Comparative study of the pharmacodynamic and pharmacologic effects of Betaseron (R) and AVONEX (TM)

The aim of this 1 week study was to compare the biologic effects induced by Betaseron(R) and AVONEX(TM) using their approved dose, route, and schedule . Sixteen healthy volunteers were randomly assigned to receive either a sin gle i.m. dose of AVONEX(TM) (6 million International Units [MIU]) or, every other day s.c. doses of Betaseron(R) (8 MIU). Common side effects associat ed with interferon-beta (IFN-beta) treatment and biologic response paramete rs (neopterin, beta(2)-microglobulin, interleukin-10 [IL-10], and MxA prote in levels in blood) were measured. Ibuprofen was administered to all subjec ts throughout the study. Fever, chills, and myalgia occurred most frequentl y and with the greatest severity between 6 and 12 h after the first dose of either IFN-beta. Despite the additional dosing of subjects in the Betasero n(R) group, the incidence, duration, and severity of the side effects were not significantly different from those in the AVONEX(TM) group. Biologic re sponse parameters reached similar maximum concentrations in both treatment groups. In the Betaseron(R) group, neopterin and beta(2)-microglobulin leve ls remained significantly greater than baseline throughout the 7 day study, whereas those in the AVONEX(TM) group were elevated only through day. Beta seron(R) treatment significantly increased IL-10 levels above baseline, but AVONEX(TM) treatment did not. The overall induction of neopterin, beta(2)- microglobulin, and IL-10 (as measured by area under the concentration-time curve) was significantly greater in the Betaseron(R) group than the AVONEX( TM) group (p = 0.031). The results of this study demonstrate that the appro ved Betaseron(R) dosing regimen, in combination with ibulprofen use, provid ed a significantly greater and more consistently elevated biologic response compared with that of AVONEX(TM) and did so with a side effects profile co mparable to that of once a week AVONEX(TM) dosing.