Pimavanserin Exposure-Response Analyses in Patients With Schizophrenia: Results From the Phase 2 ADVANCE Study.

PURPOSE/BACKGROUND: Pimavanserin is a selective serotonin 5-HT 2A receptor inverse agonist/antagonist being investigated in patients with negative symptoms of schizophrenia. This analysis aimed to characterize exposure-response relationships of pimavanserin in this population. METHODS/PROCEDURES: Exposure-response models were developed using data from ADVANCE. Patients with negative symptoms of schizophrenia receiving background antipsychotics were randomized to pimavanserin 20 mg (adjusted to 34 or 10 mg between weeks 2-8 based on efficacy or tolerability) or placebo for 26 weeks. Time-varying pimavanserin exposure measures were predicted for each patient using a population pharmacokinetic model and individual empiric Bayesian parameter estimates. Response measures were the Negative Symptom Assessment 16 (NSA-16, primary end point), Personal and Social Performance scale, negative symptoms component of the Clinical Global Impression of Schizophrenia-Severity Scale, and adverse events. FINDINGS/RESULTS: A higher pimavanserin exposure was associated with greater improvement in NSA-16 score. For a median area under the pimavanserin plasma concentration-time curve from time 0 to 24 hours of 1465 ng × h/mL for the 34-mg dose, the model predicted a 10.5-point reduction in NSA-16 score. This exposure-response relationship with NSA-16 scores was not influenced by covariates. Similar results were observed with Personal and Social Performance and Clinical Global Impression of Schizophrenia-Severity, but not to the extent as NSA-16. There was no significant exposure-response relationship with anxiety, headache, insomnia, or somnolence. IMPLICATIONS/CONCLUSIONS: Increasing pimavanserin plasma concentration was associated with improved NSA-16 scores (primary end point) in patients with negative symptoms of schizophrenia. No exposure-response relationship with select adverse events was observed.

Alterations of immunoglobulin G and immunoglobulin M levels in the breast milk of mothers with exclusive breastfeeding compared to mothers with non-exclusive breastfeeding during 6 months postpartum: The Jordanian cohort study.

OBJECTIVES: The purpose of this study was to measure changes in the concentration of immunoglobulin G (IgG) and immunoglobulin M (IgM) in the mature breast milk of Jordanian mothers during the first 6 months after giving birth between exclusively breastfeeding (EBF) mothers and non-exclusively breastfeeding (non-EBF) mothers. METHODS: A longitudinal follow-up design was used to measure changes in the concentration of IgG and IgM in the mothers' mature milk during the first 6 months after giving birth. Sixty-nine lactating mothers were recruited in this study. Breast milk samples were collected by mothers themselves in the first, fourth, and sixth months of lactation to measure IgG and IgM concentrations using the enzyme-linked immunosorbent assay (ELISA) technique. RESULTS: There was a significant difference in IgG and IgM concentrations between EBF and non-EBF mothers. IgG was higher in the EBF mothers' milk than in the milk of non-EBF mothers, whereas IgM was not affected by the type of baby feeding. CONCLUSION: The concentration of immunoglobulins changes in human breast milk along with breastfeeding intervals. EBF enhances the concentration of IgG in breast milk compared to non-EBF.

Abuse Potential with Oral Route of Administration of a Hydrocodone Extended-Release Tablet Formulated with Abuse-Deterrence Technology in Nondependent, Recreational Opioid Users.

Objective: To compare the oral abuse potential of hydrocodone extended-release (ER) tablet developed with CIMA ® Abuse-Deterrence Technology with that of hydrocodone immediate release (IR). Design: Randomized, double-blind, placebo-controlled, crossover study. Setting and Patients: One study site in the United States; adult nondependent, recreational opioid users. Methods: After confirming their ability to tolerate and discriminate hydrocodone IR 45 mg from placebo, eligible participants were randomized to receive each of the following oral treatments once: finely crushed placebo, hydrocodone IR 45-mg powder, intact hydrocodone ER 45-mg tablet, and finely crushed hydrocodone ER 45-mg tablet. Primary pharmacodynamic measure was "at the moment" drug liking. Secondary measures included overall drug liking, drug effects (e.g., balance, positive, negative, sedative), pupillometry, pharmacokinetics, and safety. Results: Mean maximum effect (E max ) for "at the moment" drug liking was significantly lower for intact (53.9) and finely crushed hydrocodone ER (66.9) vs. hydrocodone IR (85.2; P < 0.001). Drug liking for intact hydrocodone ER was comparable to placebo (E max : 53.9 vs. 53.2). Secondary measures were consistent with these results, indicating that positive, negative, and sedative drug effects were diminished with intact and crushed hydrocodone ER tablet vs. hydrocodone IR. The 72-hour plasma concentration-time profile for each treatment mimicked its respective "at the moment" drug-liking-over-time profile. Incidence of adverse events was lower with intact hydrocodone ER (53%) vs. hydrocodone IR (79%) and finely crushed hydrocodone ER (73%). Conclusions: The oral abuse potential of hydrocodone ER (intact and finely crushed) was significantly lower than hydrocodone IR in healthy, nondependent, recreational opioid users. Hydrocodone ER was generally well tolerated.

Characterization of the Pharmacokinetics and Mass Balance of a Single Oral Dose of Trofinetide in Healthy Male Subjects.

BACKGROUND AND OBJECTIVE: Trofinetide is the first drug to be approved for the treatment of Rett syndrome, a neurodevelopmental disorder. The purpose of the study is to fully characterize the metabolic and excretion profiles of trofinetide in humans. METHODS: This Phase 1, open-label, single-dose trial conducted in healthy male adults was designed to characterize the pharmacokinetics of trofinetide (absorption, metabolism, and excretion), mass balance of [14C]-trofinetide, and safety profile of trofinetide following administration of an oral 12-g dose administered as a mixture of trofinetide and [14C]-trofinetide. Blood, urine, and fecal samples were collected at prespecified timepoints. The pharmacokinetics of trofinetide were assessed in blood and urine samples using high-performance liquid chromatography (HPLC) with tandem mass spectrometric detection. Bioanalysis of radioactivity was conducted in blood, plasma, urine, and fecal samples using liquid scintillation counting. Metabolite profiling was conducted in blood, plasma, urine, and fecal samples using HPLC with liquid scintillation counting of chromatographic fractions. Safety and tolerability, including treatment-emergent adverse events (TEAEs), were assessed. RESULTS: Blood concentration-time profiles of trofinetide and total radioactivity were almost superimposable up to ~12 h after dosing. Urine concentration-time profiles of trofinetide and total radioactivity were similar. Trofinetide was rapidly absorbed into the circulation with an initial rapid decline (half-life [t½] alpha ~2.6 h), followed by a relatively slow terminal elimination phase (t½ beta ~20 h). The blood-to-plasma total radioactivity ratios were 0.529-0.592, indicating a lack of affinity for the cellular portion of blood. Renal excretion accounted for 83.8% of the administered radiochemical dose; 15.1% was recovered in feces. Urine and fecal recovery of radioactivity accounted for 99% of the administered dose at 168 h after dosing. Parent [14C]-trofinetide was the major radiolabeled entity in blood and plasma (88.4% and 93.1% in area under the concentration-time curves from 0 to 12 h [AUC0-12] in pooled blood and plasma samples, respectively) and the major entity excreted in urine (91.5% in 0-48-h pooled urine samples) and in feces (52.7% in 0-192-h pooled fecal samples). Only small levels of metabolites were present. In blood and plasma, only two minor metabolites were identified (each metabolite ≤ 2.24% of the AUC0-12 pool). These two metabolites were also observed in urine and fecal samples (≤ 2.41% of dose). In feces, one additional metabolite (0.84% of dose) was identified. Two mild TEAEs were reported in two participants and were not considered related to trofinetide. There were no clinically meaningful changes in individual laboratory parameters, vital signs, physical findings, or electrocardiogram results. CONCLUSIONS: Metabolic and excretion profiles confirm that trofinetide undergoes minimal hepatic or intestinal metabolism and is primarily excreted unchanged in the urine. Trofinetide containing radiolabeled [14C]-trofinetide was well tolerated.

Trofinetide is the first approved treatment for Rett syndrome, a rare genetic condition that affects brain development. Study aims were to look at how a single oral dose of trofinetide is absorbed into the bloodstream, to see whether trofinetide's chemical structure is changed once in the body, and to see how trofinetide and any metabolites (chemically altered trofinetide) are removed from the body. Safety and tolerability of trofinetide were also assessed. Eight healthy adult men took a single oral 12-g dose administered as a mixture of ¹⁴C-radiolabeled and nonlabeled trofinetide. Researchers collected blood, urine, and stool samples at regular intervals for up to 10 days postdose to measure levels of trofinetide and its metabolites. Trofinetide was rapidly absorbed (time to maximum concentration was 2 h postdose) and was primarily present in the blood as the unaltered compound. Concentrations decreased rapidly during the first 24 h postdose and more slowly thereafter. Most of the dose was recovered in urine with a lower amount in stool samples (83.8% and 15.1% of the radiochemical dose, respectively). Total recovery in urine and stool samples was 99%, primarily as the chemically unaltered compound. Only low levels of three trofinetide metabolites were detected. Two metabolites were found in blood, urine, and stool samples, while one metabolite was found in stool samples only. Two mild treatment-emergent adverse events, considered to be unrelated to trofinetide, were reported. In summary, trofinetide is rapidly absorbed, minimally metabolized, and mainly removed from the body in the urine as the unchanged drug.

Exposure-Response Efficacy Modeling to Support Trofinetide Dosing in Individuals with Rett Syndrome.

INTRODUCTION: Trofinetide was recently approved for the treatment of Rett syndrome (RTT) on the basis of the efficacy and safety findings of the phase 3 LAVENDER study, which used a body weight-based dosing regimen. Exposure-response (E-R) efficacy modeling was used to characterize relationships between trofinetide exposure measures (maximum drug concentration and area under the concentration-time curve for the dosing interval of 0-12 h [AUC0-12]) and efficacy endpoints in RTT clinical studies to support the trofinetide dosing regimen. METHODS: Efficacy endpoints were modeled using trofinetide exposure measures predicted from the population pharmacokinetic model and Bayesian estimates. The analysis population for each E-R model comprised individuals receiving placebo or trofinetide who had available trofinetide exposure measures. Efficacy endpoints were scores from the Rett Syndrome Behaviour Questionnaire (RSBQ), the Clinical Global Impression-Improvement, the Communication and Symbolic Behavior Scales Developmental Profile™ Infant-Toddler Checklist (CSBS-DP-IT) Social Composite, and the Rett Syndrome Clinician Rating of Ability to Communicate Choices (RTT-COMC). RESULTS: Higher trofinetide exposure was associated with improvements in RSBQ, CSBS-DP-IT Social Composite, and RTT-COMC scores. Assuming target trofinetide AUC0-12 values of 800-1200 µg·h/mL, the reductions in RSBQ total scores at week 12 were approximately five- to seven-fold greater with trofinetide (range 3.55-4.94) versus placebo (0.76). Significant E-R relationships were also found for the CSBS-DP-IT Social Composite and RTT-COMC scores. CONCLUSION: E-R efficacy modeling demonstrated significant relationships between trofinetide exposure and RSBQ, CSBS-DP-IT Social Composite, and RTT-COMC scores. Trofinetide is efficacious within the target exposure range, supporting the approved dosing regimen for trofinetide. TRIAL REGISTRATION: NCT01703533, NCT02715115, NCT04181723.

Trofinetide is the first approved treatment for people living with Rett syndrome, a rare genetic condition affecting brain development. This approval was based on the findings of clinical studies in which trofinetide showed significant improvements in the symptoms of Rett syndrome. In this study researchers were looking to see if the level of trofinetide in the blood was related to the level of improvement in symptoms observed in clinical studies. Information on the effectiveness of trofinetide was obtained from the phase 3 LAVENDER study which used doses of trofinetide according to body weight. Trofinetide's effectiveness was assessed on the basis of clinical measurements of key Rett syndrome symptoms. All the information on trofinetide dose, blood levels, and how much symptoms changed (i.e., effectiveness of trofinetide) was then used to develop models to predict symptom responses in the observed population. Researchers found that as the blood levels of trofinetide increased the symptom improvement also increased. When the blood levels were at the recommended level that was achieved in the LAVENDER study, the model predicted that symptom improvement was up to seven times greater with trofinetide than having no treatment (i.e., placebo). This study shows a positive relationship between trofinetide blood levels and improvement in the symptoms of Rett syndrome. Trofinetide was effective within the recommended blood level range in the LAVENDER study using the approved weight-based dosing.

Effect of Hepatic Impairment on Trofinetide Exposures Using an In Silico Physiologically Based Pharmacokinetic Model.

INTRODUCTION: Trofinetide is the first drug to be approved for the treatment of Rett syndrome. Hepatic impairment is not expected to affect the pharmacokinetic (PK) profile of trofinetide because of predominant renal excretion. This study was conducted to help understand the potential impact of any hepatic impairment on trofinetide PK. METHODS: This study used physiologically based PK modeling to estimate trofinetide exposure (maximum drug concentration and area under the concentration-time curve from time zero to infinity) in virtual patients with mild, moderate, and severe hepatic impairment (per Child-Pugh classification) compared with virtual healthy subjects following a 12 g oral trofinetide dose. RESULTS: In individual deterministic simulations for matched individuals and stochastic simulations at the population level (100 virtual individuals simulated per population), as anticipated, predicted plasma exposures were similar for healthy subjects and for patients with mild, moderate, and severe hepatic impairment. However, predicted blood concentration exposures slightly increased with increasing severity of hepatic impairment because of change in hematocrit levels. CONCLUSION: This study indicates that hepatic impairment is not expected to have a clinically relevant effect on exposure to trofinetide.

Trofinetide is the first approved treatment for Rett syndrome, a rare genetic condition that affects brain development. When a person takes trofinetide, most is removed from the body via the urine in its unchanged form (no chemical alteration). Regulatory requirements mean researchers must confirm the safety of any pharmaceutical drug and evaluate whether changes in liver function lead to harmful levels of drug exposure. Researchers used a computer model to predict how much trofinetide would be present in the blood and plasma (the liquid portion of blood) over time in virtual healthy subjects and virtual patients with varying degrees of liver disease (mild, moderate, or severe). Computer simulations showed that predicted trofinetide levels in plasma were similar in virtual healthy subjects and each virtual patient group with liver disease. Predicted levels of trofinetide in blood were slightly elevated with increasing severity of liver disease. This is because people with liver disease have fewer red blood cells, so the cell portion of blood becomes smaller relative to the liquid portion (plasma), which leads to higher trofinetide concentrations in whole blood (trofinetide minimally enters the red blood cell). The small increase in trofinetide levels in blood and the absence of any change in trofinetide levels in plasma means that people with Rett syndrome and liver disease are unlikely to be exposed to harmful levels of trofinetide after a 12 g oral dose.

Adherence to Background Antipsychotic and Pimavanserin in Patients with Schizophrenia: Post Hoc Analyses from the ENHANCE and ADVANCE Studies.

Background: In patients with schizophrenia, study design to optimize adherence and objective measurement of adherence is critical for interpreting results. Two randomized, double-blind studies evaluating adjunctive pimavanserin in patients with schizophrenia who received stable antipsychotic treatment included measures to encourage and assess treatment adherence. Objective: This post hoc analysis evaluated adherence levels achieved in the Phase III ENHANCE study (NCT02970292) and the Phase II ADVANCE study (NCT02970305). Methods: Blood levels of participants receiving adjunctive treatment with pimavanserin or placebo added to their ongoing antipsychotic medication were tested and evaluated regularly throughout both studies. For both the background antipsychotic and pimavanserin, treatment adherence was defined as a blood sample test result above the lower limit of quantification. Results: Overall, 392 of 633 screened patients and 403 of 608 screened patients were in the safety populations in ENHANCE and ADVANCE, respectively. In ENHANCE, at weeks 1, 3, and 6/early termination (ET), the adherence rates remained ≥ 95.1% for the background antipsychotic in both pimavanserin and placebo treatment groups and ≥ 96.8% for pimavanserin. In ADVANCE, high adherence rates (≥90.6%) with the background antipsychotic (for both treatment groups) and pimavanserin (≥95.0%) were observed at weeks 2, 8, 14, and 26/ET. Conclusion: Rigorous screening was performed to exclude patients not adherent to their background antipsychotic before enrollment and to pimavanserin during study visits by using regular blood sampling. Mandatory caregiver participation further supported adherence to study treatment and procedures. These efforts may have contributed to the high levels of adherence to both background antipsychotic and pimavanserin reported in ENHANCE and ADVANCE.

A Physiologically Based Pharmacokinetic Modeling Approach to Assess the Potential for Drug Interactions Between Trofinetide and CYP3A4-Metabolized Drugs.

PURPOSE: Trofinetide is the first drug to be approved by the US Food and Drug Administration for use in the treatment of patients with Rett syndrome, a multisystem disorder requiring multimodal therapies. Cytochrome P450 (CYP) 3A4 metabolizes >50% of therapeutic drugs and is the CYP isozyme most commonly expressed in the liver and intestines. In vitro studies suggest the concentration of trofinetide producing 50% inhibition (IC50) of CYP3A4 is >15 mmol/L; that concentration was much greater than the target clinical concentration associated with the maximal intended therapeutic dose (12 g). Thus, trofinetide has a low potential for drug-drug interactions in the liver. However, there is potential for drug-drug interactions in the intestines given the oral route of administration and expected relatively high concentration in the gastrointestinal tract after dose administration. METHODS: Using a validated physiologically based pharmacokinetic (PBPK) model, deterministic and stochastic simulations were used for assessing the PK properties related to exposure and bioavailability of midazolam (sensitive index substrate for CYP3A4) following an oral (15 mg) or intravenous (2 mg) dose, with and without single-dose and steady-state (12 g) coadministration of oral trofinetide. FINDINGS: Following coadministration of intravenous midazolam and oral trofinetide, the PK properties of midazolam were unchanged. The trofinetide concentration in the gut wall was >15 mmol/L during the first 1.5 hours after dosing. With the coadministration of oral midazolam and trofinetide, the model predicted increases in fraction of dose reaching the portal vein, bioavailability, Cmax, and AUCinf of 30%, 30%, 18%, and 30%, respectively. IMPLICATIONS: In this study that used a PBPK modeling approach, it was shown that CYP3A4 enzyme activity in the liver was not affected by trofinetide coadministration, but trofinetide was predicted to be a weak inhibitor of intestinal CYP3A4 metabolism after oral administration at therapeutic doses.

Population Pharmacokinetic Modeling and Stochastic Simulations to Support Pediatric Dose Selection of Pimavanserin.

Pimavanserin is a selective serotonin-modulating agent with inverse agonist/antagonist activity at the 5-hydroxytryptamine2A (5-HT2A ) receptor. The safety and efficacy of pimavanserin 34 mg once daily were studied in adults with hallucinations and delusions associated with Parkinson's disease psychosis and other neuropsychiatric conditions. This analysis used model-based simulations of pimavanserin steady-state exposures to identify a dose that generated pediatric exposures comparable with adult exposures achieved with 34 mg pimavanserin. A population pharmacokinetics model was developed using pooled plasma drug concentration (ie, actual) data from 13 clinical studies, including a phase 1 study of adolescent pediatric patients (aged 13-17 years) with various psychiatric conditions. Stochastic simulations were performed to predict exposures in a virtual (ie, simulated) group of pediatric patients (aged 5-17 years). Steady-state measures of the area under the plasma concentration-time curve (AUC) and maximum drug concentration (Cmax ) were simulated for relevant age and weight stratifications and compared with simulated exposures in adults (aged 18-49 years). The simulated mean AUC ranged from 47.41 to 54.73 ng d/mL and the mean Cmax ranged from 41.13 to 50.07 ng/mL in adults receiving pimavanserin 34 mg. The simulated mean (SD) Cmax of 56.54 (24.58) ng/mL with pimavanserin 34 mg in patients aged 10-17 years was similar to that in adults. Pimavanserin 20 mg yielded a mean (SD) Cmax of 45.30 (21.31) ng/mL in patients aged 5-9 years and 49.18 (22.91) ng/mL in the pediatric patient weight group of 14-25 kg, which are values close to the Cmax in adults treated with 34 mg. Pimavanserin 20 and 34 mg in pediatric patients aged 5-9 and 10-17 years, respectively, yielded exposures similar to daily pimavanserin 34 mg in adults aged 18-49 years.

Exposure-response Modeling From the CLARITY Trial of Pimavanserin for Adjunctive Treatment of Major Depressive Disorder.

In the 10-week, phase 2 CLARITY study of patients with major depressive disorder, adjunctive therapy to antidepressants with pimavanserin 34 mg once daily statistically significantly improved the Hamilton Depression Rating Scale (HAMD-17) total score (primary endpoint) and Sheehan Disability Scale (SDS) score (secondary endpoint) versus placebo. This analysis characterized the exposure-response (E-R) relationships of pimavanserin in this CLARITY patient population. Exposure measures were estimated for each patient based on population-pharmacokinetic empirical Bayesian estimates. E-R models were developed to describe exposure-efficacy (HAMD-17, SDS, and Clinical Global Impression-Improvement [CGI-I] scale) and exposure-safety relationships (Karolinska Sleepiness Scale [KSS], Massachusetts General Hospital Sexual Functioning Inventory [MGH-SFI], and adverse events [AEs] of headache, sedation, and somnolence) relationships. For the primary efficacy endpoint (HAMD-17 scores), a sigmoid maximum-effect model described the time course of response, and a linear function of pimavanserin exposure was statistically significant. HAMD-17 scores decreased steadily over time following placebo and pimavanserin treatment; separation from placebo increased as peak pimavanserin plasma concentration (Cmax ) increased. At median pimavanserin Cmax (34-mg dose), the reduction from baseline in HAMD-17 scores was -11.1 and -13.5 at weeks 5 and 10, respectively. Relative to placebo, the model predicted comparable reductions in HAMD-17 scores at weeks 5 and 10. Similar improvements in favor of pimavanserin were detected with SDS, CGI-I, MGH-SFI, and KSS scores. No E-R relationship was found for AEs. E-R modeling predicted a relationship between higher pimavanserin exposure and improvement in HAMD-17 score and improvement across multiple secondary efficacy endpoints.

Metabolite profiling of bendamustine in urine of cancer patients after administration of [14C]bendamustine.

Bendamustine is an alkylating agent consisting of a mechlorethamine derivative, a benzimidazole group, and a butyric acid substituent. A human mass balance study showed that bendamustine is extensively metabolized and subsequently excreted in urine. However, limited information is available on the metabolite profile of bendamustine in human urine. The objective of this study was to elucidate the metabolic pathways of bendamustine in humans by identification of its metabolites excreted in urine. Human urine samples were collected up to 168 h after an intravenous infusion of 120 mg/m(2) (80-95 µCi) [(14)C]bendamustine. Metabolites of [(14)C]bendamustine were identified using liquid chromatography (high-resolution)-tandem mass spectrometry with off-line radioactivity detection. Bendamustine and a total of 25 bendamustine-related compounds were detected. Observed metabolic conversions at the benzimidazole and butyric acid moiety were N-demethylation and γ-hydroxylation. In addition, various other combinations of these conversions with modifications at the mechlorethamine moiety were observed, including hydrolysis (the primary metabolic pathway), cysteine conjugation, and subsequent biotransformation to mercapturic acid and thiol derivatives, N-dealkylation, oxidation, and conjugation with phosphate, creatinine, and uric acid. Bendamustine-derived products containing phosphate, creatinine, and uric acid conjugates were also detected in control urine incubated with bendamustine. Metabolites that were excreted up to 168 h after the infusion included products of dihydrolysis and cysteine conjugation of bendamustine and γ-hydroxybendamustine. The range of metabolic reactions is generally consistent with those reported for rat urine and bile, suggesting that the overall processes involved in metabolic elimination are qualitatively the same in rats and humans.

Pharmacokinetics of fentanyl buccal tablet: a pooled analysis and review.

Fentanyl buccal tablet (FBT) is indicated for the treatment of breakthrough pain in patients who are already receiving and are tolerant to opioid therapy for underlying, persistent cancer pain. FBT is designed to enhance the rate and efficiency of absorption of fentanyl through the buccal mucosa. FBT was shown to be dose proportional from 100 to 1,300 µg. This analysis provides an overview of the pharmacokinetic profile of FBT based on pooled data from nine pharmacokinetic studies. In all, 365 healthy non-opioid-tolerant adults receiving naltrexone were included in the analysis. Single-dose (100 to 1,300 µg) pharmacokinetic parameters were dose normalized to 100 µg. Pharmacokinetic measures included maximum observed plasma drug concentration (C(max)), plasma drug concentration versus time curve from time zero to infinity (AUC(0-∞)), time to reach C(max) (T(max)), apparent plasma terminal elimination rate constant, and elimination half-life. After FBT administration, fentanyl was rapidly absorbed, with T(max) ranging from 20 minutes to 4 hours postdose. Mean AUC(0-∞) was 1.49 ng•hour/mL, and mean C(max) was 0.237 ng/mL. However, plasma fentanyl concentration reached 80% of C(max) within 25 minutes and was maintained through 2 hours after administration. Based on the individual studies, bioequivalence was shown for sublingual and buccal tablet placement, and no significant effect of dwell time (duration of FBT presence in the oral cavity) was observed. The pharmacokinetic profile of FBT was characterized by rapid absorption, which is consistent with the rapid-onset efficacy profile of FBT observed in clinical studies.

A Phase 1, Open-Label Study to Evaluate the Effects of Food and Evening Dosing on the Pharmacokinetics of Oral Trofinetide in Healthy Adult Subjects.

BACKGROUND AND OBJECTIVE: Trofinetide, a synthetic analog of tripeptide glycine-proline-glutamate, is an investigational agent for the treatment of Rett syndrome, a neurodevelopmental disorder with affected individuals requiring lifelong support. Food can affect the pharmacokinetic profile of a drug, and this phase 1 study assessed the potential effect of food on the pharmacokinetics of trofinetide. The study also evaluated the potential effect of evening dosing on trofinetide bioavailability and characterized the pharmacokinetic profile of trofinetide in urine. METHODS: A 60 mL oral solution of trofinetide (12 g) was administered in three dosing periods: morning fasted (A; reference), morning fed (B), and evening fasted (C). Healthy adult subjects (18-45 years) were randomized to sequence ABC (n = 19) or BAC (n = 22). Blood and urine samples were collected at scheduled timepoints for trofinetide pharmacokinetic analysis. Bioequivalence was confirmed if 90% confidence intervals for geometric mean ratio between B/A or C/A fell within 80-125% equivalence limits for area under the concentration-time curve (AUC) and maximum concentration (Cmax) in whole blood. RESULTS: Bioequivalence criteria were met for all conditions (i.e., morning fed vs. morning fasted and evening fasted vs. morning fasted) except Cmax in the fed versus fasted condition, which was just below the bioequivalence limit (75.49%), suggesting a negligible food effect and lack of diurnal variation on bioavailability. Trofinetide was primarily excreted unchanged in urine. Trofinetide was well tolerated, and there were no significant changes in vital signs or laboratory parameters. CONCLUSION: This study supports dosing of trofinetide without regard to food.

Efficacy and safety of active vitamin D supplementation in chronic spontaneous urticaria patients.

BACKGROUND: Chronic spontaneous urticaria (CSU) is a common skin disorder affecting negatively patients' lives. Vitamin D deficiency has been reported to be associated to many allergic skin disorders. OBJECTIVE: This study aimed to evaluate the association between the serum level of 25 hydroxy vitamin D and CSU and to assess the efficacy and safety of active vitamin D in management of CSU. METHODS: The study was conducted on 77 patients with CSU and 67 healthy controls, then the 77 CSU patients were randomized to either the study group that received 0.25 µg alfacalcidol daily or the placebo group that received oral placebo for 12 weeks. RESULTS: Serum 25(OH) D was significantly lower in CSU as compared to healthy controls and was negatively correlated to the urticarial severity. After alfacalcidol administration, the study group showed significant higher level of 25(OH) D compared to the placebo group. In addition, the mean serum level of IL6, hsCRP and TNFα significantly decreased in the study group in comparison to the placebo group and as compared to their baseline results. CONCLUSION: Vitamin D deficiency is more common in CSU patients as compared to healthy people and hence, alfacalcidol might have a beneficial role as add on therapy in CSU management with no reported side effects.

Dose proportionality of fentanyl buccal tablet in doses ranging from 600 to 1300 microg in healthy adult subjects: a randomized, open-label, four-period, crossover, single-centre study.

Fentanyl buccal tablet (FBT) is indicated for the treatment of breakthrough pain in patients who are already receiving, and who are tolerant to, opioid therapy for underlying, persistent cancer pain. Breakthrough pain may be severe or excruciating, and some patients may require high doses of rapid-onset opioids to obtain adequate analgesia. The objective of this study was to assess the dose proportionality of FBT over a range of 600-1300 microg in healthy subjects. This was a randomized, open-label, four-period, crossover, single-centre study of FBT (Fentora) conducted in healthy adult subjects who were not tolerant to opioids. The study included 120 men and women aged 18-45 years with a body mass index of 20-30 kg/m2 who had no clinically significant findings on medical and psychiatric histories, physical examination, ECG or standard clinical laboratory tests, and who had a negative urine screen for drugs and alcohol. Eligible subjects were randomized to one of four dose sequences: ABDC, BCAD, CDBA and DACB, where A, B, C and D were FBT doses from lowest to highest (600, 1000, 1200 and 1300 microg). Each dose of FBT was separated by a minimum of 7 days. Naltrexone 50 mg was administered to block the opioid receptor-mediated effects of fentanyl. Plasma fentanyl concentration was measured through 72 hours after placement of FBT. The main outcome measures, maximum plasma fentanyl concentration (C(max)) and area under the plasma drug concentration versus time curve from time zero to infinity (AUC(infinity)), were analysed to determine dose proportionality. Other pharmacokinetic parameters were also evaluated. Dose proportionality was concluded if the two-sided 90% confidence intervals (CIs) for the slopes of the C(max) versus dose and AUC(infinity) versus dose curves were completely contained within the range of 0.711-1.289. The safety and tolerability of FBT were assessed throughout the study. The slope for C(max) versus dose was 0.8627 (90% CI 0.7730, 0.9525), and the slope for AUC(infinity) versus dose was 0.9330 (90% CI 0.8738, 0.9922). Given that the CIs for C(max) and AUC(infinity) were within the predefined range of 0.711-1.289, dose proportionality was concluded over the 600-1300 microg range. The mean dose-normalized plasma fentanyl concentration reached 80% of C(max) within 25 minutes; plasma fentanyl concentration was maintained at this level for 3 hours after dose. No unexpected safety or tolerability concerns were noted in the naltrexone-blocked healthy subjects. Seventy-four subjects (68%) experienced adverse events (AEs); all were mild (56 [51%]) or moderate (18 [17%]). The most common AEs were nausea, dizziness and headache. No serious AEs were reported. The dose proportionality of FBT from 600-1300 microg was shown in healthy subjects. Based on the data, when FBT is titrated up to 1300 microg, a predictable and linear increase in systemic exposure can be expected. Currently, FBT is approved up to 800 microg. This study provides pharmacokinetic data to support a potential, expanded therapeutic dose range of FBT.

A pharmacokinetic comparison of single doses of once-daily cyclobenzaprine extended-release 15 mg and 30 mg: a randomized, double-blind, two-period crossover study in healthy volunteers.

OBJECTIVE: The purpose of this study was to compare the pharmacokinetics and tolerability of single oral doses of cyclobenzaprine extended-release (CER) 15- and 30-mg capsules. METHODS: This was a randomized, double-blind, 2-period crossover study in healthy adults aged 18 to 40 years. Subjects were assigned to receive a single dose of either CER 15 mg or 30 mg on days 1 and 15, separated by a 14-day washout. Study comparisons included the plasma cyclobenzaprine AUC to 168 hours after dosing (AUC(0-168)), AUC(0-infinity), and C(max). Plasma cyclobenzaprine T(max), terminal elimination t(1/2), and adverse events (AEs) were also assessed. RESULTS: Sixteen subjects (9 women, 7 men) were randomized to receive cyclobenzaprine 15 mg or 30 mg; 13 (81.3%) were white and 3 (18.8%) were black. Mean age and weight were 30.2 years and 70.7 kg, respectively. The shapes of the pharmacokinetic profiles for CER 15 and 30 mg were parallel. Mean observed values for dose-dependent pharmacokinetic parameters of CER 15 and 30 mg were as follows: AUC(0-168), 318.3 and 736.6 ng . h/mL, respectively; AUC(0-infinity)), 354.1 and 779.9 ng . h/mL; and C(max), 8.3 and 19.9 ng/mL. Dose-independent parameters were comparable across doses. Median observed Tmax was 6.0 hours for both CER doses; mean t(1/2) was 33.4 hours for CER 15 mg and 32.0 hours for CER 30 mg. The bioavailability of the 2 doses, as indicated by the least squares mean AUC(0-infinity), was 330.3 ng . h/mL for CER 15 mg and 755.1 ng . h/mL for CER 30 mg. During the CER 15-mg treatment sequence, 5 subjects experienced 5 AEs (headache, dizziness, musculoskeletal pain, dermatitis, and glossodynia); during the CER 30-mg treatment sequence, 2 subjects experienced 2 AEs (somnolence and dysmenorrhea). All AEs were mild in intensity. No serious AEs occurred during the study. CONCLUSIONS: Once-daily CER 15 and 30 mg exhibited similarly shaped pharmacokinetic profiles. AUC(0-168), AUC(0-infinity)), and C(max) values for the 30-mg dose were approximately double those for the 15-mg dose, a result consistent with previously reported data on the dose proportionality of cyclobenzaprine immediate release.

Comparison of the single-dose pharmacokinetics of once-daily cyclobenzaprine extended-release 30 mg and cyclobenzaprine immediate-release 10 mg three times daily in the elderly: a randomized, open-label, crossover study.

BACKGROUND AND OBJECTIVE: The clinical utility of cyclobenzaprine for the treatment of muscle spasm associated with acute, painful musculoskeletal conditions is limited by cholinergic adverse effects associated with its use. As expected, these effects may be pronounced in the elderly in whom altered renal and hepatic function may change drug pharmacokinetics. The goal of this study was to characterize the pharmacokinetics of the extended-release formulation of cyclobenzaprine (CER) in elderly volunteers. METHODS: This randomized, open-label, two-period crossover study compared the pharmacokinetics, safety and tolerability of a single oral 30-mg dose of CER with those of 10 mg of cyclobenzaprine immediate-release (CIR) administered every 8 hours for a total of three doses in 18 healthy volunteers aged 65-75 years. Volunteers were assigned to either CER or CIR on days 1 and 15 (separated by a 14-day washout). Outcome measures included area under the plasma cyclobenzaprine concentration versus time curve (AUC) to 168 hours (AUC168) and infinity (AUC infinity), peak plasma cyclobenzaprine concentration (Cmax), time to observed Cmax (tmax) and terminal elimination half-life of cyclobenzaprine. Adverse events (AEs) were monitored during the study through 3 weeks after the last dose of study drug. RESULTS: Eighteen subjects were randomized and completed the first treatment period; 17 completed both periods of the study. The pharmacokinetics of CER 30 mg were characterized by an absorption phase with a median t(max) of 8 hours compared with an initial peak for CIR (following the first dose) at about 5 hours. Plasma cyclobenzaprine concentrations at 5 hours were 13.6 ng/mL for CER and 11.0 ng/mL for CIR. Systemic cyclobenzaprine exposure (AUC168, AUC infinity and Cmax) was similar for a single dose of CER and three doses of CIR and met bioequivalence criteria. Most AEs were mild in intensity; the most common AE was somnolence. No serious AEs or discontinuations as a result of AEs were reported during the study. CONCLUSION: Once-daily CER 30 mg exhibited controlled release of cyclobenzaprine and resulted in systemic exposure similar to that of CIR in subjects aged 65-75 years.

Effect of food on the pharmacokinetics of once-daily cyclobenzaprine extended-release 30 mg: a randomized, open-label, crossover, single-centre study.

BACKGROUND AND OBJECTIVE: Food can alter the bioavailability of the controlled-release formulations of many different drugs. This study assessed the effect of food on the pharmacokinetics of once-daily cyclobenzaprine extended-release (CER) in healthy adult subjects. METHODS: Healthy adult volunteers were randomized in an open-label, two-period crossover design to receive a single dose of CER 30 mg on days 1 and 15 (separated by a 14-day drug washout) in either the fed or the fasted state. Pharmacokinetic measures included area under the plasma cyclobenzaprine concentration versus time curve to 168 hours (AUC(168)) and infinity (AUC(infinity)), maximum plasma cyclobenzaprine concentration (C(max)), time to observed C(max) (t(max)), terminal elimination half-life (t(1/2beta)), and absorption lag time (t(lag)). A food effect, as determined from the C(max) and the AUC, was established if the 90% confidence interval (CI) for the ratio of the mean fed/fasted values fell outside the range of 0.80 to 1.25. Adverse events were monitored throughout the study. RESULTS: Sixteen healthy volunteers were enrolled (eight men, eight women; mean age 29.7 years), and 15 completed the study. No appreciable differences in the shape of the mean plasma cyclobenzaprine concentration versus time profile, t(lag) (2 hours) or t(max) (fed: 8 hours; fasted: 6 hours) were noted for CER 30 mg in the fed and fasted states. The least-squares mean ratio of fed to fasted state was 1.21 for AUC(168) (90% CI 1.11, 1.32), 1.20 for AUC(infinity) (90% CI 1.11, 1.31), and 1.36 for C(max) (90% CI 1.17, 1.57), which suggested a food effect. Most adverse events were mild in intensity and were comparable in the fed and fasted states. CONCLUSION: The results of this study show that an increase in systemic exposure is observed when CER 30 mg is taken with food. CER 30 mg was generally well tolerated, with comparable adverse events in both the fed and the fasted states. The increase in exposure did not appear to impact the tolerability of the formulation.

Comparison of steady-state plasma concentrations of armodafinil and modafinil late in the day following morning administration: post hoc analysis of two randomized, double-blind, placebo-controlled, multiple-dose studies in healthy male subjects.

BACKGROUND AND OBJECTIVE: Armodafinil, the R- and longer-lasting isomer of modafinil, may maintain higher plasma drug concentrations compared with racemic modafinil because of stereospecific differences in elimination of its isomers. This analysis set out to compare the steady-state pharmacokinetic profiles of armodafinil and modafinil on a milligram-to-milligram basis following once-daily administration. METHODS: A post hoc analysis of two multiple-dose pharmacokinetic studies in healthy male subjects aged 18-50 years was conducted to compare dose-normalized (200 mg/day) plasma drug concentration and pharmacokinetic data for subjects in each study who completed 7 days of once-daily (morning) administration of armodafinil (n = 34) or modafinil (n = 18). RESULTS: Dose-normalized plasma concentrations of armodafinil on day 7 were higher than those of modafinil, with the greatest differences being observed later in the day. Across the 24-hour dose interval, plasma drug concentration fluctuation and swing were 28% and 42% less, respectively, with armodafinil than with modafinil. In addition, average late-day (3 pm to 7 pm after an 8 am dosing) plasma drug concentrations and partial values for the area under the plasma concentration versus time curve for 7-11 hours after dosing were both 44% higher with armodafinil. CONCLUSIONS: At steady state, armodafinil produces consistently higher plasma drug concentrations late in the day than modafinil when compared on a milligram-to-milligram basis. The distinct pharmacokinetic profile of armodafinil compared with that of the racemate may result in fundamentally different durations of action. These differences between the two medications cannot be made equivalent by increasing the dose of the racemate without introducing potential safety concerns.

Armodafinil and modafinil have substantially different pharmacokinetic profiles despite having the same terminal half-lives: analysis of data from three randomized, single-dose, pharmacokinetic studies.

BACKGROUND AND OBJECTIVE: Armodafinil, a non-amphetamine, wakefulness-promoting medication, is the R- and longer-lasting isomer of racemic modafinil. Armodafinil has been shown to improve wakefulness in patients with excessive sleepiness (ES) associated with treated obstructive sleep apnoea, shift work disorder or narcolepsy. In comparison with modafinil, armodafinil maintains higher plasma concentrations later in the day in healthy subjects. The objective of this analysis was to characterize the pharmacokinetic parameters related to those higher concentrations. METHODS: Data from three randomized studies in healthy adult subjects receiving single doses of either armodafinil (50, 100, 200, 250, 300 or 400 mg) or modafinil (400 mg) were pooled, and subsequently dose-normalized to a 200 mg dose for each drug. Non-compartmental pharmacokinetic parameters were assessed. RESULTS: Armodafinil and modafinil both had a mean single-dose terminal elimination half-life of approximately 13 hours, with similar mean maximum plasma drug concentration (C(max)) and median time to C(max) values. After reaching C(max), plasma concentrations appeared to decline in a monophasic manner with armodafinil, but in a biphasic manner with modafinil due to the initial rapid elimination of its S-isomer. As a result, mean area under the plasma drug concentration versus time curve (AUC) from time zero to the time of the last measurable concentration (AUC(last)) and AUC from time zero to infinity (AUC(infinity)) values were 33% and 40% higher, respectively, with armodafinil compared with modafinil on a milligram-to-milligram basis. CONCLUSIONS: Despite similar half-lives, plasma concentrations following armodafinil administration are higher late in the day than those following modafinil administration on a milligram-to-milligram basis. The different pharmacokinetic profile of armodafinil may result in improved wakefulness throughout the day in patients with ES compared with modafinil.