ADVERSE REACTIONS1

MOST COMMON ADVERSE REACTIONS IN THE AFFIRM TRIAL1
Incidence ≥10% with TYSABRI and ≥2% difference with placebo TYSABRI
n=627
Placebo
n=312
Headache 38% 33%
Fatigue 27% 21%
Infusion reactionsa 24% 18%
Urinary tract infections 21% 17%
Arthralgia 19% 14%
Depression 19% 16%
Pain in extremity 16% 14%
Rash 12% 9%
Gastroenteritis 11% 9%
Vaginitisb 10% 6%

aInfusion reactions were defined as any event that occurred within 2 hours after the start of the infusion.
bPercentage based on female patients only.

MOST COMMON SERIOUS ADVERSE REACTIONS IN THE AFFIRM TRIAL1
  TYSABRI
n=627
Placebo
n=312
Infections 3.2% 2.6%
Urinary tract infection 0.8% 0.3%
Pneumonia 0.6% 0%
Acute hypersensitivity reactions 1.1% 0.3%
Anaphylaxis/
anaphylactoid reaction
0.8% 0%
Depression 1.0% 1.0%
Suicidal ideation
or attempt
0.6% 0.3%
Cholelithiasis 1.0% 0.3%