An Observational Study of Multiple Sclerosis (MS) Patients Starting or Restarting Baseline Treatment With Interferon Beta 1a After the Use of Escalation Treatment With Mitoxantrone (RETURN)

The treatment of relapsing-remitting MS with interferon-beta has established itself as first-choice treatment. In previous clinical studies, the interferon-beta 1a (Rebif) used within the scope of this PMS study has demonstrated significant efficacy in all aspects of treatment - magnetic resonance imaging (MRI) data, relapse rate, progression of disability of MS. The PRISMS-4 study demonstrated that treatment with Rebif reduces the frequency and severity of clinical relapses over 4 years and slows the progression of disability.

In the course of treatment escalation according to the Multiple Sklerose Therapie Konsensus Gruppe (MSTKG) guidelines, MS subjects with correspondingly high disease activity were predominantly put on mitoxantrone. The duration of treatment is on principle limited by a cumulative lifelong total dose of 140 mg/m2 body surface area, which may not be exceeded due to the known cardiologic adverse effects. If the cumulative mitoxantrone maximum dose is reached and if the subject is in a stable condition, the question of further treatment options presents itself. One possibility is the so-called 'deescalation', that is, the return to immunomodulating baseline treatment.

Currently there is an increasing number of subjects who are in this phase of the disease and are eligible for corresponding treatment decisions.

OBJECTIVES

Primary objective:

• To systematically investigate the safety, benefit and course of Rebif (44 μg x 3 ),treatment in a larger number of subjects and to subject these data to standardized analysis