Phase 2 Efficacy, Safety, and Tolerability Study of Natalizumab in Focal Epilepsy

Key Inclusion Criteria:

- Must have focal epilepsy diagnosed on clinical grounds and as applicable supported by
electroencephalogram findings [Scheffer 2017] and brain imaging. Participants with
multifocal epilepsy may be included if all other entry criteria are met.

- Must have a drug-resistant epilepsy defined as failure of adequate trials of 2 (or
more) tolerated and appropriately chosen and used AEDs (whether as monotherapies or in
combination) [Kwan 2010].

- Experiences 6 or more seizures during the 6-week prospective baseline period and is
not seizure free for more than 21 consecutive days during the prospective baseline
period

Key Exclusion Criteria:

- Focal aware seizures without motor signs are the only seizure type.

- Diagnosis of generalized, combined generalized and focal, or unknown epilepsy

- Known progressive structural CNS lesion.

- History of seizures occurring in predominantly clustered patterns, as determined by
the Investigator, over the 12 months prior to the Screening Visit (Week -6) or during
the 6-week prospective baseline period, where individual seizures cannot be counted.

- History of status epilepticus within the previous 6 months.

- Known history or presence of non-epileptic seizures.

NOTE; Other protocol defined Inclusion/Exclusion criteria may apply