Effects of levomilnacipran ER on fatigue symptoms associated with major depressive disorder

The clinical utility of newer antidepressant agents: Understanding the role in management of MDD

Whereas MDD is characterized in part by changes in mood, other symptoms can also cause significant impairment, including sexual dysfunction, cognitive impairment, and fatigue. Newer antidepressants are explored with the goal of more optimally treating these non–mood-related symptoms of MDD. The 3 oral antidepressants that have been FDA-approved most recently include vortioxetine, vilazodone, and levomilnacipran. Unique features of these antidepressants are explored through 3 patient cases.

Dysfunction in Serotonergic and Noradrenergic Systems and Somatic Symptoms in Psychiatric Disorders

Somatic symptoms include a range of physical experiences, such as pain, muscle tension, body shaking, difficulty in breathing, heart palpitation, blushing, fatigue, and sweating. Somatic symptoms are common in major depressive disorder (MDD), anxiety disorders, and some other psychiatric disorders. However, the etiology of somatic symptoms remains unclear. Somatic symptoms could be a response to emotional distress in patients with those psychiatric conditions. Increasing evidence supports the role of aberrant serotoninergic and noradrenergic neurotransmission in somatic symptoms. The physiological alterations underlying diminished serotonin (5-HT) and norepinephrine (NE) signaling may contribute to impaired signal transduction, reduced 5-HT, or NE release from terminals of presynaptic neurons, and result in alternations in function and/or number of receptors and changes in intracellular signal processing. Multiple resources of data support each of these mechanisms. Animal models have shown physiological responses, similar to somatic symptoms seen in psychiatric patients, after manipulations of 5-HT and NE neurotransmission. Human genetic studies have identified many single-nucleotide polymorphisms risk loci associated with somatic symptoms. Several neuroimaging findings support that somatic symptoms are possibly associated with a state of reduced receptor binding. This narrative literature review aimed to discuss the involvement of serotonergic and noradrenergic systems in the pathophysiology of somatic symptoms. Future research combining neuroimaging techniques and genetic analysis to further elucidate the biological mechanisms of somatic symptoms and to develop novel treatment strategies is needed.

Fatigue in Patients with Major Depressive Disorder: Prevalence, Burden and Pharmacological Approaches to Management

Fatigue is a frequently reported symptom in major depressive disorder, occurring in over 90% of patients. Clinical presentations of fatigue within major depressive disorder encompass overlapping physical, cognitive and emotional aspects. While this review addresses the epidemiology, burden, functional impact and management of fatigue in major depressive disorder, the main focus is on available pharmacotherapy options and their comparative efficacies. Our review of the effects of pharmacological treatments on fatigue in major depressive disorder found that medications with dopaminergic and/or noradrenergic action such as modafinil, flupenthixol and atomoxetine were most effective in improving symptoms of fatigue and low energy. However, significant variation across studies in assessment tools and study inclusion/exclusion criteria may have contributed to inconsistent findings. The efficacy of non-pharmacological interventions is also discussed, including light therapy and exercise.

Efficacy and tolerability of different doses of three new antidepressants for treating major depressive disorder: A PRISMA-compliant meta-analysis

In last decade, the US FDA has approved three new antidepressants: vortioxetine, levomilnacipran, and vilazodone. Many studies have researched the effects of these antidepressants on major depressive disorder (MDD), but they have not determined the optimum dosage. This meta-analysis investigated the efficacies of these three drugs at different dosages in the treatment of MDD. The PubMed, Embase, Cochrane Library, psycINFO, and ClinicalTrials.gov databases were searched to identify relevant literature. The primary outcomes were efficacy [quantified as the change from baseline in total score on the Montgomery-Asberg Depression Rating Scale (MADRS)] and tolerability (discontinuations due to adverse events). The effect size was quantified as the weighted mean difference for continuous data and the risk ratio (RR) for dichotomous data. Overall 22 studies were included. The changes in the MADRS total score were significantly higher for vortioxetine at 5, 10, 20, and 10-20 mg/day than for placebo. The tolerability was significantly worse for 20 mg/day vortioxetine than for placebo (RR = 1.84, 95% confidence interval = 1.13 to 3.02). In addition, increasing the dosage improved the efficacy of vortioxetine but worsened the tolerability. Levomilnacipran and vilazodone at any dosage produced a significantly higher mean change from baseline in the MADRS total score and a worse tolerability than for placebo. In conclusion, considering both efficacy and tolerability, 10 mg/day vortioxetine might be optimal for the treatment of MDD. The long-term efficacy and safety of vortioxetine needed to be investigated, and more studies of levomilnacipran and vilazodone are needed to define their optimal dosages.

The impact of fatigue and energy on work functioning and impairment in patients with major depressive disorder treated with desvenlafaxine

Fatigue and low energy are cardinal symptoms of major depressive disorder (MDD) that have an impact on work functioning. Antidepressants with noradrenergic activity have been hypothesized to improve symptoms of fatigue and low energy. We examined the impact of these symptoms on work functioning in patients with MDD treated with the serotonin and noradrenaline reuptake inhibitor, desvenlafaxine. A secondary analysis was carried out from a study of employed adult outpatients (n=35) with MDD and subjective cognitive complaints treated with desvenlafaxine 50-100 mg/day for 8 weeks. Multiple regression analyses modeled improvement in work functioning measures (Lam Employment Absence and Productivity Scale, Health and Work Performance Questionnaire, Sheehan Disability Scale) with measures of fatigue (Patient-Reported Outcomes Measurement Information System Fatigue scale and 20-item Hopkins Symptom Check List Energy scale). Patients showed a significant improvement in Montgomery-Åsberg Depression Rating Scale scores as well as in fatigue and work functioning measures following treatment. Fatigue measures were significantly associated with improvement in some (Lam Employment Absence and Productivity Scale, Sheehan Disability Scale), but not all (Health and Work Performance Questionnaire) work functioning measures, independent of improvement in overall depressive symptoms. The limitations of this study include the small sample size and the lack of a placebo or a comparison group. Fatigue and low energy are important symptoms that are associated with occupational impairment in MDD. Treatments that improve these symptoms are likely to improve work functioning.

Effects of levomilnacipran ER on noradrenergic symptoms, anxiety symptoms, and functional impairment in adults with major depressive disorder: Post hoc analysis of 5 clinical trials

OBJECTIVE

To evaluate the effects of levomilnacipran extended-release (LVM-ER; 40-120mg/day) on noradrenergic (NA) and anxiety-related symptoms in adults with major depressive disorder (MDD) and explore the relationship between these symptoms and functional impairment.

METHODS

Data were pooled from 5 randomized, double-blind, placebo-controlled trials (N=2598). Anxiety and NA Cluster scores were developed by adding selected item scores from the Montgomery-Åsberg Depression Rating Scale (MADRS) and 17-item Hamilton Depression Rating Scale (HAMD₁₇). A path analysis was conducted to estimate the direct effects of LVM-ER on functional impairment (Sheehan Disability Scale [SDS] total score) and the indirect effects through changes in NA and Anxiety Cluster scores.

RESULTS

Mean improvements from baseline in NA and Anxiety Cluster scores were significantly greater with LVM-ER versus placebo (both P<0.001), as were the response rates (≥50% score improvement): NA Cluster (44% vs 34%; odds ratio=1.56; P<0.0001); Anxiety Cluster (39% vs 36%; odds ratio=1.19; P=0.041). Mean improvement in SDS total score was also significantly greater with LVM-ER versus placebo (-7.3 vs -5.6; P<0.0001). LVM-ER had an indirect effect on change in SDS total score that was mediated more strongly through NA Cluster score change (86%) than Anxiety Cluster score change (18%); the direct effect was negligible.

LIMITATIONS

NA and Anxiety Cluster scores, developed based on the face validity of individual MADRS and HAMD₁₇ items, were not predefined as efficacy outcomes in any of the studies.

CONCLUSION

In adults with MDD, LVM-ER indirectly improved functional impairment mainly through improvements in NA symptoms and less so via anxiety symptoms.