Srinivas G. Rao

The Efficacy and Safety of Milnacipran for Treatment of Fibromyalgia. A Randomized, Double-blind, Placebo-controlled Trial

Objective. To evaluate the safety and efficacy of milnacipran, a dual norepinephrine and serotonin reuptake inhibitor, in the treatment of fibromyalgia (FM). Methods. A 27-week, randomized, double-blind, multicenter study compared milnacipran 100 and 200 mg/day with placebo in the treatment of 888 patients with FM. Two composite responder definitions were used to classify each patient’s individual response to therapy. “FM responders” concurrently satisfied response criteria for improvements in pain (visual analog scale 24-h morning recall), patient global impression of change (PGIC), and physical functioning (SF-36 Physical Component Summary); while “FM pain responders” concurrently satisfied response criteria for improvements in pain and PGIC. Results. At the primary endpoint, after 3-month stable dose treatment, a significantly higher percentage of milnacipran-treated patients met criteria as FM responders versus placebo (milnacipran 200 mg/day, p = 0.017; milnacipran 100 mg/day, p = 0.028). A significantly higher percentage of patients treated with milnacipran 200 mg/day also met criteria as FM pain responders versus placebo (p = 0.032). Significant pain reductions were observed after Week 1 with both milnacipran doses. At 15 weeks, milnacipran 200 mg/day led to significant improvements over placebo in pain (realtime, daily and weekly recall; all measures, p < 0.05), PGIC (p < 0.001), fatigue (p = 0.016), cognition (p = 0.025), and multiple SF-36 domains. Milnacipran was safe and well tolerated by the majority of patients during 27 weeks of treatment; nausea and headache were the most common adverse events. Conclusion. Milnacipran is safe and effective for the treatment of multiple symptoms of FM.

Milnacipran: A comparative analysis of human monoamine uptake and transporter binding affinity

BACKGROUND Though selective serotonin reuptake inhibitors have revolutionized the field of psychiatry with demonstrated efficacy in affective and anxiety disorders with minimal side effects, norepinephrine-serotonin reuptake inhibitors may provide efficacy similar to tricyclic antidepressants without the adverse side effects associated with tricyclic antidepressants. METHODS The affinity and selectivity of milnacipran, duloxetine, venlafaxine, citalopram, amitriptyline, and nortriptyline were determined for the human serotonin, norepinephrine, and dopamine transporters. RESULTS Both milnacipran and duloxetine were potent inhibitors of serotonin and norepinephrine uptake. Unlike duloxetine and venlafaxine, milnacipran appears serotonin transporter selective in binding (ratio = 2.61) and norepinephrine transporter selective in uptake (ratio =.45). CONCLUSIONS Milnaciprans binding and uptake inhibition profile more closely resembles that of the tricyclic antidepressants than that of duloxetine. Whether these differences observed in vitro manifest themselves in vivo is not clear.