Effects of MDMA-assisted therapy for PTSD on self-experience.

INTRODUCTION: There is a resurgence of interest in the therapeutic potential of psychedelic substances such as 3,4-methylenedioxymethamphetamine (MDMA). Primary findings from our randomized, double-blind, placebo-controlled, multi-site Phase 3 clinical trial of participants with severe PTSD (NCT03537014) showed that MDMA-assisted therapy induced significant attenuation in the Clinician-Administered PTSD Scale for DSM-5 compared to Therapy with placebo. Deficits in emotional coping skills and altered self-capacities constitute major obstacles to successful completion of available treatments. The current analysis evaluated the differential effects of MDMA-assisted therapy and Therapy with placebo on 3 transdiagnostic outcome measures and explored the contribution of changes in self-experience to improvement in PTSD scores. METHODS: Participants were randomized to receive manualized therapy with either MDMA or placebo during 3 experimental sessions in combination with 3 preparation and 9 integration therapy visits. Symptoms were measured at baseline and 2 months after the last experimental session using the 20-item Toronto Alexithymia Scale (TAS-20), the 26-item Self Compassion Scale (SCS), and the 63-item Inventory of Altered Self-Capacities (IASC). RESULTS: 90 participants were randomized and dosed (MDMA-assisted therapy, n = 46; Therapy with placebo, n = 44); 84.4% (76/90) had histories of developmental trauma, and 87.8% (79/90) had suffered multiple traumas. MDMA-assisted therapy facilitated statistically significant greater improvement on the TAS-20, the SCS, and most IASC factors of interpersonal conflicts; idealization disillusionment; abandonment concerns; identity impairment; self-awareness; susceptibility to influence; affect dysregulation; affect instability; affect skill deficit; tension reduction activities; the only exception was identity diffusion. CONCLUSION: Compared with Therapy with placebo, MDMA-assisted therapy had significant positive effects on transdiagnostic mental processes of self-experience which are often associated with poor treatment outcome. This provides a possible window into understanding the psychological capacities facilitated by psychedelic agents that may result in significant improvements in PTSD symptomatology.

Psychedelic drug abuse potential assessment research for new drug applications and Controlled Substances Act scheduling.

New medicines containing classic hallucinogenic and entactogenic psychedelic substance are under development for various psychiatric and neurological disorders. Many of these, including psilocybin, lysergic acid diethylamide (LSD), and 3,4-methylenedioxymethamphetamine (MDMA) are Schedule I controlled substances of the United States Controlled Substances Act (US CSA), and similarly controlled globally. The implications of the CSA for research and medicines development, the path to approval of medicines, and their subsequent removal from Schedule I in the US are discussed. This entire process occurs within the framework of the CSA in the US and its counterparts internationally in accordance with international drug control treaties. Abuse potential related research in the US informs the eight factors of the CSA which provide the basis for rescheduling actions that must occur upon approval of a drug that contains a Schedule I substance. Abuse-related research also informs drug product labeling and the risk evaluation and mitigation strategies (REMS) will likely be required for approved medicines. Human abuse potential studies typically employed in CNS drug development may be problematic for substances with strong hallucinogenic effects such as psilocybin, and alternative strategies are discussed. Implications for research, medicinal development, and controlled substance scheduling are presented in the context of the US CSA and FDA requirements with implications for global regulation. We also discuss how abuse-related research can contribute to understanding mechanisms of action and therapeutic effects as well as the totality of the effects of the drugs on the brain, behavior, mood, and the constructs of spirituality and consciousness.

Altered brain activity and functional connectivity after MDMA-assisted therapy for post-traumatic stress disorder.

Introduction: 3,4-methylenedioxymethamphetamine-assisted therapy (MDMA-AT) for post-traumatic stress disorder (PTSD) has demonstrated promise in multiple clinical trials. MDMA is hypothesized to facilitate the therapeutic process, in part, by decreasing fear response during fear memory processing while increasing extinction learning. The acute administration of MDMA in healthy controls modifies recruitment of brain regions involved in the hyperactive fear response in PTSD such as the amygdala, hippocampus, and insula. However, to date there have been no neuroimaging studies aimed at directly elucidating the neural impact of MDMA-AT in PTSD patients. Methods: We analyzed brain activity and connectivity via functional MRI during both rest and autobiographical memory (trauma and neutral) response before and two-months after MDMA-AT in nine veterans and first-responders with chronic PTSD of 6 months or more. Results: We hypothesized that MDMA-AT would increase amygdala-hippocampus resting-state functional connectivity, however we only found evidence of a trend in the left amygdala-left hippocampus (t = -2.91, uncorrected p = 0.0225, corrected p = 0.0901). We also found reduced activation contrast (trauma > neutral) after MDMA-AT in the cuneus. Finally, the amount of recovery from PTSD after MDMA-AT correlated with changes in four functional connections during autobiographical memory recall: the left amygdala-left posterior cingulate cortex (PCC), left amygdala-right PCC, left amygdala-left insula, and left isthmus cingulate-left posterior hippocampus. Discussion: Amygdala-insular functional connectivity is reliably implicated in PTSD and anxiety, and both regions are impacted by MDMA administration. These findings compliment previous research indicating that amygdala, hippocampus, and insula functional connectivity is a potential target of MDMA-AT, and highlights other regions of interest related to memory processes. More research is necessary to determine if these findings are specific to MDMA-AT compared to other types of treatment for PTSD. Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT02102802, identifier NCT02102802.

The catechol-O-methyltransferase inhibitor tolcapone modulates alcohol consumption and impulsive choice in alcohol use disorder.

RATIONALE: Individuals suffering from alcohol use disorder (AUD) demonstrate difficulty with decision-making and impulsivity that may be associated with impaired frontal cortical function. Therapeutics that enhance frontal dopamine tone could decrease impulsivity and in turn reduce alcohol consumption in individuals with AUD. OBJECTIVES: To determine if the catechol-O-methyltransferase (COMT) inhibitor tolcapone can attenuate alcohol consumption in individuals with AUD and whether this attenuation correlates with tolcapone-induced changes in laboratory-based decision-making tasks. METHODS: We used daily self-report and a novel group laboratory bar task to assess the effects of randomized double-blind crossover administration of tolcapone (100 mg TID for 5 days) on alcohol consumption and laboratory tasks assessing impulsivity in 55 non-treatment-seeking subjects with AUD. RESULTS: Tolcapone significantly reduced self-reported alcohol consumption (t (54) = 2.05, p = 0.045). The effects of tolcapone on drinking significantly correlated with changes in impulsive decision-making, such that subjects with the greatest decrease in impulsive choice on tolcapone also reported the greatest decrease in alcohol consumption (r (45) = 0.40, p = 0.0053). We did not see effects of tolcapone on laboratory bar consumption. Adverse event (AE) reporting was low, with no significant difference in frequency or severity of AEs on tolcapone versus placebo. CONCLUSIONS: These data demonstrate that COMT inhibitors such as tolcapone may be useful therapeutics for AUD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02740582.

Intra-VTA deltorphin, but not DPDPE, induces place preference in ethanol-drinking rats: distinct DOR-1 and DOR-2 mechanisms control ethanol consumption and reward.

BACKGROUND: While there is a growing body of evidence that the delta opioid receptor (DOR) modulates ethanol (EtOH) consumption, development of DOR-based medications is limited in part because there are 2 pharmacologically distinct DOR subtypes (DOR-1 and DOR-2) that can have opposing actions on behavior. METHODS: We studied the behavioral influence of the DOR-1-selective agonist [D-Pen(2) ,D-Pen(5) ]-Enkephalin (DPDPE) and the DOR-2-selective agonist deltorphin microinjected into the ventral tegmental area (VTA) on EtOH consumption and conditioned place preference (CPP) and the physiological effects of these 2 DOR agonists on GABAergic synaptic transmission in VTA-containing brain slices from Lewis rats. RESULTS: Neither deltorphin nor DPDPE induced a significant place preference in EtOH-naïve Lewis rats. However, deltorphin (but not DPDPE) induced a significant CPP in EtOH-drinking rats. In contrast to the previous finding that intra-VTA DOR-1 activity inhibits EtOH consumption and that this inhibition correlates with a DPDPE-induced inhibition of GABA release, here we found no effect of DOR-2 activity on EtOH consumption nor was there a correlation between level of drinking and deltorphin-induced change in GABAergic synaptic transmission. CONCLUSIONS: These data indicate that the therapeutic potential of DOR agonists for alcohol abuse is through a selective action at the DOR-1 form of the receptor.

Alcohol self-administration, anxiety, and cortisol levels predict changes in delta opioid receptor function in the ventral tegmental area.

The delta opioid receptor (DOR) agonist DPDPE decreases ethanol (EtOH) consumption when injected into the ventral tegmental area (VTA). We previously showed that DPDPE inhibition of GABAA receptor-mediated inhibitory postsynaptic currents (GABAAR IPSCs) is associated with reduced EtOH consumption. To determine whether self-administration of EtOH is required to change VTA DOR function, we compared the effects of passively administered (gavaged) and self-administered (two-bottle choice) EtOH. Because rats showed variability in DOR regulation of drinking and inhibition of GABAAR IPSCs, we examined whether these changes can be predicted before EtOH exposure by behavioral measures of anxiety or intoxication. Functional DORs were seen with both gavaged and self-administered EtOH, although the magnitude of DPDPE-induced inhibition correlated with behavioral measures only when EtOH was self-administered. Specifically, DPDPE-induced inhibition correlated with predrinking measures of open arm time in the plus maze (n = 19, R = .69, p = .001), with change in maximum fall latency on the rotarod (n = 17, R = .89, p = .000001), and with blood corticosterone (n = 17, R = .66, p = .004) in drinking animals. This DOR-mediated inhibition persisted for at least 14 days after EtOH access was terminated. Together, these findings indicate that anxious animals and those with the greatest EtOH-induced motor impairment have the most robust DPDPE-induced inhibition of GABAAR IPSCs in VTA neurons. These data also extend our understanding of the possible therapeutic value of the DOR for treatment of alcoholism by showing that its relevant synaptic action persists during abstinence.

The anticonvulsant levetiracetam potentiates alcohol consumption in non-treatment seeking alcohol abusers.

BACKGROUND: Levetiracetam (Keppra) is a commonly prescribed anticonvulsant that has been shown to attenuate alcohol consumption in an open-label study of treatment-seeking, alcohol-dependent subjects. METHODS: Here we performed a 42-day placebo-controlled, double-blind, randomized crossover trial to evaluate the effects of levetiracetam on moderate to heavy drinkers receiving either a low (500-1000 g/d) or a moderate (1000-2000 g/d) dose. Electronic diaries were used to monitor daily ethanol intake. RESULTS: Across the entire group, there was no effect of levetiracetam on drinking irrespective of dose, treatment order, family history, ethnicity, sex, or adverse effects. However, a median split of the data based on the number of drinks consumed while taking placebo revealed that levetiracetam significantly increased drinking in the lower drinking subjects (n = 23, P = 0.05, t = 2.07) while having no effect on drinking in the higher half (n = 23, P = 0.75, t = 0.32). Preliminary stratification based on common polymorphisms associated with alcoholism and impulsivity indicated that subjects with alcoholism-associated alleles may drink even more while taking levetiracetam. CONCLUSIONS: Our data suggest that levetiracetam is not an appropriate treatment for non-treatment seeking alcohol abusers and can, in fact, increase their consumption of alcohol.

Reliability in the identification of midbrain dopamine neurons.

Brain regions typically contain intermixed subpopulations of neurons with different connectivity and neurotransmitters. This complicates identification of neuronal phenotypes in electrophysiological experiments without using direct detection of unique molecular markers. A prime example of this difficulty is the identification of dopamine (DA) neurons in the midbrain ventral tegmental area (VTA). Although immunocytochemistry (ICC) against tyrosine hydroxylase (TH) is widely used to identify DA neurons, a high false negative rate for TH ICC following ex vivo electrophysiology experiments was recently reported, calling into question the validity of comparing DA and non-DA VTA neurons based on post-hoc ICC. However, in whole cell recordings from randomly selected rat VTA neurons we have found that TH labeling is consistently detected in ∼55% of neurons even after long recording durations (range: 2.5-150 min). This is consistent with our prior anatomical finding that 55% of VTA neurons are TH(+). To directly estimate a false negative rate for our ICC method we recorded VTA neurons from mice in which EGFP production is driven by the TH promoter. All 12 EGFP(+) neurons recorded with a K-gluconate internal solution (as used in our rat recordings) were strongly labeled by TH ICC (recording duration 16.6±1.8 min). However, using recording electrodes with an internal solution with high Cl(-) concentration reduced the intensity of TH co-labeling, in some cases to background (recording duration 16.7±0.9 min; n = 10). Thus TH is a highly reliable molecular marker for DA neurons in VTA patch clamp recordings provided compatible microelectrode solutions are used.