Maximum Observed Plasma Concentration Research Articles

Lack of effect of oral cabotegravir on the pharmacokinetics of a levonorgestrel/ethinyl oestradiol-containing oral contraceptive in healthy adult women.

AimsThis study aimed to investigate whether cabotegravir (CAB), an integrase inhibitor in development for treatment and prevention of human immunodeficiency virus‐1, influences the pharmacokinetics (PK) of a levonorgestrel (LNG) and ethinyl oestradiol (EO)–containing oral contraceptive (OC) in healthy women.MethodsIn this open‐label, fixed‐sequence crossover study, healthy female subjects received LNG 0.15 mg/EO 0.03 mg tablet once daily Days 1–10 alone and with oral CAB 30 mg once daily Days 11–21. At the end of each treatment period, subjects underwent predose sampling for concentrations of follicle‐stimulating hormone, luteinizing hormone, and progesterone and serial PK sampling for plasma LNG, EO, and CAB concentrations.ResultsTwenty women were enrolled, and 19 completed the study. One subject was withdrawn due to an adverse event unrelated to study medications. Geometric least squares mean ratios (90% confidence interval) of LNG + CAB vs. LNG alone for LNG area under the plasma concentration–time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.12 (1.07–1.18) and 1.05 (0.96–1.15), respectively. Geometric least squares mean ratio (90% confidence interval) of EO + CAB vs. EO alone for EO area under the plasma concentration–time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.02 (0.97–1.08) and 0.92 (0.83–1.03), respectively. Steady‐state CAB PK parameters were comparable to historical values. There was no apparent difference in mean luteinizing hormone, follicle‐stimulating hormone, and progesterone concentrations between periods. No clinically significant trends in laboratory values, vital signs, or electrocardiography values were observed.ConclusionsRepeat doses of oral CAB had no significant effect on LNG/EO PK or pharmacodynamics, which supports CAB coadministration with LNG/EO OCs in clinical practice.

Safety, Pharmacokinetics, and Pharmacodynamics Study in Healthy Subjects of Oral NEO6860, a Modality Selective Transient Receptor Potential Vanilloid Subtype 1 Antagonist

This first in human study on NEO6860, showed that an antagonist of TRPV1, blocking only the activation by capsaicin has been identified. This finding paves the way for the development of a new powerful analgesic for many pain conditions, without the fear of the side effects observed with previous TRPV1 antagonists.

Bioavailability of a dexlansoprazole delayed-release orally disintegrating tablet: effects of food and mode of administration.

BackgroundDexlansoprazole is a proton pump inhibitor (PPI) approved for use in dual delayed-release capsule and orally disintegrating tablet (ODT) formulations.AimTo assess effects of food, water, and route of administration on the bioavailability of dexlansoprazole 30-mg ODT.MethodsTwo separate open-label, phase 1, single-dose crossover studies were conducted in healthy adults. In study 1, pharmacokinetic parameters were analyzed in participants receiving dexlansoprazole ODT in a fed or fasted state with and without water. In study 2, the bioavailability of dexlansoprazole after administration via oral syringe or nasogastric (NG) tube, or after swallowing intact with water was compared to ODT administration in the fasted state, swallowed without water. Blood samples for determining dexlansoprazole plasma concentrations and pharmacokinetic parameter estimates were collected before and after dosing.ResultsEquivalent values for area under the plasma concentration–time curve (AUC) were observed in the fed and fasted states, but the maximum observed plasma concentration (Cmax) was 38% lower in the fed state; therefore, bioequivalence was not achieved. A water rinse following standard ODT administration decreased dexlansoprazole bioavailability, with lower Cmax and AUC values than when ODT was administered without a water rinse. Bioequivalence was demonstrated when comparing the alternative routes of administration, including via oral syringe or NG tube with standard ODT administration. Unlike with a water rinse, bioequivalence to standard ODT administration (i.e., without water) was demonstrated when swallowing the ODT intact with water. Rates of adverse events were comparable irrespective of administration route in the fasted state (6.7%–9.3%) and were 12% higher in the fed state than in the fasted state.ConclusionThe AUC from the dexlansoprazole ODT was equivalent when administered in the fed and fasted states. Equivalent systemic exposure to dexlansoprazole was achieved regardless of the administration route.

A phase 1 study of the pharmacokinetics of nucleoside analog trifluridine and thymidine phosphorylase inhibitor tipiracil (components of TAS-102) vs trifluridine alone

SummaryBackground Trifluridine, a thymidine-based chemotherapeutic, has limited bioavailability after clinical administration as it is rapidly degraded via thymidine phosphorylase. An oral combination tablet combines trifluridine with a potent thymidine phosphorylase inhibitor, tipiracil hydrochloride. This study’s objective was to evaluate whether trifluridine/tipiracil (TAS-102) administration increases trifluridine exposure vs trifluridine alone. Methods This open-label pharmacokinetic study randomly assigned patients with advanced solid tumors into two groups. On the morning of day 1, one group received a single 35 mg/m2 dose of trifluridine/tipiracil and the other group received a single 35-mg/m2 dose of trifluridine. Both groups received trifluridine/tipiracil 35 mg/m2 on the evening of day 1, then twice daily on days 2–5 and 8–12 in a 28-day cycle. Results Twenty patients received an initial one-time dose of trifluridine alone and 19 other patients received an initial dose of trifluridine/tipiracil. Trifluridine area under the curve (AUC0-last) and maximum observed plasma concentrations (Cmax) were approximately 37- and 22-fold higher, respectively, with trifluridine/tipiracil vs trifluridine alone. Plasma concentrations of the major metabolite of trifluridine were lower following the administration of trifluridine/tipiracil vs trifluridine alone. Conclusion Tipiracil administered in combination with trifluridine significantly increased exposure to trifluridine compared with trifluridine alone.

Pharmacokinetic and pharmacodynamic evaluation according to absorption differences in three formulations of ibuprofen.

ObjectiveProstaglandin E2 (PGE2) synthesis is modulated by COX2. Changes in PGE2 could be used to quantify the COX2 inhibition after ibuprofen administration. This study investigated the pharmacokinetic and pharmacodynamic relationships for COX2 inhibition according to three formulations of ibuprofen in healthy male subjects.Materials and methodsA randomized, open-label, single-dose, three-treatment, six-sequence crossover study was performed in 36 healthy South Korean male volunteers. Enrolled subjects received the following three 200 mg ibuprofen formulations: ibuprofen arginine, solubilized ibuprofen capsule, and standard ibuprofen. Pharmacokinetic and pharmacodynamic blood samples were collected for 16 hours following treatment. For pharmacodynamic evaluations, lipopolysaccharide (LPS)-induced PGE2 inhibition at each time point compared to predose was measured. Noncompartmental analysis was used for pharmacokinetic assessment, and time-weighted average inhibition (WAI) of PGE2 was applied to the pharmacodynamic evaluation.ResultsAfter a single oral dose of the ibuprofen formulations, the median times to maximum concentration were 0.42, 0.5, and 1.25 hours in ibuprofen arginine, solubilized ibuprofen capsule, and ibuprofen, respectively. The maximum observed plasma concentration was lower in ibuprofen, and the area under the plasma concentration–time curve was comparable among the three formulations. A significant difference was observed between fast-acting formulations and standard ibuprofen tablets for both maximum concentration and time taken to reach it. Individual formulations had an effect on PGE2 WAI during the 8 hours following treatment, resulting in significantly lower WAI in standard ibuprofen: ibuprofen arginine 18.4%, solubilized ibuprofen capsule 18.4%, and standard ibuprofen 11.6%.ConclusionRapid absorption and higher peak concentration were observed in ibuprofen arginine and the solubilized ibuprofen capsule. Additionally, fast-acting formulations had more predominant inhibitory activity on the COX2 enzyme.

Polarizing CD8+ Central Memory T Cells and Th1 Cells By Lenalidomide Contributes to the Antitumor Function of CD19 CAR-T Cells in Killing Diffused Large B Cell Lymphoma in Vitro

BackgroundCD19-CAR T cells with costimulatory ligand of CD28 or 4-1BB have acquired well response in ALL and CLL, whereas it shows less effective in B-cell NHL. The microenvironment of lymphomas is much more complicated than that of leukemia, which containing physical barriers and higher immunosuppression levels preventing lymphoma cells from T cell attack. To overcome such T cell toleration, one can optimize T cell fitness by adding co-stimulatory domain or polarizing T cell differentiation. Some pre-clinical studies have reported the 3rd generation of CD19-CAR T cells with CD28 and 4-1BB domain in treating ALL, but the results were in controversy. Lenalidomide has been proved to have direct anti-tumor effects in killing DLBCL cell lines except its immunomodulatory functions. Therefore, we did preliminary investigation in vitro to seek whether the combination of lenalidomide and CD19 CAR-T cells with both CD28 and 4-1BB costimulatory domain could acquire better effectsMethodWe first verified the proliferation inhibition of lenalidomide in treating both ABC-DLBCL cell lines (Su-DHL2 and OCI-Ly3) and GCB-DLBCL cell line OCI-Ly1. CY cell was primary cells isolated from GCB-DLBCL patients in Rui-jin Hospital. Under the maximum observed plasma concentration of lenalidmomide (2.2¦ÌM), the growth inhibition in both GCB-CY and OCI-Ly1 cell line was minimal, whereas the impact on ABC-DLBCL cell lines was more obvious. We further examined the efficiency of lenalidomide in vivo using a patient-derived mouse model. The primary lymphoma cells were obtained from a ABC-DLBCL patient and subcutaneously transplanted into NOD/SCID mouses. However, daily treated with lenalidomide could not delay the tumor growth (p>0.05) (Fig A, B, C). We next isolated CD3+ T cells from healthy donors, expanded with CD3/CD28 beads. The pLenti-EF1¦Á-CD19-28-BB-¦Æ-mcherry lentiviral vectors was generated and transduced in the expanded T cells to generate CD19 CAR-T cells. T cells transduced with pLenti-EFI¦Á-Actin-mcherry lentiviral vector were used as control. CD19-CAR T cells and T cells transdued with Actin-mcherry were pretreated with 2¦ÌM lenalidomide for 72 hours. LDH assay was then performed to identify the cytotoxicity of CD19-CAR T cells against CY in 7 hours. We found that lenalidomide substantially enhanced the anti-tumor function of CD19 CAR T cells and it also promoted the CD19-CAR T cells proliferation to some extent (Fig D, E). We therefore used three DLBCL patients CAR-T cells to identify the cytokine secretion. It was found that lenalidomide promoted Th1-biased cytokines secretion (IL-2, IFN-¦Ã, TNF-¦Á) and decreased Th2-biased cytokines (IL-6, IL-10). Interestingly, CAR-T cells secreted less IFN-¦Ã and TNF-¦Á but more IL-6 and IL-10 in killing OCI-Ly3 compared with OCI-Ly1 and CY (Fig F). The results leaded us to next determine the CD19-CAR T cell differentiation. A comparable increase of CD8+CD45RA-CD62L+ CD19 CAR T cells was observed as well as the CD4+CCR6-CCR4-CXCR3+ subset, indicating lenalidomide could induce CD19 CAR T cells differentiate to CD8+ central memory T cells and Th1 cells (Fig G). As the central memory T cells are more likely to home to the lymph nodes, we found that lenalidomide considerably increased the CD19-CAR T cell migration toward CCL21 and CCL19 in transwell system (Fig H).ConclusionIn conclusion, our results indicate that lenalidomide could polarize CD19-CAR T cells to CD8 TCM and Th1 subset, which might contribute to the enhanced antitumor function of CD19 CAR-T cells. Meanwhile, by overexpressed CD62L, lenalidomide could promote the migrating capability of CD19 CAR-T cells. More in-vivo work shall be done to determine the combination therapy in the future. [Display omitted] [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Pharmacokinetic Interactions between Tafenoquine and Dihydroartemisinin-Piperaquine or Artemether-Lumefantrine in Healthy Adult Subjects.

Tafenoquine is in development as a single-dose treatment for relapse prevention in individuals with Plasmodium vivax malaria. Tafenoquine must be coadministered with a blood schizonticide, either chloroquine or artemisinin-based combination therapy (ACT). This open-label, randomized, parallel-group study evaluated potential drug interactions between tafenoquine and two ACTs: dihydroartemisinin-piperaquine and artemether-lumefantrine. Healthy volunteers of either sex aged 18 to 65 years without glucose-6-phosphate dehydrogenase deficiency were randomized into five cohorts (n = 24 per cohort) to receive tafenoquine on day 1 (300 mg) plus once-daily dihydroartemisinin-piperaquine on days 1, 2, and 3 (120 mg/960 mg for 36 to <75 kg of body weight and 160 mg/1,280 mg for ≥75 to 100 kg of body weight), or plus artemether-lumefantrine (80 mg/480 mg) in two doses 8 h apart on day 1 and then twice daily on days 2 and 3, or each drug alone. The pharmacokinetic parameters of tafenoquine, piperaquine, lumefantrine, artemether, and dihydroartemisinin were determined by using noncompartmental methods. Point estimates and 90% confidence intervals were calculated for area under the concentration-time curve (AUC) and maximum observed plasma concentration (Cmax) comparisons of tafenoquine plus ACT versus tafenoquine or ACT. All subjects receiving dihydroartemisinin-piperaquine experienced QTc prolongation (a known risk with this drug), but tafenoquine coadministration had no clinically relevant additional effect. Tafenoquine coadministration had no clinically relevant effects on dihydroartemisinin, piperaquine, artemether, or lumefantrine pharmacokinetics. Dihydroartemisinin-piperaquine coadministration increased the tafenoquine Cmax by 38% (90% confidence interval, 25 to 52%), the AUC from time zero to infinity (AUC0–∞) by 12% (1 to 26%), and the half-life (t1/2) by 29% (19 to 40%), with no effect on the AUC from time zero to the time of the last nonzero concentration (AUC0–last). Artemether-lumefantrine coadministration had no effect on tafenoquine pharmacokinetics. Tafenoquine can be coadministered with dihydroartemisinin-piperaquine or artemether-lumefantrine without dose adjustment for any of these compounds. (This study has been registered at ClinicalTrials.gov under registration no. NCT02184637.)

Supratherapeutic dose evaluation and effect of lesinurad on cardiac repolarization: a thorough QT/QTc study.

IntroductionLesinurad is a selective uric acid reabsorption inhibitor approved in the United States and Europe for treatment of gout in combination with a xanthine oxidase inhibitor. A maximum tolerated dose study was conducted to determine the lesinurad supratherapeutic dose, followed by a thorough QTc study to characterize the effect of lesinurad on cardiac repolarization.MethodsThe maximum tolerated dose study was a randomized, double-blind, placebo-controlled, single-ascending dose study that enrolled 35 healthy men and women. Lesinurad plasma exposure (maximum observed plasma concentration and area under the plasma concentration versus time curve) was determined at doses of 800 mg, 1,200 mg, and 1,600 mg. The thorough QTc study was a double-blind, four-period, placebo-controlled crossover study with 54 healthy men and women who received single doses of lesinurad 1,600 mg (supratherapeutic dose), lesinurad 400 mg, moxifloxacin 400 mg, and placebo in randomized sequence. Digital 12-lead electrocardiograms were recorded at eleven time points over 24 hours in each treatment period. QT intervals were corrected for heart rate using an individual-specific correction factor (QTcI).ResultsThe upper bound of the one-sided 95% confidence interval for time-matched, placebo-subtracted, baseline-adjusted QTcI intervals (ΔΔQTcI) was <10 ms for both the lesinurad 400 mg and 1,600 mg doses. ΔΔQTcI was independent of lesinurad concentrations. No QTcI thresholds >480 ms or QTcI increases >30 ms were observed. Moxifloxacin mean QTcI intervals were >5 ms, and the lower bounds of the 90% confidence interval were >5 ms at 2 hours, 3 hours, and 4 hours, confirming assay sensitivity.ConclusionLesinurad, at supratherapeutic doses, does not have a significant effect on the QT interval in healthy male or female subjects.

Pharmacokinetic parameters for single- and multi-dose regimens for subcutaneous administration of a high-dose ceftiofur crystalline-free acid to neonatal foals.

The objective of this study was to determine the pharmacokinetics of single- and multi-dose ceftiofur crystalline-free acid (CCFA) administered subcutaneously at a dose of 13.2mg/kg to 12 neonatal foals 1-3days of age. Six foals received a single subcutaneous dose, while 6 additional foals received 4 doses of CCFA at 48-h intervals. Blood samples were collected at pre-determined times following drug administration, and plasma concentrations of ceftiofur free acid equivalents (CFAE) were measured using high-performance liquid chromatography. Following single-dose administration of CCFA, the mean±standard deviation maximum observed plasma concentration was 3.1±0.6μg/mL and observed time to maximal plasma concentration was 14.0±4.9h. Following multi-dose administration of CCFA, the mean±standard deviation times above CFAE concentrations of ≥0.5μg/mL and ≥2.0μg/mL were 192.95±15.86h and 78.80±15.31h, respectively. The mean±standard deviation area under the concentration vs time curve (AUC0→∝ ) was 246.2±30.7h×μg/mL and 172.7±27.14h×μg/mL following single- and multi-dose CCFA administrations, respectively. Subcutaneous administration of CCFA at 13.2mg/kg in neonatal foals was clinically well- tolerated and resulted in plasma concentrations sufficient for the treatment of most bacterial pathogens associated with neonatal foal septicemia. Multi-dose administration of four doses at dosing interval of 48h between treatments maintains appropriate therapeutic concentrations in neonatal foals.

Impact of Renal Impairment on the Pharmacokinetics of Apremilast and Metabolite M12.

The pharmacokinetics of apremilast and its major metabolite M12 were evaluated in subjects with varying degrees of renal impairment. Men and women with renal impairment (estimated glomerular filtration rate, 60‒89 mL/min [mild, n = 8], 30‒59 mL/min [moderate, n = 8], or <30 mL/min [severe, n = 8]) or demographically healthy matched (control) subjects (n = 24) received a single oral dose of apremilast 30 mg. Plasma apremilast and metabolite M12 concentrations were determined, and pharmacokinetic parameters were calculated from samples obtained predose and up to 72 hours postdose. In subjects with mild to moderate renal impairment, apremilast pharmacokinetic profiles were similar to healthy matched subjects. In subjects with severe renal impairment, apremilast elimination was significantly slower, and exposures based on area under the plasma concentration‐versus‐time curve from time zero extrapolated to infinity and maximum observed plasma concentration were increased versus healthy matched subjects. Metabolite M12 pharmacokinetic profiles for subjects with mild renal impairment were similar to those of the healthy matched subjects; however, they were increased in both the moderate and severe renally impaired subjects. Dose reduction of apremilast is recommended in individuals with severe renal impairment, but not in those with mild to moderate renal impairment.

RX-5902: A phosphorylated p68 targeting agent to treat subjects with advanced solid tumors.

TPS778 Background: Phosphorylated p68 may play a vital role in cell proliferation and tumor/cancer progression. RX-5902 is a novel compound that targets phosphorylated p68 RNA helicase (also known as DDX5), a member of the DEAD box family of RNA helicases. As a single agent, RX-5902 inhibits tumor growth and enhances survival in a variety of xenograft tumor models (e.g., pancreatic, renal, ovarian, melanoma). Methods: This Phase 1, open-label, multicenter study evaluates the efficacy and safety of RX-5902 in subjects with solid tumors. RX-5902 is administered orally 1, 3 or 5 times per week for 3 weeks with 1 week of rest in each 4 week cycle. Dose escalation starts with an accelerated design treating 1 subject per dose followed by a standard 3 + 3 design using a modified Fibonacci sequence after the occurrence of a single Grade 2 or greater adverse event that is considered at related to RX-5902. The primary endpoint is the overall safety profile characterized by the type, frequency, severity, timing of onset, duration and relationship to study therapy of any adverse events, or abnormalities of laboratory tests or electrocardiograms as well as the description of any dose limiting toxicities that occur during Cycle 1, serious adverse events, or adverse events leading to discontinuation of study treatment. Secondary endpoints include pharmacokinetic parameters (e.g., time to maximum observed concentration [Tmax], maximum observed plasma concentration [Cmax], trough concentration [Ctrough], area under the concentration-time curve [AUC]) and Indices of anti-tumor activity (e.g., overall response rate, time to response, duration of response, and progression-free survival during treatment. Exploratory endpoints are biochemical levels of drug targets in blood and tumor samples. Eligible subjects must have confirmed histologic or cytologic evidence of metastatic or locally advanced solid neoplasm that has failed to respond to standard therapy, progressed despite standard therapy or for which standard therapy does not exist. There is no limit on the number of prior treatment regimens. Clinical trial information: NCT02003092.

Pharmacokinetics of ertapenem in patients with multidrug-resistant tuberculosis.

Treatment of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) is becoming more challenging because of increased levels of drug resistance against second-line TB drugs. One promising group of antimicrobial drugs is carbapenems. Ertapenem is an attractive carbapenem for the treatment of MDR- and XDR-TB because its relatively long half-life enables once-daily dosing.A retrospective study was performed for all patients with suspected MDR-TB at the Tuberculosis Center Beatrixoord of the University Medical Center Groningen (Haren, the Netherlands) who received ertapenem as part of their treatment regimen between December 1, 2010 and March 1, 2013. Safety and pharmacokinetics were evaluated.18 patients were treated with 1000 mg ertapenem for a mean (range) of 77 (5-210) days. Sputum smear and culture were converted in all patients. Drug exposure was evaluated in 12 patients. The mean (range) area under the concentration-time curve up to 24 h was 544.9 (309-1130) h·mg·L(-1) The mean (range) maximum observed plasma concentration was 127.5 (73.9-277.9) mg·L(-1)In general, ertapenem treatment was well tolerated during MDR-TB treatment and showed a favourable pharmacokinetic/pharmacodynamic profile in MDR-TB patients. We conclude that ertapenem is a highly promising drug for the treatment of MDR-TB that warrants further investigation.

Synergism in Pharmacokinetics of Retagliptin and Metformin Observed during Clinical Trials of their Combination Therapy

Purpose: To investigate the safety and potential pharmacokinetic (PK) interaction between retagliptin, a selective inhibitor of dipeptidyl peptidase-4, and metformin in healthy subjects.Methods: In open-label, randomized, three-period, three-treatment crossover studies, 15 subjects received 100 mg retagliptin, 1500 mg metformin or the combination. The area under the curve from the time of dosing to infinity (AUCinf) and the maximum observed plasma concentration (Cmax) of each drug were measured.Results: The combination of retagliptin and metformin did not result in clinically significant alterations in the pharmacokinetics of SP2086 or metformin. The AUCinf and Cmax of retagliptin co-administered with metformin were 16.49 and 25.88 % higher than for retagliptin alone, respectively, while the AUCinf of metformin co-administered with retagliptin was 22.06 % higher than for metformin alone. The 90 % confidence interval of both glucose-lowering drugs’ AUCinf and Cmax of the geometric mean ratios of SP2086 + metformin fell within the pre-specified interval of 80 - 125 %. No laboratory adverse conditions occurred during the study. Retagliptin appeared generally safe and well-tolerated when administered alone or in combination with metformin.Conclusion: The results may be an indication that no dose adjustments are likely to be required when retagliptin is given in combination with metformin.

Pharmacokinetics, pharmacodynamics, and safety of USL261, a midazolam formulation optimized for intranasal delivery, in a randomized study with healthy volunteers

To compare the pharmacokinetics, pharmacodynamics, and tolerability of USL261, a midazolam formulation optimized for intranasal delivery, versus midazolam intravenous (IV) solution administered intranasally (MDZ-inj IN) or intravenously (MDZ-inj IV) in healthy adults. In this phase 1, five-way crossover, open-label study, 25 healthy adults (aged 18-42 years) were randomly assigned to receive 2.5, 5.0, and 7.5 mg USL261; 2.5 mg MDZ-inj IV; and 5.0 mg MDZ-inj IN. Blood samples were collected for 12 h post dose to determine pharmacokinetic profiles. Pharmacodynamic assessments of sedation and psychomotor impairment also were conducted. Adverse events, oxygen saturation, and vital signs were recorded. Increasing USL261 dose corresponded with increases in midazolam area under the concentration time curve (AUC) and maximum observed plasma concentration (Cmax ), with all doses demonstrating rapid median time to Cmax (Tmax ; 10-12 min). USL261 also demonstrated increased absorption, with a 134% relative bioavailability, compared with the same MDZ-inj IN dose. USL261 was associated with dose-dependent increases in sedation and psychomotor impairment (p < 0.05); however, these effects lasted <4 h and generally did not differ from MDZ-inj IN or MDZ-inj IV at comparable doses. No serious adverse events (SAEs) or deaths were reported, and no treatment-emergent adverse events (TEAEs) led to study discontinuation. Compared with intranasal delivery of a midazolam formulation intended for IV delivery, USL261, optimized for intranasal administration demonstrated improved bioavailability with similar pharmacodynamic effects. Therefore, USL261 may be a preferable alternative to the currently approved rectal diazepam treatment for intermittent bouts of increased seizure activity.

Single- and multiple-dose pharmacokinetics of biphasic immediate-release/extended-release hydrocodone bitartrate/acetaminophen (MNK-155) compared with immediate-release hydrocodone bitartrate/ibuprofen and immediate-release tramadol HCl/acetaminophen.

ObjectiveTo characterize the single-dose and steady-state pharmacokinetics (PK) of biphasic immediate-release/extended-release hydrocodone bitartrate/acetaminophen (IR/ER HB/APAP), IR HB/ibuprofen, and IR tramadol HCl/APAP.MethodsIn this single-center, open-label, randomized, four-period crossover study, healthy participants received four treatments under fasted conditions: 1) a single dose of two IR/ER HB/APAP 7.5/325 mg tablets (15/650 mg total dose) on day 1, followed by two tablets every 12 hours (q12h) beginning on day 3; 2) a single dose of IR HB/ibuprofen 15/400 mg (divided as one 7.5/200 mg tablet at hour 0 and 6), followed by one tablet every 6 hours (q6h) beginning on day 3; 3) a single dose of IR tramadol HCl/APAP 75/650 mg (divided as one 37.5/325 mg tablet at hour 0 and 6), followed by one tablet q6h beginning on day 3; and 4) a single dose of three IR/ER HB/APAP 7.5/325 mg tablets (22.5/975 mg total dose) on day 1, a three-tablet initial dose at 48 hours followed by two-tablet doses q12h beginning on day 3. Hydrocodone and APAP single-dose and steady-state PK were assessed. Adverse events were monitored.ResultsThe PK analysis was carried out on 29 of 48 enrolled participants who completed all treatment periods. Single-dose hydrocodone exposure was similar for IR/ER HB/APAP 22.5/975 mg and IR HB/ibuprofen 15/400 mg; time to maximum observed plasma concentration was shorter and half-life was longer for IR/ER HB/APAP (22.5/975 mg and 15/650 mg) vs IR HB/ibuprofen. Single-dose APAP exposure was similar for IR/ER HB/APAP 15/650 mg and IR tramadol HCl/APAP 75/650 mg. Steady-state hydrocodone and APAP exposures were similar between treatments. Adverse events were similar for each treatment and typical of low-dose combination opioid analgesics. With dosing q12h, IR/ER HB/APAP had half as many concentration peaks and troughs as the comparators treated q6h.ConclusionWith dosing q12h, IR/ER HB/APAP provided similar peak and total steady-state hydrocodone and APAP exposure vs IR comparators.

Pharmacokinetics and Safety of Single Intravenous Doses of JNJ-54452840, an Anti-β1-Adrenergic Receptor Antibody Cyclopeptide, in Healthy Male Japanese and Caucasian Participants.

To evaluate the pharmacokinetics and safety of single intravenous doses of JNJ-54452840 infused over 1 minute in healthy male Japanese and Caucasian participants. JNJ-54452840 is a novel peptide for the treatment of chronic heart failure, with a proposed mechanism of action of binding interference and decreased production of anti-β1-adrenergic receptor (anti-β1-AR) antibodies, which stimulate the cardiac β1-AR. In this randomized, single-centre, double-blind, placebo-controlled, four-way crossover study, 32 male Japanese and Caucasian participants (16 in each group) received single intravenous doses of JNJ-54452840 20, 80 and 240mg, and placebo, each separated by a≥7-day washout period. Pharmacokinetics and safety were assessed predose and at specified timepoints for 24h. Anti-β1-AR antibodies were monitored. The mean JNJ-54452840 maximum observed plasma concentration (C max) and area under the concentration-time curve from time zero to infinity with extrapolation of the terminal phase (AUCinf) values increased linearly with dose, with rapid elimination in both groups. Dose proportionality criteria were not met between the 20 and 240mg doses for both study cohorts. The median time to reach C max (T max) ranged from 1 to 5 minutes. The mean total systemic clearance after intravenous administration (CL), volume of distribution at steady state (V ss), mean residence time (MRT) and terminal half-life (T ½) values were similar for both groups. The mean T ½ values ranged from 5.9 to 26.1 min in a dose-dependent manner. The overall prevalence of antibodies was 9.4% at baseline; antibodies not present at baseline developed in five Caucasians (15.6%) but not in Japanese participants. One participant in each group experienced a serious thromboembolic event (pulmonary embolism, ischaemic stroke). JNJ-54452840 demonstrated similar pharmacokinetics in both groups. JNJ-54452840 was possibly immunogenic, and two participants reported thromboembolic serious adverse events. The relationship between these events and antibody formation is not known.

Single-Dose, Randomized, Open-Label, Two-Way, Crossover Bioequivalence Study of Two Formulations of Pregabalin 300 mg Hard Capsules in Healthy Volunteers Under Fasting Conditions.

AimsThis bioequivalence study was conducted to assess the bioequivalence of two formulations, test and reference, of pregabalin 300 mg hard capsules, under fasting conditions.MethodsThis was a single-center, randomized, single-dose, open-label, laboratory-blinded, two-way crossover study, with a minimum washout period of 7 days. Plasma samples were collected prior to and up to 36 h after dosing. Pregabalin plasma concentrations were determined, using a validated method, by reversed phase high performance liquid chromatography coupled to a tandem mass spectrometry detector (LC–MS–MS). Pharmacokinetic metrics used for bioequivalence assessment were the AUC(0–t) (area under the plasma concentration–time curve from time zero to time of last observed non-zero plasma concentration) and the Cmax (maximum observed plasma concentration). These parameters were determined from the pregabalin plasma concentration data using noncompartmental analysis.ResultsForty healthy subjects, age ranging from 18 to 43 years old, were enrolled and randomized, of whom 39 completed the study. The ratio of geometric least square means for Cmax was 99.29 % (90 % confidence interval [CI] 93.29–105.67). The ratio of geometric least square means for AUC(0–t) was 101.54 % (90 % CI 100.13–102.98). The 90 % CIs were within the predefined range (80.00–125.00).ConclusionsBioequivalence between test and reference formulations, under fasting conditions, was concluded both in terms of rate and extent of absorption.

Lack of the effect of lobeglitazone, a peroxisome proliferator-activated receptor-γ agonist, on the pharmacokinetics and pharmacodynamics of warfarin.

AimsLobeglitazone has been developed for the treatment of type 2 diabetes mellitus. This study was conducted to evaluate potential drug–drug interactions between lobeglitazone and warfarin, an anticoagulant with a narrow therapeutic index.MethodsIn this open-label, three-treatment, crossover study, 24 healthy male subjects were administered lobeglitazone (0.5 mg) for 1–12 days with warfarin (25 mg) on day 5 in one period. After a washout interval, subjects were administered warfarin (25 mg) alone in the other period. Pharmacokinetics of R- and S-warfarin and lobeglitazone, as well as pharmacodynamics of warfarin, as measured by international normalized ratio (INR) and factor VII activity, were assessed.ResultsThe geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for area under the curve from time zero to the time of the last quantifiable concentration (AUClast) for warfarin + lobeglitazone: warfarin alone were 1.0076 (90% CI: 0.9771, 1.0391) for R-warfarin and 0.9880 (90% CI: 0.9537, 1.0235) for S-warfarin. The maximum observed plasma concentration (Cmax) values were 1.0167 (90% CI: 0.9507, 1.0872) for R-warfarin and 1.0028 (90% CI: 0.9518, 1.0992) for S-warfarin, both of which were contained in the interval 0.80–1.25. Lobeglitazone had no effect on the area under the effect–time curve from time 0 to 168 hours (AUEC) of INR and factor VII activity, as demonstrated by the GMRs of 1.0091 (90% CI: 0.9872, 1.0314) and 0.9355 (90% CI: 0.9028, 0.9695), respectively. In addition, the pharmacokinetics of lobeglitazone was also unaffected by warfarin.ConclusionConcomitant administration of lobeglitazone and warfarin was well tolerated. Lobeglitazone had no meaningful effect on the pharmacokinetics or pharmacodynamics of warfarin. These findings indicate that lobeglitazone and warfarin can be coadministered without dosage adjustments for either drug.

Single- and multiple-dose pharmacokinetics and pharmacodynamics of canagliflozin, a selective inhibitor of sodium glucose co-transporter 2, in healthy participants.

To evaluate the pharmacokinetics of oral canagliflozin and its O-glucuronide metabolites (M7 and M5) after single and multiple doses in healthy adult participants. The pharmacodynamics, safety, and tolerability of canagliflozin were also evaluated. In this open-label, single- (day 1) and multiple-dose (days 4-9), parallel-group, phase 1 study, 27 healthy participants were randomized into three groups (1:1:1) to receive 50, 100, or 300 mg canagliflozin. Pharmacokinetics and pharmacodynamics were assessed at pre-pecified timepoints on days 1, 9, and 10. Mean area under the plasma concentration-time curve, and the maximum observed plasma concentration of canagliflozin, M7, and M5 increased in a dose-dependent manner, across all the 3 doses, following single- and multiple-dose administration. The mean apparent elimination half-lives of canagliflozin, M7, and M5 were independent of the dose. Canagliflozin decreased the renal threshold for glucose (RTG) and increased the urinary glucose excretion (UGE) in a concentration- and dose-dependent manner. The relationship between drug concentrations and RTG was described by a sigmoidal relationship with RTGmin (minimum value of RTG) of 37.5 ng/mL (95% confidence interval (CI): 34.3, 40.8) and half-maximal effective concentration (EC50) of 21 ng/mL (95% CI: 18.3, 23.8). No deaths, serious adverse events, hypoglycemic events, or discontinuations due to adverse events were observed. Pharmacokinetics of canagliflozin and its metabolites (M7 and M5) were linear, and no time-dependent changes were observed after single- and multiple-dose administration. Similarly, pharmacodynamic effects of canagliflozin on RTG and UGE were found to be dose- and concentration-dependent. Overall, canagliflozin was well-tolerated in healthy participants.

Cardiovascular safety pharmacology profile of etamicastat, a novel peripheral selective dopamine-ß-hydroxylase inhibitor

Etamicastat, a peripheral reversible dopamine-ß-hydroxylase inhibitor, blocked the hERG current amplitude with an IC50 value of 44.0µg/ml in HEK 293 cells. At 0.3 and 3µg/ml, etamicastat had no effects on the action potential (AP) in male dog Purkinje fibers. At 30µg/ml, etamicastat significantly affected resting membrane potential (+4%), AP amplitude (−4%), AP duration at 60% (−14%) and AP duration at 90% (+5%) repolarization, and AP triangulation (+79%). In the telemetered conscious male dog, etamicastat (up to 20mg/kg) had no effects on arterial blood pressure, heart rate and the PR interval. At 10 and 20mg/kg, the QTc interval was slightly prolonged (8–9% max, P<0.05). No arrhythmia or other changes in the morphology of the ECG were observed. The maximum observed plasma concentrations (Cmax) of etamicastat (i.e. 3h post-administration) were 1.4 and 3.7µg/ml at 10 and 20mg/kg, respectively. No deleterious effects, including ECG disturbance were observed in male and female dogs dosed by gavage with etamicastat (up to 20mg/kg/day) for 28 days. Mean plasma Cmax etamicastat levels ranged between 2.4 and 6.3µg/ml on Day 1 and Day 28 of treatment, respectively. It is concluded that the blockade of the delayed rectifier potassium channels by etamicastat together with the QTc interval prolongation observed in conscious dogs can be considered as modest with respect to the measured plasmatic concentrations. These findings suggest that etamicastat is not likely to prolong the QT interval at therapeutic doses (~0.2µg/ml).