Assessing Efficacy and Safety of Lacosamide Compared to Placebo in Reducing Signs and Symptoms of Fibromyalgia Syndrome.

This was a proof-of-concept study and not powered for statistical comparisons.

The trial consisted of a 4-week Titration Phase, an 8-week Maintenance Phase, a 1-week Taper Phase, and a 2-week Safety Follow-Up Phase. If subjects met the eligibility criteria, they were randomized to receive either lacosamide 400mg/day or placebo during the Maintenance Phase. Subjects assigned to lacosamide were titrated from 100mg/day to 400mg/day at weekly intervals of 100mg. All subjects who completed the 4-week Titration Phase entered an 8-week Maintenance Phase. No dose adjustment was allowed during the Maintenance Phase. The Treatment Phase was defined as the combined Titration and Maintenance Phases.

Inclusion criteria

• Males or females, 18 to 65 years old
• Fulfills all 3 points of American College of Rheumatology (ACR) definition for diagnosis of fibromyalgia
• At least moderate pain (pain intensity ≥ 5 on Likert pain scale (0-10) during the 7 days prior to Baseline)
• Fibromyalgia Impact Questionnaire (FIQ) total score ≥ 50
• Completed an adequate washout period for excluded medications prior to beginning the Baseline Diary Phase

Exclusion criteria

• Symptomatic regional or structural rheumatic disease
• Diagnosed neuropathic pain syndrome
• Receiving treatment with neurostimulating devices
• Significant psychopathology
• History of chronic alcohol or drug abuse within 6 months prior to Screening
• Been hospitalized for psychiatric or behavioral reasons within 6 months prior to Screening
• Clinically significant abnormal vitals, cardiac dysfunction and /or arrhythmias
• Taken neuroleptics, serotonin and norepinephrine reuptake inhibitors (SNRIs) or tricyclic antidepressants (TCAs)
• Other medical conditions that could compromise the subject's ability to participate in the study