Partial (Type I) Seizures can be classified into one of the following three groups: Simple Partial Seizures, Complex Partial Seizures, Partial Seizures evolving to Secondarily Generalized Seizures.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

Responders are those subjects with at least 50 % reduction from Baseline to Treatment Period in Partial Onset Seizure frequency per week.

The Responder Rate for Partial Onset Seizures (Type I) is the proportion of subjects who have a >= 50 % reduction in seizure frequency per week from Baseline.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

There are three types of Epilepsy: Partial Epilepsies (Type I), Generalized Epilepsies (Type II) and uncertain classification of Epilepsies (Type III).

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The percent change from Baseline was computed as: Weekly Seizure Frequency (Treatment) - Weekly Seizure Frequency (Baseline) / Weekly Seizure Frequency (Baseline) * 100. Negative values indicate a reduction from Baseline with higher negative values showing higher reduction.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The categories are:

• <= 25 %
• - 25 % to < 25 %
• 25 % to < 50 %
• 50 % to < 75 %
• 75 % to < 100 %
• 100 %

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

Subjects were considered seizure free if their seizure counts for every day over the entire Treatment Period was zero and if they completed the Treatment Period.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The time to first Type I Seizure during the 12-week Treatment Period was measured in days.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The time to Fifth Type I Seizure during the 12-week Treatment Period was measured in days.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The time to tenth Type I Seizure during the 12-week Treatment Period was measured in days.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

The type IC/Type I seizure frequency ratio is represented by the percentage of subjects having a reduction in the ratio of Type IC seizure frequency over Type IA, IB, and IC seizure frequency from Baseline to Treatment Period.

The Intention-to-treat (ITT) population was defined as all randomized subjects who received at least 1 dose of study medication.

Type IC Population consists of those subjects with at least one Type IC seizure during the Baseline period.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-To-Treat (ITT) population with measurements at Baseline and Last Visit / Early Discontinuation.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-To-Treat (ITT) population with measurements at Baseline and Last Visit / Early Discontinuation.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit / Early Discontinuation.

The Hospital Anxiety and Depression Scale (HADS) was used to evaluate anxiety and depression simultaneously. The HADS was developed as a self-administered scale that has been designed to assess the presence and severity of both anxiety and depression. It consists of 14 items that are scored on a 4-point severity scale ranging from 0 to 3. A score per dimension was calculated with each score ranging from 0 to 21 and higher scores indicating higher depression / anxiety. Negative values in Change from Baseline indicate a decrease of HADS from Baseline to Treatment Period.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit / Early Discontinuation.

The Hospital Anxiety and Depression Scale (HADS) was used to evaluate anxiety and depression simultaneously. The HADS was developed as a self-administered scale that has been designed to assess the presence and severity of both anxiety and depression. It consists of 14 items that are scored on a 4-point severity scale ranging from 0 to 3. A score per dimension was calculated with each score ranging from 0 to 21 and higher scores indicating higher depression / anxiety. Negative values in Change from Baseline indicate a decrease of HADS from Baseline to Treatment Period.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit / Early Discontinuation Visit.

The Patient's Global Evaluation Scale (P-GES) is a global assessment of the disease evolution which was performed using a seven-point scale (1 = Marked worsening to 7 = Marked improvement) with the start of the study medication as the reference time point. The subject not mentally impaired had to complete it by answering the following question: "Overall, has there been a change in your seizures since the start of the study medication?"

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The Investigator's Global Evaluation Scale (I-GES) is a global assessment of the disease evolution which was performed using a seven-point scale (1 = Marked worsening to 7 = Marked improvement), with the start of the study medication as reference time point. The Investigator was to complete it by answering the following question: "Assess the Overall change in the severity of patient's illness, compared to start of study medication."

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.

The QOLIE-31-P is an adaptation of the original QOLIE-31 instrument that includes 30 items grouped into seven multi-item subscales - Seizure Worry (5 items), Overall Quality of Life (2 items), Emotional Well-Being (5 items), Energy/Fatigue (4 items), Cognitive Functioning (6 items), Medication Effects (3 items) and Daily Activities/Social Functioning (5 items) - and a Health Status item. The subscale scores, the Total score and the Health Status item score are calculated according to the scoring algorithm defined by the author with scores ranging from 0 to 100 and higher scores indicating better function. A positive value in Change from Baseline indicates an improvement from Baseline.

Subjects in the Intention-to-treat (ITT) population with measurements at Baseline and Last Visit or Early Discontinuation Visit.