Second-Line Therapy in Multiple Sclerosis

Abstract

Multiple sclerosis (MS) patients with breakthrough disease on immunomodulatory drugs are frequently offered to switch to second-line treatment (SLT). No head-to-head study has been performed yet to assess whether SLT is more effective than classical immunomodulators. We aim to retrospectively assess the moment of introduction, efficacity and tolerance of SLT. We retrospectively enrolled the patients in our department with relapsing-remitting MS (RRMS) who received first-line treatment (FLT) for more than 12 months than switched to SLT for 5 consecutive years. Outcome measures were Rio Score (RS) and modified Rio Score (MRS), annualized relapse rate (ARR) and changes in expanded disability status scale (EDSS) score. We also reported the side effects developed under SLT. We enrolled 20 patients, 6 males and 13 females. They all received interferon before switch. Twelve were switched to Natalizumab (NAT) and eight to Fingolimod (FIN). When switch was decided, 16 patients (80%) had high RS (2 or 3) and 19 (95%) had high MRS (2 or 3). Mean ARR was at 2.4 at the switch to SLT, it decreased significantly to 0.73 (70%) after 12 months and 0.4 (84%) after 5 years (p< 0.001). Nine patients were relapse-free after 12 months (75%) and 5 after 5 years (25%). Mean EDSS was at 3.36 at the switch to SLT, it significally decreased to 3 after 12 months and 1.5 after 5 years (p< 0.001). Side effects reported in 6 cases (30%); 3 cases of lymphopenia under FIN, 2 cases of lymphocytosis and on case of BK virus urinary infection under TYS. MRS was better to predict suboptimal interferon responders than RS in our study. SLT was more effective than interferon on disease progress and activity during the first 5 years of treatment. However, prospective head to head studies are needed to get higher evidence level.