BackgroundDisease modifying treatments (DMT) for MS such as interferon beta (IFNβ) have been shown to reduce the risk for disease progression. Therefore adherence to treatment is essential for treatment outcome.Here we want to evaluate if participation in a patient management program (PMP) improves adherence to DMT as well as health and cost outcomes associated with MS.MethodsIn this open-label multicentre prospective observational study, German MS patients treated with once weekly intramuscular (IM) IFNβ-1a (Avonex ®), were offered participation in a PMP and followed for up to 12 months. The PMP included injection trainings, support and quarterly visits for up to 12 months after initiation of therapy. Utilisation of health care services was evaluated.The primary endpoint was to evaluate the direct and indirect cost associated with MS from payer, patient and societal perspective, in patients who participate in the PMP. Secondary endpoint was the clinical outcome in patients who participate in the PMP (differentiated in adherent versus non-adherent patients).ResultsIn total 731 patients (mean age: 38.2, 73.7 % female) were enrolled, 640 (88 %) were observed for twelve months. After six months 34 % of patients had participated in the PMP continuously and 21 % temporarily; 39 % had not participated. After twelve months, the proportions of participants were: 37 % continuously and 19 % temporarily; 40 % had not participated.After 6 months, mean reduction in cost per patient in the participants group (€ 2151) was almost twice as high as the cost reduction amongst non-participants (€ 1131).After twelve months, the annual relapse rate was reduced by 58 % compared to baseline in both the participant and non-participant groups.ConclusionsIn a real-world-setting, participation in a patient management program was associated with improved medication adherence and lower total MS-related direct and indirect cost over time.