[Safety and tolerability in the early phase of slow schedule versus fast schedule treatment with 44 micrograms of interferon beta-1a in patients with multiple sclerosis (PARALEN study)].

INTRODUCTION

Interferon (IFN) beta-1a, 44 micrograms, administered three times a week (tiw), is the recommended dose in 'relapsing' multiple sclerosis. During the clinical practice, physicians initiate treatment either with this complete dose, or with escalating dose.

AIM

To determine safety of IFN beta-1a 44 micrograms tiw, comparing a complete dose initiation regimen versus an escalating dose initiation.

PATIENTS AND METHODS

A total of 247 multiple sclerosis patients were enrolled in this study from 37 different Spanish centers, who initiated treatment with IFN beta-1a 44 micrograms tiw. Safety and tolerability was compared in patients switching from other previous interferon to a direct complete dose regime of IFN beta-1a 44 micrograms tiw vs. an escalating dose regime in naive multiple sclerosis patients.

RESULTS

Adverse events were more frequent when administrating interferon in a 'fast-regime' directly with a complete dose.

CONCLUSIONS

An escalating dose with IFN beta-1a 44 micrograms tiw is recommended to initiate treatment in multiple sclerosis patients. In patients previously treated with another interferon beta, a complete dose regime initiation can be also scheduled, without significant differences in the reporting of adverse events.