ABSTRACT
The substantial challenges facing high and low dose psychedelic drug development to achieve regulatory approval have been documented in the scientific literature. These limitations have not deterred drug developers and social media from repeatedly misleading patients, the public and health professionals. Developing "micro doses" of psychedelics overcomes many of the scientific and regulatory challenges of high dose psychedelics. If micro-dosing could be shown to be efficacious and safe for long term use, it could be administered in the typical model for treatment of mental disorders. Such a model would be more cost effective than the high dose/intense psychotherapy model currently described and could be readily available to all individuals who need another medication option. Outpatient psychotherapeutic agents have a clear route for approval and would be unlikely to be burdened by the extensive Risks Evaluation and Mitigation Strategy needed for high dose use. There may be a different therapeutic role for both high and low dose psychedelic agents. This article is part of the Special Issue on "National Institutes of Health Psilocybin Research Speaker Series".
Subject(s)
Hallucinogens , Mental Disorders , Social Media , Humans , Hallucinogens/therapeutic use , Lysergic Acid Diethylamide/therapeutic use , Psilocybin/therapeutic use , Mental Disorders/drug therapyABSTRACT
Scientific curiosity and fascination have played a key role in human research with psychedelics along with the hope that perceptual alterations and heightened insight could benefit well-being and play a role in the treatment of various neuropsychiatric disorders. These motivations need to be tempered by a realistic assessment of the hurdles to be cleared for therapeutic use. Development of a psychedelic drug for treatment of a serious psychiatric disorder presents substantial although not insurmountable challenges. While the varied psychedelic agents described in this chapter share some properties, they have a range of pharmacologic effects that are reflected in the gradation in intensity of hallucinogenic effects from the classical agents to DMT, MDMA, ketamine, dextromethorphan and new drugs with activity in the serotonergic system. The common link seems to be serotonergic effects modulated by NMDA and other neurotransmitter effects. The range of hallucinogens suggest that they are distinct pharmacologic agents and will not be equally safe or effective in therapeutic targets. Newly synthesized specific and selective agents modeled on the legacy agents may be worth considering. Defining therapeutic targets that represent unmet medical need, addressing market and commercial issues, and finding treatment settings to safely test and use such drugs make the human testing of psychedelics not only interesting but also very challenging. This article is part of the Special Issue entitled 'Psychedelics: New Doors, Altered Perceptions'.
Subject(s)
Hallucinogens/pharmacology , Biomedical Research , Hallucinogens/adverse effects , Hallucinogens/pharmacokinetics , Hallucinogens/therapeutic use , Healthy Volunteers , HumansABSTRACT
All drugs with central nervous system activity must undergo an assessment of their abuse potential, and these data must be included in a New Drug Application. Part of this assessment is an analysis of treatment-emergent adverse events that occur during clinical development. Using an iterative consensus strategy, we evaluated and grouped an available list of 213 flag terms for abuse potential from the Food and Drug Administration, into categories and assessed the relevance of the terms to primary abuse behavior. Consequences of abuse (28%) were most common, followed by diagnoses (19%), altered thoughts (18%), cognitive effects (10%), stimulation/anxiety (9%), central nervous system depression (9%), and mood elevation (1%). The vast majority of abuse potential-related terms reflects treatment-emergent adverse events, not behaviorally motivating features to abuse a drug. Almost 30% of terms are related to altered perception or altered cognition. These are serious consequences in the context of abusable psychoactive drugs. Only 20% of terms were rated as definitely or probably reflecting intrinsic behavioral reinforcing potential, and 30% were assessed as having weak predictive utility. Sponsors need to have an explicit strategy for collecting, interpreting, and analyzing abuse-related adverse event information completely and accurately.
Subject(s)
Central Nervous System Agents/adverse effects , Drug Development , Substance-Related Disorders , Humans , Safety , Substance-Related Disorders/etiology , Substance-Related Disorders/prevention & control , Substance-Related Disorders/psychology , United States , United States Food and Drug AdministrationABSTRACT
OBJECTIVE: Many academic centers in North America are initiating global partnerships to build physician capacity in resource-poor countries. An opportunity arose to develop a pediatric program (Ukraine Paediatric Fellowship Program, UPFP) in Ukraine, a large European country in transition from a Soviet/communist political and social system. This entailed dealing with a centralized and rigid healthcare system based on the Semashko model of the former Soviet Union. METHODS: Our capacity-building model has several key features: endowed philanthropic funding for sustainability, bilateral exchange of knowledge, a focus primarily on pediatric brain disorders, and team building. Centers for partnering are selected on the basis of need, receptivity to change, and participants' fluency in English. Ukrainian physicians attend month-long observerships in Toronto, and biannual teaching visits are conducted by Canadian clinicians. RESULTS: Over 5 years, 7 teaching visits have taken place, and 20 physicians have trained at SickKids Hospital in Toronto. Six Ukrainian children's hospitals are now collaborating with UPFP. New surgical procedures have been introduced, such as endoscopic ventriculostomy and corpus callosotomy. Patient referrals to regional institutions have increased, and new projects that affect fetal and infant neurodevelopment have been initiated (e.g., treatment of perinatal maternal depression and folic acid fortification of flour). Ukrainian participants rate the program highly in their evaluations. CONCLUSIONS: In a short time, UPFP has had considerable success in increasing physician capacity for improved pediatric care in regions of Ukraine. The keys to success have included focusing locally, selecting trustable partners, building incrementally, and creating interspecialty synergies.
Subject(s)
Capacity Building , Neurosurgery/trends , Pediatrics/trends , Psychiatry/trends , Child , Delivery of Health Care , Health Services Accessibility , Health Status , Hospitals, Pediatric , Humans , Needs Assessment , Neurosurgery/education , Pediatrics/education , Program Evaluation , Psychiatry/education , USSR , UkraineABSTRACT
Psychoactive drugs that increase alertness, attention and concentration and energy, while also elevating mood, heart rate and blood pressure are referred to as stimulants. Despite some overlapping similarities, stimulants cannot be easily categorized by their chemical structure, mechanism of action, receptor binding profile, effects on monoamine uptake, behavioral pharmacology (e.g., effects on locomotion, temperature, and blood pressure), therapeutic indication or efficacy. Because of their abuse liability, a pre-market assessment of abuse potential is required for drugs that show stimulant properties; this review article focuses on the clinical aspects of this evaluation. This includes clinical trial adverse events, evidence of diversion or tampering, overdoses and the results of a human abuse potential study. While there are different types of human experimental studies that can be employed to evaluate stimulant abuse potential (e.g., drug discrimination, self-administration), only the human abuse potential study and clinical trial adverse event data are required for drug approval. The principal advances that have improved human abuse potential studies include using study enrichment strategies (pharmacologic qualification), larger sample sizes, better selection of endpoints and measurement strategies and more carefully considered interpretation of data. Because of the methodological advances, comparisons of newer studies with historical data is problematic and may contribute to a biased regulatory framework for the evaluation of newer stimulant-like drugs, such as A2 antagonists. This article is part of the Special Issue entitled 'CNS Stimulants'.
Subject(s)
Central Nervous System Stimulants/administration & dosage , Drug Evaluation/methods , Substance-Related Disorders , Clinical Trials as Topic , Humans , Self Administration , Substance-Related Disorders/diagnosis , Substance-Related Disorders/prevention & controlABSTRACT
The overarching goal of this event-related potential (ERP) study was to examine the effects of scopolamine on the dynamics of brain network activation using a novel ERP network analysis method known as Brain Network Activation (BNA). BNA was used for extracting group-common stimulus-activated network patterns elicited to matching probe stimuli in the context of a delayed matching-to-sample task following placebo and scopolamine treatments administered to healthy participants. The BNA extracted networks revealed the existence of two pathophysiological mechanisms following scopolamine, disconnection, and compensation. Specifically, weaker frontal theta and parietal alpha coupling was accompanied with enhanced fronto-centro-parietal theta activation relative to placebo. In addition, using the characteristic BNA network of each treatment as well as corresponding literature-guided selective subnetworks as combined biomarkers managed to differentiate between individual responses to each of the treatments. Behavioral effects associated with scopolamine included delayed response time and impaired response accuracy. These results indicate that the BNA method is sensitive to the effects of scopolamine on working memory and that it may potentially enable diagnosis and treatment assessment of dysfunctions associated with cholinergic deficiency.
Subject(s)
Cerebral Cortex/drug effects , Evoked Potentials, Visual , Memory, Short-Term/drug effects , Scopolamine/pharmacology , Adolescent , Adult , Alpha Rhythm , Cerebral Cortex/physiology , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Middle Aged , Theta Rhythm , Visual PerceptionABSTRACT
OBJECTIVE: This study aimed to evaluate the abuse potential and cognitive effects of nabiximols (Sativex, GW Pharma Ltd. Salisbury, UK), an oromucosal spray primarily containing delta9tetrahydrocannabinol (THC) and cannabidiol (CBD). METHODS: This was a singledose, randomized, doubleblind, crossover study comparing nabiximols (4, 8, and 16 consecutive sprays: 10.8, 21.6, and 43.2 mg THC, respectively) with dronabinol 20 and 40 mg (synthetic THC: Marinol, Solvay Pharmaceuticals, Brussels, Belgium) and matching placebos in 23 recreational cannabis users. Subjective and cognitive/psychomotor measures were administered over 24 h postdose. RESULTS: Dronabinol was significantly different from placebo on abuse potential measures, thereby confirming study validity. Nabiximols 10.8 mg was not significantly different from placebo on primary measures but was different on some secondary measures. Nabiximols 21.6 mg was significantly greater than placebo on some primary/secondary measures, whereas nabiximols 43.2 mg showed significant effects on most measures. Nabiximols 10.8 mg was significantly lower than dronabinol doses on most measures ( p < 0.05). Dronabinol 20 mg effects were numerically higher than nabiximols 21.6 mg but were statistically significant only for some measures. Dronabinol 40 mg and nabiximols 43.2 mg were generally not statistically different. CONCLUSIONS: Both dronabinol and nabiximols had significant abuse potential compared with placebo at higher doses. Nabiximols showed similar or slightly less abuse potential compared with dronabinol. Therefore, the abuse potential of nabiximols should be no higher than that of dronabinol.
Subject(s)
Cannabinoids/administration & dosage , Cognition/drug effects , Dronabinol/administration & dosage , Marijuana Abuse , Mouth Mucosa/drug effects , Plant Extracts/administration & dosage , Adult , Cannabidiol , Cannabinoids/blood , Cognition/physiology , Cross-Over Studies , Double-Blind Method , Dronabinol/blood , Drug Combinations , Drug Evaluation/methods , Female , Humans , Illicit Drugs/blood , Male , Marijuana Abuse/blood , Marijuana Abuse/epidemiology , Middle Aged , Mouth Mucosa/physiology , Oral Sprays , Plant Extracts/blood , Young AdultABSTRACT
The results of two single-blind studies conducted to evaluate the cognitive and psychomotor effects of eslicarbazepine acetate and oxcarbazepine following single and repeated administration in healthy volunteers are reported. The cognitive and psychomotor evaluation consisted of several computerized and paper-and-pencil measures. Eslicarbazepine acetate and oxcarbazepine had similar overall cognitive profiles and did not cause clinically relevant cognitive impairment. The incidence of adverse events was lower with eslicarbazepine acetate than with oxcarbazepine.
Subject(s)
Anticonvulsants/pharmacology , Carbamazepine/analogs & derivatives , Cognition/drug effects , Dibenzazepines/pharmacology , Psychomotor Performance/drug effects , Adult , Attention/drug effects , Blood Pressure/drug effects , Carbamazepine/pharmacology , Dose-Response Relationship, Drug , Drug Administration Schedule , Follow-Up Studies , Heart Rate/drug effects , Humans , Learning/drug effects , Middle Aged , Neuropsychological Tests , Oxcarbazepine , Reaction Time/drug effects , Single-Blind Method , Statistics, Nonparametric , Young AdultABSTRACT
INTRODUCTION: While prescription opioids can improve quality of life through pain relief they are susceptible to misuse. This field study characterizes the relative susceptibility and attractiveness of a new analgesic patch, with fentanyl embedded in a matrix material, compared to other opioid dose formulations. METHODS: Recreational opioid abusers (N = 42; 31 male, 1 female)from three Canadian sites participated in structured interviews. They were presented with nine products, some of which were hypothetical (fentanyl [F], hydromorphone [H], and oxycodone [O] in each of three formulations: matrix patch [M], reservoir-type gel patch [G], and tablet [T]). The attractiveness and tampering potential of each product was ranked using two 7-point Likert scales (Value of Product and Likelihood to Tamper), an index representing the product of the two scales, a 17-item Opiate Attractiveness Scale (OAS), relative street value, and rank order of overall desirability. Non-parametric analyses were used to compare each product to the FM. RESULTS: The FT, HT, and FM were highly valued and most likely to be tampered with. The products were ranked in decreasing order of desirability as follows: FT > HT > FM > FG > OT > HM > HG > OM > OG. On the OAS, FM was more attractive than all gel-patch products (p < 0.001), and OT was most attractive overall. FM was statistically similar to OT, FT, OM, and HT. Of the 42 subjects, 25 (60 percent) preferred the matrix patch to the gel patch. Of the 17 subjects who preferred the gel patch, 10 (59 percent) were from a region generally unfamiliar with that formulation. CONCLUSIONS: Fentanyl is attractive to opioid abusers regardless of formulation. In Canada, a fentanyl matrix patch may be at higher risk for diversion, tampering, and abuse than other transdermal opioid formulations. These findings should be confirmed by epidemiological studies. Comparative risk management programs should be part of the development of any new narcotic delivery system.
Subject(s)
Analgesics, Opioid/administration & dosage , Substance-Related Disorders/psychology , Adult , Analgesics, Opioid/adverse effects , Canada , Dosage Forms , Drug Delivery Systems , Female , Gels , Humans , Interviews as Topic , Male , Middle Aged , TabletsABSTRACT
Allopregnanolone (ALLO) and pregnanolone (PREG), the 3alpha-reduced metabolites of progesterone (PROG), are potent modulators of gamma-aminobutyric acid type A receptors that may function as endogenous anxiolytics. They are purported to be involved in the etiology or expression of clinical depression. In the present study we quantified ALLO and PREG, as well as PROG, 5alpha-dihydroprogesterone (5alpha-DHP), 5beta-dihydroprogesterone (5beta-DHP), epiallopregnanolone and pregnenolone (PREGNEN), in plasma from healthy women at five time points during pregnancy and the postpartum period. Analysis was by gas chromatography/electron capture - negative chemical ionization - mass spectrometry. Neuroactive steroids increased significantly from 10 to 36 weeks of pregnancy, except for 5beta-DHP and PREGNEN which did not change significantly. PROG was the most abundant steroid throughout pregnancy, followed by 5alpha-DHP and ALLO. Metabolite to precursor ratios differed depending on the enzyme and substrate: the turnover of PROG to 5alpha-DHP (catalyzed by 5alpha-reductase) was stable while the conversion of PROG to 5beta-DHP (catalyzed by 5beta-reductase) decreased later in pregnancy. 3alpha-Hydroxysteroid oxidoreductase-mediated turnover of 5alpha- and 5beta-DHP to their metabolites ALLO and PREG, respectively, rose during pregnancy, but the turnover of 5alpha-DHP to ALLO dropped at the late prenatal visit. At 6 weeks postpartum all steroids were significantly reduced compared with late prenatal values, with 5alpha-DHP being the most abundant postpartum steroid. These results provide the basis for further study of neuroactive steroids in psychiatric conditions of pregnancy and the postpartum period.
Subject(s)
Postpartum Period/physiology , Pregnanolone/blood , Progesterone/blood , 5-alpha-Dihydroprogesterone/blood , Adult , Delivery, Obstetric/methods , Depression, Postpartum/blood , Female , Gas Chromatography-Mass Spectrometry , Gestational Age , Humans , Labor Onset/blood , Parity , Pregnancy , Pregnenolone/bloodABSTRACT
While serotonin 5HT2-receptors have been implicated in the etiology and pharmacological treatment of a number of neuropsychiatric conditions, there are few potent and specific agents available for use in human clinical studies. EMD 281014 is a highly specific 5HT2-receptor antagonist that is currently under development. To find optimal doses for early clinical studies, we conducted a PET study using [18F]setoperone in nine healthy subjects scanned at baseline and following the administration of 1, 3, and 7 mg EMD 281014. The study drug was well tolerated by all study participants, and all doses resulted in > or =70% occupancy at frontal 5HT2-receptors 3 h after drug administration. The data suggest that daily dosing of > or =3 mg EMD 281014 should be sufficient to provide sustained high levels of 5HT2-receptor occupancy in future clinical trials.
Subject(s)
Indoles/administration & dosage , Piperazines/administration & dosage , Serotonin 5-HT2 Receptor Antagonists , Adult , Dose-Response Relationship, Drug , Female , Fluorine Radioisotopes , Frontal Lobe/metabolism , Humans , Indoles/metabolism , Male , Middle Aged , Piperazines/metabolism , Positron-Emission Tomography , Pyrimidinones , Radiopharmaceuticals , Receptors, Serotonin, 5-HT2/metabolismABSTRACT
OBJECTIVES: Alcohol dependence is a prevalent psychiatric disorder affecting approximately 12% of the adult population at some point in their lifetime. Psychosocial treatments are associated with only modest success rates. The first Canadian clinical trial with naltrexone, an opiate antagonist, was conducted to evaluate its safety and usefulness as an adjunctive treatment in the management of alcohol dependence. METHODS: One hundred twenty alcohol-dependent individuals were assessed to receive treatment with 50 mg of naltrexone orally for 12 weeks in an open-label trial. Patients were seen biweekly and received a concurrent psychosocial intervention. Treatment was conducted at multiple sites in Canada. RESULTS: Fifty-four per cent of subjects completed the entire 12 weeks of treatment. During the study, 39% of patients abstained, while of the individuals reporting drinking at baseline, 86% were consuming less alcohol by their final visit. These reductions were accompanied by a significant decrease in craving for alcohol at week 12, as measured by the Obsessive Compulsive Drinking Scale (P<0.01). Naltrexone was well tolerated and no serious adverse events were experienced. CONCLUSIONS: The data lend support to the hypothesis that endogenous opioid activity is involved in the regulation of alcohol intake, and that antagonists of endogenous opioids decrease craving and drinking. Opiate antagonists such as naltrexone are a new strategy in the treatment of alcohol dependence. Naltrexone can be safely given to female and male alcoholics, is acceptable to patients, and plays a role in reducing alcohol consumption and preventing relapse to heavy drinking.
Subject(s)
Alcohol Deterrents/pharmacology , Alcohol Deterrents/therapeutic use , Alcoholism/drug therapy , Naltrexone/pharmacology , Naltrexone/therapeutic use , Adult , Alcohol Deterrents/adverse effects , Canada , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Naltrexone/adverse effectsABSTRACT
Codeine is O-demethylated by cytochrome P450 2D6 (CYP2D6) to form the more potent drug morphine, accounting for much of codeine's analgesic and dependence-producing properties. Because morphine production can be decreased by inhibition of CYP2D6, the authors hypothesized that CYP2D6 inhibition could be used to treat codeine dependence. A randomized, double-blind, placebo-controlled trial was conducted. All patients received brief behavioral therapy. Two weeks of baseline monitoring were followed by 8 weeks of daily treatment with fluoxetine or quinidine (two potent CYP2D6 inhibitors) or placebo. Thirty patients were assessed (all white, age 40 + 12 years using 127 + 79 mg/day of codeine [mean + SD]), and 17 entered treatment. Eight patients remained in the study by treatment week 8. Quinidine > fluoxetine > placebo inhibited CYP2D6 as reflected in the change of the O-demethylation of dextromethorphan, a specific CYP2D6 probe. At treatment week 8, placebo, quinidine, and fluoxetine reduced mean daily codeine intake by 57%, 56%, and 51% of baseline intake respectively; there was no difference among treatment groups. In this small sample, CYP2D6 inhibitors did not appear to have a useful role in the treatment of codeine dependence.