Safety, Pharmacokinetics, and Pharmacodynamics of Trazpiroben (TAK-906), a Novel Selective D2 /D3 Receptor Antagonist: A Phase 1 Randomized, Placebo-Controlled Single- and Multiple-Dose Escalation Study in Healthy Participants.

Gastroparesis is a chronic neuromuscular disorder of the upper gastrointestinal tract in which episodic exacerbation can lead to frequent hospitalizations and severe disability. Dopamine D2 /D3 receptor antagonists have been used to treat patients with gastroparesis with some efficacy; however, their chronic use is limited owing to associated central nervous system (CNS) or cardiovascular safety concerns. Trazpiroben (TAK-906) is a dopamine D2 /D3 receptor antagonist under development for the long-term treatment of gastroparesis. Preclinical studies in rat and dog have shown trazpiroben to have minimal brain penetration and low affinity for the human ether-à-go-go-related gene (hERG) potassium channel (IC50 ,  15.6 µM), thereby reducing the risk of the CNS and cardiovascular adverse effects seen with other dopamine D2 /D3 receptor antagonists. This phase 1 trial evaluated the safety, pharmacokinetics, and pharmacodynamics of trazpiroben in healthy participants. Trazpiroben was rapidly absorbed and eliminated (Tmax , ∼1.1 hours; t1/2 , 4-11 hours) after administration of single (5-300 mg) and multiple (50 or 100 mg) doses. Receptor target engagement was confirmed for all doses, as indicated by an increase in serum prolactin levels compared with placebo (mean prolactin Cmax , 134.3 ng/mL after administration of trazpiroben 10 mg vs 16.1 ng/mL with placebo). Therapeutically relevant single and multiple doses of trazpiroben were well tolerated in healthy participants, and no clinically meaningful cardiovascular adverse effects were observed across the whole dose range. These data support the further development of trazpiroben for the treatment of gastroparesis.

Safety, pharmacokinetics, and immunogenicity of a co-formulated cocktail of three human monoclonal antibodies targeting Ebola virus glycoprotein in healthy adults: a randomised, first-in-human phase 1 study.

BACKGROUND: REGN3470-3471-3479 is a co-formulated cocktail of three human monoclonal antibodies targeting three non-overlapping epitopes on Ebola virus. We investigated safety, tolerability, pharmacokinetics, and anti-drug antibodies in healthy adults. METHODS: This randomised, double-blind, placebo-controlled, dose-escalation study was done at a phase 1 unit in the USA. Healthy adults, aged 18-60 years, with a body-mass index of 18·0-30·0 kg/m2 were randomly assigned (3:1) to receive a single intravenous dose of REGN3470-3471-3479 or placebo on day 1 (baseline) in one of the four sequential ascending intravenous dose cohorts (3 mg/kg, 15 mg/kg, 60 mg/kg, and 150 mg/kg). Site investigators and participants were masked to the treatment assignment, whereas designated personnel at the site who prepared and generated the study medication were aware of the randomisation treatment assignments. The primary outcome was safety and the secondary outcomes were the pharmacokinetic profiles and immunogenicity. Study assessments were done the day before study drug administration, on the day of drug administration, on day 2 (before discharge), on days 3, 4, 8, 15, 29, 57, 85, 113, and 141, and at the end of study on day 169. The safety analysis included all randomised participants who received study drug. This trial is registered with ClinicalTrials.gov, number NCT002777151. FINDINGS: Between May 18, 2016, and October 27, 2016, 70 adults were screened and 24 participants were enrolled in the study. 18 participants were assigned to and received REGN3470-3471-3479, and six participants were assigned to and received placebo as a single intravenous infusion. 19 treatment-emergent adverse events occurred in the combined REGN3470-3471-3479 treatment groups, and four treatment-emergent adverse events occurred in combined placebo groups. Adverse events were transient and mild-to-moderate in severity. The most common treatment-emergent adverse event was headache (six [33%] of 18 participants in the combined REGN3470-3471-3479 group vs none of six participants in the placebo group. Headaches were mild-to-moderate in severity, with onset between 2 h and 27 days after start of study drug infusion. There were no deaths, serious adverse events, or adverse events that led to study discontinuation. The pharmacokinetics of each antibody was linear, with mean half-lives of 27·3 days for REGN3471, 21·7 days for REGN3470, and 23·3 days for REGN3479. No participants tested positive for anti-REGN3470, anti-REGN3471, or anti-REGN3479 antibodies. INTERPRETATION: REGN3470-3471-3479 was well tolerated, displayed linear pharmacokinetics, and did not lead to detectable immunogenicity. These data support further clinical development of REGN3470-3471-3479 as a single-dose therapeutic drug for acute Ebola virus infection. FUNDING: The Department of Health and Human Services, the Office of the Assistant Secretary for Preparedness and Response, and the Biomedical Advanced Research and Development Authority.

CK-2127107 amplifies skeletal muscle response to nerve activation in humans.

INTRODUCTION: Three studies evaluated safety, tolerability, pharmacokinetics, and pharmacodynamics of CK-2127107 (CK-107), a next-generation fast skeletal muscle troponin activator (FSTA), in healthy participants. We tested the hypothesis that CK-107 would amplify the force-frequency response of muscle in humans. METHODS: To assess the force-frequency response, participants received single doses of CK-107 and placebo in a randomized, double-blind, 4-period, crossover study. The force-frequency response of foot dorsiflexion following stimulation of the deep fibular nerve to activate the tibialis anterior muscle was assessed. RESULTS: CK-107 significantly increased tibialis anterior muscle response with increasing dose and plasma concentration in a frequency-dependent manner; the largest increase in peak force was ∼60% at 10 Hz. DISCUSSION: CK-107 appears more potent and produced larger increases in force than tirasemtiv-a first-generation FSTA-in a similar pharmacodynamic study, thereby supporting its development for improvement of muscle function of patients. Muscle Nerve 57: 729-734, 2018.

The Absolute Bioavailability and Effect of Food on the Pharmacokinetics of Odanacatib: A Stable-Label i.v./Oral Study in Healthy Postmenopausal Women.

A stable-label i.v./oral study design was conducted to investigate the pharmacokinetics (PK) of odanacatib. Healthy, postmenopausal women received oral doses of unlabeled odanacatib administered simultaneously with a reference of 1 mg i.v. stable (13)C-labeled odanacatib. The absolute bioavailability of odanacatib was 30% at 50 mg (the phase 3 dose) and 70% at 10 mg, which is consistent with solubility-limited absorption. Odanacatib exposure (area under the curve from zero to infinity) increased by 15% and 63% when 50 mg was administered with low-fat and high-fat meals, respectively. This magnitude of the food effect is unlikely to be clinically important. The volume of distribution was ∼100 liters. The clearance was ∼0.8 l/h (13 ml/min), supporting that odanacatib is a low-extraction ratio drug. Population PK modeling indicated that 88% of individuals had completed absorption of >80% bioavailable drug within 24 hours, with modest additional absorption after 24 hours and periodic fluctuations in plasma concentrations contributing to late values for time to Cmax in some subjects.

A Randomized Phase 1 Dose Escalation Study to Evaluate Safety, Tolerability, and Pharmacokinetics of Trabodenoson in Healthy Adult Volunteers.

PURPOSE: To investigate the safety, tolerability, and pharmacokinetics of trabodenoson, a highly selective adenosine mimetic targeting the adenosine A1 receptor. METHODS: In Part 1, 60 healthy adult volunteers were randomized to 14 days of twice-daily topical monocular application of placebo or trabodenoson (200, 400, 800, 1,600, 2,400, or 3,200 µg). In Part 2, 10 subjects were randomized to placebo or 8 escalating doses of bilateral trabodenoson (total daily doses: 1,800-6,400 µg). RESULTS: The incidence of treatment-related adverse events in Part 1 was similar in the trabodenoson (27.8%) and placebo (25.0%) groups. Most were mild in intensity. The most common adverse events (AEs) for trabodenoson and placebo were headache (25.0% vs. 33%, respectively) and eye pain (11.1% vs. 4.2%, respectively). Ocular AEs were infrequent (16.7% and 17.9%, respectively), were self-limited, lasted <24 h, and were typically mild in intensity. The most common ocular AE was eye pain (9.5% and 3.6%, respectively), with a single observation of ocular hyperemia (200 µg trabodenoson). Trabodenoson was rapidly absorbed [median time to maximum concentration (tmax): ∼0.08 to 0.27 h] and eliminated (t½: 0.48-2.0 h), with no evidence of drug accumulation. Systemic exposure to topical trabodenoson was dose related but not dose proportional, with a plateau effect at doses ≥2,400 mg per eye. No clinically significant treatment-related systemic AEs were observed, and increasing systemic exposure had no effect on heart rate or blood pressure. CONCLUSIONS: Ocular doses of trabodenoson up to 3,200 µg per eye were safe and well tolerated in the eye and resulted in no detectable systemic effects in healthy adult volunteers.

Effect of ceralifimod (ONO-4641) on lymphocytes and cardiac function: Randomized, double-blind, placebo-controlled trial with an open-label fingolimod arm.

This randomized, double-blind, placebo-controlled, 6-arm, parallel-design study investigated cardiac and hematological pharmacodynamic effects of ceralifimod (ONO-4641), a selective sphingosine-1-phosphate (S1P) receptor modulator, over a broad dose range in direct comparison with the nonselective S1P modulator fingolimod. Healthy subjects were assigned to ceralifimod (0.01, 0.025, 0.05, or 0.10 mg), fingolimod (0.5 mg), or placebo once daily for 14 days (n = 24 per group). After 14 days of treatment, mean absolute lymphocyte count percentage change from baseline was greatest in the fingolimod (-62%) and ceralifimod 0.10 mg (-56%) groups. On treatment cessation, lymphocyte recovery was faster in the ceralifimod versus the fingolimod group. Ceralifimod showed dose- and concentration-dependent chronotropic effect. Cardiac effects in the fingolimod group were dependent on fingolimod-P concentrations. Maximum mean heart rate (HR) effect on day 1 was larger with fingolimod (placebo-adjusted change from time-matched baseline HR [ΔΔHR], -14.9 beats per minute [bpm]) versus ceralifimod (ΔΔHR, -6.2 and -12.0 bpm for the 0.05- and 0.10-mg doses, respectively). Ceralifimod's effect on the PR interval was minor. Safety biomarker results suggest that potential therapeutic doses of ceralifimod, in particular the 0.05-mg dose, might result in reduced occurrence of bradycardia, atrioventricular block absolute lymphocyte count and grade 3/4 lymphopenia compared with fingolimod 0.5 mg.

A thorough QT study in the context of an uptitration regimen with selexipag, a selective oral prostacyclin receptor agonist.

The effects of selexipag and its active metabolite ACT-333679 on cardiac repolarization were assessed in a thorough QT study as per International Conference on Harmonisation E14 guidance. In this randomized, double-blind, placebo/positive-controlled, parallel-group study, healthy male and female subjects were randomized to receive escalating doses of selexipag (n=91) or placebo/moxifloxacin (n=68). Ascending multiple doses of selexipag in the range of 400-1,600 µg or placebo were administered twice daily for 21 days. Following a nested crossover design, subjects in the moxifloxacin/placebo treatment group received a single oral 400 mg dose of moxifloxacin on day 2 or 24. The primary endpoint (QT interval correction using individualized formula [QTcI]) was chosen based on a prospectively defined test applied to on-treatment data. The mean baseline-adjusted placebo-corrected ΔQTcI (ΔΔQTcI) for selexipag was small at all time points and never exceeded 1.4 msec (upper bound of 90% confidence interval [CI], 3.9 msec) on 800 µg or -0.7 msec (upper bound of 90% CI, 2.1 msec) on 1,600 µg. The mean ΔΔQTcI peak effect for moxifloxacin was 7.5 msec (lower bound of 90% CI, 4.8 msec). The exposure-response analysis did not demonstrate a relevant relationship between plasma concentrations of selexipag or ACT-333679 and ΔΔQTcI but, in contrast, a positive slope within the expected range for moxifloxacin. In conclusion, selexipag does not have an effect on cardiac repolarization.

Inhaled loxapine and intramuscular lorazepam in healthy volunteers: a randomized placebo-controlled drug-drug interaction study.

Pharmacodynamic effects and safety of single-dose inhaled loxapine administered via the Staccato(®) system and intramuscular (IM) lorazepam in combination versus each agent alone were compared in a randomized, double-blind, crossover study in healthy volunteers. Subjects received: inhaled loxapine 10 mg + IM lorazepam 1 mg; inhaled loxapine 10 mg + IM placebo; IM lorazepam 1 mg + Staccato placebo in random order, each separated by a 3-day washout. Primary endpoints were maximum effect (minimum value) and area under the curve (AUC) from baseline to 2 h post treatment for respirations/min and pulse oximetry. Least-squares means (90% confidence interval [CI]) for concomitant treatment versus each agent alone were derived and equivalence (no difference) confirmed if the 90% CI was within 0.8-1.25. Blood pressure (BP), heart rate (HR), sedation (100-mm visual analog scale), and adverse events (AEs) were recorded. All 18 subjects (mean age, 20.4 years; 61% male) completed the study. There was no difference between inhaled loxapine + IM lorazepam and either agent alone on respiration or pulse oximetery during the 12-h postdose period, confirmed by 90% CIs for AUC and C min ratios. BP and HR were no different for inhaled loxapine + IM lorazepam and each agent alone over a 12-h postdose period. Although the central nervous system sedative effects were observed for each treatment in healthy volunteers, the effect was greater following concomitant lorazepam 1 mg IM + inhaled loxapine 10 mg administration. There were no deaths, serious AEs, premature discontinuations due to AEs, or treatment-related AEs.

Effect of ponesimod, a selective S1P1 receptor modulator, on the QT interval in healthy individuals.

Ponesimod is an orally active selective sphingosine-1-phosphate receptor 1 modulator under investigation for the treatment of multiple sclerosis. This was a single-centre, double-blind, randomized, placebo- and positive-controlled parallel-group study investigating the effects of ponesimod on the QTc interval in healthy individuals. A nested cross-over comparison between moxifloxacin and placebo was included in the combined moxifloxacin/placebo treatment group. Subjects in group A received multiple doses of 10-100 mg ponesimod according to an uptitration regimen on days 2-23 and moxifloxacin-matching placebo on days 1 and 24. Subjects in group B received ponesimod-matching placebo on days 2-23 and were randomized to receive either a single dose of 400 mg moxifloxacin or matching placebo on days 1 and 24. The primary end-point was the baseline-adjusted, placebo-corrected effect on the individually corrected QT interval (QTcI) on days 12 (after 5 days of 40 mg ponesimod) and 23 (after 5 days of 100 mg ponesimod). Ponesimod caused a mild QTcI prolongation with a largest effect of 6.9 ms (90% two-sided confidence interval (CI): 2.5-11.3) and 9.1 ms (90% CI: 4.1-14.0) for doses of 40 mg and 100 mg, respectively. A concentration-effect analysis confirmed the QTcI-prolonging effect of ponesimod with a shallow slope of 0.0053 ms per ng/mL. Using the concentration-effect analysis, the QTc prolongation caused by 20 mg ponesimod and the current highest therapeutic dose was predicted to be below the level of clinical concern (i.e. an upper bound of the two-sided 90% CI of ≥10 ms).

Safety, tolerability, and pharmacokinetic evaluation of single- and multiple-ascending doses of a novel kappa opioid receptor antagonist LY2456302 and drug interaction with ethanol in healthy subjects.

Accumulating evidence indicates that selective antagonism of kappa opioid receptors may provide therapeutic benefit in the treatment of major depressive disorder, anxiety disorders, and substance use disorders. LY2456302 is a high-affinity, selective kappa opioid antagonist that demonstrates >30-fold functional selectivity over mu and delta opioid receptors. The safety, tolerability, and pharmacokinetics (PK) of LY2456302 were investigated following single oral doses (2-60 mg), multiple oral doses (2, 10, and 35 mg), and when co-administered with ethanol. Plasma concentrations of LY2456302 were measured by liquid chromatography-tandem mass spectrometry method. Safety analyses were conducted on all enrolled subjects. LY2456302 doses were well-tolerated with no clinically significant findings. No safety concerns were seen on co-administration with ethanol. No evidence for an interaction between LY2456302 and ethanol on cognitive-motor performance was detected. LY2456302 displayed rapid oral absorption and a terminal half-life of approximately 30-40 hours. Plasma exposure of LY2456302 increased proportionally with increasing doses and reached steady state after 6-8 days of once-daily dosing. Steady-state PK of LY2456302 were not affected by coadministration of a single dose of ethanol. No clinically important changes in maximum concentration (Cmax ) or AUC of ethanol (in the presence of LY2456302) were observed.

Tirasemtiv amplifies skeletal muscle response to nerve activation in humans.

INTRODUCTION: In this study we tested the hypothesis that tirasemtiv, a selective fast skeletal muscle troponin activator that sensitizes the sarcomere to calcium, could amplify the response of muscle to neuromuscular input in humans. METHODS: Healthy men received tirasemtiv and placebo in a randomized, double-blind, 4-period, crossover design. The deep fibular nerve was stimulated transcutaneously to activate the tibialis anterior muscle and produce dorsiflexion of the foot. The force-frequency relationship of tibialis anterior dorsiflexion was assessed after dosing. RESULTS: Tirasemtiv increased force produced by the tibialis anterior in a dose-, concentration-, and frequency-dependent manner with the largest increases [up to 24.5% (SE 3.1), P < 0.0001] produced at subtetanic nerve stimulation frequencies (10 Hz). CONCLUSIONS: The data confirm that tirasemtiv amplifies the response of skeletal muscle to nerve input in humans. This outcome provides support for further studies of tirasemtiv as a potential therapy in conditions marked by diminished neuromuscular input.

Determining pharmacological selectivity of the kappa opioid receptor antagonist LY2456302 using pupillometry as a translational biomarker in rat and human.

BACKGROUND: Selective kappa opioid receptor antagonism is a promising experimental strategy for the treatment of depression. The kappa opioid receptor antagonist, LY2456302, exhibits ~30-fold higher affinity for kappa opioid receptors over mu opioid receptors, which is the next closest identified pharmacology. METHODS: Here, we determined kappa opioid receptor pharmacological selectivity of LY2456302 by assessing mu opioid receptor antagonism using translational pupillometry in rats and humans. RESULTS: In rats, morphine-induced mydriasis was completely blocked by the nonselective opioid receptor antagonist naloxone (3mg/kg, which produced 90% mu opioid receptor occupancy), while 100 and 300 mg/kg LY2456302 (which produced 56% and 87% mu opioid receptor occupancy, respectively) only partially blocked morphine-induced mydriasis. In humans, fentanyl-induced miosis was completely blocked by 50mg naltrexone, and LY2456302 dose-dependently blocked miosis at 25 and 60 mg (minimal-to-no blockade at 4-10mg). CONCLUSIONS: We demonstrate, for the first time, the use of translational pupillometry in the context of receptor occupancy to identify a clinical dose of LY2456302 achieving maximal kappa opioid receptor occupancy without evidence of significant mu receptor antagonism.

Multiple-dose pharmacokinetics and pharmacodynamics of sergliflozin etabonate, a novel inhibitor of glucose reabsorption, in healthy overweight and obese subjects: a randomized double-blind study.

Sergliflozin, the active entity of sergliflozin etabonate, is a selective inhibitor of the sodium-dependent glucose cotransporter-2 in the renal tubule. The pharmacokinetics and pharmacodynamics of sergliflozin were examined during administration of sergliflozin etabonate (500 or 1000 mg) or placebo 3 times daily (tid) for 14 days in healthy overweight or obese human volunteers (n = 18). At the doses tested, sergliflozin showed less than dose-proportional pharmacokinetic characteristics. Mean half-life of the active entity was approximately 2 hours; there was no evidence of drug accumulation. Sergliflozin etabonate produced rapid and sustained suppression of renal glucose reabsorption, resulting in a dose-related glucosuria, and a transient increase in urinary electrolyte and fluid loss; plasma glucose, insulin, and electrolyte levels were unchanged. Sergliflozin etabonate produced a rapid, dose-related reduction in body weight (mean changes of -0.09, -1.55, and -1.74 kg from baseline to day 15 with placebo, sergliflozin etabonate 500 mg, and sergliflozin etabonate 1000 mg, respectively), apparently through increased urinary calorie loss rather than through osmotic diuresis. Sergliflozin etabonate 500 or 1000 mg tid was generally well tolerated; no clinically significant adverse events were identified. Renal function (creatinine clearance) was not affected by sergliflozin etabonate, although urinary microalbumin, N-acetyl-beta-D-glucosaminidase, and beta(2)-microglobulin levels tended to increase.

A thorough QTc study to assess the effect of sitagliptin, a DPP4 inhibitor, on ventricular repolarization in healthy subjects.

A randomized, double-blind, placebo-controlled, 4-period crossover study was performed with a single oral dose of sitagliptin (100 mg, 800 mg), moxifloxacin (400 mg), and placebo in order to provide a rigorous assessment of the effect of sitagliptin on ventricular repolarization based on the ICH E14 guidance. The clinical dose of sitagliptin 100 mg was not associated with an increase in QTc interval, corrected using the Fridericia correction (QTcf), at any time point. The supratherapeutic 800-mg dose of sitagliptin was generally well tolerated and was associated with minimal, clinically insignificant prolongation of the QTcf interval at concentrations approximately 11-fold higher than maximal concentrations following the 100-mg clinical dose. The PK/QTc model demonstrated a shallow relationship between the plasma concentration of sitagliptin and the placebo-subtracted QTcf change from baseline, with a 0.59-millisecond increase in QTc for every 1000-nM increment in sitagliptin plasma concentration. The sensitivity of the assay to detect modest increases in QTc interval was established with the active control moxifloxacin. In conclusion, at clinically relevant concentrations, sitagliptin is not associated with clinically meaningful QTcf prolongation.

Metabolic disposition of [14C]bazedoxifene in healthy postmenopausal women.

Bazedoxifene is a selective estrogen receptor modulator under development for the prevention and treatment of osteoporosis. The disposition of [(14)C]bazedoxifene was determined in six healthy postmenopausal women after administration of a single oral dose of 20 mg (200 microCi). After dosing, blood was collected at frequent intervals, and urine and fecal samples were collected for up to 10 days. Aliquots of plasma, blood, urine, and fecal homogenates were analyzed for concentrations of radioactivity. Bazedoxifene metabolite profiles in plasma and feces were determined by high-performance liquid chromatography with radioactivity flow detection; metabolite structures were confirmed by liquid chromatography-mass spectrometry. Bazedoxifene was rapidly absorbed, exhibiting a mean peak plasma concentration of 3.43 ng/ml at 1.2 h postdose. The total mean recovery of the radioactive dose in excreta was 85.6%, with the majority recovered in feces (84.7%) and only a small fraction (0.81%) in urine. Radiochromatograms of plasma revealed that glucuronidation was the major metabolic pathway; little or no cytochrome P450-mediated metabolism was evident. The majority of circulating radioactivity was constituted by metabolites, with bazedoxifene-5-glucuronide being the predominant metabolite (up to 95%). Bazedoxifene-4'-glucuronide was a minor metabolite (up to 20%), and unchanged bazedoxifene represented 0 to 13% of the radioactivity in most plasma samples. Unchanged bazedoxifene was the major radioactive component in feces, however, reflecting unabsorbed drug and/or glucuronides that were hydrolyzed by intestinal bacterial enzymes. [(14)C]Bazedoxifene was generally well tolerated. These findings demonstrated that, after oral administration in healthy postmenopausal women, bazedoxifene was rapidly absorbed, metabolized via glucuronidation, and excreted predominantly in feces.

Effect of casopitant, a novel NK-1 antagonist, on the pharmacokinetics of dolasetron and granisetron.

OBJECTIVE: The objective of this study was to characterize the impact of casopitant, a novel neurokinin-1 receptor antagonist under investigation for the prevention of postoperative and chemotherapy-induced nausea and vomiting, on the pharmacokinetics of the commonly prescribed 5-hydroxytryptamine receptor 3 receptor antagonists, dolasetron or granisetron. MATERIALS AND METHODS: In a phase I, open-label, two-part, two-period, single-sequence study, two cohorts of healthy subjects received either oral dolasetron (100 mg once daily for 3 days) or oral granisetron (2 mg once daily for 3 days) alone (period 1) and combined with oral casopitant, 150 mg day 1, 50 mg days 2 and 3 (period 2). Pharmacokinetics of hydrodolasetron and granisetron were assessed on days 1 and 3 of each period. Log-transformed area under the curve (AUC) and Cmax were statistically analyzed by performing an analysis of variance. Eighteen subjects were enrolled in the dolasetron cohort; nine subjects were CYP2D6 extensive metabolizers (EMs) and nine subjects were CYP2D6 poor metabolizers. Nineteen subjects were enrolled in the granisetron cohort. RESULTS: The largest changes in hydrodolasetron exposure after coadministration with casopitant were seen in CYP2D6 EMs, with a 24% increase in hydrodolasetron AUC on day 1 and 30% increase in Cmax on days 1 and 3. All other changes in hydrodolasetron exposure were <20%, and granisetron exposure was not altered to any relevant extent (<11%). CONCLUSION: None of the changes observed are considered clinically meaningful, and coadministration of casopitant with dolasetron or granisetron was well tolerated.

Minimal pharmacokinetic interaction between the human immunodeficiency virus nonnucleoside reverse transcriptase inhibitor etravirine and the integrase inhibitor raltegravir in healthy subjects.

Etravirine, a next-generation nonnucleoside reverse transcriptase inhibitor, and raltegravir, an integrase strand transfer inhibitor, have separately demonstrated potent activity in treatment-experienced, human immunodeficiency virus (HIV)-infected patients. An open-label, sequential, three-period study with healthy, HIV-seronegative subjects was conducted to assess the two-way interaction between etravirine and raltegravir for potential coadministration to HIV-infected patients. In period 1, 19 subjects were administered 400 mg raltegravir every 12 h (q12 h) for 4 days, followed by a 4-day washout; in period 2, subjects were administered 200 mg etravirine q12 h for 8 days; and in period 3, subjects were coadministered 400 mg raltegravir and 200 mg etravirine q12 h for 4 days. There was no washout between periods 2 and 3. Doses were administered with a moderate-fat meal. Etravirine had only modest effects on the pharmacokinetics of raltegravir, while raltegravir had no clinically meaningful effect on the pharmacokinetics of etravirine. For raltegravir coadministered with etravirine relative to raltegravir alone, the geometric mean ratio (GMR) and 90% confidence interval (CI) were 0.90 and 0.68 to 1.18, respectively, for the area under the concentration curve from 0 to 12 h (AUC(0-12)), 0.89 and 0.68 to 1.15, respectively, for the maximum concentration of drug in serum (C(max)), and 0.66 and 0.34 to 1.26, respectively, for the trough drug concentration (C(12)); the GMR (90% CI) for etravirine coadministered with raltegravir relative to etravirine alone was 1.10 (1.03, 1.16) for AUC(0-12), 1.04 (0.97, 1.12) for C(max), and 1.17 (1.10, 1.26) for C(12). All drug-related adverse clinical experiences were mild and generally transient in nature. No grade 3 or 4 adverse experiences or discontinuations due to adverse experiences occurred. Coadministration of etravirine and raltegravir was generally well tolerated; the data suggest that no dose adjustment for either drug is necessary.

Effects of age, gender, and race/ethnicity on the pharmacokinetics of posaconazole in healthy volunteers.

Posaconazole is a triazole antifungal for prophylaxis of invasive fungal infection and treatment of oropharyngeal candidiasis. We evaluated the effects of gender, age, and race/ethnicity (black or white) on the steady-state pharmacokinetics of posaconazole in two studies on healthy adult subjects (>or=18 years of age). Additionally, we explored the effect of P-glycoprotein expression and MDR1 genotype on posaconazole pharmacokinetics in black and white subjects. Age, gender, and race/ethnicity had no clinically relevant effects on posaconazole pharmacokinetics. No association was observed between any MDR1 single-nucleotide polymorphism and the area under the concentration-time curve for posaconazole. Posaconazole was safe and well tolerated regardless of age, gender, or race/ethnicity. In conclusion, age, gender, and race/ethnicity have no clinically relevant effects on the steady-state pharmacokinetics of posaconazole in healthy adults; therefore, dosage adjustments based on these covariates are unnecessary.

Pharmacokinetics, metabolism and excretion of intravenous [l4C]-palonosetron in healthy human volunteers.

Palonosetron (Aloxi(R), Onicit(R)) is a potent, single stereoisomeric 5-HT(3) receptor antagonist developed to prevent chemotherapy-induced nausea and vomiting. The pharmacokinetics and metabolic disposition of a single intravenous [(14)C]-palonosetron (10 microg/kg, 0.8 microCi/kg) bolus dose were evaluated in six healthy volunteers (three males, three females) using serial blood, plasma, urine and fecal samples obtained over 10 days. The safety, tolerability and cardiac effects were assessed. Radiolabeled metabolic characterization revealed that unchanged palonosetron accounted for 71.9% of the total radioactivity in plasma over 96 h, with an extensive distribution volume (8.34 l/kg) and mean plasma elimination half-life of 37 h. Approximately 83% of the dose was recovered in urine ( approximately 40% as unchanged drug, with 50% metabolized; M9 and M4 were the major metabolites) and 3.4% in feces. Hydrolysis of urine samples suggests that the metabolites are not beta-glucuronide or sulfate conjugates of the parent drug or metabolites. The blood to plasma concentration ratio of the total radioactivity was 1.2, on average, indicating little selective partitioning in erythrocytes. Palonosetron was generally well tolerated; headache was the most frequently reported adverse event. Electrocardiograms and 72 h Holter monitoring revealed no clinically significant changes. Palonosetron circulates in plasma mainly as the parent drug. Renal elimination is the primary excretion route, with parent drug and metabolites M9 and M4 accounting for the majority of palonosetron disposition. These results indicate that both renal and hepatic routes are involved in the elimination of palonosetron from the body.

Parecoxib sodium demonstrates gastrointestinal safety comparable to placebo in healthy subjects.

BACKGROUND: The gastrointestinal safety of the novel injectable cyclooxygenase-2 selective inhibitor, parecoxib sodium, was compared with the nonselective nonsteroidal anti-inflammatory drug, ketorolac, and placebo in healthy subjects. STUDY: In a multicenter, randomized, double-blind, placebo-controlled design, 123 adults with endoscopically-confirmed normal upper gastrointestinal mucosae received parecoxib sodium 40 mg twice daily (7 days); placebo (2 days) followed by ketorolac 30 mg 4 times daily (5 days); or placebo (7 days) (each group n = 41). Posttreatment endoscopy scores were analyzed at 3 levels of severity: ulcers (scores of 7), > or =11 erosions/ulcers (scores of 5-7), and any erosions/ulcers (scores of 3-7). RESULTS: No subjects treated with parecoxib sodium or placebo developed gastroduodenal ulcers or > or =11 erosions/ulcers. Parecoxib sodium was comparable to placebo with respect to the combined incidence of erosions/ulcers (12% vs. 7%, P = 0.419). In contrast, in the ketorolac group, 11 (28%) subjects developed ulcers, 19 (48%) subjects developed > or =11 gastroduodenal erosions/ulcers, and the rate of combined ulcers/erosions was 85% (P < 0.001 vs. placebo and parecoxib sodium). CONCLUSIONS: Parecoxib sodium 40 mg twice daily for 7 days has a gastrointestinal safety profile superior to ketorolac 30 mg 4 times daily for 5 days, and comparable to placebo.