We conducted a comprehensive review of selected adverse event reports
that were submitted to the Food and Drug Administration (FDA) for inte
rferon beta-1b during the first 30 months following licensure. The adv
erse events reviewed were injection site reactions, injection site nec
roses, and non-injection site necroses. These adverse events were sele
cted because of the relative frequency of injection site reactions and
because of the severity and sequelae of certain injection site and no
n-injection site necroses. Our review enabled us to characterize the c
linical presentation and the treatment received, which were not descri
bed in the package insert or by the IFNB (interferon beta-1b) Multiple
Sclerosis Study Group Publication. The time of onset of the adverse e
vents ranged from I - 29 months after initiation of interferon beta-1b
treatment, with a mean of 1 month. In general, the more clinically si
gnificant adverse events (i.e., injection site necrosis and non-inject
ion site necrosis) developed more slowly than the injection site react
ions. Greater than 85% of the adverse events presented with one or two
signs/symptoms, although the number of signs/symptoms ranged from I -
8. No predominance of treatments for the adverse events was observed.
The most striking finding was that the overall sex ratio, which could
be due to reporting artifacts, was 8.1:1 female:male.