Long-term efficacy and safety of modafinil (PROVIGIL((R))) for the treatment of excessive daytime sleepiness associated with narcolepsy

Hits and misses with animal models of narcolepsy and the implications for drug discovery

INTRODUCTION

Narcolepsy is a chronic and rare neurological disorder characterized by disordered sleep. Based on animal models and further research in humans, the dysfunctional orexin system was identified as a contributing factor to the pathophysiology of narcolepsy. Animal models played a larger role in the discovery of some of the pharmacological agents with established benefit/risk profiles.

AREAS COVERED

In this review, the authors examine the phenotypes observed in animal models of narcolepsy and the characteristics of clinically used pharmacological agents in these animal models. Additionally, the authors compare the effects of clinically used pharmacological agents on the phenotypes in animal models with those observed in narcolepsy patients.

EXPERT OPINION

Research in canine and mouse models have linked narcolepsy to the O×R2mutation and orexin deficiency, leading to new diagnostic criteria and a drug development focus. Advancements in pharmacological therapies have significantly improved narcolepsy management, with insights from both clinical experience and from animal models having led to new treatments such as low sodium oxybate and solriamfetol. However, challenges persist in addressing symptoms beyond excessive daytime sleepiness and cataplexy, highlighting the need for further research, including the development of diurnal animal models to enhance understanding and treatment options for narcolepsy.

Investigation of anti-neuronal antibodies and disparity in central hypersomnias

STUDY OBJECTIVES

Microbial antigens can elicit an immune response leading to the production of autoantibodies cross-reacting with autoantigens. Still, their clinical significance in human sera in the context of brain diseases is unclear. Therefore, assessment of natural autoantibodies reacting with their neuropeptides may elucidate the autoimmune etiology of central hypersomnias. The study aims to determine whether serum autoantibody levels differ in patients with different types of central hypersomnias (narcolepsy type 1 and 2, NT1 and NT2; idiopathic hypersomnia, IH) and healthy controls and if the differences could suggest the participation of autoantibodies in disease pathogenesis.

METHODS

Sera from 91 patients with NT1, 27 with NT2, 46 with IH, and 50 healthy controls were examined for autoantibodies against assorted neuropeptides. Participants were screened using questionnaires related to sleep disorders, quality of life, and mental health conditions. In addition, serum biochemical parameters and biomarkers of microbial penetration through the intestinal wall were determined.

RESULTS

A higher prevalence of autoantibodies against neuropeptides was observed only for alpha-melanocytes-stimulating hormone (α-MSH) and neuropeptide glutamic acid-isoleucine (NEI), which differed slightly among diagnoses. Patients with both types of narcolepsy exhibited signs of microbial translocation through the gut barrier. According to the questionnaires, patients diagnosed with NT2 or IH had subjectively worse life quality than patients with NT1. Patients displayed significantly lower levels of bilirubin and creatinine and slightly higher alkaline phosphatase values than healthy controls.

CONCLUSIONS

Overall, serum anti-neuronal antibodies prevalence is rare, suggesting that their participation in the pathophysiology of concerned sleep disorders is insignificant. Moreover, their levels vary slightly between diagnoses indicating no major diagnostic significance.

Pitolisant-supported bridging during drug holidays to deal with tolerance to modafinil in patients with narcolepsy

STUDY OBJECTIVES

Modafinil is a common treatment for excessive daytime sleepiness (EDS) in narcolepsy. The long-term use of modafinil can lead to tolerance with the loss of efficacy and the continuous increase of its dose. Pharmacological strategies to deal with the tolerance to modafinil are lacking. We investigated the efficacy and safety of pitolisant-supported bridging during drug holidays in patients with tolerance to modafinil.

METHODS

Narcolepsy patients on monotherapy with modafinil who developed symptoms of tolerance were eligible. The following alternating therapy regimen was established: Monday to Friday patients continued on modafinil whereas Saturday and Sunday they switched to pitolisant to "bridge" the EDS symptoms. Patients were assessed at baseline and after three months with the Epworth Sleepiness Scale (ESS) and the Ullanlinna Narcolepsy Scale (UNS). Health-related quality of life (HrQol) was evaluated by EuroQol5D. Adverse events were documented in the patients' diaries.

RESULTS

41 patients aged 30.9 ± 5.6 years were included. After three months of the alternating therapy regimen, the symptoms of tolerance decreased and the modafinil dose could be reduced by 41% (p < 0.01) resulting in better safety. The EDS improved on ESS (baseline: 18.2 ± 4.2, follow-up: 12.6 ± 4.0, p < 0.0001) and UNS (baseline: 25.8 ± 7.9, follow-up: 18.9 ± 5.9, p < 0.0001). The HrQol increased significantly.

CONCLUSION

Patients with tolerance to modafinil could benefit from pitolisant-supported bridging during drug holidays. This alternating pharmacological strategy proved to be safe and helped to reduce EDS and to decrease the modafinil dose. Further randomized controlled studies are required to evaluate the different strategies to deal with the tolerance to modafinil.

CLINICAL TRIAL REGISTRATION NUMBER

Clinical Trials.gov Identifier NCT05321355.

The Role of Sodium Oxybate in Idiopathic Hypersomnia: A Case Report Showing Improvement of Excessive Daytime Sleepiness and Reduced Symptoms

Our aim is to report the clinical profile and outcome of patients diagnosed with idiopathic hypersomnia (IH). Idiopathic hypersomnolence is a complex, debilitating, and uncommon sleep disorder manifested mainly by chronic excessive daytime sleepiness (EDS). This paper reports on the treatment of a patient with idiopathic hypersomnia who was treated with low sodium oxybate (LXB) due to a lack of response to the first-line drug modafinil. This patient, who presented with worsening excessive daytime sleepiness, sleep drunkenness, and sleep disturbances, was diagnosed with idiopathic hypersomnia by overnight polysomnography (PSG) and a multiple sleep latency test (MSLT). Stimulant agent modafinil was prescribed along with sleep hygiene education. Her symptoms did not respond to modafinil, and she was switched to a recently approved newer medication, i.e., low sodium oxybate.

Quality of life changes and their predictors in young adult narcolepsy patients after treatment: A real-world cohort study

Background

We conducted a five-year prospective follow-up study to track the real-world quality of life of patients with narcolepsy after medication and analyzed predictors.

Methods

The study ultimately included 157 participants who completed 5-year follow-up, 111 had type 1 narcolepsy (NT1) and 46 had type 2 narcolepsy (NT2). Polysomnography, multiple sleep latency test, actigraphy and HLA-typing were conducted. The Short Form 36 Health Survey Questionnaire (SF-36), the Stanford Center for Narcolepsy Sleep Inventory, the Epworth Sleepiness Scale (ESS), the visual analog for hypersomnolence (VAS), and Conners' Continuous Performance Test were used. Descriptive statistics, repeated measures, and hierarchical linear models were applied for analysis.

Results

Most demographic and clinical data did not significantly differ between groups, but the NT1 group had significantly more overweight, more severe narcoleptic symptoms, more positive HLA typing, shorter mean sleep latency, and more sleep onset rapid eye movement periods. No significant change to the physical domains of SF-36 was found in the total group, but we observed significant changes in emotional role functioning and social function. The NT1 group showed significant improvements in physical role functioning, emotional role functioning, and social function. The NT2 group demonstrated significant improvements in emotional role functioning. At the baseline, the NT2 group had significantly better scores, but there was no significant group difference after treatment, except for physical and social function. ESS and VAS were significantly improved during follow-up. At the baseline, the NT1 group had significantly higher ESS and VAS scores, and continuously significantly higher ESS scores during follow-up. Narcolepsy types, HLA typing, age of onset, symptom severity, attention and vigilance were significantly correlated with SF-36.

Conclusion

Symptom control greatly associates with the quality of life in narcoleptic patients, and medication can play the most important role. Management targeting narcoleptic symptoms, attention impairment, and drug adherence should be provided.

Instant energy stimulant nutraceutical cube formulation

The need for innovative study and formulation is praised from the claim of those occupational personnel including software Engineers, those who get tremendously tired after their office work 9:00am -05:00pm. That time tea/coffee/health drinks won’t work with many pros and cons because it takes a long time to prepare and to initiate action, sometimes addiction, its lengthy preparation and blending processes and single mild stimulation drug efficiency. The method development and preparation of a formulation processing the cumulative effects of CNS stimulant, effective natural vasodilatation, energy boosting to brain, normalize function of immune system to reduce tiredness and fatigue, as brain tonic with caffeine dust, Theobroma Cacao dust, glucose/sucrose, vitamin –C, Brahmi’s leaf extract respectively. These components were in the form of solid cubes formulation with dispersible deliquescent additives of sodium citrate. Thus, get soluble in a low temperature 60-70°C of Luke warm liquid medium for drinks. These low temperature instant-energy boosters take less time to prepare and avoid thermo-labile constituent’s degradation. This formulation acts as multifactor benefits to the volunteers as instant stimulation and steady energy–brain tonic along with zero recurrent hangovers.

Pharmacologic Therapy for Narcolepsy

Narcolepsy is a lifelong disorder that adversely affects daytime function and quality of life. Major symptoms include excessive daytime sleepiness with irrepressible sleep attacks and cataplexy. Recent developments in the understanding of the pathobiology of narcolepsy, as well as the neuronal systems involved in the regulation of wakefulness have led to development of new pharmacologic approaches to therapy. In this paper, we review available pharmacologic treatments for narcolepsy as well as agents currently under investigation.

Long-term effects of solriamfetol on quality of life and work productivity in participants with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea

STUDY OBJECTIVES

Solriamfetol, a dopamine/norepinephrine reuptake inhibitor, is approved in the United States and European Union for excessive daytime sleepiness in adults with narcolepsy (75-150 mg/day) or obstructive sleep apnea (OSA; 37.5-150 mg/day). In 12-week studies, solriamfetol was associated with improvements in quality of life in participants with narcolepsy or OSA. These analyses evaluated the long-term effects of solriamfetol on quality of life.

METHODS

Participants with narcolepsy or OSA who completed previous solriamfetol studies were eligible. A 2-week titration was followed by a maintenance phase ≤ 50 weeks (stable doses: 75, 150, or 300 mg/day). Quality of life assessments included Functional Outcomes of Sleep Questionnaire short version, Work Productivity and Activity Impairment Questionnaire: Specific Health Problem, and 36-Item Short Form Health Survey version 2. Mean (standard deviation) changes from baseline to end of study were evaluated. Data were summarized descriptively. Adverse events were assessed.

RESULTS

Safety population comprised 643 participants (417 OSA, 226 narcolepsy). Solriamfetol improved Functional Outcomes of Sleep Questionnaire short version Total scores (mean change [standard deviation], 3.7 [3.0]) and 36-Item Short Form Health Survey version 2 Physical and Mental Component Summary scores (3.1 [6.9] and 4.3 [8.4], respectively); improvements were sustained throughout treatment. On Work Productivity and Activity Impairment Questionnaire: Specific Health Problem, solriamfetol reduced (improved) % presenteeism, % overall work impairment, and % activity impairment by a minimum of 25%. Common adverse events (≥ 5%): headache, nausea, nasopharyngitis, insomnia, dry mouth, anxiety, decreased appetite, and upper respiratory tract infection.

CONCLUSIONS

Long-term solriamfetol treatment was associated with clinically meaningful, sustained improvements in functional status, work productivity, and quality of life for up to 52 weeks. Adverse events were similar between narcolepsy and OSA.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: A Long-Term Safety Study of JZP-110 in the Treatment of Excessive Sleepiness in Subjects with Narcolepsy or OSA; Identifier: NCT02348632; URL: https://clinicaltrials.gov/ct2/show/NCT02348632.

CITATION

Weaver TE, Pepin J-L, Schwab R, et al. Long-term effects of solriamfetol on quality of life and work productivity in participants with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea. J Clin Sleep Med. 2021;17(10):1995-2007.

Treatment of central disorders of hypersomnolence: an American Academy of Sleep Medicine systematic review, meta-analysis, and GRADE assessment

INTRODUCTION

This systematic review provides supporting evidence for the accompanying clinical practice guideline on the treatment of central disorders of hypersomnolence in adults and children. The review focuses on prescription medications with U.S. Food & Drug Administration approval and nonpharmacologic interventions studied for the treatment of symptoms caused by central disorders of hypersomnolence.

METHODS

The American Academy of Sleep Medicine commissioned a task force of experts in sleep medicine to perform a systematic review. Randomized controlled trials and observational studies addressing pharmacological and nonpharmacological interventions for central disorders of hypersomnolence were identified. Statistical analyses were performed to determine the clinical significance of all outcomes. Finally, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) process was used to assess the evidence for the purpose of making specific treatment recommendations.

RESULTS

The literature search identified 678 studies; 144 met the inclusion criteria and 108 provided data suitable for statistical analyses. Evidence for the following interventions is presented: armodafinil, clarithromycin, clomipramine, dextroamphetamine, flumazenil, intravenous immune globulin (IVIG), light therapy, lithium, l-carnitine, liraglutide, methylphenidate, methylprednisolone, modafinil, naps, pitolisant, selegiline, sodium oxybate, solriamfetol, and triazolam. The task force provided a detailed summary of the evidence along with the quality of evidence, the balance of benefits and harms, patient values and preferences, and resource use considerations.

CITATION

Maski K, Trotti LM, Kotagal S, et al. Treatment of central disorders of hypersomnolence: an American Academy of Sleep Medicine systematic review, meta-analysis, and GRADE assessment. J Clin Sleep Med. 2021;17(9):1895-1945.

Health-related quality of life in narcolepsy: A systematic review and meta-analysis

To date, there has been no systematic analysis of the literature regarding health-related quality of life in narcolepsy. This systematic review aimed to examine the impact of narcolepsy on health-related quality of life, measured through standardised health-related quality of life questionnaires such as the Short Form 36 and Functional Outcome of Sleep Questionnaire. The following databases: Medline, Embase, Cinahl, and Web of Science were searched for studies that investigated health-related quality of life in adults with narcolepsy. Studies were reviewed independently by two reviewers, and a random-effects meta-analysis was performed. A total of 30 studies were eligible for inclusion in the review. Additionally, meta-analyses were conducted for the Short Form 36 and the EQ5D. The Short Form 36 meta-analysis identified that the pooled mean scores for the Physical Component Summary (45.91) were less affected than the Mental Component Summary (42.98). People with narcolepsy experience substantially lower health-related quality of life when compared with the general population norms of the USA, UK, France and Norway, as well as compared with people with chronic diseases such as multiple sclerosis, diabetes, hypertension and epilepsy. Further research is warranted to identify the longitudinal effects of narcolepsy on health-related quality of life, and to develop a narcolepsy-specific health-related quality of life tool.

Chronic modafinil administration to preadolescent rats impairs social play behavior and dopaminergic system

Some clinical trials are investigating modafinil (Mod) as a treatment for attentional deficit and hyperactivity disorder (ADHD) in children and adolescents. Mod increases dopamine (DA) levels in the reward system by blocking dopamine transporter (DAT). Social interactions are rewarding behaviors and evidence reveals the importance of reward circuitry in social interactions. Chronic psychostimulant treatments alter DA neurotransmission and associated behaviors. The aim of this work was to evaluate the effects of chronic Mod treatment during preadolescence on social play behavior, locomotor activity, and DA in nucleus accumbens (NAc). Preadolescent male Sprague-Dawley rats were injected with Mod (75 mg/kg i.p.) or vehicle for 14 days (PND22 to PND35). After that, we measured social play behavior, content and DA release in NAc by HPLC coupled to electrochemical detection, protein levels of DA type 2 receptor (D₂) by Western blot and DA kinetic by fast-scan cyclic voltammetry (FSCV) in NAc. Regarding social play, the total number of pinning events decreased in the Mod group compared with the vehicle. The K⁺-stimulated DA release in NAc was significantly lower in Mod-treated rats compared with vehicle group. Also, Mod increases locomotor activity at the first injection, but this effect is almost completely lost at day 14 of Mod treatment. Chronic Mod treatment during preadolescence in rats impairs dopaminergic neurotransmission in NAc and decreases the capacity of rats to perceive rewarding effects of social play. Importantly, as Mod is being evaluated to treat ADHD in children and adolescents, potential effects on social behavior should be considered since this kind of behavior in this particular stage is crucial for neurodevelopment.

Long-term use of pitolisant to treat patients with narcolepsy: Harmony III Study

Study Objectives

To asses the long-term safety and efficacy of pitolisant, an histamine H3-receptor antagonist, on narcolepsy.

Methods

This open-label, single-arm, pragmatic study, recruited adult patients with narcolepsy and Epworth Sleepiness Scale (ESS) score ≥12. After a titration period, patients were treated for up to 1 year with oral pitolisant once-a-day at up to 40 mg. Concomitant stimulants and anti-cataplectic agents were allowed. The primary endpoint was safety; secondary endpoints included ESS, cataplexy, and other diary parameters.

Results

Patients (n = 102, 75 with cataplexy) received pitolisant, for the first time in 73 of them. Sixty-eight patients (51 with cataplexy) completed the 12-month treatment. Common treatment-emergent adverse events were headache (11.8% of patients), insomnia (8.8%), weight gain (7.8%), anxiety (6.9%), depressive symptoms (4.9%), and nausea (4.9%). Seven patients had a serious adverse effect, unrelated to pitolisant except for a possibly related miscarriage. One-third of patients stopped pitolisant, mostly (19.6%) for insufficient benefit. ESS score decreased by 4.6 ± 0.6. Two-thirds of patients completing the treatment were responders (ESS ≤ 10 or ESS decrease ≥ 3), and one third had normalized ESS (≤10). Complete and partial cataplexy, hallucinations, sleep paralysis, and sleep attacks were reduced by 76%, 65%, 54%, 63%, and 27%, respectively. Pitolisant as monotherapy (43% of patients) was better tolerated and more efficacious on ESS than on add-on, but efficacy was maintained in this last case.

Conclusions

Long-term safety and efficacy of pitolisant on daytime sleepiness, cataplexy, hallucinations, and sleep paralysis is confirmed.

A review on modafinil: the characteristics, function, and use in critical care

In critically ill patients, sleep is generally interrupted. Some factors that lead to such sleep interruption include the intensive care unit (ICU) circumstance, primary medical disease itself, mental stress, and impacts of many drugs and other managements utilized to treat ICU patients. Another illness that may cause profound daytime somnolence is narcolepsy. Modafinil, methylphenidate and amphetamines are used as stimulants to treat symptoms, such as extreme daytime sleepiness, cataplexy and nocturnal sleep disruption. Such stimulants can increase awareness, improve perception and thinking, as well as assist in keeping people awake. The exact mechanism of action of modafinil is unclear. In vitro studies have demonstrated that binding of modafinil to the dopamine reuptake pump can prevent the reuptake of dopamine, resulting in a boost in extracellular dopamine. Modafinil is a racemic compound containing l and d isomers. Peak plasma concentrations of the drug occur at 2–4 h after administration; therefore, the absorption of modafinil is considered fast. Modafinil is properly distributed in tissues by binding to plasma proteins moderately. Despite the likely role of modafinil in improving cognition and arousal in critically ill patients, the available data on the use of modafinil in the ICU setting is limited. The aim of the study was to review the novel usage of modafinil for alleviation of fatigue, excessive daytime somnolence (EDS), and/or depression in critically ill patients.

The Risk of Hospitalization for Motor Vehicle Accident Injury in Narcolepsy and the Benefits of Stimulant Use: A Nationwide Cohort Study in Taiwan

STUDY OBJECTIVES

To examine the risk of hospitalization for motor vehicle accident injury (MVAI) in patients with narcolepsy and the effects of stimulant use on MVAI occurrence in patients with narcolepsy.

METHODS

This is a population-based, retrospective cohort study using Taiwan's National Health Insurance Research Database between 2000 and 2013. We included patients with narcolepsy based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes, 347. The case and matched control participants were selected in a ratio of 1:3, and the traffic accident (ICD-9-CM codes: E810-E819) plus injury codes (ICD-9-CM codes: 800.xx-999.xx) due to MVAI following hospitalization were used for the study outcome. The type of injury, causes, intentionality, and the effects of stimulant use on patients with narcolepsy were also assessed.

RESULTS

A total of 1,316 participants were enrolled, including 329 participants with narcolepsy and 987 participants without narcolepsy. During a 14-year follow-up period, a total of 104 participants had MVAI, of whom 47 (1,559.54 per 100,000 person-years) belonged to the narcolepsy cohort and 57 (556.21 per 100,000 person-years) to the non-narcolepsy cohort. After adjusting for covariates, the risk of hospitalization for MVAI among participants with narcolepsy was still significantly higher than those without narcolepsy (adjusted hazard ratio = 6.725; 95% confidence interval = 4.421-10.231; P < .001). The use of modafinil or methylphenidate, as monotherapy or combined treatment, was associated with a lower risk of MVAI in the narcolepsy cohort.

CONCLUSIONS

Patients with narcolepsy may have a higher risk of hospitalization for MVAI and stimulant use could mitigate such risk.

Management Of Excessive Sleepiness In Patients With Narcolepsy And OSA: Current Challenges And Future Prospects

Excessive daytime sleepiness (EDS) can be caused by insufficient sleep but is also a manifestation of medical or sleep disorders and a side effect of medications. It impacts quality of life and creates safety concerns in the home, at work, and on the roads. Screening questionnaires can be used to estimate EDS, but further evaluation is necessary. EDS is a common symptom of both narcolepsy and obstructive sleep apnea (OSA). Polysomnography and multiple sleep latency testing are used to diagnose these disorders. However, isolating the primary etiology of EDS can be challenging and may be multifactorial. Untreated OSA can show polysomnographic findings that are similar to narcolepsy. The effects of sleep deprivation and certain medications can also affect the polysomnographic results. These challenges can lead to misdiagnosis. In addition, narcolepsy and OSA can occur as comorbid disorders. If EDS persists despite adequate treatment for either disorder, a comorbid diagnosis should be sought. Thus, despite advances in clinical practice, appropriate management of these patients can be challenging. This review is focused on EDS due to OSA and narcolepsy and addresses some of the challenges with managing this patient population.

The mutagenic effect of psychostimulant modafinil in Wistar rats in vivo

The demands imposed by today's world require a fast and efficient society, then, significant section of the population looks for support from psychotropic medicine. Modafinil is a psychostimulant that promotes wakefulness, it being recommended for treatment of narcolepsy, obstructive sleep apnea, and shift-work sleep disorder, besides being a cognitive function potentiator. However, chemical components of drugs can alter genetic material. Thus, the present study evaluated the cytotoxic and clastogenic/mutagenic potential of 0.25, 0.50, and 0.75 mg of Modafinil/mL of corn oil/100g body weight in acute treatments and subacute treatments, 15 days, to Rattus norvegicus, treated via gavage in a single daily dose. The drug was not cytotoxic at any of the evaluated doses in either of the treatments. However, the medicine showed clastogenic/mutagenic activity in the acute treatment group at the standard dose and at double dose. Data from the present study indicates that there should be greater caution as to the use of this psychostimulant by human beings.

Modafinil: its discovery, the early European and North American experience in the treatment of narcolepsy and idiopathic hypersomnia, and its subsequent use in other medical conditions

Adrafinil, a new molecule identified by a French drug company, L. Lafon Ltd, in 1974, was found to cause a significant dose-dependent increase in motor activity in mice, without exerting peripheral sympathomimetic effects. As early as 1977-78, Michel Jouvet prescribed adrafinil to narcoleptic patients, but without consistent results. Meanwhile the kinetics of adrafinil led to the identification of an active metabolite, modafinil. In 1983, Jouvet and Bastuji prescribed modafinil to narcoleptic and idiopathic hypersomnia patients and obtained a significant decrease of excessive daytime sleepiness and sleep attacks in a majority of patients. L. Lafon Ltd was initially not interested in developing this molecule for market however, thanks to Jouvet's insistance, it decided to start clinical trials in both healthy volunteers and narcoleptic patients as well as conduct animal studies. Results were excellent and led to the use of modafinil by the French army during the Gulf War in January-February 1991, as well as to the official registration of the drug in France in 1992. Subsequent multicenter controlled clinical trials in North America confirmed the findings in Europe. Modafinil was later used to treat sleepiness, somnolence and fatigue in a large number of medical conditions.

An Overview of the Clinical Uses, Pharmacology, and Safety of Modafinil

Modafinil (MOD) is a wakefulness-inducing compound prescribed for treatment of excessive daytime sleepiness as a consequence of sleep disturbances such as shift work sleep disorder, obstructive sleep apnea, restless leg syndrome, or narcolepsy. While providing effective results in patients with sleepiness, MOD also produces positive outcomes in the management of fatigue associated with different conditions including depression, cancer, or tiredness in military personnel. Although there is clear evidence of the stimulant effects of MOD, current data also show that administration of this drug apparently induces positive neurobiological effects, such as improvement in memory. However, serious concerns have been raised since some reports have suggested MOD dependence. Taken together, these findings highlight the need to characterize the changes induced by MOD which have been observed in several neurobiological functions. Moreover, further work should follow up on the likely long-term effects of this drug if used for treatment of drowsiness and tiredness. Here, we review and summarize recent findings of the medical uses of MOD in the management of sleepiness and fatigue associated with depression or cancer as well as exhaustion in military personnel. We also discuss the available literature related with the cognitive enhancing properties of this stimulant, as well as what is known and unknown about MOD addiction.

Effectiveness and side-effect profile of stimulant therapy as monotherapy and in combination in the central hypersomnias in clinical practice

Effectiveness and side-effect profile data on pharmacotherapy for daytime sleepiness in central hypersomnias are based largely upon randomized controlled trials. Evidence regarding the use of combination therapy is scant. The aim of this study was to examine the effectiveness and occurrence of drug-related side effects of these drugs in routine clinical practice. Adult patients diagnosed with a central hypersomnia during a 54-month period at a tertiary sleep disorders centre were identified retrospectively. Side effects were recorded at every follow-up visit. A total of 126 patients, with 3275 patient-months of drug exposure, were categorized into narcolepsy type 1 (n = 70), narcolepsy type 2 (n = 47) and idiopathic hypersomnia (n = 9). Modafinil was the most common drug used as a first-line treatment (93%) and in combination therapy (70%). Thirty-nine per cent of the patients demonstrated a complete, 25% partial and 36% a poor response to treatment. Combination treatment improved daytime sleepiness in 55% of the patients with residual symptoms despite monotherapy. Sixty per cent of patients reported side effects, and 30% reported treatment-limiting side effects. Drugs had similar side-effect incidence (P = 0.363) and their side-effect profile met those reported in the literature. Twenty-seven per cent of the patients received combination treatment and had fewer side effects compared to monotherapy (29.4% versus 60%, respectively, P = 0.001). Monotherapy appears to achieve satisfactory symptom control in most patients with central hypersomnia, but significant side effects are common. Combination therapy appears to be a useful and safe option in patients with refractory symptoms.

Synthesis of (R)-Modafinil via Organocatalyzed and Non-Heme Iron-Catalyzed Sulfoxidation Using H2O2 as an Environmentally Benign Oxidant

The first organocatalyzed sulfoxidation reaction towards enantioenriched (R)-modafinil (Armodafinil®), a drug against narcolepsy, is reported here. A series of chiral organocatalysts, e.g., different chiral BINOL-phosphates, or a fructose-derived N-substituted oxazolidinone ketone (Shi catalyst) were applied for the sulfoxidation reaction with environmentally friendly H2O2 as a convenient oxygen transferring agent. Furthermore, the potential of a biomimetic catalytic system consisting of FeCl3 and a dipeptide-based chiral ligand was demonstrated, which constitutes the most successful asymmetric non-heme iron-catalyzed synthesis of (R)-modafinil so far.

Narcolepsy

Narcolepsy is a chronic sleep disorder that has a typical onset in adolescence and is characterized by excessive daytime sleepiness, which can have severe consequences for the patient. Problems faced by patients with narcolepsy include social stigma associated with this disease, difficulties in obtaining an education and keeping a job, a reduced quality of life and socioeconomic consequences. Two subtypes of narcolepsy have been described (narcolepsy type 1 and narcolepsy type 2), both of which have similar clinical profiles, except for the presence of cataplexy, which occurs only in patients with narcolepsy type 1. The pathogenesis of narcolepsy type 1 is hypothesized to be the autoimmune destruction of the hypocretin-producing neurons in the hypothalamus; this hypothesis is supported by immune-related genetic and environmental factors associated with the disease. However, direct evidence in support of the autoimmune hypothesis is currently unavailable. Diagnosis of narcolepsy encompasses clinical, electrophysiological and biological evaluations, but simpler and faster procedures are needed. Several medications are available for the symptomatic treatment of narcolepsy, all of which have quite good efficacy and safety profiles. However, to date, no treatment hinders or slows disease development. Improved diagnostic tools and increased understanding of the pathogenesis of narcolepsy type 1 are needed and might lead to therapeutic or even preventative interventions.

Diagnosis and management of narcolepsy in the Indian scenario

INTRODUCTION

The diagnosis and management of narcolepsy in the Indian context needs to be revisited especially in the wake of concerns raised by sleep medicine experts that the entity could be formidably underdiagnosed, as well as undertreated in our setting.

MATERIALS AND METHODS

The history, clinical records, polysomnographic/multiple sleep latency test data, and treatment records of five hundred consecutive patients attending a dedicated sleep clinic between the years 2013 and 2016 were retrospectively analyzed. The response to treatment measures and improvement in daytime functioning were periodically assessed by personal/telephonic interview and E-mail communication.

RESULTS

Thirteen patients were diagnosed with narcolepsy based on the standard criteria of which three had cataplexy. The mean age of presentation was 23.23 years and the male:female ratio was 2.25:1. The mean duration from the onset of symptoms to diagnosis was 4.2 years. Two patients responded to nonpharmacological interventions alone, and six to modafinil, while two patients remained symptomatic and required treatment with methylphenidate. One patient was lost to follow-up, while two others are due for their first follow-up.

CONCLUSION

A refurbished outlook of the diagnostic methodology and treatment paths tailored to our clinical scenario can potentially impact the future of narcolepsy management and research in our country.

Modafinil Therapy for Apathy in an Elderly Patient

Objective:

To present a case of successful treatment of apathy syndrome with modafinil.

Case Summary:

A 78-year-old man with dementia and depression was also experiencing apathy that did not respond to antidepressants including escitalopram, a selective serotonin-reuptake inhibitor (SSRI). Escitalopram was discontinued and modafinil, a novel vigilance-promoting agent pharmacologically distinct from stimulants, was used to successfully treat the apathy. The dosage regimen was initiated at 50 mg and titrated to 200 mg/day over 4 weeks. Apathy was assessed using the Apathy Evaluation Scale developed specifically to identify apathy and also to differentiate this from depression.

Discussion:

Apathy, a common behavioral problem, is often mistaken for depression; however, apathy differs from depression in symptomatology, clinical presentation, and treatment options. SSRIs, a common treatment for depression, are known to cause or increase apathy. Deficits in the dopamine receptor system are involved in the etiology of apathy; modafinil's increased dopaminergic transmission is thought to help alleviate apathy. Due to its relative lack of drug interactions, modafinil is a good alternative for elderly patients, who often receive multiple medications. Apathy improved significantly after treatment with modafinil in this patient. To the best of our knowledge, as of January 22, 2007, this is the first report of modafinil treatment of apathy syndrome.

Conclusions:

Modafinil may be useful in treating apathy syndrome. Its role in the treatment of apathy requires further testing in clinical trials.

Correlating behaviour and gene expression endpoints in the dopaminergic system after modafinil administration in mouse

The mechanisms of action of modafinil continue to be poorly characterised and its potential for abuse in preclinical models remains controverted. The aim of this study was to further elucidate the mechanism of action of modafinil, through a potential behavioural and molecular association in the mouse. A conditioned place preference (CPP) paradigm was implemented to investigate the rewarding properties of modafinil. Whole genome expression and qRT-PCR analysis were performed on the ventral tegmental area (VTA), nucleus accumbens (NAC) and prefrontal cortex (PFC) of modafinil-treated and control animals. Modafinil administration (65 mg/kg) induced an increase in locomotor activity, an increase in the change of preference for the drug paired side after a conditioning period as well as changes to gene expression profiles in the VTA (120 genes), NAC (23 genes) and PFC (19 genes). A molecular signature consisting of twelve up-regulated genes was identified as common to the three brain regions. Multiple linear correlation analysis showed a strong correlation (R(2)>0.70) between the behavioural and molecular endpoints in the three brain regions. We show that modafinil had a concomitant effect on CPP, locomotor activity, and up-regulation of interferon-γ (IFN-γ) regulated genes (Gbp2, Gbp3, Gbp10, Cd274, Igtp), while correlating the latter set of genes with behaviour changes evaluated through the CPP. A potential association can be proposed based on the dysregulation of p47 family genes and Gbp family of IFN-γ induced GTPases. In conclusion, these findings suggest a link between the behavioural and molecular events in the context of modafinil administration.

Structured cues or modafinil for fatigue amelioration in clinicians? A double-blind, randomized controlled trial of critical clinical information recall in fatigued clinicians

OBJECTIVES

To evaluate the impact of modafinil on "free" and "cued" recall of clinical information in fatigued but nonsleep-deprived clinicians.

SUMMARY BACKGROUND DATA

Despite attempts to minimize sleep deprivation through redesign of the roster of residents and staff surgeons, evidence suggests that fatigue remains prevalent. The wake-promoting agent modafinil improves cognition in the sleep-deprived fatigued state and may improve information recall in fatigued nonsleep-deprived clinicians.

METHODS

Twenty-four medical undergraduates participated in a double-blind, parallel, randomized controlled trial (modafinil-200 mg:placebo). Medication was allocated 2 hours before a 90-minute fatigue-inducing, continuous performance task (dual 2-back task). A case history memorization task was then performed. Clinical information recall was assessed as "free"(no cognitive aids) and "cued"(using aid memoirs). Open and closed cues represent information of increasing specificity to aid the recall of clinical information. Fatigue was measured objectively using the psychomotor vigilance task at induction, before and after the dual 2-back task.

RESULTS

Modafinil decreased false starts and lapses (modafinil = 0.50, placebo = 9.83, P < .05) and improved psychomotor vigilance task performance (Decreased Performance, modafinil = 0.006, placebo = 0.098, P < .05). Modafinil improved free information recall (modafinil = 137.8, placebo = 106.0, P < .01). There was no significant difference between groups in the amount of information recalled with open (modafinil = 62.3, placebo = 52.8, P = .1) and closed cues (modafinil = 80.1, placebo = 75.9, P = .3).

CONCLUSION

Modafinil attenuated fatigue and improved free recall of clinical information without improving cue-based recall under the design of our experimental conditions. Memory cues to aid retrieval of clinical information are convenient interventions that could decrease fatigue-related error without adverse effects of the neuropharmacology.

Quality measures for the care of patients with narcolepsy

ABSTRACT

The American Academy of Sleep Medicine (AASM) commissioned a Workgroup to develop quality measures for the care of patients with narcolepsy. Following a comprehensive literature search, 306 publications were found addressing quality care or measures. Strength of association was graded between proposed process measures and desired outcomes. Following the AASM process for quality measure development, we identified three outcomes (including one outcome measure) and seven process measures. The first desired outcome was to reduce excessive daytime sleepiness by employing two process measures: quantifying sleepiness and initiating treatment. The second outcome was to improve the accuracy of diagnosis by employing the two process measures: completing both a comprehensive sleep history and an objective sleep assessment. The third outcome was to reduce adverse events through three steps: ensuring treatment follow-up, documenting medical comorbidities, and documenting safety measures counseling. All narcolepsy measures described in this report were developed by the Narcolepsy Quality Measures Work-group and approved by the AASM Quality Measures Task Force and the AASM Board of Directors. The AASM recommends the use of these measures as part of quality improvement programs that will enhance the ability to improve care for patients with narcolepsy.

High resolution mapping of modafinil induced changes in glutamate level in rat brain

Modafinil is marketed in the United States for the treatment of narcolepsy and daytime somnolence due to shift-work or sleep apnea. Investigations of this drug in the treatment of cocaine and nicotine dependence in addition to disorders of executive function are also underway. Modafinil has been known to increase glutamate levels in rat brain models. Proton magnetic resonance spectroscopy (1HMRS) has been commonly used to detect the glutamate (Glu) changes in vivo. In this study, we used a recently described glutamate chemical exchange saturation transfer (GluCEST) imaging technique to measure Modafinil induced regional Glu changes in rat brain and compared the results with Glu concentration measured by single voxel 1HMRS. No increases in either GluCEST maps or 1HMRS were observed after Modafinil injection over a period of 5 hours. However, a significant increase in GluCEST (19 ± 4.4%) was observed 24 hours post Modafinil administration, which is consistent with results from previous biochemical studies. This change was not consistently seen with 1HMRS. GluCEST mapping allows regional cerebral Glu changes to be measured and may provide a useful clinical biomarker of Modafinil effects for the management of patients with sleep disorders and addiction.

Synthesis and psychobiological evaluation of modafinil analogs in mice

Background and the purpose of the study

Modafinil, a novel wake-promoting agent with low potential for abuse and dependence, has a reliable structure to find some novel derivatives with better activity and lower potential for abuse and risk of dependency. This study was designed to evaluate psychobiological activity of some novel N-aryl modafinil derivatives.

Methods

Seven novel N-aryl modafinil derivatives were synthesized through three reactions: a) preparation of benzhydrylsulfanyl acetic acid through reaction of benzhydrol with thioglycolic acid, b) formation of desired amide by adding the substituted aniline to activated acid with EDC (1-ethyl-3-(3-dimethyl amino propyl) carbodiimide). This reaction was catalyzed by HOBt (N- hydroxylbenzotriazole), and c) oxidation of sulfur to sulfoxide group with H₂O₂. Then, their psychobiological effect on the performance of male albino mice were compared to that of modafinil as following: wakefulness by determining the effects of derivatives on phenobarbital-induced loss of the righting reflex (LOPR); exploratory activity by measuring activity in the open field test (OFT); depression by measuring immobility time (IT) during forced swimming test (FST) and the anxiogenic and anxiolytic like effects by using elevated plus-maze test (EPM). All tests were videotaped and analyzed for the frequency and duration of the behaviors during the procedures.

Conclusions

2-(Benzhydrylsulfonyl)-N-(4-chlorophenyl)acetamide (4c) showed comparable result in LOPR test. However, all analogs were found to be stimulant except 2-(benzhydrylsulfinyl)-N-phenylacetamide (4a). Also 4c led the most exploratory activity in mice among derivatives. FST results showed that 4a had the longest IT while modafinil, 2-(benzhydrylsulfinyl)-N-(3-chlorophenyl) acetamide (4b) and 2-(benzhydrylsulfinyl)-N-(4-ethylphenyl) acetamide (4d) had the shortest IT. In EPM, all derivatives showed anxiogenic-like behavior since they decreased open arms time and open arms entries and simultaneously increased close arms time.

Population pharmacokinetics of modafinil and its acid and sulfone metabolites in Chinese males

BACKGROUND

Modafinil is a psychostimulant used to treat excessive sleepiness. The aim of this study was to develop a population pharmacokinetic model of modafinil and its major metabolites in Chinese male adults and to identify covariates that predict variability in disposition.

METHODS

Eighty healthy volunteer subjects were randomized to 4 oral dose groups: 3 doses of 50 mg of modafinil, 3 doses of 100 mg of modafinil, 2 doses of 200 mg of modafinil plus 1 dose of placebo, or 3 doses of placebo (each dose given 8 hourly). Blood samples were collected up to 58 hours post-first dose for plasma concentrations of modafinil and its metabolites. Pharmacokinetic data analyses were performed using noncompartmental and compartmental approaches. The population pharmacokinetic study was conducted using the nonlinear mixed-effects model software, NONMEM, and validated using the bootstrap, crossvalidation and visual predictive check approaches.

RESULTS

Data were best described by a 5-compartment model: 2 compartments for modafinil (first-order absorption from gut compartment) and 1 each for modafinil acid and modafinil sulfone. A covariate analysis identified body weight as influencing volumes of the central and peripheral compartments for modafinil. All the parameters were estimated with good precision (relative standard error < 39%). The visual predictive check found that the final pharmacokinetic model adequately predicted observed concentrations of all 3 molecular species. The authors developed dosing schedules to achieve minimum trough plasma modafinil concentrations of 3 mcg/mL.

CONCLUSIONS

A robust population pharmacokinetic model for modafinil and its metabolites was developed for the first time. Based on this model, individualized dosing based on weight is now possible.

Narcolepsy: a review

Narcolepsy is a lifelong sleep disorder characterized by a classic tetrad of excessive daytime sleepiness with irresistible sleep attacks, cataplexy (sudden bilateral loss of muscle tone), hypnagogic hallucination, and sleep paralysis. There are two distinct groups of patients, ie, those having narcolepsy with cataplexy and those having narcolepsy without cataplexy. Narcolepsy affects 0.05% of the population. It has a negative effect on the quality of life of its sufferers and can restrict them from certain careers and activities. There have been advances in the understanding of the pathogenesis of narcolepsy. It is thought that narcolepsy with cataplexy is secondary to loss of hypothalamic hypocretin neurons in those genetically predisposed to the disorder by possession of human leukocyte antigen DQB1*0602. The diagnostic criteria for narcolepsy are based on symptoms, laboratory sleep tests, and serum levels of hypocretin. There is no cure for narcolepsy, and the present mainstay of treatment is pharmacological treatment along with lifestyle changes. Some novel treatments are also being developed and tried. This article critically appraises the evidence for diagnosis and treatment of narcolepsy.

Narcolepsy in Parkinson's disease

Non-motor symptoms in Parkinson's disease (PD), such as excessive daytime sleepiness, 'sleep attacks', insomnia, restless legs syndrome and rapid eye movement sleep behavior disorder, are common and provide a challenge to treatment. These sleep symptoms are also described in patients suffering from the sleep/wake disorder, narcolepsy. The International Classification of Sleep Disorders (ICSD-2) narcolepsy criteria uses a number of markers for diagnosis, of which lack or deficiency of cerebrospinal fluid (CSF) hypocretin-1 levels is a key marker. Hypocretin neurons prominently located in the lateral hypothalamus and perifornical nucleus have been proposed to interact with mechanisms involving sleep and arousal. Low hypocretin-1 levels in the CSF have been shown to correlate with hypothalamic hypocretin cell loss in narcolepsy and other forms of hypersomnia; therefore, it has been proposed that degenerative damage to hypocretin neurons (such as in PD) may be detected by low CSF hypocretin-1 concentrations, and may also explain the sleep symptoms experienced by some PD patients. To date, there is mixed conflicting data describing hypocretin-1 levels in the CSF of patients with parkinsonism associated with sleep symptoms, with most studies showing no significant decrease when compared with controls. However, hypocretin-1 CSF deficiency has been shown in some studies to be more prominent in PD patients with sleep symptoms versus those without. Notably, the hypocretin system has been shown not to be selectively disrupted, with one study showing melanin concentrating hormone cell loss in the same patients with hypocretin loss. It is likely that hypocretin deficiency in PD patients occurs secondary to collateral damage caused by the neurodegenerative process involving the hypothalamus. Awareness of narcoleptic events in PD is important for driving related advice, in addition to the possible use of dopamine D3 receptor active agonists.

Modafinil: past, present and future

Modafinil is a novel wake-promoting agent approved for the treatment of excessive sleepiness associated with narcolepsy that holds significant promise as an alternative treatment to traditional psychostimulants for excessive fatigue associated with medical and psychiatric disorders and as augmentation medication for treatment-resistant depression.

Treatment of narcolepsy

Narcolepsy is a neurological disorder characterized, in its classical form, by excessive daytime sleepiness (EDS) with irresistible episodes of sleep, cataplexy, disrupted nocturnal sleep, hypnagogic/hypnopompic hallucinations and sleep paralysis. It is often under-diagnosed, however, if it is suitably diagnosed, symptoms can be well treated by means of targeted drugs, such as modafinil to treat EDS, sodium oxybate for cataplexy, as well as EDS and disrupted nocturnal sleep, and tricyclic and newer antidepressants for cataplexy. Hallucinations and sleep paralysis can be treated with the same drugs used for cataplexy. Amphetamines and amphetamine-like stimulants are used less nowadays. Behavioral measures are also important and useful. The discovery of hypocretin deficiency in narcoleptic patients opens new perspectives for the development of newer therapeutic approaches for both EDS and cataplexy. Therapy for narcolepsy is chronic, hence symptomatic. However, the correct use of available drugs enables patients to gain a better quality of life, keeping the symptoms under control, which, mainly from a social point of view, are heavily disabling.

Narcolepsy and depression and the neurobiology of gammahydroxybutyrate

A voluminous literature describes the relationship between disturbed sleep and depression. The breakdown of sleep is one of the cardinal features of depression and often also heralds its onset. Frequent arousals, periods of wakefulness and a short sleep onset REM latency are typical polysomnographic features of depression. The short latency to REM sleep has been attributed to the combination of a monoaminergic deficiency and cholinergic supersensitivity and these irregularities have been proposed to form the biological basis of the disorder. A similar imbalance between monoaminergic and cholinergic neurotransmission has been found in narcolepsy, a condition in which frequent awakenings, periods of wakefulness and short sleep onset REM latencies are also characteristic findings during sleep. In many cases of narcolepsy, this imbalance appears to result from a deficiency of hypocretin but once established, whether in depression or narcolepsy, this disequilibrium sets the stage for the dissociation or premature appearance of REM sleep and for the dissociation of the motor inhibitory component of REM sleep or cataplexy. In the presence of this monoaminergic/cholinergic imbalance, gammahydroxybutyrate (GHB) may acutely further reduce the latency of REM sleep and induce cataplexy, in both patients with narcolepsy or depression. On the other hand, the repeated nocturnal application of GHB in patients with narcolepsy improves the continuity of sleep, prolongs the latency to REM sleep and prevents cataplexy. Evidence to date suggests that GHB may restore the normal balance between monoaminergic and cholinergic neurotransmission. As such, the repeated use of GHB at night and the stabilization of sleep over time makes GHB an effective treatment for narcolepsy and a potentially effective treatment for depression.

The effect of modafinil on cognitive function in breast cancer survivors

BACKGROUND

The authors conducted a randomized clinical trial examining the effects of modafinil in reducing persistent fatigue in patients after treatment for cancer and performed secondary analyses to assess the effect of modafinil on cognitive function.

METHODS

Breast cancer patients who reported a score of >or=2 on the Brief Fatigue Inventory were enrolled in the study. In phase 1 (P1), patients received 200 mg modafinil open-label once daily for 4 weeks. In phase 2 (P2), patients with a positive response after P1 were randomized either to an additional 4 weeks of modafinil or to placebo. Tests of memory and attention selected from the Cognitive Drug Research (CDR) computerized cognitive assessment were performed at baseline (before modafinil) and after completing phases 1 and 2. The paired differences for each test score were subjected to a Wilcoxon signed rank test.

RESULTS

Of the 82 women who were enrolled, 76 completed P1, and 68 completed all assessments in the study. Modafinil had a significant effect on the Speed of Memory (P = .0073) and Quality of Episodic Memory (P < .0001) during P1 of the study. After randomization at Week 8, those patients who continued modafinil demonstrated significantly greater improvement in Speed of Memory (P = .029), Quality of Episodic Memory (P = .0151), and mean Continuity of Attention (P = .0101) relative to the group that was switched to placebo.

CONCLUSIONS

The authors found that modafinil improved cognitive performance in breast cancer survivors by enhancing some memory and attention skills. Although confirmation is needed, these findings suggest that modafinil may enhance quality of life in this patient population.

Modafinil improves information processing speed and increases energetic resources for orientation of attention in narcoleptics: double-blind, placebo-controlled ERP studies with low-resolution brain electromagnetic tomography (LORETA)

BACKGROUND AND PURPOSE

Recent neuroimaging studies in narcolepsy discovered significant gray matter loss in the right prefrontal and frontomesial cortex, a critical region for executive processing. In the present study, event-related potential (ERP) low-resolution brain electromagnetic tomography (LORETA) was used to investigate cognition before and after modafinil as compared with placebo.

PATIENTS AND METHODS

In a double-blind, placebo-controlled cross-over design, 15 patients were treated with a 3-week fixed titration scheme of modafinil and placebo. The Epworth Sleepiness Scale (ESS), Maintenance of Wakefulness Test (MWT) and auditory ERPs (odd-ball paradigm) were obtained before and after the 3 weeks of therapy. Latencies, amplitudes and LORETA sources were determined for standard (N1 and P2) and target (N2 and P300) ERP components.

RESULTS

The ESS score improved significantly from 15.4 (+/- 4.0) under placebo to 10.2 (+/- 4.1) under 400mg modafinil (p=0.004). In the MWT, latency to sleep increased nonsignificantly after modafinil treatment (11.9+/-6.9 versus 13.3+/-7.1 min). In the ERP, N2 and P300 latencies were shortened significantly. While ERP amplitudes showed only minor changes, LORETA revealed increased source strengths: for N1 in the left auditory cortex and for P300 in the medial and right dorsolateral prefrontal cortex.

CONCLUSION

LORETA revealed that modafinil improved information processing speed and increased energetic resources in prefrontal cortical regions, which is in agreement with other neuroimaging studies.

Modafinil in the treatment of excessive sleepiness

The wake-promoting agent modafinil is approved for the treatment of excessive sleepiness associated with obstructive sleep apnea (OSA), shift work disorder (SWD), and narcolepsy. In OSA, modafinil is recommended for use as an adjunct to standard therapies that treat the underlying airway obstruction. This article reviews the literature on modafinil (pharmacology, pharmacokinetics, efficacy, tolerability, and abuse potential), with emphasis on use of modafinil in the treatment of excessive sleepiness in patients with OSA, SWD, and narcolepsy. In large-scale, double-blind, placebo-controlled studies, modafinil improved objectively determined sleep latency, improved overall clinical condition related to severity of sleepiness, and reduced patient-reported sleepiness. Improvements in wakefulness were accompanied by improvements in behavioral alertness, functional status, and health-related quality of life. In patients with SWD, diary data showed modafinil reduced the maximum level of sleepiness during night shift work, level of sleepiness during the commute home, and incidence of accidents or near-accidents during the commute home when compared with placebo. Modafinil was well tolerated, without adversely affecting cardiovascular parameters or scheduled sleep. These findings and those of extension studies which reported improvements were maintained suggest modafinil has a beneficial effect on daily life and well-being in patients with excessive sleepiness associated with OSA, SWD, or narcolepsy.

Modafinil: a review of neurochemical actions and effects on cognition

Modafinil (2-[(Diphenylmethyl) sulfinyl] acetamide, Provigil) is an FDA-approved medication with wake-promoting properties. Pre-clinical studies of modafinil suggest a complex profile of neurochemical and behavioral effects, distinct from those of amphetamine. In addition, modafinil shows initial promise for a variety of off-label indications in psychiatry, including treatment-resistant depression, attention-deficit/hyperactivity disorder, and schizophrenia. Cognitive dysfunction may be a particularly important emerging treatment target for modafinil, across these and other neuropsychiatric disorders. We aimed to comprehensively review the empirical literature on neurochemical actions of modafinil, and effects on cognition in animal models, healthy adult humans, and clinical populations. We searched PubMed with the search term 'modafinil' and reviewed all English-language articles for neurochemical, neurophysiological, cognitive, or information-processing experimental measures. We additionally summarized the pharmacokinetic profile of modafinil and clinical efficacy in psychiatric patients. Modafinil exhibits robust effects on catecholamines, serotonin, glutamate, gamma amino-butyric acid, orexin, and histamine systems in the brain. Many of these effects may be secondary to catecholamine effects, with some selectivity for cortical over subcortical sites of action. In addition, modafinil (at well-tolerated doses) improves function in several cognitive domains, including working memory and episodic memory, and other processes dependent on prefrontal cortex and cognitive control. These effects are observed in rodents, healthy adults, and across several psychiatric disorders. Furthermore, modafinil appears to be well-tolerated, with a low rate of adverse events and a low liability to abuse. Modafinil has a number of neurochemical actions in the brain, which may be related to primary effects on catecholaminergic systems. These effects are in general advantageous for cognitive processes. Overall, modafinil is an excellent candidate agent for remediation of cognitive dysfunction in neuropsychiatric disorders.

Treatment of narcolepsy and other hypersomnias of central origin

OBJECTIVE

The purpose of this paper is to summarize current knowledge about treatment of narcolepsy and other hypersomnias of central origin.

METHODS

The task force performed a systematic and comprehensive review of the relevant literature and graded the evidence using the Oxford grading system. This paper discusses the strengths and limitations of the available evidence regarding treatment of these conditions, and summarizes key information about safety of these medications. Our findings provide the foundation for development of evidence-based practice parameters on this topic by the Standards of Practice Committee of the American Academy of Sleep Medicine.

RESULTS

The majority of recent papers in this field provide information about use of modafinil or sodium oxybate for treatment of sleepiness associated with narcolepsy. Several large randomized, placebo-controlled studies indicate that modafinil and sodium oxybate are effective for treatment of hypersomnia due to narcolepsy. We identified no studies that report direct comparison of these newer medications versus traditional stimulants, or that indicate what proportion of patients treated initially with these medications require transition to traditional stimulants or to combination therapy to achieve adequate alertness. As with the traditional stimulants, modafinil and sodium oxybate provide, at best, only moderate improvement in alertness rather than full restoration of alertness in patients with narcolepsy. Several large randomized placebo-controlled studies demonstrate that sodium oxybate is effective for treatment of cataplexy associated with narcolepsy, and earlier studies provide limited data to support the effectiveness of fluoxetine and tricyclic antidepressants for treatment of cataplexy. Our findings indicate that very few reports provide information regarding treatment of special populations such as children, older adults, and pregnant or breastfeeding women. The available literature provides a modest amount of information about improvement in quality of life in association with treatment, patient preferences among the different medications, or patient compliance.

CONCLUSION

Several recent studies provide evidence that modafinil and sodium oxybate are effective for treatment of hypersomnia due to narcolepsy. No studies were identified that report direct comparison of these newer medications with traditional stimulants. Despite significant advances in understanding the pathophysiology of narcolepsy, we do not have an ideal treatment to restore full and sustained alertness. Future investigations should be directed toward development of more effective and better tolerated therapies, and primary prevention.

Efficacy of caffeine and modafinil in counteracting sleep deprivation in the marmoset monkey

BACKGROUND AND PURPOSE

The effects of sleep deprivation are a burden in our 24-h society. The use of wake-promoting compounds could improve the performance in situations where sleep cannot be allowed. In this study, the efficacy of the wake-promoting compounds, modafinil and caffeine, in counteracting the effects of 24-h sleep deprivation in the marmoset monkey were tested. As caffeine is habitually used, the efficacy of both compounds after short- and long-term use was investigated.

MATERIALS AND METHODS

After a normal active day, the animals were kept awake and received wake-promoting compounds during the whole night. Three times during the sleep-deprived night, putative fatigue was assessed with an activity test and the vigilance and ability to execute a task was assessed with a hand-eye coordination (HEC) task.

RESULTS

Both compounds were able to counteract to some extent the decline in performance. Modafinil was able to keep the activity at baseline performance, but performance on the HEC task was not improved. Caffeine was able to keep performance in the HEC task at a level just below daytime level but was not able to keep activity at daytime levels during the last part of the night. Caffeine and modafinil administration for 2 weeks showed a comparable effect on activity as acute use. The performance on the HEC task was similar after chronic caffeine and improved after chronic modafinil.

CONCLUSION

It is therefore concluded that modafinil and caffeine were both able to postpone or prevent the decline in vigilance and psychomotor performance and increase in fatigue induced by sleep deprivation.

Therapies for narcolepsy with or without cataplexy: evidence-based review

(1) Narcolepsy is a rare disorder of unknown aetiology characterized by excessive daytime sleepiness and typically associated with cataplexy. It is extremely incapacitating, and frequently results in impaired psychosocial functioning and reduced work performance. Currently there is no cure for narcolepsy, so treatment focuses on control of symptoms.(2) Although the sympathomimetic stimulants, such as amphetamines or methylphenidate, are effective in improving excessive daytime sleepiness in patients with narcolepsy, they have the potential for dependence, have sometimes disabling sympathomimetic side-effects and are associated with tolerance.(3) To date, there is clear evidence of the efficacy of modafinil, armodafinil and sodium oxybate in patients with narcolepsy. Modafinil and armodafinil improve excessive daytime sleepiness symptoms and have little abuse potential, but have no effect on cataplexy, so other drugs, such as antidepressants, are required to control cataplexy attacks.(4) Sodium oxybate improves both excessive daytime sleepiness and cataplexy. However, there is potential for abuse and possibly dependence.