strategy (HiTS) group) were included in the study. Baseline was defined as date of treatment start. To compare the two strategy groups, we performed cox proportional hazard regression analyses to evaluate time to first new relapse, time to new MRI lesion(s), and time to medication switch.

71.6% of patients diagnosed under the escalation treatment strategy (ETS), while 27.5% received highly effective treatment. 77.5% of patients diagnosed under the HiTS strategy initiated highly effective treatment, while 17.8% still initiated low -medium effective treatment. Median follow-up duration was 8.0 years in the ETS group and 4.0 in the HiTS group. Patients in the HiTS-group experienced a 70 % lower risk of having a new relapse compared to those in the ETS-group, with a hazard ratio (HR) = 0.30 (95% CI: 0.17 -0.54). The risk of experiencing a new MRI lesion (T2 or GD1+) was reduced by 77 % in the HiTS-group, with an HR of 0.23 (95% CI: 0.12 - 0.44). Additionally, the risk of switching treatment was reduced by 67% for the patients receiving highly effective treatment at diagnosis, with an HR of 0.33 (95% CI: 0.25 -0.45).

The risk of clinical and MRI-revealed disease breakthrough, as well as the need to switch treatment was significantly lower in persons with MS who initiated highly effective treatment early, compared to those following an escalating treatment strategy.