- Patients with relapsing-remitting multiple sclerosis (MS) starting newer disease-modifying therapies had elevated risks for infections requiring hospitalization that varied by drug.
Why this matters
- Better understanding of these risks will help inform treatment decisions.
- Compared with crude infection incidence rate per 1000 person-years in general population (5.2), rate higher in patients receiving:
- Interferon-β (Avonex, Betaseron, Extavia, Rebif) and glatiramer acetate (Copaxone) (8.9).
- Fingolimod (Gilenya) (14.3).
- Natalizumab (Tysabri) (11.4).
- Rituximab (Rituxan) (19.7).
- When interferon-β and glatiramer acetate were comparator, adjusted risk significantly higher only for rituximab (HR, 1.70; 95% CI, 1.11-2.61).
- Relative to use with interferon-β and glatiramer acetate:
- Use of antibiotics higher with natalizumab (HR, 1.15; 95% CI, 1.01-1.31), rituximab (HR, 1.23; 95% CI, 1.08-1.40).
- Use of herpes antiviral drugs higher with fingolimod (HR, 1.82; 95% CI, 1.34-2.46), natalizumab (HR, 1.71; 95% CI, 1.27-2.32).
- Swedish 7-year nationwide retrospective cohort study:
- 6421 patients with relapsing-remitting MS initiating study drug.
- 42,645 age-, sex-matched MS-free individuals from general population.
- Main outcome: serious infections (those resulting in hospitalization).
- Funding: Patient-Centered Outcomes Research Institute; Swedish Foundation for MS Research.
- Reliance on registry data.
- Minor infections missed.
- Lack of information on some confounders.