TYSABRI Global Observational Program in Safety

TYGRIS: TYSABRI® Global Observational Program in Safety

The Primary objective of this study is to determine the incidence and pattern of serious infections, malignancies, and other serious adverse events (SAE) in participants with multiple sclerosis (MS) treated with Tysabri (natalizumab).

The TYSABRI Global Observational Program in Safety (TYGRIS) is a safety observational cohort program designed to obtain long-term safety data in multiple sclerosis (MS) participants treated with natalizumab in a clinical practice setting in the United States or Canada.

Key Inclusion Criteria:

• MS patients in the US and Canada receiving TYSABRI under standard clinical care for less than or equal to 3 infusions are eligible to participate in TYGRIS.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.