Study Finds Patients with Multiple Sclerosis Are Highly Persistent with DMT

With the accumulation of safety and effectiveness data for disease-modifying therapies (DMT) and the rapid pace of new drug approvals in this category for multiple sclerosis (MS) indications, treatment patterns are inevitably changing.

However, Clyde E. Markowitz, MD, and colleagues reported during a poster presentation at the American Academy of Neurology (AAN) 2013 Annual Meeting that many patients stick with the disease modifying therapy (DMT) they were originally prescribed.

Clyde E. Markowitz, MD, is Director of the Multiple Sclerosis Center at the Hospital of the University of Pennsylvania, and associate professor of neurology at the University of Pennsylvania School of Medicine in Philadelphia.

In this presentation, during the “Multiple Sclerosis: Cost and Impact of MS Care” session, Markowitz reported on an assessment of therapy usage and treatment patterns over three years of follow-up in the Therapy Optimization in Multiple Sclerosis Study (TOP MS).

Potential participants for TOP MS, a prospective, observational study, were identified at selected specialty pharmacies beginning in December 2008. Enrollees had a MS diagnosis; half were being treated with glatiramer acetate (GA) and half with an interferon beta (IFN) dispensed by a participating specialty pharmacy. Signed informed consents were returned to the patients’ respective pharmacies. At study enrollment, qualified subjects received log-on instructions for the study website where responses were entered. DMT use was assessed each month, along with persistence, drug holidays, therapy changes (including discontinuation), and reasons for therapy changes.

Of the 2,530 participants with a minimum of one year of follow-up, 2,293 (90.6%) continued to use the same DMT. More users of GA than IFN persisted on therapy (Chi square 19.4; p < 0.004). Among those who persisted, 24 patients took drug holidays averaging 2.4 months (most often for financial reasons or common side effects) before resuming their DMT. Those who discontinued their initial DMT stopped for similar reasons, including loss of insurance coverage, intolerable injection site reactions, or ineffectiveness of therapy.

There were 172 therapy changes among 156 patients (6.2%): 32.6% of the changes originated with GA while 65.6% of the changes originated with IFN. Nearly 50% of DMT changes were to the newer therapies (natalizumab, INF beta-1b [Extavia], fingolimod), while 29% switched to IFN and 22% to GA. The predominant reasons for changing therapies were ineffectiveness, worsening of symptoms, and the doctor’s preference for a different medication.

Markowitz drew the conclusion from this study that persistence on the same DMT is high among patients on therapy for a year or more. Furthermore, for those patients changing their therapy, there was a marked shift in prescribing toward the newer therapies in response to signs of worsening symptoms or due to an unspecified physician preference for a different medication.