Single-dose and multiple-dose pharmacokinetics and safety of telbivudine after oral administration in healthy Chinese subjects

The pharmacokinetics of telbivudine, an L-nucleoside with potent activity against hepatitis B virus, was assessed in 42 healthy Chinese volunteers. Subjects were assigned to receive a single oral dose of 200, 400, or 800 mg telbivudine or repeat doses of 600 mg/d. Telbivudine was absorbed rapidly and exhibited dose-related plasma exposure. After reaching maximum concentration (C(max)) at a median time of 2.0 to 2.5 hours, plasma disposition of the drug was biphasic with a mean terminal half-life ranging from 39.4 to 49.1 hours. Telbivudine accumulated slightly after repeat doses, and steady state was reached after 5 to 6 consecutive doses of 600 mg/d. The mean steady-state C(max) and area under the plasma concentration-time curve over the dosing interval of telbivudine 600 mg were 3.7 microg/mL and 26.1 microg x h/mL, respectively. Cumulative urinary excretion of telbivudine over 32 hours represented 24.4% of the administered dose, with a mean renal clearance of 6.6 L/h. Telbivudine was well tolerated in the studied dose range in healthy Chinese subjects, with no pattern of dose-related clinical or laboratory adverse events.     

Single-dose and steady-state pharmacokinetics of fentanyl buccal tablet in healthy volunteers

This study evaluated the single-dose and steady-state pharmacokinetics of fentanyl buccal tablet 400 microg in healthy adult volunteers. After receiving naltrexone 50 mg to block opioid receptor-mediated effects of fentanyl, subjects received fentanyl buccal tablet 400 microg on day 1, then every 6 hours from day 4 to day 9 (21 doses). Naltrexone 50 mg was administered every 12 hours throughout the study. Plasma fentanyl concentrations were determined for 72 hours after administration of fentanyl buccal tablet 400 microg on day 1 and the last dose of fentanyl buccal tablet 400 microg on day 9. Following single- and multiple-dose administration of fentanyl buccal tablet, the median time to maximum concentration (tmax) was 52.2 and 49.8 minutes, respectively. Peak plasma concentration of fentanyl (Cmax) was 0.88 ng/mL for the single-dose regimen and 1.77 ng/mL for the multiple-dose regimen. Steady state was reached within 5 days, consistent with the observed median half-life of approximately 22 hours following multiple doses. Observed accumulation of fentanyl after multiple doses of fentanyl buccal tablet was slightly greater than would be expected based on the single-dose data. This was attributed to the redistribution of fentanyl from a deep tissue compartment into the plasma. This study indicates that fentanyl buccal tablet has predictable pharmacokinetics following multiple-dose administration.     

DOV 216,303, a "triple" reuptake inhibitor: safety, tolerability, and pharmacokinetic profile

This report describes the first evaluation in humans of DOV 216,303, a putative antidepressive that inhibits the reuptake of norepinephrine, serotonin, and dopamine. Subjects received single oral doses of 5 to 150 mg of DOV 216,303 or placebo. At 150 mg, 4 of 7 subjects reported gastrointestinal disturbances. In the multiple-dose phase of the evaluation, subjects received total daily doses of 50, 75, or 100 mg of DOV 216,303 or placebo for 10 days. At a total daily dose of 100 mg, gastrointestinal disturbances were reported in 4 of 6 volunteers. In both the single- and multiple-dose evaluations, no significant changes were noted in vital signs, electrocardiogram, hematology, or clinical chemistry. DOV 216,303 was rapidly absorbed (plasma t(max) of 0.7-1.2 hours and t(1/2) of 3.3-4.4 hours), with dose-proportional C(max) and AUC values. Furthermore, no remarkable difference was apparent in either the C(max) or AUC(tau) of DOV 216,303 following 1 and 10 days of dosing. The present results demonstrate that DOV 216,303 is safe and well tolerated both at single doses of up to 100 mg and multiple doses of up to 100 mg/day for 10 days. Plasma concentrations of DOV 216,303 after doses > 10 mg exceed its reported IC(50) values for inhibition of biogenic amine reuptake.     

Safety and tolerability of aclidinium administered intravenously and absolute bioavailability of inhaled aclidinium in healthy male participants

Aclidinium bromide is a long-acting muscarinic antagonist in development for chronic obstructive pulmonary disease treatment. This 2-part, phase I study evaluated the safety and tolerability of single ascending intravenous (IV) doses of aclidinium to determine its maximum tolerated dose (MTD; part I) and its absolute bioavailability (part II). Healthy male participants (N = 24) were randomized (1:1) in each part: 3-period crossover, placebo-controlled, single-ascending, alternating IV doses of aclidinium (25-400 μg) in part I and 2-period crossover, single-alternating IV and inhaled doses of aclidinium (200 μg) in part II. A ≥7-day washout separated treatment periods. Pharmacokinetic data were collected in both parts. Following IV or inhaled aclidinium, time to reach maximum plasma concentration following drug administration (t(max) ) was 5 to 7 minutes for all doses. After maximum plasma drug concentration (C(max)), aclidinium was rapidly cleared from plasma. Aclidinium absolute bioavailability was <5% following a single inhaled 200-μg dose. Urinary excretion of unchanged aclidinium was very low, with a greater amount of inactive metabolites excreted compared with aclidinium, all of which were recovered within 12 hours postdose. The MTD following IV administration was not reached; all single IV (25-400 μg) and inhaled doses (200 μg) were well tolerated. In conclusion, the low and short-lived bioavailability of aclidinium and the low incidence of systemic side effects contribute to its positive safety and tolerability profile.     

Pharmacokinetics and safety of fentanyl sublingual spray and fentanyl citrate intravenous: a single ascending dose study in opioid-naïve healthy volunteers

Objective: Fentanyl sublingual spray offers rapid pain relief in opioid-tolerant cancer patients, and may be useful in acute or post-operative pain. Both opioid-naïve and non-tolerant patients are likely to receive opioids in these settings. Understanding the relationship between systemic exposure of fentanyl sublingual spray and effects on respiratory function in opioid-naïve or non-tolerant populations is important to ensure patient safety. This study evaluated single-dose fentanyl sublingual spray in opioid-naïve participants.

Research design: Participants were randomized to receive single-dose fentanyl sublingual spray (100, 200, 400, 600, 800?mcg) or fentanyl citrate IV in one of five cohorts. Dosing occurred following a 10-h fast, with fasting continuing for 4?h post-dose. Dose proportionality was assessed using analysis of variance and linear regression techniques. PK assessments and safety monitoring were performed through 24?h post-dose. Safety assessments, including adverse event (AE) monitoring, occurred from dosing through Day 7.

Results: Fifty participants (19?53 years) received fentanyl sublingual spray or fentanyl citrate IV. Mean maximum plasma concentrations were reached between 0.27–0.60?h post-dose for fentanyl sublingual spray. Peak (C_max) and total (AUC_0–t, AUC_0–∞) fentanyl exposures increased in a linear, but more than dose-proportional manner, with higher doses. The most common AEs were somnolence, nausea, and vomiting. All AEs were mild or moderate in severity. Doses at 400, 600, and 800?mcg were associated with nausea and vomiting, requiring pharmacologic intervention. Hypoxia episodes requiring nasal cannula oxygenation were observed with 600mcg and 800mcg doses.

Conclusions: Overall, single-dose fentanyl sublingual spray (100–800?mcg) was generally well tolerated, with greater incidences of AEs (e.g. nausea, vomiting, hypoxia) at higher doses. Doses up to 200?mcg may be safely administered to healthy opioid-naïve individuals with routine monitoring; doses between 400–800?mcg may be administered in settings with nasal cannula oxygenation.     

Single- and multiple-dose pharmacokinetics of pirfenidone, an antifibrotic agent, in healthy Chinese volunteers

A randomized, dose-escalating study evaluated the pharmacokinetics of single and multiple oral doses of pirfenidone, a promising antifibrotic agent, in 48 healthy Chinese volunteers. The effects of sex and food on the pharmacokinetics of pirfenidone were also evaluated. Pharmacokinetics was determined from serial blood samples obtained up to 12 hours after administration of single 200-, 400-, or 600-mg doses of pirfenidone and after multiple doses of 400 mg administrated 3 times daily (tid). Plasma levels of pirfenidone and areas under the curve were found to be proportional to dose. Pirfenidone was rapidly absorbed (t(max) = 0.33-1 hours) and cleared (t((1/2)) = 2-2.5 hours). Pharmacokinetic parameters after multiple doses were similar to those after single doses. Food had a significant effect (P < .01) on the extent of absorption (AUC(0-infinity) = 37.4 +/- 15.4 mg x h/L [fed] vs 46.6 +/- 16.8 mg x h/L [fasted]), rate of absorption was considerably (P < .001) prolonged (t(max) = 1.5 +/- 0.4 hours [fed] vs 0.7 +/- 0.2 hours [fasted]), and peak concentrations were significantly (P < .001) decreased (C(max) = 9.2 +/- 2.9 mg/L [fed] vs 13.0 +/- 1.8 mg/L [fasted]). No significant sex differences were noted for pharmacokinetic variables. Pirfenidone was well tolerated. These results support a tid regimen of pirfenidone for the management of idiopathic pulmonary fibrosis. Concomitant intake of food will reduce the rate and extent (about 20%) of absorption, which is associated with better tolerability of pirfenidone.     

Adrenal effects and pharmacokinetics of CFC-free beclomethasone dipropionate: a 14-day dose-response study.

Since equivalent efficacy is achieved with lower doses of the reformulated beclomethasone dipropionate in the chlorofluorocarbon (CFC)-free propellant HFA-134a (HFA) than with the original CFC-beclomethasone dipropionate formulation, it is possible the HFA-beclomethasone dipropionate may have less safety concerns than the CFC formulation. Despite its chronic use, the steady-state pharmacokinetics of beclomethasone dipropionate has never been studied before. This double-blind study examined adrenal effects and pharmacokinetics after 14 days of dosing with HFA-beclomethasone dipropionate. Forty-three steroid-naïve asthmatic patients were randomised into 5 parallel groups and dosed every 12 h for 14 days with: HFA-placebo; 200, 400 or 800 μg day_-1 HFA-beclomethasone dipropionate; or 800 μg day_-1 CFC-beclomethasone dipropionate. After two weeks of dosing, the 24-h urinary free cortisol of all but one patient remained within the normal range, showing that all doses were well tolerated from a systemic safety perspective. The active HFA-beclomethasone dipropionate treatment groups showed a dose-related fall in 24-h urinary free cortisol. Total-beclomethasone (beclomethasone dipropionate and metabolites) pharmacokinetics after either the first dose of HFA-beclomethasone dipropionate or CFC-beclomethasone dipropionate were not substantially affected by subsequent doses. The extent of drug absorption from 800 μg day_-1 HFA-beclomethasone dipropionate and CFC-beclomethasone dipropionate was in the ratio of 1–7: 1. A non-linear correlation between 24-h urinary free cortisol and the pharmacokinetic parameters was observed, reflecting smaller changes in 24-h urinary free cortisol than in pharmacokinetics as the dose was increased. No clinically meaningful change in the pharmacokinetics of beclomethasone dipropionate plus metabolites was seen on multiple dosing. The greater systemic availability of HFA-beclomethasone dipropionate was still associated with adrenal effects comparable with that of the CFC formulation at the same dose.     

Assay validation for vilanterol and its metabolites in human urine with application for doping control analysis

A bioanalytical method for detecting the ultra-long-acting beta₂-agonist (U-LABA) inhaled vilanterol and its metabolites, GSK932009 and GW630200, in urine was developed to potentially monitor permitted therapeutic versus prohibited supratherapeutic use in sport. The World Anti-Doping Agency (WADA) has established urinary concentration thresholds for the beta₂-agonists salbutamol and formoterol. Therapeutic use of vilanterol (25 μg once daily) was recently permitted by WADA; however, there is no established decision limit for adverse analytical findings due to insufficient urine concentration data. In this study, we validated an assay to detect vilanterol in urine collected from four healthy male and female athletes 0–72 h who received inhaled corticosteroid fluticasone furoate/U-LABA vilanterol (800/100 μg) combination, four times the normal therapeutic dose. After administration, subjects performed 1 h of bike ergometer exercise. The experiment was conducted again after repeat dosing for 1 week. Our method utilised liquid chromatography with tandem mass spectrometry and was validated over urine concentrations of 5–5000 (vilanterol) and 50–50,000 pg/ml (GSK932009 and GW630200). Plasma samples were analysed for vilanterol, using a previously validated assay. The peak concentration values for urine vilanterol, GSK932009 and GW630200 were 9.5, 10.4 and 0.17 ng/ml, for single dosing, and 18.6, 19.5 and 0.20 ng/ml, for repeat dosing. Urine samples from four volunteers using the final validated method are reported, demonstrating this assay has sensitivity to detect vilanterol or GSK932009 in urine for ≥72 h post single or repeat dosing with 800/100 μg fluticasone furoate/vilanterol, whereas GW630200 was quantifiable ≤4 h post dose.     

Bioequivalence following buccal and sublingual placement of fentanyl buccal tablet 400 microg in healthy subjects

BACKGROUND AND OBJECTIVE: The fentanyl buccal tablet (FBT) is formulated to enhance the rate and extent of fentanyl absorption across the buccal mucosa. FBT is indicated for the management of breakthrough pain (a transient flare of pain on a background of chronic pain otherwise controlled by treatment with opioids) in patients with cancer who are already receiving and who are tolerant to opioid therapy for their underlying persistent cancer pain. This study assessed the bioequivalence of a single 400-microg dose of FBT following buccal (i.e. above a molar tooth between the upper gum and cheek) and sublingual (i.e. placed under the tongue) placement in order to provide an alternative option to patients. METHODS: Healthy subjects were randomized to receive one FBT 400 microg buccally and sublingually (with naltrexone to minimize opioid effects) in an open-label, crossover design. Bioequivalence, as determined from the maximum plasma drug concentration (C(max)) and the area under the plasma drug concentration-time curve from time 0 to infinity (AUC(infinity)), was established if the 90% confidence interval (CI) for the ratio of the means of sublingual/buccal values fell within the range of 0.80 to 1.25. RESULTS: Ninety subjects were enrolled (67 men, 23 women; median age 24 years), and 78 completed the study. The criteria for bioequivalence were met for both C(max) and AUC(infinity) for the two sites of tablet placement: sublingual/buccal ratio for C(max) = 0.868 (90% CI 0.815, 0.924); sublingual/buccal ratio for AUC(infinity) = 0.947 (90% CI 0.901, 0.995). Buccal and sublingual placement resulted in similar values for both AUC from time 0 to t(max') (AUC(tmax')), where t(max') is the median time to C(max) of a single 400-microg dose of FBT administered buccally (mean [SD]: 0.35 [0.16] ng . h/mL buccal; 0.35 [0.16] ng . h/mL sublingual) and for time to C(max) (median [range]: 0.75 [0.33-3.13] hours buccal; 0.78 [0.17-3.00] hours sublingual). FBT was generally well tolerated following placement at both sites in healthy volunteers administered naltrexone. CONCLUSION: The results of this study support sublingual FBT placement as a viable alternative to buccal placement in patients who may require an alternate administration site.     

Safety, tolerability, pharmacokinetics, and pharmacodynamic properties of taranabant, a novel selective cannabinoid-1 receptor inverse agonist, for the treatment of obesity: results from a double-blind, placebo-controlled, single oral dose study in healthy volunteers

Taranabant is a novel cannabinoid CB-1 receptor (CB1R) inverse agonist in clinical development for the treatment of obesity. This double-blind, randomized, placebo-controlled, single oral dose study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of taranabant (0.5-600 mg) in 24 healthy male volunteers. Single-dose AUC(0-infinity) and C(max) values for taranabant increased approximately linearly with dose up to 200 mg, with slightly less than dose-proportional increases in AUC(0-infinity) and C(max) values for doses >200 mg. Plasma taranabant had a biphasic disposition, with a median t(max) of 1 to 2.5 hours and a terminal elimination t((1/2)) of 38 to 69 hours. Coadministration of taranabant with a high-fat meal led to a 14% increase in C(max) and a 74% increase in AUC(0-infinity). Clinical adverse experiences associated with single doses of taranabant were generally mild and transient. Of the 198 clinical adverse experiences reported, the most common drug-related ones were nausea (36), headache (22), drowsiness (14), abdominal discomfort/abdominal pain/stomachache (14), hiccups (9), dizziness (8), decreased appetite (7), increased bowel movement (7), mood change (6), tiredness (4), vomiting (4), and sweating increased (4). Taranabant has pharmacokinetic characteristics suitable for a once-daily dosing regimen.     

An overview of the pharmacokinetics of cilomilast (Ariflo), a new, orally active phosphodiesterase 4 inhibitor, in healthy young and elderly volunteers

The oral pharmacokinetics of cilomilast (Ariflo) were investigated in five separate studies in healthy volunteers. Cilomilast was rapidly absorbed, and pharmacokinetics were dose proportional after single and repeat dosing. The elimination half-life was 7 to 8 hours; accordingly, steady state was reached on the 3rd day of dosing. The degree of accumulation following repeat twice-daily dosing was predictable from the data following a single dose. Although systemic exposure (AUC) was, on average, 21% higher in elderly (65-84 years) compared with young subjects, values for Cmax and t(1/2) were similar, and no difference in tolerability was noted. Single and repeat doses of cilomilast up to and including 15 mg (dosed before or taken between meals) were well tolerated. Dosing with food reduced the rate of absorption without affecting total bioavailability. Hence, tolerability was optimal in the fed state; repeat doses up to and including 30 mg twice daily aftermeals were well tolerated following dose titration.     

Absolute and relative bioavailability of fentanyl buccal tablet and oral transmucosal fentanyl citrate

This study assessed the absolute and relative bioavailabilities and transmucosal and gastrointestinal absorbency of fentanyl buccal tablet (FBT) and oral transmucosal fentanyl citrate (OTFC). In a randomized crossover design, 26 healthy subjects received FBT 400 microg (transmucosal), FBT 800 microg (oral), OTFC 800 microg (transmucosal), and fentanyl 400 microg (intravenous). The transmucosal FBT had the highest absolute bioavailability (0.65) compared with the oral FBT (0.31) or transmucosal OTFC (0.47). More fentanyl was absorbed transmucosally from FBT than OTFC (48% vs 22%). Median t(max) values were shorter following the transmucosal FBT (47 minutes) than the oral FBT (90 minutes) or the transmucosal OTFC (91 minutes). Transmucosal administration of FBT compared with dose-normalized OTFC resulted in higher total systemic fentanyl exposure, higher early systemic exposure, and higher C(max). The rate and extent of fentanyl absorption were greater following administration of FBT compared to OTFC. An approximately 30% smaller dose of FBT achieved systemic exposures comparable to OTFC.     

Pharmacokinetics and tolerability of different doses of fentanyl following sublingual administration of a rapidly dissolving tablet to cancer patients: a new approach to treatment of incident pain

AIMS: It is estimated that two-thirds of cancer patients will at some point during their illness experience breakthrough pain. In this study, the pharmacokinetics of a novel sublingual dosage form of fentanyl developed for breakthrough pain was evaluated. METHODS: Eleven Caucasian patients (seven male and 4 female, aged 34-75 years, median 60 years) with metastatic malignant disease were recruited initially, but three patients withdrew. Prior to the study all patients were on continuous nonfentanyl opiate medication. The study was a double-blind, cross-over trial, consisting of three 1-day treatment periods. A new rapidly dissolving preparation of fentanyl, was administered sublingually in single doses of 100, 200 and 400 microg, respectively, on three separate occasions. Plasma fentanyl concentrations were determined using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). Pharmacokinetic parameters were calculated by noncompartment analysis. Tolerability and the occurrence of adverse events were monitored throughout the study by patient questionnaire. RESULTS: The data from nine subjects who completed at least two periods were used in the analysis of variance. There were no significant differences between doses (100, 200 and 400 microg) for dose adjusted AUC (F = 0.42, P = 0.6660), dose adjusted C(max) (F = 0.08, P = 0.9206) and Tmax (F = 0.94, P = 0.4107). Thus, these parameters showed dose proportionality. The differences (400-100microg) in dose adjusted AUC from the three-period crossover analysis was -0.016 min.ng/ml (t = 0.71, P = 0.8718). Interindividual variability in systemic exposure to fentanyl was fairly small (25-40%), which may be related to a good in vivo biopharmaceutical performance of the sublingual tablet, and a relatively small fraction of the dose being swallowed. The first detectable plasma concentration of fentanyl was observed between 8 and 11 min after administration. t(max) increased from 39.7 +/- 17.4 to 48.7 +/- 26.3 and 56.7 +/- 24.6 min for the 100, 200 and 400 microg doses, respectively. Adverse events were few and did not increase with increasing dose. CONCLUSION: With this rapidly dissolving fentanyl formulation, the first detectable plasma concentration of fentanyl was observed at 8-11 min after administration. The pharmacokinetics of the drug showed dose proportionately. This formulation of fentanyl seemed to be well tolerated by the patients.     

Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers

STUDY OBJECTIVE: To determine whether daily high-dose vitamin C alters the steady-state pharmacokinetics of indinavir, a protease inhibitor indicated for treatment of the human immunodeficiency virus type 1. DESIGN: Prospective, open-label, longitudinal, two-period time series. SETTING: University medical center. SUBJECTS: Seven healthy volunteers. INTERVENTION: Indinavir 800 mg every 8 hours was given to subjects for four doses on days 1 and 2. Plasma samples were then collected for indinavir pharmacokinetic determination. After a 7-day washout period, subjects were given vitamin C 1000 mg/day for 7 days. Beginning on day 6 of vitamin C administration, indinavir 800 mg every 8 hours was restarted for four doses. Plasma was then collected from subjects to determine indinavir pharmacokinetics. All subjects were given a vitamin C content-controlled diet for 1 week before the study began and throughout the study period. MEASUREMENTS AND MAIN RESULTS: Steady-state plasma samples were collected before dosing (0 hr) and 0.5, 1, 2, 3, 4, and 5 hours after dosing to determine indinavir pharmacokinetics. Parameters of interest were maximum plasma concentration (C max ), time to C max , area under the plasma concentration-time curve from 0-5 hours after the dose (AUC 0-5 ), an extrapolated 8-hour AUC (AUC 0-8 ), trough (minimum) plasma concentration (C min ), and oral clearance. Mean steady-state indinavir C max was significantly reduced (20%) after 7 days of vitamin C administration (10.3 +/- 1.5 vs 8.2 +/- 2.9 microg/ml, p=0.04). The corresponding mean AUC 0-8 was also significantly decreased (14%; 26.4 +/- 7.2 vs 22.7 +/- 8.1 microg*hr/ml, p=0.05). Although not statistically significant, the mean indinavir C min was 32% lower in the presence of vitamin C (0.27 +/- 0.17 C vs 0.18 +/- 0.08 microg/ml, p=0.09). Indinavir oral clearance and half-life were not significantly different. CONCLUSION: Concomitant administration of high doses of vitamin C can reduce steady-state indinavir plasma concentrations. Subtherapeutic concentrations of antiretroviral agents have been associated with viral resistance and regimen failure, but the clinical significance of our findings remains to be established.     

Aclidinium bromide, a long-acting antimuscarinic, does not affect QT interval in healthy subjects

In this phase I trial, the effect of aclidinium, a novel, inhaled long-acting muscarinic antagonist, on QT interval was evaluated, and its cardiovascular safety was assessed in 272 healthy subjects. Aclidinium 200 μg, aclidinium 800 μg, matching placebo, or open-label moxifloxacin 400 mg was administered daily for 3 days. The primary outcome was mean change in individual heart rate-corrected QT interval (QTcI). Secondary measures included Bazett-corrected QT interval (QTcB), Fridericia-corrected (QTcF) intervals, 12-lead electrocardiogram (ECG) readings, and 24-hour 12-lead Holter ECG parameters. Adverse events, vital signs, and laboratory and pharmacokinetic parameters were also assessed. Maximum mean QTcI change from time-matched baseline on day 3 was -1.0 milliseconds at 2 hours for aclidinium 200 μg, -1.8 milliseconds at 5 minutes for 800 μg, +11.0 milliseconds at 4 hours for moxifloxacin, and -1.2 milliseconds at 23.5 hours for placebo. Aclidinium had no significant effects on secondary ECG measures. Aclidinium plasma concentrations were generally below the lower limit of quantitation (0.05 ng/mL) after 200 μg and were detected only up to 1 hour after the 800-μg dose in the majority of cases. It is concluded that aclidinium bromide, at doses up to 800 μg, has a favorable cardiovascular safety profile with no effect on QT interval.     

Pharmacokinetics,dose proportionality,and tolerability of single and repeat doses of a nasal spray formulation of zolmitriptan in healthy volunteers

The objective of this study was to investigate the pharmacokinetics, dose proportionality, and tolerability of a range of single and multiple doses of a nasal spray formulation of zolmitriptan in a randomized, double-blind, placebo-controlled, balanced, incomplete crossover study. Thirty healthy male or female volunteers received two of five dose levels of zolmitriptan nasal spray: 0 (placebo), 0.5, 1, 2.5, and 5 mg. At each level, treatment comprised a single dose on day 1 and two doses (separated by 2 h) on each of days 2, 3, and 4. Zolmitriptan was well tolerated, and symptoms were generally mild and of short duration. The most commonly reported adverse events were taste disturbance, paresthesia, hyperesthesia, headache, and nasal/throat discomfort. Volunteers generally reported fewer adverse events during the multiple-dose phase than after the single-dose phase. Zolmitriptan was detectable in plasma within 15 minutes, and t(max) was similar for each dose and after single and multiple dosing. Dose proportionality was shown for the C(max) and AUC of both zolmitriptan and its active metabolite, 183C91. Mean t1/2 for zolmitriptan and 183C91 was approximately 3 hours. It was concluded that the pharmacokinetics (C(max) and AUC) for both zolmitriptan and 183C91 was proportional to dose after both single and multiple dosing. Nasal spray zolmitriptan was well tolerated; the frequency and nature of adverse events did not increase after multiple dosing.     

Randomized 5-treatment crossover study to assess the effects of external heat on serum fentanyl concentrations during treatment with transdermal fentanyl systems

This randomized, open-label, 5-treatment, 5-sequence crossover study was designed to evaluate the effects of a heating pad on serum fentanyl concentrations with reservoir and matrix transdermal fentanyl systems. Subjects were randomized to 1 of 5 treatment sequences, receiving 5 fentanyl treatments (1 per period) for 36 hours: 25 μg/h reservoir without heat, 25 μg/h reservoir with heat, 25 μg/h matrix without heat, 25 μg/h matrix with heat, and a 50 μg/h reservoir without heat. The 25 μg/h systems with heat had a heating pad applied from 0 to 10 and 26 to 36 hours post application. Washout periods between treatments were 5 to 14 days. Naltrexone was given to block the opioid effects of fentanyl. Study results indicate that external heat had a similar effect on both matrix and reservoir systems, with heat applied during the first 10 hours of treatment increasing fentanyl exposure by approximately 61% to 81% at 10 hours (observed serum concentration at 10 hours) and overall exposure (area under the curve from 0 to 10 hours) by approximately 120% to 184%, but had minimal effect from 26 to 36 hours. The increased exposure observed with heat in both 25 μg/h systems, between 0 and 10 hours, was higher than that obtained with the 50 μg/h reservoir system applied without heat.     

Pharmacokinetics and safety of fentanyl sublingual spray and fentanyl citrate intravenous: a multiple ascending dose study in opioid-naïve healthy volunteers

Objective: Fentanyl sublingual spray, with its rapid onset for pain relief, may be efficacious in the management of acute or post-operative pain. Because patients in these settings may be opioid-naïve, the study was conducted to determine the safety, tolerability, and pharmacokinetics of multiple dose administration of fentanyl sublingual spray in an opioid-naïve population.

Methods: Fentanyl sublingual spray (100?mcg, 200?mcg, and 400?mcg) and fentanyl citrate intravenous (IV; 50?mcg) were administered every 0.5, 1.0, 2.0, and 4.0?h for up to three doses per cohort in opioid-naïve subjects (ClinicalTrials.gov identifier: NCT02641340). Eight subjects in each cohort were randomly assigned (six subjects received fentanyl sublingual spray; two subjects received fentanyl citrate IV). Pharmacokinetic and safety-related pharmacodynamic assessments were performed through 24?h post-first dose. Safety assessments were collected through Day 7.

Results: Ninety-six opioid-naïve subjects, aged 20–55 years, with a body mass index of 18.7–31.5?kg/m², participated in the study. Multiple doses of fentanyl sublingual spray (100, 200, and 400?mcg) were generally well tolerated. Hypoxia, observed in the 200-mcg and 400-mcg dose groups, increased with increasing doses and higher dosing frequency, but was readily managed by nasal cannula oxygenation. Overall, nausea increased with increasing doses, and ～52.6% (10 out of 19) cases of nausea that occurred at the highest dose of 400?mcg were treated with concomitant medication. Overall, the reported adverse events were consistent with the known safety profile of fentanyl.

Conclusion: Fentanyl sublingual spray (100?mcg, 200?mg, and 400?mcg) administered every 0.5, 1, 2, and 4?h was generally well tolerated in an opioid-naïve population. The results suggest that doses of 200?mcg or lower may be safe for use in an opioid-naïve population.     

Multiple-dose pharmacokinetics, pharmacodynamics, and safety of taranabant, a novel selective cannabinoid-1 receptor inverse agonist, in healthy male volunteers

Taranabant is a cannabinoid-1 receptor inverse agonist for the treatment of obesity. This study evaluated the safety, pharmacokinetics, and pharmacodynamics of taranabant (5, 7.5, 10, or 25 mg once daily for 14 days) in 60 healthy male subjects. Taranabant was rapidly absorbed, with a median t(max) of 1.0 to 2.0 hours and a t(1/2) of approximately 74 to 104 hours. Moderate accumulation was observed in C(max) (1.18- to 1.40-fold) and AUC(0-24 h) (1.5- to 1.8-fold) over 14 days for the 5-, 7.5-, and 10-mg doses, with an accumulation half-life ranging from 15 to 21 hours. Steady state was reached after 13 days. After multiple-dose administration, plasma AUC(0-24 h) and C(max) of taranabant increased dose proportionally (5-10 mg) and increased somewhat less than dose proportionally for 25 mg. Taranabant was generally well tolerated up to doses of 10 mg and exhibited multiple-dose pharmacokinetics consistent with once-daily dosing.     

Tolerability, pharmacokinetics and concentration-dependent hemodynamic effects of oral CF101, an A3 adenosine receptor agonist, in healthy young men

OBJECTIVES: To assess safety, tolerability, pharmacokinetics and hemodynamic effects of oral CF 101, an A3 adenosine receptor (A3AR) agonist, in healthy men. METHODS: One single and 1 repeated dose, parallel-group, ascending dose, double-blind and placebo-controlled study in normal volunteers. In the single dose study, n = 15 subjects received 1, 5 or 10 mg oral CF101; in each group 1 subject received placebo, the remainder active CF101. In the repeat-dose study, n = 28 subjects received repeated 12-hourly oral doses of CF 101 (2, 3, 4 or 5 mg) for 7 days, in each group 2 subjects received placebo, the remainder active CF101. TEST MATERIALS: Single-dose study: CF101 in 30% Cremophor RH40. Multiple-dose sudy: CF101 in 0.5% methylcellulose suspension. Both studies: the corresponding vehicles were used as placebos. Galenicals were prepared remotely from the clinical study site to ensure double-blind nature of the study. RESULTS TOLERABILITY: Single doses up to 5 mg CF101 were safe and well-tolerated. However, the single dose of 10 mg CF101 was associated with flushing, tachycardia, nausea and vomiting, which were viewed as dose-limiting in normal volunteers. Single doses of CF101 (as well as the first of the multiple doses) were associated with increases in heart rate (8 - 24 beats/min after 5 mg and 18 - 55 beats/min after 10 mg). Multiple doses up to 4 mg 12-hourly for 7 days were safe and well-tolerated. However, the 5 mg multiple-dose group reported headache, drowsiness, hot flushes and dizziness on standing; this declined with dosing duration and was not dose-limiting in this study. Adverse events were commonest near t(max). RESULTS PHARMACOKINETICS: For oral CF101, the t(max) was always 1 - 2 h post-dose and t 1/2 about 9 h, in both the single- and multiple-dose studies. For a single 5 mg dose (mean +/- SD) C(max) = 81.6 +/- 23.6 ng/ml in the single dose study, and 63.6 +/- 22.0 ng/ml after the first of the multiple doses; AUC if was 904.0 +/- 221.9 ng.h/ml and 596.1 +/- 196.6 ng.h/ml for the 2 studies, respectively. After 7 days of multiple dosing there was little change, and AUC(0-24h) = 601.0 +/- 163.6 ng.h/ml. These pharmacokinetic parameters were linearly proportional to dose in the other treatment groups. RESULTS PHARMACODYNAMICS: Increases in heart rate were related to plasma concentration and evident only in the upper range of concentrations observed. There were no changes on ECG monitoring beyond sinus tachycardia, and, in particular, no evidence of PR prolongation in any subject (n = 43). In comparison with single doses, this response was almost absent after 7 days of dosing. Leucocytosis (increases up to about 1.5 x 10(9)/l after 5 and 10 mg) was similarly transient and reversible after multiple dosing. CONCLUSIONS: Single oral doses up to 5 mg CF101 and repeated doses up to 4 mg 12-hourly for 7 days were safe and well-tolerated. Multiple-dose CF101 pharmacokinetics were unchanged and predictable from single-dose estimates, and were linearly proportional to dose. Increases in heart rate and neutrophil count were reversible during multiple dosing and were not dose-limiting in the repeat dose study. CF101 warrants further study for its efficacy in treating human disease.