Utilisation of disease modifying treatment and diversity of treatment pathways in relapsing remitting multiple sclerosis

Background: There is minimal information on the utilisation of Disease Modifying Treatment (DMTs) for multiple sclerosis. The appropriate and safe use of medicines is informed by utilisation studies. Outcomes can inform health interventions to improve appropriate use of medicines and post marketing surveillance activities to improve safety. Objective: To evaluate utilisation and treatment patterns of disease modifying treatments (DMTs) for relapsing remitting multiple sclerosis (RRMS). Methods: A representative sample of the Australian pharmaceutical benefits scheme data were analysed (2006–2016). Demographics of incident users and trends in incident and prevalent users were determined. Individual patient treatment pathways were determined by sequential initiation of medicines in two different periods (2006–2013 and 2014–2019). Results: There were 20,660 patients with at least one dispensing of a DMT for RRMS during the study period (median age 41 years, 75% female). Incident and prevalent use increased by 20% and 88%, respectively. The market was responsive to 13 new listings of DMTs over the study period. Sequential treatment was found for 66% of initiators in 2006–2013 and 28.5% of initiators in 2014–2019. Diverse treatment pathways were found, with 278 and 93 unique sequences in 2006–2013 and 2014–2019, respectively. Conclusion: The availability of new DMTs has influenced both initial treatment choice and prevalence of users. Individualised treatment patterns and exposure to multiple medicines over time will challenge traditional pharmacovigilance systems.