OBJECTIVES: Medication compliance with injectable disease-modifying treatments (DMTs) for multiple sclerosis (MS) is sub-optimal, with published compliance rates ranging from 27% to 83%. This study quantified MS patients’ preferences for features of injectable DMTs, and examined whether non-compliant patients have different preferences than compliant patients.
METHODS: Adults with self-reported physician-diagnoses of MS in Germany (N=189), the United Kingdom (UK) (N=100) and France (N=100) completed an online discrete choice experiment survey. Treatment-experienced respondents reported their level of compliance with their current (or most recent) MS medicine and two groups were created: compliant respondents (who reported always taking medicine exactly as prescribed) and non-compliant respondents (who reported missing less than half, about half, or more than half of doses). Respondents were presented with a series of nine treatment-choice questions wherein hypothetical treatments were described in terms of six attributes. Mixed-logit regression parameters were used to calculate preference weights, or utilities, of attribute levels and relative importance or, utility differences, of changes in attributes for both the compliant and non-compliant respondents. Wald- and t-tests of the differences in preferences were conducted.
RESULTS: In Germany, the UK and France, 81%, 37%, and 73% of the sample reported being compliant, respectively. The relative importance of delaying disability progression for 3 years was 2.7 times more important among the compliant group than the non-compliant group in Germany and the UK (P<0.05) and 1.1 times more important in France. Among compliant respondents, improvements in injection frequency (from 30 to 2 injections per month) relative to this improvement in efficacy were 1.5, 6.0, and 2.6 times more important to the non-compliant group than the compliant group in Germany, the UK, and France.
CONCLUSIONS: Reductions in injection frequency are relatively more important to non-compliant MS patients than to compliant patients, while delaying disability progression was relatively more important to compliant MS patients.
