Disease-modifying therapies for multiple sclerosis

### What you need to know A 32 year old woman with multiple sclerosis presented to her general practitioner with a five day history of numbness and weakness in the right leg. She felt well in herself and did not describe any symptoms to suggest an intercurrent infection. She had been taking weekly intramuscular injections of interferon beta-1a for the previous 18 months and reported flu-like symptoms that could last for up to 24 hours after each dose. She asked if there was a need to change her treatment and what alternatives were available. Multiple sclerosis is a chronic, immune-mediated, demyelinating disorder of the central nervous system affecting over two million people worldwide.1 It is a major cause of physical disability in young adults and can have profound implications for cognition, emotional wellbeing, and employment. Patients commonly present with unilateral visual loss (due to optic neuritis), double vision, sensory symptoms, limb weakness, or imbalance.2 The diagnosis is based on clinical features and findings on magnetic resonance imaging (MRI), sometimes supported by lumbar puncture and other investigations.23 Nearly 80-85% of people with multiple sclerosis experience a relapsing course: episodes (attacks or relapses) of new or worsening neurological symptoms lasting at least 24 hours, followed by full or partial recovery, in the absence of fever or infection (fig 1).3 If left untreated, most people with relapsing multiple sclerosis develop disability over time. This can …