Clinical utility of desvenlafaxine 50 mg/d for treating MDD: a review of two randomized placebo-controlled trials for the practicing physician

Efficacy and tolerability of desvenlafaxine in the real-world treatment of patients with major depression: a narrative review and an expert opinion paper

INTRODUCTION

Major depressive disorder (MDD) is a common severe mental disorder, requiring a tailored and integrated treatment. Several approaches are available including different classes of antidepressants various psychotherapeutic approaches, and psychosocial interventions. The treatment plan for each patient with MDD should be differentiated on the basis of several clinical, personal, and contextual factors.

AREAS COVERED

Desvenlafaxine - a serotonine-noradrenergic reuptake inhibitor (SNRI) antidepressant - has been approved in the United States in 2008 for the treatment of MDD in adults, and has been recently rediscovered by clinicians due to its good side-effect profile and its clinical effectiveness. A narrative review on efficacy, tolerability and use of desvenlafaxine in clinical practice was carried out. The keywords: 'major depression', 'depression,' 'desvenlafaxine,' 'efficacy,' 'clinical efficacy,' 'side effects', 'tolerability,' 'elderly patients', 'consultation-liaison', 'menopausal', 'young people', 'adolescent' were entered in PubMed, ISI Web of Knowledge, Scopus and Medline. No time limit was fixed, the search strategy was implemented on May 10, 2023.

EXPERT OPINION

Desvenlafaxine should be listed among the optimal treatment strategies for managing people with MDD, whose main strengths are: 1) ease of dosing; 2) favorable safety and tolerability profile, 3) absence of sexual dysfunctions, weight gain and low rate of discontinuation symptoms; 4) low risk of drug-drug interactions.

Species Composition of Anopheles (Diptera: Culicidae) in Selected Forested Tourist Areas of Nigeria Endemic for Malaria

The study was carried out to determine relative abundance, species diversity, of Anopheles species (Diptera: Culicidae) in selected forested areas in Cross River State, Nigeria and the prevalence of malaria infection in the specimens. Mosquitoes were collected using pyrethrum spray catch and Centre for Disease Control light traps modified with yeast and sugar to generate carbon dioxide (CO2) and identified using morphological identification keys. We used a multiplex polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) to simultaneously distinguish sibling species of the An. gambiae s.l, including separation of An. gambiae s.s. and An. coluzzii (Diptera: Culicidae). The samples were also screened for Plasmodium infection using the enzyme-linked immunosorbent assay. One hundred and four Anopheles specimens were collected during the study of which 97% was An. gambiae complex and 3% was An. rufipes (Diptera: Culicidae). Only 77% of the An. gambiae s.l. was identify to species level. The result shows that 41.6% was An. gambiae s.s. and 34.6% was An. coluzzii. No sporozoite of Plasmodium was detected in the Anopheles species. The study also found a hybrid form of An. gambiae s.s. and An. coluzzii. These findings suggest the first documented evidence of hybrid forms of An. gambiae s.s./An. coluzzii in South Eastern Nigeria although its epidemiological implication is still not clear.

New Treatment Options for Depression: A Primer for Internists

Depression continues to be a challenging condition to treat despite the myriad treatment options available. Primary care providers are increasingly tasked with providing second- and third-line treatments for major depressive disorder, and thus, should be familiar with newer medication therapies that are available. In this article, we aim to provide the general internist and other providers who treat depression in their practice with a succinct review of recent developments in the treatment of depression.

A novel prodrug strategy to improve the oral absorption of O-desmethylvenlafaxine

O-Desmethylvenlafaxine (desvenlafaxine, ODV) is the active metabolite of venlafaxine, with similar activity and less risk for pharmacokinetic drug interactions compared to its parent compound venlafaxine. The purpose of this study was to design a series of esters of ODV and assess their potential as ODV prodrugs with improved bioavailability and brain uptake. Seven esters were synthesized and pharmacokinetic screening was performed in rats. The monoester formed on the phenolic hydroxyl of ODV (ODVP-1, ODVP-2, ODVP-3 and ODVP-5) could be degraded to ODV in rat plasma. These four compounds confirmed as possible prodrugs were then studied to evaluated the relative bioavailability of ODV they produced in beagle dogs. ODVP-1, ODVP-2 and ODVP-3 demonstrated higher relative bioavailability of ODV. Finally, ODVP-1, ODVP-2 and ODVP-3 were studied to evaluate their brain uptake in rats. The concentration of ODV in the rat plasma, brain and hypothalamus after administration of ODVP-1, ODVP-2 or ODVP-3 was higher compared with that of ODV. The higher bioavailability, improved pharmacokineics properties and more rapid penetration and translation of ODV suggest that ODVP-1, ODVP-2 or ODVP-3 may warrant further development and application as ODV prodrugs.

Desvenlafaxine in the treatment of major depressive disorder

Desvenlafaxine (DESV) is a newer antidepressant, which inhibits serotonin-norepinephrine reuptake neurotransmission, similarly to venlafaxine, milnacipran and duloxetine. It was approved in February 2008 by the FDA for the treatment of major depressive disorder (MDD), based on well-controlled and adequately powered, large clinical trials demonstrating efficacy and safety for patients with MDD. Currently available data show that DESV has proven efficacy, acceptable safety and tolerability profiles, convenient once-daily dosing and minimal impact on the cytochrome P450 enzyme system in patients with MDD. This mini-review summarizes the clinical data and practical use of DESV under this approved indication.

Symptomatic and functional improvement in employed depressed patients: a double-blind clinical trial of desvenlafaxine versus placebo

OBJECTIVE

This is the first study to assess the efficacy of desvenlafaxine (administered as desvenlafaxine succinate) for improving depressive symptoms and functioning exclusively in employed patients with major depressive disorder (MDD).

METHODS

Gainfully employed (≥20 h/wk) male and female outpatients with MDD were randomly assigned (2:1 ratio) to 12 weeks of double-blind treatment with desvenlafaxine 50 mg/d or placebo. Analysis of covariance was used to compare differences in week 12 adjusted mean changes from baseline on the 17-item Hamilton Depression Rating Scale (HAM-D₁₇) (primary outcome) and Sheehan Disability Scale (SDS) (key secondary outcome) in the intent-to-treat (ITT) population. A predefined, modified ITT population (ie, those in the ITT population with baseline HAM-D₁₇ ≥20) was also analyzed. Tolerability was assessed by recording adverse events and change on the Arizona Sexual Experience Scale.

RESULTS

Baseline HAM-D₁₇ scores for desvenlafaxine (n = 285) and placebo (n = 142) were 22.0 and 21.8, whereas baseline SDS scores were 19.8 and 20.4. Adjusted mean differences between desvenlafaxine and placebo were 2.1 (95% confidence interval [CI], 0.78-3.46; P = 0.002) on the HAM-D₁₇ and 1.3 (95% CI, -0.09 to 2.76; P = 0.067) on the SDS. For the modified ITT sample, desvenlafaxine (n = 208) and placebo (n = 102), baseline HAM-D₁₇ scores were 23.8 and 23.9; the SDS baseline scores were 20.1 and 20.8. Mean differences were 2.6 (95% CI, 0.93-4.22; P = 0.002) on the HAM-D₁₇ and 2.1 (95% CI, 0.36-3.76; P = 0.017) on the SDS. Adverse events and Arizona Sexual Experience Scale scores were comparable between groups.

CONCLUSIONS

Desvenlafaxine 50 mg/d was efficacious for treating MDD in gainfully employed adults. Between-group differences on the SDS narrowly missed statistical significance in the ITT population alone, but the totality of data suggests functional improvements with active treatment.

Genetic polymorphisms of cytochrome P450 enzymes and antidepressant metabolism

INTRODUCTION

The cytochrome P450 (CYP) enzymes are the major enzymes responsible for Phase I reactions in the metabolism of several substances, including antidepressant medications. Thus, it has been hypothesized that variants in the CYP network may influence antidepressant efficacy and safety. Nonetheless, data on this field are still contradictory. The authors aim to give an overview of the published studies analyzing the influence of CYP highly polymorphic loci on antidepressant treatment in order to translate the acquired knowledge to a clinical level.

AREAS COVERED

The authors collected and compared experimental works and reviews published from the 1980s to the present and included in the Medline database. The included studies pertain to the effects of CYP gene polymorphisms on antidepressant pharmacokinetic parameters and clinical outcomes (response and drug-related adverse effects), with a focus on applications in clinical practice. The authors focused mainly on in vivo studies in humans (patients or healthy volunteers).

EXPERT OPINION

Great variability in antidepressant metabolism among individuals has been demonstrated. Thus, with the current interest in individualized medicine, several genetic tests to detect CYP variants have been produced. They provide a potentially useful way to anticipate some clinical outcomes of antidepressant treatment, although they will only be extensively used in clinical practice if precise and specific treatment options and guidelines based on genetic tests can be provided.