Clinical Drug Investigation

, Volume 21, Issue 4, pp 307–318

Interferon-Beta in the Treatment of Multiple Sclerosis

Do Clinical Data Support the Existence of a Ceiling Effect?
Clinical Review

DOI: 10.2165/00044011-200121040-00009

Cite this article as:
Clanet, M. Clin. Drug Investig. (2001) 21: 307. doi:10.2165/00044011-200121040-00009


Three interferon-beta (IFNβ) products (Betaferon®, Avonex® and Rebif®) have been shown to be effective in the treatment of relapsing forms of multiple sclerosis, but the optimal dose of each product has not been established. The lack of head-to-head trials comparing the different IFNβs directly has led to comparisons across clinical trials, despite known limitations of such an approach (e.g. differences between studies with regard to patients studied, design, duration and end-point definitions). Furthermore, IFNβ preparations are manufactured and formulated differently and are delivered by different routes of administration; they are thus different with respect to their bioavailability, immunogenicity and specific activities. Nevertheless, the results of a manual review of all major published dose-comparison studies on IFNβ preparations suggest that there may be a dose-response effect below a certain threshold dose for each product. However, once this threshold dose is attained, a ceiling effect exists; higher doses do not provide added clinical benefit, but may be associated with a higher incidence of adverse events. Hence, physicians should weigh the lack of additional clinical benefits of higher IFNβ doses with the increased risk of adverse events when deciding on the appropriate dose of IFNβ for their patients.

Copyright information

© Adis International Limited 2001

Authors and Affiliations

  1. 1.Federation de NeurologieCHU Toulouse Purpan, Place du Doctor Center BaylacToulouseFrance