Research Identifies Shifts in Prescribing Patterns for Multiple Sclerosis Disease-Modifying Therapies
Although popular at the turn of the century, the use of platform injectable therapies has subsided significantly with the introduction of oral agents, with became the most frequently initiated therapies by 2020.
Mackenzie Henderson, PharmD
Data from a recently published cross-sectional study showed significant changes in the prescribing patterns of disease-modifying therapies (DMTs) for patients with multiple sclerosis (MS), with patients receiving treatment earlier in their disease course and a shift away from injectable therapies.1
Published in JAMA Neurology, the trial included 153,846 DMT initiation episodes among adults (median age, 46 years) and 583 among children (median age, 16 years) from 2001 to 2020. In adults, new initiations for platform injectable therapies declined from 99.3% of all initiations in 2001 to 25.5% of all initiations in 2020 (P <.001). Interferon-beta showed the greatest decline, from 72.3% in 2001 to 11.1% in 2020 (P <.001). In contrast, initiations of glatiramer increased from 27% in 2001, peaked at 39.3% in 2009, and declined thereafter to 14.4% of initiations in 2020 (P <.001).
"The declining use of platform injectable DMTs corresponded largely with the availability of oral alternatives rather than the introduction of infusion DMTs," lead investigator Mackenzie Henderson, PharmD, postdoctoral fellow, Rutgers School of Public Health, and colleagues, concluded. "The exact reasons for these observed patterns cannot be determined from this study, but likely reflect several factors, including the convenience of administration, insurance limitations, and advertising strategies."
They added, "As new DMTs continue to enter the market, future research should evaluate the impact that these approvals will have on MS treatment patterns."
In the past 2 decades alone, more than 10 new DMTs have been approved for MS treatment in the US, introducing new drug classes and routes of administration to the market. Oral DMTs became available in 2010 and have provided an alternative, more convenient form of administration compared with injectable and infusion therapies. Results from the study showed that the decline in platform injectables corresponded strongly with the introduction of oral therapies, rather than the availability of infusion DMTs in 2004.
Infusion therapies accounted for only 3.2% of initiations since 2004, with a modest increase in 2017 with the introduction of ocrelizumab (P <.001 for trend). While oral therapies accounted for only 1.1% of adult initiations in 2010, that number rose to 62.3% in 2020 (P = .003). Dimethyl fumarate, the most frequently initiated oral agent within its class, peaked at 36.4% of all initiations in 2013 and declined modestly thereafter to 23.3% of initiations (P =.001 for trend).
The increase in oral DMT use among adults from 2019 to 2020 was driven largely by uptake of newer agents within the class, including cladribine (3.2% of initiations in 2020), diroximel fumarate (6.7%) ozanimod (1.1%), and Siponimod (3.3%). Off-label therapies such as azathioprine, cyclophosphamide, mycophenolate, and rituximab, as well as initiations of mitoxantrone, were minimal (<2%) in adults throughout the study period.
In terms of children, trends in DMT initiations reflected trends in adults with 1 exception. As fingolimod’s use in adults decreased in adults after 2015, its use in children increased significantly through the end of the study period (P = .002). Between 2019 and 2020, fingolimod accounted for 68.8% of all initiation episodes in children.
"Trends in use of oral DMTs differed between adults and children in other ways as well. Initial uptake of oral DMTs was higher in children: by 2009, oral DMTs accounted for 5.7% of initiations in children but less than 0.1% of initiations in adults," the study authors noted. "However, subsequent uptake of oral DMTs appeared to be faster in adults than children: oral DMTs became the most commonly initiated DMTs in adults by 2013, 2 to 3 years before this occurred for children."
