SEATTLE – It is not clear if the greater reluctance among general neurologists to prescribe the drugs is hurting the health of patients, and the study does not examine whether general neurologists are referring their toughest patients to their subspecialist colleagues.
Still, the findings raise questions because “starting highly effective drugs early can prevent long-term disability,” said study lead author and neurologist Casey V. Farin, MD, a clinical fellow in the department of neurology at Duke University, Durham, N.C., who spoke in an interview prior to the presentation of the study findings at the annual meeting of the Consortium of Multiple Sclerosis Centers. “A lot of our general neurologists are prescribing the traditional platform therapies that have fallen a bit out of favor in the MS community,” she said.
Dr. Farin and colleagues launched their study to better understand whether “therapeutic inertia” is affecting how general neurologists treat MS. The term refers to “staying with one drug just because it is easier not to rock the boat,” she said. For the purposes of their study, the term encompasses reluctance of neurologists to escalate therapy or prescribe high-efficacy drugs.
“There have been small studies comparing subspecialists and general neurologists using surveys of theoretical cases,” she said. “No studies have looked at how people are prescribing disease-modifying therapy.”
In the new age of high-efficacy treatment, guidelines about early MS treatment are lacking. As the study abstract notes, “in the absence of robust head-to-head clinical data, neurologists do not have an accepted algorithm for initiation and escalation of therapy, although recent research indicates a benefit in initiating highly effective therapies early in the disease course.”
For the study, researchers tracked 4,753 patients with MS who were treated at the Duke University Health System from 2016 to 2018.
General neurologists prescribed platform therapies – interferons, glatiramer acetate (Copaxone) and dimethyl fumarate (Tecfidera) more often than did MS subspecialists (16% vs. 5%, P less than .0001, 12% vs. 6%, P = .001 and 31% vs. 11%, P less than .0001, respectively).
In regard to high-efficacy MS drugs, there was no significant difference in prescription rates of fingolimod (Gilenya) and natalizumab (Tysabri). But general neurologists were less likely to prescribe three other types than were general neurologists: Alemtuzumab (Lemtrada), ocrelizumab (Ocrevus) and rituximab (Rituxan) (0 vs. 8%, P = .0001, 3% vs. 27%, P less than .0001, and 2% vs. 7%, P = .0001, respectively).
Why might general neurologists be more resistant to embrace high-efficacy MS drugs? “They are newer and seen as more aggressive, and riskier,” Dr. Farin said. If general neurologists are not seeing many patients with MS and not prescribing these newer drugs very often, they may be more familiar with the older platform drugs, she said. “They may start with the ones that seem safer and are easier to start with.”
It is possible, she cautioned, that the study results may be confounded by general neurologists who refer patients to MS subspecialists when initial disease-modifying therapies fail.
No study funding was reported. Dr. Farin and two of the other four authors disclosed consulting fees from Biogen. No other disclosures were reported.
SOURCE: Farin CV et al. CMSC 2019. Abstract DXT44.