Multiple Sclerosis (MS) Patient Adherence to Delayed-Release Dimethyl Fumarate and Patient Reported Side Effects from a Specialty Pharmacy Program

Background: Biogen Idec’s delayed-release dimethyl fumarate (DMF; also known as gastro-resistant DMF; TECFIDERA^®) oral medication to treat MS became available in March 2013 for relapsing forms of MS.  Walgreens Connected Care^SM for MS (CCMS) program provides enhanced management and care for patients taking DMF including assessments of patient reported side-effects and related information. Limited real world evidence is currently available for MS patients taking DMF.

Objectives: The main objective was to describe 6 and 12 month adherence levels, after controlling for other factors.  A secondary objective was to describe the prevalence of patient reported side effects.

Methods: Adherence was measured using PDC (proportion of days covered) for a 6 or 12 month follow-up period.  Patient reported side effects were collected through the CCMS telephonic assessments.  5,279 patients were at least 18 years of age and initiated therapy from April 2013 to December 2013, and followed through June 2014.

Results: The demographic profile of patients was similar to the national MS population.  Median PDC for the 3,319 patients with six full months of data was 92.9% (range 16.5-100).  For these patients, adherence to other MS medications utilized prior to DMF was  90.1%; (range 1.7-100).   For the 1,216 patients with 12 months of data, the median PDC was 82.2% (range 10.1-100).  214 (4.0%) patients switched from DMF to another DMT within 12 months; the proportion was significantly lower among patients reporting no side effects (P < 0.02).  4,179 patients were asked at least one side effect question.  The most common response was none (1,830 or 43.8%), followed by reports of flushing (1,790 or 42.9%) and abdominal pain (698 or 16.7%).  For assessed patient relapse within the last 30 days, 107 reported a relapse (2.6%) after the first 62 days of therapy through end of study.

Conclusions: In the first year post approval, the 6-month adherence rates for patients utilizing DMF were equivalent to those of other patients treated with a DMT prior to starting DMF. As observed with other chronic medication use, adherence was lower at 12 months.  Adherence was influenced by patient characteristics and length of CCMS participation.  Rates of patient-reported side effects were comparable to those seen in clinical trials, and the percentage of patients reporting no side effects (43.8%) was higher than that reported in the clinical literature.