A randomized clinical trial comparing doses and efficacy of lormetazepam tablets or oral solution for insomnia in a general practice setting

Lormetazepam is a short-acting benzodiazepine hypnotic which is beneficial in shortening the time to onset of sleep. The aim of the study was to assess a new formulation of lormetazepam (oral solution) in comparison with lormetazepam tablets in out-patients with insomnia. This trial was an open randomized parallel group study conducted by 30 general practitioners. One hundred and eight patients took 0.5 mg on the first night and were allowed to increase their dosage by 0.25 mg (for oral solution) and 0.5 mg (for tablets), respectively, each day and every 2 days. The patients assessed the efficacy, acceptability and tolerance of lormetazepam using a diary card and a set of visual analogue scales assessing their sleep. Over 14 days of treatment, the mean daily dose of lormetazepam was lower in the oral solution group than in the tablets group (0.78 mg versus 0.97 mg). The cumulated dose of lormetazepam was lower with the oral solution (18% reduction). No significant difference between the two groups was found in the assessment of sleep characteristics. The occurrence of side effects did not differ between the two groups. These results suggest that a unitary dose as achieved by an oral solution of lormetazepam allows easier determination of the minimal individual effective dose.

Amphetamine-like stimulant cessation in an abusing patient treated with bupropion

OBJECTIVE

Bupropion sustained release is considered to be a weak inhibitor of dopamine and serotonin reuptake.

METHOD

We report the case of an amphetamine-abusing patient who self-administered bupropion.

RESULTS

Since 30 years, a 52-year-old women used amphetamine derivates. She explained her need for amphetamine use in order to perform daily activities. Recently, she decided to experiment with bupropion. She abruptly stopped taking clobenzorex and simultaneously started taking bupropion (150 mg/day). The seventh day she reported a concomitant intake of clobenzorex; this induced adverse effects. Whilst taking bupropion, she described experiencing an euthymic state without any compulsion to take amphetamine drugs and was able to perform daily activities. After stopping it, no symptoms of withdrawal were reported by the patient.

CONCLUSION

This observation supports an another report suggesting that bupropion may be of help in weaning from amphetamine users and should be confirmed by clinical trials.

Weight gain profiles of new anti-psychotics: public health consequences

Anti-psychotic medications are an important therapeutic option for many individuals with schizophrenia. Recently, a growing interest has been observed on weight gain, which is now a well-known adverse effect of many anti-psychotics. As obesity is frequently a comorbid condition with schizophrenia, patients with schizophrenia are inherently at increased risk of developing obesity-related conditions such as cardiovascular disease and type 2 diabetes. The consequences of excessive weight gain (obesity) associated with anti-psychotic drugs are likely to include adverse effects on health, social burden and poor compliance or even discontinuation of therapy by the patients. In this article, we focus on different aspects of weight gain induced by anti-psychotics. This review comprises the following sections: (i) the pharmacological basis of anti-psychotic-induced weight gain and metabolic effects with a review of all anti-psychotics that can be used in patients with schizophrenia; (ii) the clinical impact of the body weight gain (morbidity, psychatric consequences, mortality); (iii) the management of obesity (identification of risk factors including pharmacogenetics, diet, behavioural therapies, pharmacological approach). An understanding of these aspects is important for those who prescribe anti-psychotics in order to provide the patient the best therapeutic management.

[Effects of a subanaesthetic dose of ketamine on emotional and behavioral state in healthy subjects]

Schizophrenic patients suffer from positive (delusions, hallucinations) and negative signs (social withdrawal) as well as emotional disturbance that included quantitative (blunted affect) and qualitative impairments (discordance of emotional level). Ketamine, a phencyclidine derivative, is a non competitive N-methyl-D-aspartate (NMDA) glutamate receptor antagonist. In healthy subjects its administration induces some positive symptoms (perceptual distortions.), negative symptoms (emotional deficit, apathy, social withdrawal) and cognitive changes (memory impairments and perseverations) that resemble some aspects of the symptoms of schizophrenia. A double blind cross over, placebo controlled was performed in 12 normal subjects with 2 sessions separated by one week of wash-out to determine ketamine-induced effects on behavioral and emotional responses. During each session, subjects received either ketamine or placebo (saline) infusion. A subanesthetic dose of ketamine (0,5 mg/kg) was administered by constant perfusion over 60 min. Behavioral and cognitive responses were assessed using positive and negative symptoms scales (BPRS, items from SAPS and SANS), vigilance and mood visual analog scale, subjective feelings using the Addiction Research Center Inventory (ARCI) and the Profile of Mood States (POMS). Using Philippot's method, emotions were elicited by films segments which induce a diversity of predictable emotions (fear, anger, sadness, joy, disgust and neutral state) and emotional responses were assessed by the Differential Emotions Scale (DES Izard). Low dose of ketamine induced significant effects on 7-items BPRS score (positive and negative items) and significant effects on positive and negative symptoms from SANS and SAPS. This was associated with emotional blunting of visually-induced responses that resemble aspects of schizophrenic emotional impairments. Ketamine impaired ARCI subscales (benzedrine subscale, pentobarbital-chlorpromazine subscale and LSD subscale). The recent findings of ketamine's pharmacology and imaging studies allow to draw several hypothesis related to neurotransmitter systems (glutamate, dopamine, serotonin interactions) and cerebral areas (particularly prefrontal cortex, anterior cingulate cortex, hippocampus) underlying some of these ketamine-induced effects.

[Treatment of non-dopamine-dependent signs in parkinsonian syndromes: evaluation and results]

With dopaminergic systems, non dopaminergic neurotransmission probably plays a major role in parkinsonian syndromes (Multiple System Atrophy, Progressive Supranuclear Palsy, Pure Autonomic Failure, Cortical basal degeneration, Lewy Body Disease). A better understanding of the pathophysiology of these syndromes led to the development of molecules that interact with non dopaminergic systems. Thus, freezing, gait and balance disorders, dysautonomia and neuropsychiatric disorders are likely to benefit from specific treatments. However, due to methodological difficulties related to the evaluation of such molecules, controlled trials are rather rare and the results are often partial and sometimes unclear.

Nonmotor fluctuations in Parkinson's disease: frequent and disabling

OBJECTIVE

To assess the frequency and disability caused by nonmotor fluctuations (NMF) in PD.

METHODS

A structured questionnaire was administered to 50 patients with PD with motor fluctuations (MF), focused on 54 nonmotor symptoms classified in three subgroups: 26 dysautonomic, 21 cognitive and psychiatric, and seven pain/sensory NMF. The link between each NMF and the motor state was determined. Patients were asked to grade their disability from 0 (no disability) to 4 (maximum discomfort) and to specify which kind of fluctuation subgroup (motor or nonmotor) was the most incapacitating. A statistical analysis was performed to determine the frequency of each NMF and to determine whether the level of disability resulting from NMF could be correlated to the main characteristics of the population.

RESULTS

All patients had had at least one type of NMF, most of which were associated with the "off" state. Anxiety (66%), drenching sweats (64%), slowness of thinking (58%), fatigue (56%), and akathisia (54%) were the most frequent NMF. Some symptoms such as anxiety or dyspnea correlated with a greater level of disability. The total number of NMF was found to be correlated with the motor disability. Incapacity resulting from the dysautonomic fluctuations was also significantly correlated with levodopa treatment. Surprisingly, 28% of the patients stated that NMF involved a greater degree of disability than MF.

CONCLUSION

Nonmotor fluctuations are frequent and debilitating in PD.

[Role of pharmacokinetic-pharmacodynamic relationships in drug development]

An important part of drug development relies on the analysis of the relationships between drug doses and therapeutic and/or side effects. This analysis implies an in-depth understanding of the pharmacokinetics (PK) and pharmacodynamics (PD) of the drug and of the relationship which links them (PK-PD relationship). The aim of this round table was to define the place of the study of PK-PD relationships in drug development. After reviewing the definitions of PK models, PD models, and of integrated PK-PD models, the article highlights the importance of studying the PK-PD relationship during the successive phases of drug development (pre-clinical, phase I/II, phase III) and in specific populations (children, elderly people). A number of examples taken from pharmaceutical development or international literature are given. They show the methodology used and the type of information which can be drawn at each step of drug development. The article also presents the difficulties which prevent a more systematic application of this kind of approach during drug development. Scientific limits, problems in relation with the misunderstanding of the approach both in academic institutions and in pharmaceutical companies, and difficulties related to the lack of specific guidelines are discussed. The conclusion emphasizes the importance of using PK-PD modeling all along drug development and presents a number of actions which could further broaden its use.

Risk propensity assessment in military special operations

Risk taking, decision making, and stress factors are strongly associated in military operations. The authors used the Bond and Lader mood and alertness scale and a new scale, Evaluation of Risks (EVAR), to assess risk proneness in a maritime counter-terrorism exercise. EVAR items are distributed among five factors: self-control, danger seeking, energy, impulsiveness, and invincibility. In the study, 10 pilots were submitted to strenuous night flights with limited sleep deprivation. Compared with baseline data, pilots reported an increase in impulsiveness, whereas EVAR factors were consistent in a control group composed of 9 navy crew member. Correlations were observed between mood and alertness and risk factors. These results illustrate how EVAR can be used to evaluate change in risk proneness in individuals submitted to various stressors. But further studies are required to weigh stress factors and environmental conditions in risk propensity with a larger population of various age and personality traits.

[Pharmacological modulation of the effects induced by ketamine at subanesthetic doses]

The similarity between ketamine effects and endogenous psychoses has created interest in the capacity of antipsychotic medications to block ketamine effects. In healthy subjects, a sub-anaesthetic single dose of lorazepam, typical neuroleptics, such as haloperidol, and atypical neuroleptics, such as clozapine and olanzapine, failed to block ketamine-induced positive and negative symptoms resembling schizophrenia. However, haloperidol is able to decrease ketamine-induced impairment in executive cognitive functions. Recently, lamotrigine reduced ketamine-induced psychotic symptoms, perceptual alterations, and cognitive impairments. In schizophrenic subjects, single doses of olanzapine do not decrease the effects of ketamine. However, long term treatment with clozapine has been reported to decrease ketamine-induced positive symptoms. Pharmacological modulation of the effects of NMDA receptor antagonists, such as ketamine, may lead to development of novel therapeutic agents for psychiatric illnesses such as schizophrenia.

Yawning

YAWNING IS A COMMON PHYSIOLOGICAL EVENT THAT CAN BE DIVIDED INTO THREE DISTINCT PHASES: a long inspiratory phase, a brief acme and a rapid expiration. The aim of yawning is not yet well defined. However this semi-voluntary event increases vigilance and aims to alert when drowsiness occurs. Yawning probably has an important role for social communication as well. Yawning can be responsible for pain, luxation or even transient ischaemic attack. Abnormal yawning is present in various pathologies: migraine, Parkinson's disease, tumours, psychiatric diseases, infections or iatrogenic pathologies. The neuro-pharmacology of yawning is complex and knowledge of its mechanisms is incomplete. While under the control of several neurotransmitters, yawning is largely affected by dopamine. Dopamine may activate oxytocin production in the paraventricular nucleus of the hypothalamus. Oxytocin may then activate cholinergic transmission in the hippocampus and, finally, acetylcholine might induce yawning via the muscarinic receptors of the effectors. This is an over-simplification; many other molecules can modulate yawning, such as nitric oxide, glutamate, GABA, serotonin, ACTH, MSH, sexual hormones and opium derivate peptides. Dopamine involvement in yawning could have practical applications in the study of new drugs or the exploration of neurological diseases such as migraine or psychosis. 2001 Harcourt Publishers Ltd

Neurobiology and clinical pharmacology of obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a brain disorder with recognizable periods of onset, course, familial occurrence, epidemiology, phenomenology, and treatment response. Several manifestations of pathophysiology are beginning to be defined, although they may represent intermediate pathophysiology rather than primary etiology. Positron emission tomography studies have consistently identified hypermetabolism in the orbitofrontal cortex, caudate nucleus, and, sometimes, anterior cingulate cortex. Neuropsychologic testing frequently identifies abnormalities in visuospatial function. Abnormal levels of cerebrospinal fluid neurotransmitters and neuromodulators are identifiable in untreated patients with OCD and return toward normal levels after effective treatment. The most consistent pathophysiologic finding in OCD points toward an abnormality in serotonin neurotransmission. Therapeutic response to selective serotonin reuptake inhibitors and the absence of improvement with norepinephrine reuptake inhibitors and dopamine antagonists argue strongly for a role of serotonin in the pathophysiology and treatment of OCD. Despite this clear indication from treatment trials, probes and manipulations of the serotonin system and its specific receptors have not provided a useful understanding of specific abnormalities. Clomipramine or potent selective serotonin reuptake inhibitors are the pharmacotherapy of choice for OCD, with a more limited role reserved for monoamine oxidase inhibitors. If one selective serotonin reuptake inhibitor is ineffective, others may be beneficial, in addition to the different proserotonergic and nonserotonergic augmentation strategies that could be useful in treatment of resistant OCD patients. Nondrug therapies are also important in OCD: behavioral therapy is frequently helpful and neurosurgery is sometimes helpful when other treatments fail.

A double blind parallel group placebo controlled comparison of sedative and mnesic effects of etifoxine and lorazepam in healthy subjects [corrected]

This paper describes the psychomotor and mnesic effects of single oral doses of etifoxine (50 and 100 mg) and lorazepam (2 mg) in healthy subjects. Forty-eight healthy subjects were included in this randomized double blind, placebo controlled parallel group study [corrected]. The effects of drugs were assessed by using a battery of subjective and objective tests that explored mood and vigilance (Visual Analog Scale), attention (Barrage test), psychomotor performance (Choice Reaction Time) and memory (digit span, immediate and delayed free recall of a word list). Whereas vigilance, psychomotor performance and free recall were significantly impaired by lorazepam, neither dosage of etifoxine (50 and 100 mg) produced such effects. These results suggest that 50 and 100 mg single dose of etifoxine do not induce amnesia and sedation as compared to lorazepam.

Antipsychotic-associated weight gain and clinical outcome parameters

Weight gain has been observed with many of the antipsychotics, including the atypical antipsychotics. The assessment of whether, and to what degree, a drug causes changes in body weight is not straightforward, since clinical studies performed during a drug development program are not designed to measure changes in body weight. Even when weight change data are obtained from adverse event data or from part of the vital signs measured during a study, assessment is not standardized. Nevertheless, evidence points to the fact that weight gain with the atypical antipsychotics is becoming an increasing problem. This review examines whether antipsychotic-associated weight gain, when it occurs, is associated with clinical outcome parameters.

N-methyl-D-aspartate receptors and information processing: human choice reaction time under a subanaesthetic dose of ketamine

Ketamine is an N-methyl-D-aspartate antagonist that induces cognitive dysfunctions. The purpose of the present study was to investigate the effects of a subanesthetic dose of ketamine on human information processing, using the additive factor method. During perfusion of a subanesthetic dose of ketamine (0.5 mg/kg over 60 min) or a placebo (randomized double-blind, cross-over design), eight adults (aged 22-33, mean=27) performed a two-choice visual reaction time (RT) task. Signal intensity, stimulus-response mapping, and foreperiod duration were manipulated. The effects of these three variables were found to be additive on RT, indicating that three independent stages - namely, stimulus preprocessing, response selection and motor selection- were manipulated. Ketamine altered RT performance in a specific way: it interacted with foreperiod duration but its effect was additive with those of signal intensity and stimulus-response mapping. These results show that ketamine specifically affects the stage of motor adjustment, which suggests that the glutamatergic system plays an important role in motor processes.

Controlled trial of 3-day quinine-clindamycin treatment versus 7-day quinine treatment for adult travelers with uncomplicated falciparum malaria imported from the tropics

We conducted a randomized, double-blind, placebo-controlled trial to compare a 3-day quinine-clindamycin regimen (group QC) with a 7-day quinine regimen (group Q) for the treatment of uncomplicated Plasmodium falciparum malaria in travelers returning from the tropics. A total of 55 and 53 patients in groups Q and QC were analyzed, respectively. Adverse effects were similar in both groups, although two patients in group Q had severe adverse reactions, leading to the cessation of treatment. The 28-day cure rate for the evaluated patients (per-protocol analysis) was 100% for group QC, whereas it was 96.3% for group Q (P = 0.5). The 28-day cure rate in the intention-to-treat analysis was 96.2% for group QC, whereas it was 94.6% for group Q (P = 1). There were no significant differences between the two regimens with regard to parasite and fever clearance times. Our study shows that the 3-day quinine-clindamycin regimen is well tolerated and compares favorably with a 7-day quinine treatment. This short-term regimen had previously been evaluated only in areas of endemicity. According to our results, the 3-day quinine-clindamycin regimen may be an alternative for the treatment of imported uncomplicated P. falciparum malaria in travelers returning from the tropics.

Pharmacokinetic and pharmacodynamic analysis of sedative and amnesic effects of lorazepam in healthy volunteers

This study describes for the first time the pharmacokinetic and pharmacodynamic modeling of the psychomotor and amnesic effects of a single 2-mg oral dose of lorazepam in healthy volunteers. Twelve healthy volunteers were included in this randomized, double-blinded, placebo-controlled two-way crossover study. The effect of lorazepam was examined for a battery of tests that explored mood, vigilance, psychomotor performance, and memory. The pharmacokinetic and pharmacodynamic modeling of these tests was performed using the indirect response model. Vigilance and psychomotor performance were significantly impaired. Short-term memory was not affected, but a paradoxical tendency to improvement of the score was observed 0.4 hours after drug intake. Significant impairment was observed for immediate and delayed cued verbal recall, for immediate and delayed free recall, and for picture recognition as well as for visual-verbal recall, but not for cued visual-spatial recall or priming. Globally, the different effects were greatest between 0.4 to 3 hours after dosing. However, the time course profile of the recovery period suggests a possible dissociation between the kinetics of the effects of lorazepam on vigilance, psychomotor performance, and visual episodic memory, on the one hand, and on verbal episodic memory, on the other. The pharmacokinetic and pharmacodynamic model used two compartments with first-order absorption to describe the lorazepam concentrations and an indirect response model with inhibition or stimulation of Kin to describe the effects. The mean values for calculated median effective concentration (EC50) derived from the pharmacokinetic and pharmacodynamic modeling of the different tests ranged from 11.3 to 39.8 ng/mL. According to these EC50 values, lorazepam seemed to be more potent on the delayed-recall trials than on the immediate-recall trials; similar observations were made concerning the free-recall versus cued-recall trials. The previously stated results suggest that the tests performed in this study represent sensitive measurements of the effects of lorazepam on the central nervous system. Moreover, the parameter values derived from pharmacokinetic and pharmacodynamic modeling, especially, the EC50 values, may provide sensitive indices that can be used to compare the central nervous system effects of benzodiazepines.

Levodopa-induced drowsiness in healthy volunteers: results of a choice reaction time test combined with a subjective evaluation of sedation

The aim of the present study was to assess levodopa (L-Dopa)-induced drowsiness in healthy volunteers using two parameters: choice reaction time and a subjective rating of sedation. Sixteen subjects participated in a randomized, double-blinded, crossover study. A single dose of 200 mg L-Dopa or placebo was administered at 9:00 AM. To limit peripheral side effects connected with L-Dopa, subjects were treated with 20 mg domperidone three times daily. Subjective rating of sedation consisted of visual analogue scale. Reaction time was measured by means of responses to two light-emitting diodes. The illumination of one of these diodes constituted the imperative signal. Manual responses were performed on two buttons located under the right and left index fingers. Results demonstrated a positive correlation between sedation level and reaction time (r = 0.70, p = 0.0026). Adverse events of L-Dopa were nausea (four cases) and excitation (one case). Subjects who did not develop adverse events were faster under L-Dopa than under placebo (p = 0.02), whereas subjects who had nausea or excitation were slower. A single dose of L-Dopa either deteriorated or improved choice reaction time in healthy volunteers according to whether it was sedative and whether it generated disruptive adverse events.

Pharmacokinetics of sabeluzole and dextromethorphan oxidation capacity in patients with severe hepatic dysfunction and healthy volunteers

AIMS

The primary objective of this study was to determine how the pharmacokinetics of sabeluzole, an investigational drug with specific effects on memory and learning abilities, are affected by chronic liver disease. Since sabeluzole is metabolised by CYP2D6, a secondary objective was to study the correlation between CYP2D6 activity (as assessed by the dextromethorphan dextrorphan metabolic ratio) and hepatic dysfunction.

METHODS

The single-dose pharmacokinetics of sabeluzole (10 mg) was compared in 10 healthy Caucasian subjects and 10 patients with severe hepatic dysfunction. The urinary dextromethorphan/dextrorphan (DMP/DRP) metabolic ratio was determined after intake of 20 mg dextromethorphan (NODEX capsules).

RESULTS

The terminal half-life of sabeluzole was significantly prolonged in subjects with severe hepatic dysfunction vs healthy subjects (respectively 39.3 +/- 11.5 h; 17.5 +/- 10.2 h (mean +/- s.d.)). The areas under the curve (AUC) were significantly higher in subjects with severe hepatic dysfunction than in healthy volunteers (681 +/- 200 ng ml(-1) h vs 331 +/- 282 ng ml(-1) h). There was a significant correlation between the AUC(0,infinity) and the DMP/DRP metabolic ratio in healthy volunteers and subjects with severe hepatic dysfunction. AUC was greater and elimination of sabeluzole slower in poor metabolizers compared with extensive metabolizers.

CONCLUSIONS

These results suggest that a) sabeluzole dose should be reduced in patients with severe hepatic dysfunction and b) the AUC of sabeluzole is linked to individual CYP2D6 activity.

Induction by dopamine D1 receptor agonist ABT-431 of dyskinesia similar to levodopa in patients with Parkinson disease

BACKGROUND

Dyskinesias are a frequent adverse effect of long-term levodopa therapy. The relative contribution of dopamine D(1) and D(2) receptor function to the pathophysiology of levodopa-induced dyskinesias remains a matter of controversy.

OBJECTIVE

To establish whether a selective D(1) dopamine agonist induces more or less dyskinesia than levodopa in primed dyskinetic patients with Parkinson disease.

METHODS

We studied ABT-431, the prodrug of a fully selective D(1) agonist, in 20 subjects with advanced Parkinson disease and a fluctuating response to levodopa complicated by dyskinesias. Eight patients were studied in a double-blind, randomized design (French centers); 12, in an open, randomized design (US centers). We assessed and compared the antiparkinsonian (Unified Parkinson's Disease Rating Scale) and dyskinetic (response induced by an acute challenge of a suprathreshold dose of levodopa and by 4 different ascending doses (5, 10, 20, and 40 mg) of ABT-431 during the 6 hours after the challenge.

RESULTS

The separate analysis of the double-blind and open data led to the same findings, ie, the antiparkinsonian and dyskinetic responses induced by ABT-431 were dose related. At the most effective doses (20 and 40 mg), ABT-431 exhibited similar antiparkinsonian benefit and produced similar dyskinesias as levodopa.

CONCLUSION

Dopamine D(1) agonists can induce a full antiparkinsonian response but do not support previous hypotheses suggesting that D(1) agonists are more or less likely to produce dyskinesias than levodopa.