Leveraging Human Plasma-Derived Small Extracellular Vesicles as Liquid Biopsy to Study the Induction of Cytochrome P450 3A4 by Modafinil

Preparations of plasma-derived small extracellular vesicles (sEVs) were deployed as liquid biopsy to study cytochrome P450 (CYP) 3A4 (CYP3A4) induction following modafinil 400 mg once daily × 14 days (young healthy volunteers, N = 10 subjects). Induction was confirmed using the 4β-hydroxycholesterol-to-cholesterol (4βHC/C) ratio, a plasma CYP3A4/5 biomarker, with a mean 2.1-fold increase (Day 15 vs. Day 1; 90% confidence interval (CI) = 1.8-2.3; P value = 0.0004). Proteomic analysis revealed the induction (mean Day 15 vs. Day 1 fold-increase (90% CI)) of both liver (1.3 (1.1-1.5), P value = 0.014) and nonliver (1.9 (1.6-2.2), P value = 0.04) sEV CYP3A4 protein expression. In CYP3A5 nonexpresser subjects, the baseline (pre-dose) 4βHC/C plasma ratio was more highly correlated with liver sEVs (r = 0.937, P value = 0.001) than nonliver sEVs (r = 0.619, P value = 0.101) CYP3A4 protein expression. When CYP3A5 expressers (CYP3A5*1/*3) were included, the correlation with liver sEVs (r = 0.761, P value = 0.011) and nonliver sEVs (r = 0.391, P value = 0.264) CYP3A4 protein was weaker. Although modafinil-induced changes in plasma 4βHC/C ratio did not correlate with sEVs CYP3A4 protein expression, the individual subject sEVs proteomic data were used successfully to predict victim drug (midazolam, triazolam, dextromethorphan, 17α-ethinylestradiol, and abemaciclib) area under the plasma concentration-time curve (AUC) ratios (AUCRs) following modafinil. Based on the AUCR values, modafinil was classified as a weak to moderate CYP3A4 inducer (vs. rifampicin). For the first time, it was possible to deploy plasma-derived sEVs to study CYP3A4 induction beyond rifampicin, a more potent CYP3A4 inducer.

Wake-Promoting and EEG Spectral Effects of Modafinil After Acute or Chronic Administration in the R6/2 Mouse Model of Huntington's Disease

Huntington's disease (HD) is characterised by progressive symptoms including cognitive deficits and sleep/wake disturbances reflected in an abnormal electroencephalography (EEG). Modafinil, a wake-promoting and cognitive-enhancing drug, has been considered as a treatment for HD. We used HD (R6/2) mice to investigate the potential for using modafinil to treat sleep-wake disturbance in HD. R6/2 mice show sleep-wake and EEG changes similar to those seen in HD patients, with increased rapid eye movement sleep (REMS), decreased wakefulness/increased non-REMS (NREMS), and pathological changes in EEG spectra, particularly an increase in gamma power. We recorded EEG from R6/2 and wild-type mice treated with modafinil acutely (with single doses between 25 and 100 mg/kg; at 12 and 16 weeks of age), or chronically (64 mg/kg modafinil/day from 6 to 15 weeks). Acutely, modafinil increased wakefulness in R6/2 mice and restored NREMS to wild-type levels at 12 weeks. It also suppressed the pathologically increased REMS. This was accompanied by decreased delta power, increased peak frequency of theta, and increased gamma power. At 16 weeks, acute modafinil also restored wakefulness and NREMS to wild-type levels. However, whilst REMS decreased, it did not return to normal levels. By contrast, in the chronic treatment group, modafinil-induced wakefulness was maintained at 15 weeks (after 9 weeks of treatment). Interestingly, chronic modafinil also caused widespread suppression of power across the EEG spectra, including a reduction in gamma that increases pathologically in R6/2 mice. The complex EEG effects of modafinil in R6/2 mice should provide a baseline for further studies to investigate the translatability of these result to clinical practice.

A randomized pragmatic trial of telephone-delivered cognitive behavioral-therapy, modafinil, and combination therapy of both for fatigue in multiple sclerosis: The design of the "COMBO-MS" trial

BACKGROUND

Fatigue is one of the most common and disabling chronic symptoms in multiple sclerosis (MS). Optimization of available treatments for MS-related fatigue has been stymied by lack of comparative effectiveness research that focuses on real-world treatment delivery methods and potential modification of treatment effect by other chronic MS symptoms or disability level. This report describes the design of a patient centered, comparative effectiveness trial of cognitive behavioral-therapy (CBT), modafinil, and combination therapy of both for fatigue in MS ("COMBO-MS").

METHODS

We describe the methods of this pragmatic comparative effectiveness trial that is guided by a team of patient, family, provider, community, and payer stakeholders. Eligible participants with MS and significant fatigue severity are randomly assigned (1:1:1) to received either CBT, modafinil, or a combination of CBT and modafinil for 12 weeks. The primary outcome is change in fatigue impact as measured by the Modified Fatigue Impact Scale (MFIS) at 12 weeks. Secondary outcome measures include ecological momentary assessment (EMA) measures of fatigue intensity, fatigue interference, and fatigability (measured over 7 days' time at baseline and at 12 weeks), and change in MFIS score at 24 weeks.

PROJECTED OUTCOMES

We hypothesize that combination therapy will more effectively ameliorate fatigue severity than either monotherapy, and that heterogeneity of treatment effects will be found based on depression status, presence of known or suspected sleep disorder, and disease severity. Study findings will assist patients, providers, payers, and policy makers to provide more effective care for managing fatigue in MS.

Modafinil as a Stimulant for Military Aviators

INTRODUCTION: Modafinil is a wakefulness-promoting stimulant that has been approved by the Republic of Singapore Air Force (RSAF) as a fatigue countermeasure medication since 2011. Each RSAF aircrew member must undergo a ground test to exclude operationally relevant adverse drug effects prior to consuming the medication for operational reasons. This study describes the RSAF's modafinil ground testing outcomes over a 7-yr period.METHODS: This is a retrospective case series of 243 RSAF aircrew members who underwent modafinil 100-mg test dosing over the 7-yr period from September 2011 to September 2018.RESULTS: The median age was 31 yr (range, 21-53 yr) and mean age was 31.7 yr ± 6.19 yr. Of the aircrew members, 234 (96.3%) were men and all were of Asian ethnicity. Of the subjects, 237 (97.5%) were medically cleared for the operational use of modafinil. Among the six (2.47%) who failed modafinil ground testing, headache (cumulative incidence, 1.65%), anxiety (cumulative incidence, 0.41%), diarrhea (cumulative incidence, 0.41%), and insomnia (cumulative incidence, 0.41%) were reported as the side effects experienced. None of the aircrew members experienced major adverse drug events.DISCUSSION: Our findings suggest a low occurrence of adverse drug effects among military aircrew members who undergo modafinil test dosing prior to using the drug operationally. To our knowledge, this is the single largest published case series of modafinil ground testing outcomes among Asian military aviators.Ooi T, Wong SH, See B. Modafinil as a stimulant for military aviators. Aerosp Med Hum Perform. 2019; 90(5):480-483.

[Use of Modafinil in Co-existing Major Depression and ErectileDysfunction: A Case Report]

Erectile dysfunction is a sexual dysfunction which is commonlycomorbid with major depression. Antidepressant treatment does notalways improve comorbid sexual dysfunctions in major depression. Infact, sexual dysfunction may worsen or get complicated following theintroduction of antidepressants. Modafinil is a drug with stimulanteffect on the central nervous system by binding to norepinephrineand dopamine transporters and consequently increasing synapticnorepinephrine and dopamine levels. Modafinil is primarily used inthe treatment of narcolepsy and chronic fatigue syndrome. In addition,it is known for its effectiveness in attention deficit hyperactivitydisorder and as an add-on option for major depression. In this paper,we report the case of a 39-year-old man with major depression whosecomorbid erectile dysfunction improved after addition of modafinilto antidepressant treatment. Fluoxetine 20 mg/day was initiatedand despite the improvement of most of the depressive symptomsand the sexual desire, his complaints of fatigue, weakness and erectiledysfunction continued. With the addition of modafinil (200 mg /day),improvement was observed not only in psychomotor symptoms but alsoin erectile dysfunction of the patient.

Cortico-Amygdala-Striatal Activation by Modafinil/Flecainide Combination

Background

Modafinil, a nonamphetaminic wake-promoting compound, is prescribed as first line therapy in narcolepsy, an invalidating disorder characterized by excessive daytime sleepiness and cataplexy. Although its mode of action remains incompletely known, recent studies indicated that modafinil modulates astroglial connexin-based gap junctional communication as administration of a low dose of flecainide, an astroglial connexin inhibitor, enhanced the wake-promoting and procognitive activity of modafinil in rodents and healthy volunteers. The aim of this study is to investigate changes in glucose cerebral metabolism in rodents, induced by the combination of modafinil+flecainide low dose (called THN102).

Methods

The impact of THN102 on brain glucose metabolism was noninvasively investigated using 18F-2-fluoro-2-deoxy-D-glucose Positron Emission Tomography imaging in Sprague-Dawley male rats. Animals were injected with vehicle, flecainide, modafinil, or THN102 and further injected with 18F-2-fluoro-2-deoxy-D-glucose followed by 60-minute Positron Emission Tomography acquisition. 18F-2-fluoro-2-deoxy-D-glucose Positron Emission Tomography images were coregistered to a rat brain template and normalized from the total brain Positron Emission Tomography signal. Voxel-to-voxel analysis was performed using SPM8 software. Comparison of brain glucose metabolism between groups was then performed.

Results

THN102 significantly increased regional brain glucose metabolism as it resulted in large clusters of 18F-2-fluoro-2-deoxy-D-glucose uptake localized in the cortex, striatum, and amygdala compared with control or drugs administered alone. These regions, highly involved in the regulation of sleep-wake cycle, emotions, and cognitive functions were hence quantitatively modulated by THN102.

Conclusion

Data presented here provide the first evidence of a regional brain activation induced by THN102, currently being tested in a phase II clinical trial in narcoleptic patients.

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.