Medication adherence and symptom reduction in adults treated with mixed amphetamine salts in a randomized crossover study

A Single-Blind, Placebo Controlled Trial of Triple Beaded Mixed Amphetamine Salts in DSM-5 Adults With ADHD Assessing Effects Throughout the Day

OBJECTIVE

To examine the effects of triple beaded mixed amphetamine salts (TB MAS) on ADHD and executive dysfunction symptoms throughout the day in adults with DSM-5 ADHD.

METHOD

This was a 6 week, single-blind, placebo-lead in trial of TB MAS (12.5-37.5 mg/day); all participants received 2 weeks of single-blind placebo); one individual was a placebo responder and was discontinued. One of these 18 dropped after 1 week on 12.5 mg/day, while all others completed the trial and received 37.5 mg/day TB MAS.

RESULTS

There were significant effects of TB MAS on all clinical measures, including investigator overall symptoms (AISRS); self-report overall (ASRS), time-sensitive ADHD (TASS) scores throughout the day, impairment (CGI) and executive function scores (BRIEF-A). TB MAS was generally well tolerated.

CONCLUSIONS

This study extends prior findings of TB MAS to adults with DSM-5 ADHD; it further re-validates findings of efficacy of TB MAS throughout the day.

Triple-Bead Mixed Amphetamine Salts (SHP465) in Adults With ADHD: Results of a Phase 3, Double-Blind, Randomized, Forced-Dose Trial

Objective: Evaluate the efficacy and tolerability of triple-bead mixed amphetamine salts (MAS) in ADHD. Method: Adults with ADHD Rating Scale IV (ADHD-RS-IV) total scores ≥32 were randomized to 6 weeks of triple-bead MAS (25, 50, or 75 mg) or placebo. The primary endpoint was ADHD-RS-IV total score change from baseline at end of study (EOS). Results: Least squares mean (95% confidence interval [CI]) treatment differences for ADHD-RS-IV total score changes from baseline to EOS significantly favored triple-bead MAS (all doses combined: -10.6 [-13.2, -8.0]; p < .0001); there were no significant differences between triple-bead MAS dosages. The most frequently reported TEAEs with triple-bead MAS (all doses combined) included insomnia, decreased appetite, and dry mouth. Mean ± SD pulse and systolic blood pressure increases at EOS were 3.5 ± 10.33 bpm and 0.3 ± 10.48 mmHg with triple-bead MAS (all doses combined). Conclusion: Triple-bead MAS significantly reduced adult ADHD symptoms; the safety profile was consistent with previous triple-bead MAS studies.

Reliability and Validity of the Before-School Functioning Scale in Children With ADHD

OBJECTIVE

Children with ADHD frequently manifest behavioral difficulties in the morning prior to school. We sought to assess the reliability and validity of the Before-School Functioning Questionnaire (BSFQ) as a measure of morning behaviors impaired by ADHD.

METHOD

We used pre-treatment data from a randomized crossover study of 6- to 12-year-old participants comparing the methylphenidate transdermal delivery system (MTS) with a placebo transdermal system (PTS) for a total of 4 weeks.

RESULTS

The BSFQ investigator-rated scale shows very good internal homogeneity (Cronbach's α = .91), good test-retest reliability ( r = .60), good concurrent validity ( r range = .42-.86), and a strong treatment effect (effect size = -.93). The self-rated BSFQ showed lower levels of reliability and validity.

CONCLUSION

The investigator-rated BSFQ should be used in future trials of ADHD medications aimed at assessing efficacy in the morning before school.

Reliability and Validity of the Daily Parent Rating of Evening and Morning Behavior Scale, Revised

OBJECTIVE

Children with ADHD frequently manifest behavioral difficulties in the morning prior to school. We sought to assess the reliability and validity of the Daily Parent Rating of Evening and Morning Behavior Scale, Revised (DPREMB-R) morning score as a measure of morning behaviors impaired by ADHD.

METHOD

We used data from a clinical trial of HLD200 treatment in pediatric participants with ADHD to address our objectives.

RESULTS

The DPREMB-R morning score showed significant internal homogeneity, test-retest reliability ( r = .52-.45), and good concurrent validity ( r = .50-.71).

CONCLUSION

The DPREMB-R morning score could be a useful instrument for assessing treatment efficacy in the morning before school.

Amphetamines for attention deficit hyperactivity disorder (ADHD) in adults

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a childhood-onset disorder characterised by inattention, hyperactivity, and impulsivity. ADHD can persist into adulthood and can affects individuals' social and occupational functioning, as well as their quality of life and health. ADHD is frequently associated with other mental disorders such as substance use disorders and anxiety and affective disorders. Amphetamines are used to treat adults with ADHD, but uncertainties about their efficacy and safety remain.

OBJECTIVES

To examine the efficacy and safety of amphetamines for adults with ADHD.

SEARCH METHODS

In August 2017, we searched CENTRAL, MEDLINE, Embase, PsycINFO, 10 other databases, and two trials registers, and we ran citation searches for included studies. We also contacted the corresponding authors of all included studies, other experts in the field, and the pharmaceutical company, Shire, and we searched the reference lists of retrieved studies and reviews for other published, unpublished, or ongoing studies. For each included study, we performed a citation search in Web of Science to identify any later studies that may have cited it.

SELECTION CRITERIA

We searched for randomised controlled trials comparing the efficacy of amphetamines (at any dose) for ADHD in adults aged 18 years and over against placebo or an active intervention.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data from each included study. We used the standardised mean difference (SMD) and the risk ratio (RR) to assess continuous and dichotomous outcomes, respectively. We conducted a stratified analysis to determine the influence of moderating variables. We assessed trials for risk of bias and drew a funnel plot to investigate the possibility of publication bias. We rated the quality of the evidence using the GRADE approach, which yielded high, moderate, low, or very low quality ratings based on evaluation of within-trial risk of bias, directness of evidence, heterogeneity of data; precision of effect estimates, and risk of publication bias.

MAIN RESULTS

We included 19 studies that investigated three types of amphetamines: dexamphetamine (10.2 mg/d to 21.8 mg/d), lisdexamfetamine (30 mg/d to 70 mg/d), and mixed amphetamine salts (MAS; 12.5 mg/d to 80 mg/d). These studies enrolled 2521 participants; most were middle-aged (35.3 years), Caucasian males (57.2%), with a combined type of ADHD (78.8%). Eighteen studies were conducted in the USA, and one study was conducted in both Canada and the USA. Ten were multi-site studies. All studies were placebo-controlled, and three also included an active comparator: guanfacine, modafinil, or paroxetine. Most studies had short-term follow-up and a mean study length of 5.3 weeks.We found no studies that had low risk of bias in all domains of the Cochrane 'Risk of bias' tool, mainly because amphetamines have powerful subjective effects that may reveal the assigned treatment, but also because we noted attrition bias, and because we could not rule out the possibility of a carry-over effect in studies that used a cross-over design.Sixteen studies were funded by the pharmaceutical industry, one study was publicly funded, and two studies did not report their funding sources.Amphetamines versus placeboSeverity of ADHD symptoms: we found low- to very low-quality evidence suggesting that amphetamines reduced the severity of ADHD symptoms as rated by clinicians (SMD -0.90, 95% confidence interval (CI) -1.04 to -0.75; 13 studies, 2028 participants) and patients (SMD -0.51, 95% CI -0.75 to -0.28; six studies, 120 participants).Retention: overall, we found low-quality evidence suggesting that amphetamines did not improve retention in treatment (risk ratio (RR) 1.06, 95% CI 0.99 to 1.13; 17 studies, 2323 participants).Adverse events: we found that amphetamines were associated with an increased proportion of patients who withdrew because of adverse events (RR 2.69, 95% CI 1.63 to 4.45; 17 studies, 2409 participants).Type of amphetamine: we found differences between amphetamines for the severity of ADHD symptoms as rated by clinicians. Both lisdexamfetamine (SMD -1.06, 95% CI -1.26 to -0.85; seven studies, 896 participants; low-quality evidence) and MAS (SMD -0.80, 95% CI -0.93 to -0.66; five studies, 1083 participants; low-quality evidence) reduced the severity of ADHD symptoms. In contrast, we found no evidence to suggest that dexamphetamine reduced the severity of ADHD symptoms (SMD -0.24, 95% CI -0.80 to 0.32; one study, 49 participants; very low-quality evidence). In addition, all amphetamines were efficacious in reducing the severity of ADHD symptoms as rated by patients (dexamphetamine: SMD -0.77, 95% CI -1.14 to -0.40; two studies, 35 participants; low-quality evidence; lisdexamfetamine: SMD -0.33, 95% CI -0.65 to -0.01; three studies, 67 participants; low-quality evidence; MAS: SMD -0.45, 95% CI -1.02 to 0.12; one study, 18 participants; very low-quality evidence).Dose at study completion: different doses of amphetamines did not appear to be associated with differences in efficacy.Type of drug-release formulation: we investigated immediate- and sustained-release formulations but found no differences between them for any outcome.Amphetamines versus other drugsWe found no evidence that amphetamines improved ADHD symptom severity compared to other drug interventions.

AUTHORS' CONCLUSIONS

Amphetamines improved the severity of ADHD symptoms, as assessed by clinicians or patients, in the short term but did not improve retention to treatment. Amphetamines were associated with higher attrition due to adverse events. The short duration of studies coupled with their restrictive inclusion criteria limits the external validity of these findings. Furthermore, none of the included studies had an overall low risk of bias. Overall, the evidence generated by this review is of low or very low quality.

Beyond the pill: new medication delivery options for ADHD

Successful treatment of pediatric disorders has necessitated the development of alternative medication formulations, as children may prefer alternative dosage forms to tablets or capsules. This is especially true for attention-deficit/hyperactivity disorder (ADHD), which is one of the most common chronic pediatric conditions and often involves children with a variety of overlapping physical, psychological, or neurodevelopmental disorders. A special challenge for developing alternative dosage forms for ADHD treatment is the incorporation of a once-daily long-acting formulation. Traditional ADHD medication formulations have been limited, and issues surrounding prescribed dosing regimens-including poor medication adherence, difficulty swallowing, and the lack of dosing titration options-persist in ADHD treatment. In other disease areas, the development of alternative formulations has provided options for patients who have issues with consuming solid dosage forms, particularly children and individuals with developmental disorders. In the light of these new developments, several alternative formulations for ADHD medications are under development or have recently become available. This article reviews the various strategies for developing alternative dosage forms in other disease areas and discusses the application of these strategies in ADHD treatment. Alternative dosage forms may increase medication adherence, compliance, and patient preference and, therefore, improve the overall treatment for ADHD.

Pharmacokinetic and Pharmacodynamic Properties of Lisdexamfetamine in Adults with Attention-Deficit/Hyperactivity Disorder

BACKGROUND

Lisdexamfetamine (LDX) is a prodrug and consists of an active moiety, d-amphetamine, bound to lysine. Clinically, d-amphetamine becomes available postcleavage of the prodrug in the blood stream. Clinical effects of LDX in attention-deficit/hyperactivity disorder (ADHD) have been shown to persist up to 14 hours; however, pharmacokinetic (PK) data of LDX and amphetamine in ADHD adults are not currently available.

OBJECTIVES

(1) To examine PK data of LDX and d-amphetamine in plasma and (2) to compare such PK data with Time-Sensitive ADHD Symptom Scale (TASS) ratings (PK vs. pharmacodynamic [PD]).

METHODS

Plasma d-amphetamine/LDX levels and TASS ratings were obtained immediately before morning dosing and then 0.5, 1, 2, 4, 6, 8, 10, and 12 hours postdosing in 21 adults with ADHD treated with 5 weeks of single-blind LDX up to 70 mg/day (after 1 week single-blind placebo). ADHD Rating Scale scores were obtained at the beginning of the visit, before morning dosing.

RESULTS

LDX levels peaked at 1.5 hours after administration (T_max) and then rapidly declined (levels were negligible at 6 hours and area under the plasma concentration versus time curve, AUC = 45.9, C_max = 25.0, and half-life [t_1/2] = 0.5 hours). Levels of d-amphetamine peaked at (T_max) 4.4 hours and then slowly declined (AUC = 641.6, C_max = 67.9, and t_1/2 = 17.0 hours). No statistically significant correlations were seen between d-amphetamine levels and TASS scores.

CONCLUSIONS

(1) Prodrug LDX levels peaked fairly rapidly and declined, while d-amphetamine levels peaked 3 hours later than LDX levels and persisted throughout the day and (2) the absence of PK/PD correlations between PK data and TASS ratings may be due to the subjects being tested in a controlled nonattention demanding environment.

Neural Correlates of Symptom Improvement Following Stimulant Treatment in Adults with Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

The purposes of this study were to examine the impact of 3 weeks of amphetamine administration on intrinsic connectome-wide connectivity patterns in adults with attention-deficit/hyperactivity disorder (ADHD) and explore the association between stimulant-induced symptom improvement and functional connectivity alteration.

METHODS

Participants included 19 adults (age 20-55 years) diagnosed with ADHD using the Diagnostic and Statistical Manual of Mental Disorders, 4th ed., Text Revision (DSM-IV-TR) criteria per the Adult Clinician Diagnostic Scale taking part in amphetamine trials. For each patient, two 6-minute resting-state functional magnetic resonance imaging (R-fMRI) scans were acquired at baseline and after treatment. A fully data-driven multivariate analytic approach (i.e., multivariate distance matrix regression [MDMR]) was applied to R-fMRI data to characterize the distributed pharmacological effects in the entire functional connectome. Clinical efficacy was assessed using ADHD rating scale with adult prompts and the Adult Self-Report Scale v1.1 Symptom Checklist. We linked stimulant-induced functional connectivity changes to symptom amelioration using Spearman's correlation.

RESULTS

Three weeks of administration of a stimulant significantly reduced ADHD symptoms. MDMR-based analyses on R-fMRI data highlighted the left dorsolateral prefrontal cortex (DLPFC, a key cognitive control region) and the medial prefrontal cortex (MPFC, the anterior core of default network) whose distributed patterns of functional connectivity across the entire brain were altered by psychostimulants. Follow-up intrinsic functional connectivity revealed that stimulants specifically decreased the positive functional connectivity between DLPFC-insula, DLPFC-anterior cingulate cortex, and MPFC-insula. Importantly, these functional connectivity changes are associated with symptom improvement.

CONCLUSION

These results suggested that ADHD is associated with increased functional integration or decreased functional segregation between core regions of cognitive control, default, and salience networks. The apparent normalization of intrinsic functional interaction in these circuits (i.e., increased functional segregation) may underlie the clinical benefits produced by 3 weeks of amphetamine treatment.

A scoping review of studies comparing the medication event monitoring system (MEMS) with alternative methods for measuring medication adherence

Different methods are available for measuring medication adherence. In this paper, we conducted a scoping review to identify and summarize evidence of all studies comparing the Medication Event Monitoring System (MEMS) with alternative methods for measuring medication adherence. A literature search was performed using the open database www.iAdherence.org that includes all original studies reporting findings from the MEMS. Papers comparing methods for measuring adherence to solid oral formulations were included. Data was extracted using a standardized extraction table. A total of 117 articles fulfilled the inclusion criteria, including 251 comparisons. Most frequent comparisons were against self-report (n = 119) and pill count (n = 59). Similar outcome measures were used in 210 comparisons (84%), among which 78 used dichotomous variables (adherent or not) and 132 used continuous measures (adherence expressed as percentage). Furthermore, 32% of all comparisons did not estimate adherence over the same coverage period and 44% of all comparisons did not use a statistical method or used a suboptimal one. Only eighty-seven (35%) comparisons had similar coverage periods, similar outcome measures and optimal statistical methods. Compared to MEMS, median adherence was grossly overestimated by 17% using self-report, by 8% using pill count and by 6% using rating. In conclusion, among all comparisons of MEMS versus alternative methods for measuring adherence, only a few used adequate comparisons in terms of outcome measures, coverage periods and statistical method. Researchers should therefore use stronger methodological frameworks when comparing measurement methods and be aware that non-electronic measures could lead to overestimation of medication adherence.

Clinical effects of lisdexamfetamine and mixed amphetamine salts immediate release in adult ADHD: results of a crossover design clinical trial

OBJECTIVES

To examine the clinical effects of equivalent doses of single-blind (SB; patient-blind) lisdexamfetamine (LDX) and mixed amphetamine salts-immediate release (MAS-IR) on adult attention-deficit/hyperactivity disorder (ADHD) in a placebo (PBO)-controlled, crossover design.

METHODS

Twenty-four subjects were treated sequentially in a fixed order with (1) SB PBO (matching LDX) for 1 week, (2) SB LDX (up to 70 mg/day) for 5 weeks, (3) SB PBO washout for 3 weeks, and (4) open-label treatment MAS-IR (tid up to 45 mg/day) for 5 weeks. Clinical effects on ADHD and executive function were assessed weekly throughout the trial with the ADHD Rating Scale with adult prompts, the Clinical Global Impression Severity Scale (CGI-S), and the Behavior Rating Inventory of Executive Function (BRIEF).

RESULTS

Lisdexamfetamine and MAS-IR were generally well tolerated. Significant and equal reductions on ADHD clinician ratings were seen. Significantly greater reductions in CGI-S and selected BRIEF subsets were observed in LDX over MAS-IR treatment. However, in general, baseline scores for MAS-IR treatment did not fully return to the LDX baseline. Adherence in this structured and monitored clinical trial was good for once daily LDX and 3 times a day MAS-IR.

CONCLUSIONS

In this crossover study, both LDX and MAS-IR had significant effects on ADHD clinician ratings and measures of executive function (with response rates of about 80%); patients in this monitored clinical trial were adherent with once daily LDX and 3 times a day MAS-IR, which may not be the case in real-world clinical practice. The findings of some superiority of LDX over MAS-IR on the CGI-S and BRIEF ratings may be influenced by the variability in the baselines used, but nevertheless should be further investigated in larger scale, parallel-design clinical trials.

Targeting the nicotinic cholinergic system to treat attention-deficit/hyperactivity disorder: rationale and progress to date

Attention-deficit/hyperactivity disorder (ADHD) is a common chronic neurobehavioral disorder related to clinically significant levels of inattention, hyperactivity, and/or impulsivity. ADHD begins in childhood and symptoms persist into adulthood for the majority of those with the disorder. Associated features of ADHD include emotion dysregulation and cognitive impairments, which contribute to the considerable functional impairments in this disorder. Current approved treatments are reasonably effective; however, a significant need remains for new pharmacotherapies, both for individuals who do not achieve a full therapeutic response and for symptoms that are under-treated including cognition and emotion regulation. The striking relationship between ADHD and cigarette smoking and the known effects of nicotine on cognition has spurred research into the therapeutic potential of nicotinic agents for ADHD. Although there are no approved medications for ADHD that target nicotinic acetylcholine receptor (nAChR) function, results from many trials of nicotinic drugs are available and reviewed in this article. ADHD symptoms were reduced in the majority of published studies of nicotine and novel α4β2 nicotinic agonists in adult ADHD. The drugs were generally well tolerated, with mild to moderate side effects reported, which were largely consistent with cholinergic stimulation and included nausea, dizziness, and gastrointestinal distress. Within-subject crossover study designs were used in the majority of positive studies. This design may be particularly useful in ADHD trials because it minimizes variability in this notoriously heterogeneous diagnostic group. In addition, many studies found evidence for a beneficial effect of nicotinic stimulation on cognitive and emotional domains. Thus, targeting nAChRs in ADHD appears to have a modest clinical benefit in adult ADHD. Continued refinement of nAChR agonists with greater specificity and fewer side effects may lead to even more effective nAChR agonists for ADHD. Future clinical trials in ADHD should include direct measures of neuropsychological performance and emotion regulation.

Identification and assessment of adherence-enhancing interventions in studies assessing medication adherence through electronically compiled drug dosing histories: a systematic literature review and meta-analysis

Background

Non-adherence to medications is prevalent across all medical conditions that include ambulatory pharmacotherapy and is thus a major barrier to achieving the benefits of otherwise effective medicines.

Objective

The objective of this systematic review was to identify and to compare the efficacy of strategies and components thereof that improve implementation of the prescribed drug dosing regimen and maintain long-term persistence, based on quantitative evaluation of effect sizes across the aggregated trials.

Data sources

MEDLINE, EMBASE, CINAHL, the Cochrane Library, and PsycINFO were systematically searched for randomized controlled trials that tested the efficacy of adherence-enhancing strategies with self-administered medications. The searches were limited to papers in the English language and were included from database inception to 31 December 2011.

Study selection

Our review included randomized controlled trials in which adherence was assessed by electronically compiled drug dosing histories. Five thousand four hundred studies were screened. Eligibility assessment was performed independently by two reviewers. A structured data collection sheet was developed to extract data from each study.

Study appraisal and synthesis methods

The adherence-enhancing components were classified in eight categories. Quality of the papers was assessed using the criteria of the Cochrane Handbook for Systematic Reviews of Interventions guidelines to assess potential bias. A combined adherence outcome was derived from the different adherence variables available in the studies by extracting from each paper the available adherence summary variables in a pre-defined order (correct dosing, taking adherence, timing adherence, percentage of adherent patients). To study the association between the adherence-enhancing components and their effect on adherence, a linear meta-regression model, based on mean adherence point estimates, and a meta-analysis were conducted.

Results

Seventy-nine clinical trials published between 1995 and December 2011 were included in the review. Patients randomized to an intervention group had an average combined adherence outcome of 74.3 %, which was 14.1 % higher than in patients randomized to the control group (60.2 %). The linear meta-regression analysis with stepwise variable selection estimated an 8.8 % increase in adherence when the intervention included feedback to the patients of their recent dosing history (EM-feedback) (p < 0.01) and a 5.0 % increase in adherence when the intervention included a cognitive-educational component (p = 0.02). In addition, the effect of interventions on adherence decreased by 1.1 % each month. Sensitivity analysis by selecting only high-quality papers confirmed the robustness of the model. The random effects model in the meta-analysis, conducted on 48 studies, confirmed the above findings and showed that the improvement in adherence was 19.8 % (95 % CI 10.7–28.9 %) among patients receiving EM-feedback, almost double the improvement in adherence for studies that did not include this type of feedback [10.3 % (95 % CI 7.5–13.1 %)] (p < 0.01). The improvement in adherence was 16.1 % (95 % CI 10.7–21.6 %) in studies that tested cognitive-educational components versus 10.1 % (95 % CI 6.6–13.6 %) in studies that did not include this type of intervention (p = 0.04). Among 57 studies measuring clinical outcomes, only 8 reported a significant improvement in clinical outcome.

Limitations

Despite a common measurement, the meta-analysis was limited by the heterogeneity of the pooled data and the different measures of medication adherence. The funnel plot showed a possible publication bias in studies with high variability of the intervention effect.

Conclusions

Notwithstanding the statistical heterogeneity among the studies identified, and potential publication bias, the evidence from our meta-analysis suggests that EM-feedback and cognitive-educational interventions are potentially effective approaches to enhance patient adherence to medications. The limitations of this research highlight the urgent need to define guidelines and study characteristics for research protocols that can guide researchers in designing studies to assess the effects of adherence-enhancing interventions.

Electronic supplementary material

The online version of this article (doi:10.1007/s40265-013-0041-3) contains supplementary material, which is available to authorized users.

An open-label investigation of the pharmacokinetic profiles of lisdexamfetamine dimesylate and venlafaxine extended-release, administered alone and in combination, in healthy adults

Background

Lisdexamfetamine dimesylate (LDX), a prodrug consisting of d-amphetamine and l-lysine, is being studied in clinical trials of major depressive disorder. Additional drug-drug interaction studies were warranted.

Objective

This study aimed to describe the pharmacokinetics and safety of LDX and venlafaxine extended-release (VXR), alone or combined.

Study Design

The study was an open-label, two-arm, single-sequence crossover investigation with randomization to treatment sequence.

Setting and Participants

The study was conducted at two clinical study centres and included healthy adult males and females (18–45 years of age).

Intervention

The study included two single-sequence crossover designs: LDX alone followed by LDX + VXR (Treatment Arm A); and VXR alone followed by VXR + LDX (Treatment Arm B). Drug treatment was initiated on day 1 with once-daily LDX or VXR alone with 15 days’ titration to final dose (LDX 30, 50 and 70 mg for 5 days each; VXR 75, 150 and 225 mg for 5 days each). On days 16–30, VXR, titrated to a final dose of 225 mg, or LDX, titrated to a final dose of 70 mg, was coadministered for participants in Treatment Arm A or B, respectively. On days 31–38, VXR doses were tapered.

Main Outcome Measures

On days 1–2, 15–16 and 30–31, safety evaluations and blood samples were obtained pre-dose through 24 h post-dose for analysis of LDX, d-amphetamine, venlafaxine (VEN), and O-desmethylvenlafaxine (ODV). Combination treatment was considered bioequivalent to single treatment if 90 % confidence intervals (CIs) for geometric mean ratios (GMRs) of analytes fell within the interval 0.80–1.25 based on maximum plasma concentration (C_max) and area under the plasma concentration-time curve (AUC) from time zero to time of last measurable concentration (AUC_τ). Safety assessments included treatment-emergent adverse events (TEAEs), pulse rate and blood pressure (BP), clinical laboratory assessments, and 12-lead electrocardiograms (ECG).

Results

Among 80 enrolled subjects, 77 were included in pharmacokinetic and safety analyses. Combination LDX + VXR was bioequivalent to LDX alone, based on exposure to d-amphetamine (GMR [95 % CI], C_max (ng/mL): 0.97 [0.82, 1.14], AUC_τ: 0.95 [0.81, 1.12]). Exposure to VEN with LDX + VXR (vs. VXR alone) was increased (C_max: 1.10 [0.88, 1.38], AUC_τ: 1.13 [0.88, 1.45]) and ODV decreased (C_max: 0.91 [0.77, 1.06], AUC_τ: 0.83 [0.71, 0.96]), whereas composite VEN + ODV was bioequivalent to VXR alone (C_max: 0.96 [0.84, 1.09], AUC_τ: 0.98 [0.85, 1.13]). TEAEs with LDX or LDX + VXR were similar. Maximum mean increases from baseline were: pulse rate, +8.73 to 12.76 beats/min with either treatment alone and +17.67 to 20.85 beats/min with LDX + VXR; systolic BP, +4.32 to 6.56 mmHg with either treatment alone and +12.96 to 13.78 mmHg with LDX + VXR; diastolic BP, +5.39 to 5.74 mmHg with either treatment alone and +12.09 to 12.46 mmHg with LDX + VXR. One participant was withdrawn due to a serious TEAE (presyncope). No unexpected, clinically meaningful trends or changes from baseline in mean laboratory or ECG parameters were observed during the trial.

Conclusion

In healthy adults, combination LDX + VXR (vs. LDX alone) did not alter exposure to d-amphetamine. Although small changes in exposure to VEN (increased) and ODV (decreased) were seen with combination treatment, total VEN + ODV exposure showed no change (vs. VEN alone). LDX + VXR led to increases in BP and pulse rate, supporting existing recommendations for vital sign monitoring when using these medications.

Pharmacological treatment of adult ADHD

PURPOSE OF REVIEW

This article reviews recent advances in the pharmacological treatment of adult attention deficit hyperactivity disorder (ADHD), focusing on the literature of the last 18 months.

RECENT FINDINGS

Recent works highlight the growing number of treatment options and focus on the effects of pharmacological treatment in special areas of adult ADHD including emotional dysregulation, social functioning or driving performance. Significant clinical improvement was demonstrated in special subgroups, for example, in substance dependent or prison populations with adult ADHD. In our earlier meta-analysis, we estimated the effect size for the pharmacotherapy of adult ADHD in short-term placebo-controlled studies to be in the medium-to-high range (Cohen-d = 0.65). We now replicate these results with the help of most recent studies: stimulants had greater efficacy than nonstimulants.

SUMMARY

Recent studies are consistent with prior reports and indicated that pharmacological treatment of adult ADHD is effective in improving symptoms and other domains, such as social dysfunction, functional impairment and executive functions. Furthermore, we calculated effect sizes from the most recent studies and they are almost identical with prior estimates, and in terms of Cohen-d typically indicate medium-to-high effect sizes for the pharmacotherapy of adult ADHD.