So far, it’s more like a ripple, according to a study of neurologists’ prescribing patterns. “The recently approved therapies will initially be niched as later-line options,” predicted Virginia R. Schobel, MSc, nephrology franchise head at Spherix Global Insights, an independent market intelligence firm in Exton, Pa.
At the virtual annual meeting of the Consortium of Multiple Sclerosis Centers, Ms. Schobel presented the results of a retrospective chart audit Spherix conducted in February 2020 of 1,006 patients with MS who were switched to a new DMT by 199 U.S. participating neurologists within the previous 3 months. About 72% of the switchers had relapsing remitting MS (RRMS).
Assessing the three new oral DMTs
The purpose of the study was to gain an understanding of the early adoption patterns for the three recently approved oral DMTs: siponimod (Mayzent), cladribine (Mavenclad), and diroximel fumarate (Vumerity).
The first surprise was that only 41% of medication switches to a new DMT among the RRMS group were to oral DMTs; that’s a substantially lower proportion than in prior Spherix chart audits. Instead, the most popular switch was to ocrelizumab (Ocrevus), a monoclonal antibody.
“Things to keep in mind when we see the switch shares for the newer products are just how crowded this market has become and how much Ocrevus has really changed the market,” Ms. Schobel explained in an interview. “Ocrevus has become increasingly dominant in the RRMS segment, so that now there are six oral DMTs competing among themselves for a relatively limited pool of patients.”
Because of grandfathering by the Food and Drug Administration, most of the oral DMTs now share identical indications for clinically isolated syndrome, RRMS, and active secondary progressive MS. Ocrevus, she noted, has the same indications.
Only 1% of MS patients who switched to a different DMT in late 2019 or early 2020 moved to diroximel fumarate. Three percent switched to siponimod, and another 3% switched to cladribine. Switches to the three older, established oral DMTs were collectively five times more common, with 15% of patients moving to dimethyl fumarate (Tecfidera), 11% to fingolimod (Gilenya), and 9% to teriflunomide (Aubagio).
Ms. Schobel said that the three latest oral DMTs offer advantages over the older ones in terms of various combinations of efficacy, dosing schedule, and/or tolerability, which may make them attractive options as first-line therapy. She predicted that, over time as neurologists gain increasing familiarity with these drugs as first line, they will also gradually become more comfortable in turning to them as switch options.
First-time switches to an oral DMT among patients with RRMS were most often made in search of improved efficacy. Neurologists cited this as their main reason for 73% of switches to cladribine and 36% of switches to teriflunomide, with the other oral agents falling at various points in between. A switch to fingolimod was most often driven by a wish for a high-efficacy DMT with once-daily oral dosing. Improved tolerability figured prominently in switches to teriflunomide, and even more so in the relatively few changes to diroximel fumarate.