Protocol Amendment 1, dated 06 Oct 2009, provided the following key changes. Based on the date of the amendment, 8 subjects were enrolled globally at the time of the amendment. • The study was conducted only in countries in which LCM was commercially available at the time of study completion; therefore, reference to the fact that LCM was to be provided according to local laws where not commercially available was removed because it was no longer applicable • The liver function test (LFT) withdrawal criteria were revised to reflect the Sponsor’s current understanding of the safety profile of LCM based on a comprehensive review of the data from clinical studies • The AEs of special interest were revised to reflect the Sponsor’s current understanding of the potential risks of LCM based on a comprehensive review of the data from clinical studies and commitments to regulatory agencies • The approach to detect safety signals was clarified to reflect the Sponsor’s current practice • Other changes made in this amendment were minor or administrative

Protocol Amendment 2, dated 09 Jul 2010, provided the following key changes. Based on the date of the amendment, 111 subjects were enrolled globally at the time of the amendment. • The inclusion criteria were revised to reflect the minimum age of eligible subjects in various countries and regions of the world. In addition, the inclusion criterion for newly diagnosed subjects in the First Add-On Group was updated to clarify that subjects were taking adequate monotherapy and to define what was considered adequate monotherapy for the purpose of this study. The maximum period for the time between the epilepsy diagnosis and the Screening Visit of the First Add-On Group was extended to 24 months in order to better reflect adjunctive therapy in clinical practice • Exclusion criteria were amended to exclude subjects with cranial surgery within the last year prior to the study. Cranial surgery indicated the presence of acute or unstable neurological disorders, which were exclusionary per protocol • Visit windows for titration phone calls were updated to allow for a variation in time of ±1 day relative to Visit 2 • Other changes made in this amendment were minor or administrative

Protocol Amendment 3, dated 14 Dec 2010, was a substantial amendment and provided the following key changes. Based on the date of the amendment, 242 subjects were enrolled globally at the time of the amendment. • An exclusion criterion was added for known sodium channelopathy. The decision to exclude subjects with known channelopathies, such as Brugada syndrome, from clinical studies with LCM was based on a Food and Drug Administration (FDA) recommendation (17 Aug 2010). The basis for this recommendation was a theoretical concern that enhanced slow inactivation of sodium channels by LCM may have been proarrhythmic in subjects with sodium channelopathies • Revisions were made to withdrawal criteria and follow-up recommendations for abnormal LFTs based on the following: o Newly adopted FDA Guidance for Industry on drug-induced liver injury, which went into effect in Jul 2009, and a recommendation from the FDA to reinsert previously included wording regarding additional withdrawal criteria and follow-up recommendations for abnormal LFTs in LCM protocols o Although no new liver-related safety issues with LCM had been identified, LFT abnormal was added as a postmarketing adverse drug reaction in the LCM Company Core Data Sheet and the EU Summary of Product Characteristics; therefore, LCM protocols were amended to reflect this addition With these revisions, liver-related safety signals continued to be detected via protocol-directed monitoring and additional follow up in ongoing and future LCM clinical studies

Protocol Amendment 4, dated 11 Jul 2011, was a substantial amendment and provided the following key changes. Based on the date of the amendment, 401 subjects were enrolled globally at the time of the amendment. The changes in Protocol Amendment 4 only affected subjects in the First Add-On Group because the Later Add-On Group’s enrollment was closed prior to the amendment’s approval in any of the countries. • The Sponsor’s name was changed to UCB BIOSCIENCES, INC. Specific Sponsor contact information was updated, and the US phone numbers for reporting serious adverse events (SAEs) were revised. The name and address of the study medication supplier was updated • Switzerland was added as a participating country, with the inclusion criterion being revised to reflect the minimum age of eligible subjects from this country • The inclusion criterion defining the minimum allowed seizure frequency was revised to ≥3 partial-onset seizures (IA, IB, or IC) at any time during the 3 months prior to the Screening Visit from ≥1 partial-onset seizure (IA, IB, or IC) per 28 days. This change did not reflect a change in the number of seizures required in the 3 months prior to Screening, just a change in the frequency per month

• In addition, the inclusion criterion defining the amount of time that a subject had to be on a stable AED dose regimen and concurrent stable vagus nerve stimulation (VNS) prior to Screening was reduced from 28 days to 7 days to accommodate the First Add-On Group subjects who may have required more frequent AED dose changes in clinical practice than the Later Add-On Group subjects • In accordance with the FDA Draft Guidance for Industry on suicidality (Suicidality: Prospective assessment of occurrence in clinical trials), which went into effect on 29 Oct 2010, the Columbia-Suicide Severity Rating Scale ([C-SSRS] Columbia University Medical Center, 2008) was added to all ongoing and new interventional protocols in order to prospectively assess the occurrence of treatment-emergent suicidality in clinical studies of drug and biological products (FDA, Draft Guidance for Industry 2010) • A list of anticipated SAEs was included in this amendment in compliance with the FDA Guidance for Industry and Investigators on safety reporting requirements for studies conducted under an open Investigational New Drug Application (Safety reporting requirements for IND and BE/BA studies), which went into effect on 28 Mar 2011 (FDA, Guidance for Industry and Investigators, 2010) • Other changes made in this amendment were administrative in nature