Considerations on long-term immuno-intervention in the treatment of multiple sclerosis: an expert opinion

Sequencing of disease-modifying therapies for relapsing-remitting multiple sclerosis: a theoretical approach to optimizing treatment

Multiple sclerosis (MS) is a chronic disease which usually begins in young adulthood and is a lifelong condition. Individuals with MS experience physical and cognitive disability resulting from inflammation and demyelination in the central nervous system. Over the past decade, several disease-modifying therapies (DMTs) have been approved for the management of relapsing-remitting MS (RRMS), which is the most prevalent phenotype. The chronic nature of the disease and the multiple treatment options make benefit-risk-based sequencing of therapy essential to ensure optimal care. The efficacy and short- and long-term risks of treatment differ for each DMT due to their different mechanism of action on the immune system. While transitioning between DMTs, in addition to immune system effects, factors such as age, disease duration and severity, disability status, monitoring requirements, preference for the route of administration, and family planning play an important role. Determining a treatment strategy is therefore challenging as it requires careful consideration of the differences in efficacy, safety and tolerability, while at the same time minimizing risks of immune modulation. In this review, we discuss a sequencing approach for treating RRMS, with importance given to the long-term risks and individual preference when devising a treatment plan. Evidence-based strategies to counter breakthrough disease are also addressed.

Circulating lymphocyte levels and relationship with infection status in patients with relapsing-remitting multiple sclerosis treated with daclizumab beta

BACKGROUND

Reversible lymphocyte count reductions have occurred following daclizumab beta treatment for relapsing-remitting multiple sclerosis.

OBJECTIVE

To analyse total and differential lymphocyte levels and relationship with infection status.

METHODS

In DECIDE, blood samples were collected at 12-week intervals from daclizumab beta- ( n = 919) or intramuscular interferon beta-1a-treated ( n = 922) patients. Infections/serious infections were assessed proximate to grade 2/3 lymphopenia or low CD4⁺/CD8⁺ T-cell counts. Total safety population (TSP) data were additionally analysed from the entire clinical development programme ( n = 2236).

RESULTS

Over 96 weeks in DECIDE, mean absolute lymphocyte count (ALC), CD4⁺ and CD8⁺ T-cell counts decreased <10% (7.1% vs 1.6%, 9.7% vs 2.0%, 9.3% vs 5.9%: daclizumab beta vs interferon beta-1a, respectively); shifts to ALC below lower limit of normal occurred in 13% versus 15%, respectively. Grade 3 lymphopenia was uncommon (TSP: <1%) and transient. Lymphocyte changes generally occurred within 24 weeks after treatment initiation and were reversible within 12 weeks of discontinuation. In DECIDE, mean CD4⁺/CD8⁺ T-cell counts were similar regardless of infection status. TSP data were consistent with DECIDE.

CONCLUSION

When observed, ALC and CD4⁺/CD8⁺ T-cell count decreases in daclizumab beta-treated patients were generally mild-to-modest, reversible upon treatment discontinuation and not associated with increased risk of infections, including opportunistic infections.