Milnacipran Improves Pain, Other Symptoms of Fibromyalgia
Daniel Clauw, MD, from the University of Michigan, Ann Arbor, and colleagues analyzed the influence of baseline pain and symptom severity on the efficacy of milnacipran. Data were pooled from three similarly designed, double-blind, placebo-controlled trials in which patients were randomized to placebo (n=1,333), milnacipran 100mg/day (n=1,139), or milnacipran 200mg/day (n=837).
Efficacy assessments were measured by pain responder analysis (≥30% improvement from baseline in visual analog scale (VAS) 24-hour recall pain scores), Patient Global Impression of Change (PGIC) responder analysis (1=very much improved, 2=much improved), and a two-measure composite responder analysis (individual patients were required to meet both pain and PGIC responder criteria). Data were stratified by baseline pain (VAS score <60 [moderate pain]; ≥60–70 [severe pain]; >70 [very severe pain]) or fibromyalgia severity (Fibromyalgia Impact Questionnaire [FIQ] total score <39 [mild]; 39–<59 [moderate]; ≥59 [severe]). Results were reported for observed cases at the three-month endpoint.
Milnacipran treatment resulted in significantly greater pain, PGIC, and two-measure responder rates regardless of baseline pain severity group when compared with placebo (P<0.05 for milnacipran 100mg and P<0.001 for milnacipran 200mg; OR 1.7–2.5 for pain responders; 1.7–2.8 for PGIC responders; 1.5–3 for two-measure responders).
Similarly, in all baseline FIQ severity subgroups, pain, PGIC, and 2-measure responder rates were significantly greater with milnacipran treatment vs. placebo (P<0.05, both doses; OR 1.6–3 for pain responders; 1.8–4 for PGIC responders; 1.8–3.2 for two-measure responders), except in the small group of patients with an FIQ total score <39 for 100mg/day 2-measure composite responders (n=42; OR 2.2) and 200mg/day pain responders (n=26; OR 1.7).