Single-Dose Pharmacokinetic Properties,Bioavailability, and Tolerability of Two Lamivudine 100-mg Tablet Formulations: A Randomized Crossover Study in Healthy Chinese Male Subjects

Background

Lamivudine is used in the treatment of HIV and chronic hepatitis B (HBV) infections. Since 1999, at least 2 million Chinese HBV patients have been treated with lamivudine, but there are limited studies on the pharmacokinetics and safety of the drug in Chinese populations.

Objective

This study was designed to assess the bioequivalence of a newly developed lamivudine tablet (test drug) and a branded lamivudine tablet (reference drug) in healthy Chinese male volunteers.

Methods

A single-center, single-dose, randomized, open-label, 2-period crossover study was conducted in 28 healthy Chinese male volunteers. Blood samples were collected up to 24 hours after the administration of oral lamivudine 100 mg in each period. Plasma lamivudine concentrations were analyzed by a validated LC–MS/MS method. Pharmacokinetic and bioavailability parameters were calculated. Adverse events (AEs) were recorded.

Results

There were no significant differences in mean (SD) pharmacokinetic parameters between the test and reference drugs, including C_max (1239 [328.9] ng/mL vs 1176 [341.5] ng/mL), AUC_0–t (4096 [599.1] ng · h/mL vs 4064 [678.2] ng · h/mL), and AUC_0–∞ (4200 [607.7] ng · h/mL vs 4162 [672.2] ng · h/mL). The geometric mean test/reference ratios (90% CI) calculated for the log-transformed parameters were C_max, 1.06 (96.21–116.90); AUC_0–t, 1.01 (96.53–105.39); and AUC_0–∞, 1.01 (96.81–105.16), all of which were within the acceptance limits for bioequivalence. No serious AEs were reported, and all mild AEs were recovered quickly without treatment.

Conclusion

These findings suggest that the test formulation of lamivudine 100 mg meets the FDA regulatory standards for bioequivalence with the reference formulation. Both formulations were well tolerated.     

Comparative Fasting Bioavailability of 2 Bepotastine Formulations in Healthy Male Chinese Volunteers: An Open-Label,Randomized, Single-Dose, 2-Way Crossover Study

Background

Bepotastine is a second-generation histamine₁ receptor antagonist that is used in the treatment of allergic rhinitis, urticaria, and pruritus associated with skin disease. A new generic formulation of bepotastine has been developed in China, and information concerning bioavailability and pharmacokinetic properties in the Chinese population has not been reported.

Objective

The aim of the present study was to compare the bioavailability and pharmacokinetic properties of 2 tablet formulations of bepotastine, the 10-mg generic formulation (test) and a branded formulation (reference), in healthy male Chinese volunteers to obtain registration approval of the test formulation.

Methods

A single-center, open-label, randomized, 2-way crossover study with a 1-week washout period was conducted in 24 healthy male volunteers. Blood samples were collected for 16 hours after a single dose of the 10-mg bepotastine test formulation or the reference formulation. Plasma bepotastine concentrations were determined using a validated LC-MS/MS method. C_max, T_max, AUC_0–t, AUC_0–∞, and t_½ were determined using noncompartmental analysis. The formulations were considered bioequivalent if the 90% CIs for the log-transformed C_max and AUC values were within the predetermined interval of 75% to 133% and 80% to 125%, respectively, according to the guidelines of the China Food and Drug Administration.

Results

No significant differences were found in mean (SD) pharmacokinetic parameters between the test and reference drugs, including C_max (74.81 [9.91] ng/mL vs 78.60 [29.58] ng/mL), AUC_0–t (295.55[115.29] ng·h/mL vs 299.17[109.29] ng·h/mL), and AUC_0-∞ (305.28 [118.50] ng·h/mL vs 310.90 [112.20] ng·h/mL). The mean (SD) t_½ values of the test and reference formulations were 2.53 (0.50) hours and 2.62 (0.41) hours, respectively. The 90% CIs of the treatment ratios for the logarithmic transformed values of C_max, AUC_0–t, and AUC_0–∞ were 86.96% to 101.80%, 93.22% to 104.13%, and 92.66% to 103.30%, respectively. All values were within the predetermined bioequivalence range. Two adverse events were reported as neutropenia (1 volunteer [4.2%]) and neutrophilia (1 volunteer [4.2%]). Both adverse events were transient and considered mild by physicians.

Conclusion

The test and reference tablets met the regulatory criteria for bioequivalence as defined by the China Food and Drug Administration. Both formulations were well tolerated. Chinese Clinical Trials Registry identifier: ChiCTR-TTRCC-13003723.     

The Effect of Ticagrelor on the Metabolism of Midazolam in Healthy Volunteers

Background

In vitro studies have demonstrated that ticagrelor, an oral antiplatelet agent, is a substrate, activator, and inhibitor of cytochrome P450 (CYP) 3A. Thus, potential CYP3A-mediated drug–drug interactions may occur.

Objectives

The goal of this article was to report study results on the effect of ticagrelor on the pharmacokinetics of oral midazolam (oral midazolam study) and oral versus intravenous (IV) midazolam (oral/IV midazolam study). Secondary objectives included assessing the effect of midazolam on ticagrelor pharmacokinetic parameters, and the safety and tolerability of ticagrelor/midazolam coadministration.

Methods

Two randomized crossover studies were conducted in healthy volunteers (n = 28 in each) with ticagrelor and midazolam. In the first study, volunteers received oral ticagrelor (400 mg daily) or placebo for 6 days, then oral midazolam (7.5 mg). The second study regimen was a single dose of ticagrelor 270 mg, then ticagrelor 180 mg BID for 6 days with a single oral (7.5 mg) or IV (2.5 mg) dose of midazolam.

Results

After oral midazolam administration, ticagrelor significantly reduced the AUC_0–∞ of midazolam (30%–32%) and 4-hydroxymidazolam (42%–47%) but not 1-hydroxymidazolam. After administration of IV midazolam, ticagrelor reduced the AUC_0–∞ of midazolam (12%) and 4-hydroxymidazolam (23%) but not 1-hydroxymidazolam.

Conclusions

These results indicate that ticagrelor can weakly activate the metabolism of midazolam to its major 1′-hydroxy metabolite, and at the same time, seems to weakly inhibit midazolam 4′-hydroxylation. Furthermore, ticagrelor affects both hepatic and intestinal CYP3A activity.     

Single-Dose,Randomized Crossover Comparisons of Different-Strength Imatinib Mesylate Formulations in Healthy Korean Male Subjects

Background

Imatinib mesylate is used to treat chronic myeloid leukemia and advanced gastrointestinal stromal tumors.

Objective

The purpose of this study was to compare the pharmacokinetics of 2 different strengths of the imatinib formulation containing 100 mg (reference) and 400 mg (test) to satisfy the regulatory requirement for marketing.

Methods

A single-center, randomized, single-dose, open-label, 2-period, 2-sequence, comparative crossover study with a 14-day washout period was conducted in 30 healthy male volunteers. Plasma samples for the drug analysis were collected up to 72 hours after drug treatment. Participants received either the reference (4 tablets of 100-mg imatinib) or the test (1 tablet of 400-mg imatinib) formulation during the first period and the alternative formulation during the second period. The safety profiles and tolerability of the 2 formulations were also assessed based on physical examinations, laboratory tests, a 12-lead ECG, and vital signs.

Results

Thirty participants were initially enrolled; their mean (SD) age, height, weight, and body mass index were 24.9 (2.0) years (range, 23–30 years), 174 (5) cm (range, 164–185 cm), 69.9 (2.0) kg (range, 54.1–87.4 kg), and 23.0 (2.0) kg/m² (range, 18.5–26.9 kg/m²); 28 healthy participants completed both treatment periods. Two subjects did not complete the study because they withdrew consent for personal reasons. The observed mean (SD) C_max, AUC_0–last, and AUC_0–∞ values for the reference formulation were 1792 (357) ng/mL, 28,485 (6274) ng · h/mL, and 29,079 (6371) ng · h/mL, respectively. Corresponding values for the test formulation were 1710 (312) ng/mL, 27,222 (4624) ng · h/mL , and 27,872 (4751) ng · h/mL. The geometric mean ratios (90% CIs) between the 2 formulations at the 400-mg dose of imatinib were 0.9579 (0.9054–1.0136) for C_max, 0.9652 (0.9174–1.0155) for AUC_0–last, and 0.9679 (0.9203–1.0179) for AUC_0–∞, respectively. During the study period, 6 adverse events (3 for the reference and 3 for the test formulation) were reported; all were transient, mild, and resolved completely during the treatment period. There were 4 cases of nausea and 1 case each of dizziness and oropharyngeal pain. Four adverse events were considered related to the study drugs.

Conclusions

The results showed that despite the different strengths of the 2 imatinib formations, the test and reference formulations both met the regulatory criteria for pharmacokinetic equivalence at a dose of imatinib 400 mg in these healthy Korean male subjects. Both imatinib formulations seemed to be generally well tolerated. ClinicalTrials.gov identifier: NCT01270984.     

Effect of Ketoconazole on Lobeglitazone Pharmacokinetics in Korean Volunteers

Purpose

Lobeglitazone, a peroxisome proliferator–activated receptor-γ agonist, is metabolized primarily by the cytochrome P450 (CYP) 3A4 isoenzyme. Individuals concomitantly taking lobeglitazone and a CYP3A4 inhibitor may experience some adverse effects secondary to increased systemic exposure to lobeglitazone. To address such potential concern, we evaluated the effects of ketoconazole, a prototypic CYP3A4 inhibitor, on the pharmacokinetic (PK) properties and associated adverse effects of lobeglitazone.

Methods

A PK drug-drug interaction study was conducted in healthy individuals between 20 and 45 years old in a randomized, open-label, 2-way crossover design. Even though the PK study was performed on a single dose of lobeglitazone, multiple ketoconazole doses were given to ensure that the full extent of inhibition of CYP3A4 was maintained during the PK sampling. All study participants received a single oral dose of lobeglitazone 0.5 mg with or without 9 oral 200-mg doses of ketoconazole pretreatment twice daily. The primary PK parameter end points (AUC and C_max) were estimated using noncompartmental analysis, and the 90% CIs for the geometric mean ratios (ratio of lobeglitazone and ketoconazole to lobeglitazone alone) were investigated. Tolerability (adverse events, vital signs, ECG, and laboratory tests) was also assessed.

Findings

A total of 24 Korean men (mean age, 26 years; age range, 20-32 years; mean weight, 68 kg; weight range, 59-81 kg) completed the study and were evaluable for lobeglitazone PK properties and tolerability. The mean (SD) C_max values of lobeglitazone with and without ketoconazole were 49 (7) ng/mL and 48 (6) ng/mL at 1.5 and 1.0 hours after dosing, respectively. The mean (SD) AUC_∞ values were 532 (117) ng·h/mL and 405 (110) ng·h/mL, respectively. Although the C_max was not significantly affected, the geometric mean ratio for AUC_∞ was increased by a point estimate of 1.33 (90% CI, 1.23-1.44). A single oral administration of lobeglitazone 0.5 mg with or without ketoconazole pretreatment did not produce any clinically significant adverse effects on vital signs, 12-lead ECG profiles, or laboratory tests.

Implications

The administration of lobeglitazone, 0.5 mg alone or in combination with multiple doses of ketoconazole, was generally well tolerated. The systemic exposure of lobeglitazone was increased to a modest extent by pretreatment with 9 twice-daily doses of ketoconazole. Clinicaltrials.gov identifier: NCT01330563     

Effect of Gemfibrozil,Rifampicin, or Probenecid on the Pharmacokinetics of the SGLT2 Inhibitor Empagliflozin in Healthy Volunteers

Background

Empagliflozin is a potent, oral, selective inhibitor of sodium glucose cotransporter 2 in development for the treatment of type 2 diabetes mellitus.

Objective

The goal of these studies was to investigate potential drug–drug interactions between empagliflozin and gemfibrozil (an organic anion-transporting polypeptide 1B1 [OATP1B1]/1B3 and organic anion transporter 3 [OAT3] inhibitor), rifampicin (an OATP1B1/1B3 inhibitor), or probenecid (an OAT3 and uridine diphosphate glucuronosyltransferase inhibitor).

Methods

Two open-label, randomized, crossover studies were undertaken in healthy subjects. In the first study, 18 subjects received the following in 1 of 2 randomized treatment sequences: a single dose of empagliflozin 25 mg alone and gemfibrozil 600 mg BID for 5 days with a single dose of empagliflozin 25 mg on the third day. In the second study, 18 subjects received a single dose of empagliflozin 10 mg, a single dose of empagliflozin 10 mg coadministered with a single dose of rifampicin 600 mg, and probenecid 500 mg BID for 4 days with a single dose of empagliflozin 10 mg on the second day in 1 of 6 randomized treatment sequences.

Results

In the gemfibrozil study, 11 subjects were male, mean age was 35.1 years and mean body mass index (BMI) was 23.47 kg/m². In the rifampicin/probenecid study, 10 subjects were male, mean age was 32.7 years and mean BMI was 23.03 kg/m². Exposure to empagliflozin was increased by coadministration with gemfibrozil (AUC_0–∞: geometric mean ratio [GMR], 158.50% [90% CI, 151.77–165.53]; C_max: GMR, 115.00% [90% CI, 106.15–124.59]), rifampicin (AUC_0–∞: GMR, 135.20% [90% CI, 129.58–141.06]; C_max: GMR, 175.14% [90% CI, 160.14–191.56]), and probenecid (AUC_0–∞: GMR, 153.47% [90% CI, 146.41–160.88]; C_max: GMR, 125.60% [90% CI, 113.67–138.78]). All treatments were well tolerated.

Conclusions

Increases in empagliflozin exposure were <2-fold, indicating that the inhibition of the OATP1B1/1B3, OAT3 transporter, and uridine diphosphate glucuronosyltransferases did not have a clinically relevant effect on empagliflozin exposure. No dose adjustments of empagliflozin were necessary when it was coadministered with gemfibrozil, rifampicin, or probenecid. ClinicalTrials.gov identifiers: NCT01301742 and NCT01634100.     

Bioequivalence of Liposome-Entrapped Paclitaxel Easy-To-Use (LEP-ETU) Formulation and Paclitaxel in Polyethoxylated Castor Oil: A Randomized,Two-Period Crossover Study in Patients With Advanced Cancer

Background

Preclinical studies comparing paclitaxel formulated with polyethoxylated castor oil with the sonicated formulation of liposome-entrapped paclitaxel (LEP) have demonstrated that LEP was associated with reduced toxicity while maintaining similar efficacy. Preliminary studies on the pharmacokinetics in patients support earlier preclinical data, which suggested that the LEP Easy-to-Use (LEP-ETU) formulation and paclitaxel formulated with castor oil may have comparable pharmacokinetic properties.

Objectives

Our objectives were: (1) to determine bioequivalence of paclitaxel pharmaceutically formulated as LEP-ETU (test) and paclitaxel formulated with castor oil (reference); and (2) to assess the tolerability of LEP-ETU following intravenous administration.

Methods

Patients with advanced cancer were studied in a randomized, 2-period crossover bioequivalence study. Patients received paclitaxel 175 mg/m² administered as an intravenous infusion over 180 minutes, either as a single-treatment cycle of the test formulation followed by a single-treatment cycle of the reference formulation, or vice versa.

Results

Thirty-two of 58 patients were evaluable and were included in the analysis for bioequivalence. Mean total paclitaxel C_max values for the test and reference formulations were 4955.0 and 5108.8 ng/mL, respectively. Corresponding AUC_0-∞ values were 15,853.8 and 18,550.8 ng·h/mL, respectively. Treatment ratios of the geometric means were 97% (90% CI, 91%–103%) for C_max and 84% (90% CI, 80%–90%) for AUC_0-∞. These results met the required 80% to 125% bioequivalence criteria. The most frequently reported adverse events after LEP-ETU administration were fatigue, alopecia, and myalgia.

Conclusion

At the studied dose regimen, LEP-ETU showed bioequivalence with paclitaxel formulated with polyethoxylated castor oil.     

Pharmacokinetic Properties and Bioequivalence of 2 Formulations of Valsartan 160-mg Tablets: A Randomized,Single-Dose, 2-Period Crossover Study in Healthy Korean Male Volunteers

Background

The solubility of valsartan is dependent on pH and thus may cause patient variability in drug absorption and failure in bioequivalence studies; thus, increasing the solubility and release of valsartan at low pH has been suggested for a more favorable pharmacokinetic profile. However, due to this pH dependence, the change in the formulation process could alter the disintegration and/or dissolution profile of the drug, possibly making the results of bioequivalence studies misleading.

Objective

The aim of this study was to assess the bioavailability and tolerability of a newly developed oral formulation of valsartan 160 mg (wet-granulation tablet) in healthy Korean male volunteers.

Method

This study was performed with the subjects under fasted conditions, using a randomized, single-dose, 2-period crossover design. Subjects were assigned to receive, in randomized order, a single dose of the test formulation and a reference formulation (valsartan 160-mg dry-granulation tablet), with a washout period of 7 days between the administrations. Blood samples were collected up to 24 hours after dosing, and pharmacokinetic parameters were determined after the plasma valsartan concentration was analyzed using UPLC-MS/MS. The dissolution studies of both formulations were conducted using USP apparatus 2 at 50 rpm with 1000 mL of phosphate buffer solution (pH, 6.8) at 37°C ± 0.5°C. Bioequivalence was defined per Korean Food and Drug Administration’s regulatory criteria as 90% CIs of the geometric mean test/reference ratios of AUC_0–t and C_max within the range of 0.8 to 1.25. Tolerability was assessed using physical examination and subject interviews.

Results

Sixty subjects were enrolled (mean [SD] age [range], 23.6 [2.4] years [21–31]; height, 173.7 [6.6] cm [161–190]; and weight, 68.0 [8.7] kg [54–85]). The mean AUC_0–∞ values with the test and reference tablets were 31,784 (13,844) and 32,714 (14,512) ng·h/mL, respectively; C_max, 5094 (2061) and 5064 (1864) ng/mL; T_max, 2.92 (1.04) and 3.08 (1.01) hours. The 90% CIs for the geometric mean test/reference ratios of AUC_0–t and C_max were 0.9295 to 1.0546 and 0.9190 to 1.0848, respectively, which met the criteria for bioequivalence. The most frequently reported adverse event was dizziness after blank blood sampling, recorded in 4 subjects, 2 cases each with the test and reference formulations.

Conclusions

In this study in healthy Korean male volunteers, the test and reference formulations of 160-mg valsartan met the Korean Food and Drug Administration’s regulatory criteria for bioequivalence despite the difference in formulation (wet granulation vs dry granulation). Both formulations were well tolerated, with no serious adverse events reported.     

Maximal Cardiorespiratory Fitness Testing in Individuals With Chronic Stroke With Cognitive Impairment: Practice Test Effects and Test-Retest Reliability

Objectives

To evaluate, for individuals with chronic stroke with cognitive impairment, (1) the effects of a practice test on peak cardiorespiratory fitness test results; (2) cardiorespiratory fitness test-retest reliability; and (3) the relationship between individual practice test effects and cognitive impairment.

Design

Cross-sectional.

Setting

Rehabilitation center.

Participants

A convenience sample of 21 persons (men [n=12] and women [n=9]; age range, 48–81y; 44.9±36.2mo poststroke) with cognitive impairments who had sufficient lower limb function to perform the test.

Interventions

Not applicable.

Main Outcome Measure

Peak oxygen consumption (Vo₂peak, ml·kg⁻¹·min⁻¹).

Results

Test-retest reliability of Vo₂peak was excellent (intraclass correlation coefficient model 2,1 [ICC_2,1]=.94; 95% confidence interval [CI], .86–.98). A paired t test showed that there was no significant difference for the group for Vo₂peak obtained from 2 symptom-limited cardiorespiratory fitness tests performed 1 week apart on a semirecumbent cycle ergometer (test 2–test 1 difference, −.32ml·kg⁻¹·min⁻¹; 95% CI, −.69 to 1.33ml·kg⁻¹·min⁻¹; P=.512). Individual test-retest differences in Vo₂peak were, however, positively related to general cognitive function as measured by the Mini-Mental State Examination (ρ=.485; P<.026).

Conclusions

Vo₂peak can be reliably measured in this group without a practice test. General cognitive function, however, may influence the effect of a practice test in that those with lower general cognitive function appear to respond differently to a practice test than those with higher cognitive function.     

Bioequivalence of Two Intravenous Formulations of Antithrombin III: A Two-Way Crossover Study in Healthy Korean Subjects

Background

Treatment with antithrombin (AT)-III is indicated for patients with sepsis or hereditary AT deficiency.

Objective

The purpose of this study was to compare the pharmacokinetic and pharmacodynamic characteristics of 2 AT-III formulations in healthy Korean volunteers to satisfy the regulatory requirements for bioequivalence for marketing purposes.

Methods

A single-center, single-dose, open-label, randomized, 2-period, 2-sequence crossover study was conducted in healthy Korean volunteers. Blood samples for the drug analysis were collected for up to 216 hours after drug administration. Participants received either the test or reference formulation of AT-III 100 U/kg IV for 20 minutes in the first period and the alternative formulation in the second period. Both the AT-III activity and antigen (Ag) were measured for the analysis of pharmacokinetic properties, and the prothrombin time and the activated partial thromboplastin time were assessed for the analysis of pharmacodynamic properties. Because AT-III is an endogenous compound, the analysis used data corrected from baseline values. The tolerability of the 2 formulations was also assessed based on physical examinations including vital sign measurements, laboratory tests, and 12-lead ECG.

Results

Of the 20 subjects enrolled (mean [SD] age, height, and weight, 25.3 [2.3] years, 175.3 [4.5] cm, and 67.4 [6.3] kg, respectively), 19 completed both treatment periods; 1 subject withdrew consent for personal reasons. The observed mean (SD) C_max, AUC_last, and AUC_0–∞ of AT-III activity were, respectively, 279.24% (35.92), 14,364.10 (2325.25) %·h, and 17,526.38 (3150.81) %·h with the test formulation and 249.75% (31.96), 12,962.95 (1897.52) %·h, and 15,957.67 (3189.21) %·h with the reference formulation. The observed mean (SD) C_max, AUC_last, and AUC_0–∞ of AT-III Ag were 62.58 (5.66) mg/dL, 3051.94 (401.87) mg/dL·h, and 3639.80 (726.01) mg/dL·h, respectively, with the test formulation and 58.63 (5.27) mg/dL, 2805.08 (272.38) mg/dL·h, and 3340.00 (428.46) mg/dL·h with the reference formulation. The geometric mean ratios (90% CI) of the log-transformed data for AT-III activity between the 2 formulations were 1.11494 (1.08994–1.14053) for C_max, 1.11305 (1.05435–1.17503) for AUC_last, and 1.11527 (1.03754–1.19889) for AUC_0–∞; corresponding values for AT-III Ag were 1.08802 (1.06258–1.11405), 1.10905 (1.05804–1.16242), and 1.11460 (1.02058–1.21726). During the study period, 8 adverse events were reported, and all were transient, mild, and resolved completely during the treatment period.

Conclusion

The results of the present study showed that these 2 AT-III formulations met the regulatory criteria for pharmacokinetic bioequivalence with respect to AT-III activity and Ag in these healthy Korean subjects. ClinicalTrials.gov identifier: NCT00846274.     

Pharmacokinetics of Pilsicainide Hydrochloride for Injection in Healthy Chinese Volunteers: A Randomized,Parallel-Group,Open-Label,Single-Dose Study

Background

Pilsicainide hydrochloride is a class IC antiarrhythmic agent used for the treatment of supraventricular and ventricular arrhythmias and atrial fibrillation.

Objective

The objective of the present study was to determine the pharmacokinetics (PK) of a pilsicainide hydrochloride injection in healthy Chinese adults. The study was conducted to meet China State Food and Drug Administration requirements for the marketing of the new generic formulation of pilsicainide hydrochloride.

Methods

This Phase I, randomized, parallel-group, open-label, single-dose PK study was conducted in healthy Chinese volunteers. Subjects were randomized to receive a single dose of 0.25-, 0.50-, and 0.75-mg/kg pilsicainide hydrochloride with a 10-minute intravenous infusion. Serial blood and urine samples were collected up to 24 hours after dosing; drug concentrations in plasma and urine were then determined by using LC-MS/MS. The PK parameters of pilsicainide were calculated from the plasma concentration–time data according to noncompartmental methods. Safety profile was evaluated by monitoring adverse events, clinical laboratory parameters, and the results of 12-lead ECGs.

Results

Thirty healthy volunteers (mean [SD] age, 28.0 [4.95] years; weight, 59.3 [6.51] kg; height, 165.0 [7.25] cm; body mass index, 21.7 [1.94] kg/m²) were randomly divided into 3 groups, each consisting of 5 men and 5 women. After single-dose intravenous administration of 0.25, 0.50, and 0.75 mg/kg of pilsicainide hydrochloride, mean C_max was 0.34 (0.11), 0.54 (0.15), and 1.05 (0.19) μg/mL, respectively; AUC_0–24 was 0.76 (0.12), 1.61 (0.37), and 2.61 (0.46) h · μg/mL; and AUC_0–∞ was 0.79 (0.13), 1.71 (0.46), and 2.72 (0.50) h · μg/mL. The ranges for t_½z, CL, and V_z were 5.19 to 5.98 hours, 4.73 to 5.44 mL/min/kg, and 2.23 to 0.58 L/kg, respectively. The mean urinary recovery rate within 24 hours was 75.0% (12.0%), 65.0% (19.2%), and 66.4% (14.1%). Men and women had significantly different AUC_0–24 values in the 0.50-mg/kg dose group (P = 0.044), and V_z showed significant differences between men and women in all 3 dose groups (P = 0.001). According to ECG parameters, PR intervals were significantly prolonged after administration at all 3 doses (P = 0.034, P < 0.001, and P = 0.034); no significant changes were seen in QRS width, QTc interval, or other parameters.

Conclusions

Pilsicainide hydrochloride demonstrated linear PK, and the increase in the exposure of pilsicainide (AUC_0–24 and AUC_0–∞) was dose proportional after single doses of 0.25, 0.50, and 0.75 mg/kg. All 3 pilsicainide hydrochloride doses were well tolerated in these Chinese volunteers. ChiCTR-ONC-13003546.     

Pharmacokinetics and Pharmacodynamics of Subcutaneous Recombinant Parathyroid Hormone (1–84) in Patients With Hypoparathyroidism: An Open-Label,Single-Dose,Phase I Study

Background

Impaired mineral homeostasis affecting calcium, phosphate, and magnesium is a result of parathyroid hormone (PTH) deficiency in hypoparathyroidism. The current standard of treatment with active vitamin D and oral calcium does not control levels of these major minerals. Recombinant full-length human PTH 1–84 (rhPTH[1–84]) is being developed for the treatment of hypoparathyroidism.

Objective

The goal of this study was to investigate the pharmacokinetics and pharmacodynamics of a single subcutaneous injection of rhPTH(1–84) in patients with hypoparathyroidism.

Methods

This was an open-label, dose-escalating study of single subcutaneous administration of 50 µg and then 100 µg of rhPTH(1–84). Enrolled patients (age range, 25–85 years) had ≥12 months of diagnosed hypoparathyroidism defined according to biochemical evidence of hypocalcemia with concomitant low-serum intact PTH and were taking doses ≥1000 mg/d of oral calcium and ≥0.25 µg/d of active vitamin D (oral calcitriol). The patient’s prescribed dose of calcitriol was taken the day preceding but not on the day of or during the 24 hours after rhPTH(1–84) administration. Each patient received a single 50-µg rhPTH(1–84) dose, had at least a 7-day washout interval, and then received a single 100-µg rhPTH(1–84) dose. The following parameters were assessed: plasma PTH; serum and urine total calcium, magnesium, phosphate, and creatinine; and urine cyclic adenosine monophosphate.

Results

After administration of rhPTH(1–84) 50 µg (n = 6) and 100 µg (n = 7), the approximate t_½ was 2.5 to 3 hours. Plasma PTH levels increased rapidly, then declined gradually back to predose levels at ~12 hours. The median AUC was similar with calcitriol and rhPTH(1–84) for serum 1,25-dihydroxyvitamin D (calcitriol, 123–227 pg · h/mL; rhPTH[1–84], 101–276 pg · h/mL), calcium (calcitriol, 3.3–3.7 mg · h/dL; rhPTH[1–84], 3.3–7.6 mg · h/dL), and magnesium (calcitriol, 0.7–0.9 mg · h/dL; rhPTH[1–84], 1.3–2.8 mg · h/dL). In contrast, the median AUC for phosphate was strongly negative with rhPTH(1–84) (calcitriol, −1.0 to 0.8 mg · h/dL; rhPTH[1–84], −21.3 to −26.5 mg · h/dL). Compared with calcitriol, rhPTH(1–84) 50 µg reduced 24-hour calcium excretion and calcium-to-creatinine ratios by 12% and 23%, respectively, and rhPTH(1–84) 100 µg reduced them by 26% and 27%. There was little overall impact on urine magnesium levels. Compared with calcitriol, rhPTH(1–84) 50 µg increased urinary phosphate excretion and phosphate-to-creatinine ratios by 53% and 54%, respectively, and rhPTH(1–84) 100 µg increased them by 45% and 42%. Urine cyclic adenosine monophosphate–to–creatinine ratio increased with rhPTH(1–84) by 2.3-fold (50 µg) and 4.4-fold (100 µg) compared with calcitriol.

Conclusions

PTH replacement therapy with rhPTH(1–84) regulated mineral homeostasis of calcium, magnesium, phosphate, and vitamin D metabolism toward normal in these study patients with hypoparathyroidism.     

Persistence of Warfarin Therapy for Residents in Long-term Care Who Have Atrial Fibrillation

Background

Among long-term care (LTC) residents with atrial fibrillation (AF), the use of warfarin to prevent stroke has been shown to be suboptimal. For those who begin warfarin prophylaxis in LTC, persistence on this therapy has not been reported.

Objective

This study was conducted to estimate persistence on warfarin among LTC residents with AF.

Methods

A retrospective analysis was conducted by using data from an LTC database. Pharmacy dispensing data were used to track warfarin use in residents with a diagnosis of AF who were newly started on warfarin therapy. The main outcome measure was persistence of warfarin over the first year of therapy. Survival analysis included Kaplan-Meier plots and a multivariate Cox proportional hazards model to test the association of resident characteristics and conditions with warfarin discontinuation.

Results

A total of 148 residents new to warfarin therapy met all study inclusion criteria. Median age was 84 years; 69% were female. Median time to therapy discontinuation was 197 days (95% CI, 137–249) across all study residents. By 90 days after the initiation of therapy, 37% (95% CI, 28–47) of study residents had discontinued warfarin; by 1 year, 65% (54%–76%) had discontinued warfarin therapy. The multivariate Cox regression analysis found that the following factors were independently associated with discontinuation of warfarin therapy: age 65 to 74 years (hazard ratio [HR] = 3.01 [95% CI, 1.04–8.73]), female sex (HR = 0.45 [95% CI, 0.24–0.87]), Hispanic race/ethnicity (HR = 2.86 [95% CI, 1.30–6.26]), Midwest region (HR = 2.13 [95% CI, 1.02–4.48]), and Alzheimer disease or dementia (HR = 1.97 [95% CI, 1.05–3.68]).

Conclusions

Although clinical practice guidelines exist for the prevention of stroke in AF patients, persistence on warfarin therapy seems suboptimal in many LTC residents with AF.     

Effects of Kinesio Taping on Venous Symptoms,Bioelectrical Activity of the Gastrocnemius Muscle,Range of Ankle Motion,and Quality of Life in Postmenopausal Women With Chronic Venous Insufficiency: A Randomized Controlled Trial

Objective

To assess the efficacy of Kinesio taping (KT) on venous symptoms, quality of life, severity, pain, edema, range of ankle motion (ROAM), and peripheral muscle myoelectrical activity in lower limbs of postmenopausal women with mild chronic venous insufficiency (CVI).

Design

Double-blinded randomized controlled trial with concealed allocation.

Setting

Clinical setting.

Participants

Consecutive postmenopausal women (N=123; age range, 62–67y) with early-stage CVI. None of the participants withdrew because of adverse effects.

Intervention

Participants were randomly assigned to an experimental group for standardized KT application for external gastrocnemius (EG) and internal gastrocnemius (IG) muscle enhancement and ankle function correction or a placebo control group for sham KT application. Both interventions were performed 3 times a week during a 4-week period.

Main Outcome Measures

Venous symptoms, CVI severity, pain, leg volume, gastrocnemius electromyographic data, ROAM, and quality of life were recorded at baseline and after treatment.

Results

The experimental group evidenced significant improvements in pain distribution, venous claudication, swelling, heaviness, muscle cramps, pruritus, and CVI severity score (P≤.042). Both groups reported significant reductions in pain (experimental group: 95% confidence interval [CI], 1.6 to 2.1; control group: 95% CI, −0.2 to 0.3). There were no significant changes in either group in quality of life, leg volume, or ROAM. The experimental group showed significant improvements in root mean square signals (right leg: EG 95% CI, 2.99–5.84; IG 95% CI, 1.02–3.42; left leg: EG 95% CI, 3.00–6.25; IG 95% CI, 3.29–5.3) and peak maximum contraction (right leg: EG 95% CI, 4.8–22.7; IG 95% CI, 2.67–24.62; left leg: EG 95% CI, 2.37–20.44; IG 95% CI, 2.55–25.53), which were not changed in controls.

Conclusions

KT may reduce venous symptoms, pain, and their severity and enhance gastrocnemius muscle activity, but its effects on quality of life, edema, and ROAM remain uncertain. KT may have a placebo effect on venous pain.     

Changes in Gross Motor Function and Health-Related Quality of Life in Adults With Cerebral Palsy: An 8-Year Follow-Up Study

Objective

To describe changes in gross motor function and health-related quality of life (HRQOL) in adults with cerebral palsy (CP).

Design

An 8-year follow-up survey.

Setting

Participants who completed the baseline survey in 2003 were invited.

Participants

The sample of adults with CP (N=54; response rate=37%) included a “younger group” (group 1; n=31; age, 23–27y; 15 women) and an “older group” (group 2; n=23; age, 33–42y; 10 women).

Interventions

Not applicable.

Main Outcome Measures

The Gross Motor Function Classification System (GMFCS), Self-Rated Health (SRH), the Health Utility Index Mark III (HUI₃), and the Assessment of Quality of Life (AQoL).

Results

Eight years after the initial survey, 27% of the participants in the combined group had deteriorations on the GMFCS, 52% on the SRH, 44% on the HUI₃, and 25% on the AQoL. Members of group 1 reported stable scores as they made the transition to adulthood, while many of the group 2 members experienced declines, with relative risk of 1.47 (95% confidence interval [CI], 0.16–2.24) on the GMFCS, 1.36 (95% CI, 0.83–2.23) on the SRH, 1.19 (95% CI, 0.66–2.15) on the HUI₃, and 3.17 (95% CI, 1.12–9.00) on the AQoL.

Conclusions

Although much attention has focused on the transitions of persons with CP during their late teens and early 20s, this research found that deteriorations in the GMFCS levels and the HRQOL were most evident in adults in their late 20s and 30s. More detailed longitudinal studies are required to evaluate the longer-term health outcomes among persons with CP into their 30s and beyond.     

Setipiprant,a Selective Oral Antagonist of Human CRTH2: Relative Bioavailability of a Capsule and a Tablet Formulation in Healthy Female and Male Subjects

Background

CRTH2 is a prostaglandin D₂ receptor that plays an important role in allergic inflammation. Setipiprant is a potent CRTH2 antagonist under development for the treatment of allergic diseases.

Objective

The aim of this study was to evaluate the tolerability and pharmacokinetics of a single oral dose of a setipiprant capsule (reference) and a tablet formulation.

Methods

This was an open-label, 2-period, 2-way crossover, randomized study in which 20 healthy women and men (1:1 ratio) received either 2 250-mg capsules or a 500-mg tablet of setipiprant. Subjects were between 18 and 45 years old, with a body mass index of 18.0 to 28.0 kg/m². Differences in pharmacokinetics of setipiprant formulations were explored overall and by sex.

Results

All subjects completed the study. Both formulations were well tolerated, with headache the most frequently reported adverse event (25% of subjects), followed by flatulence (15%) and somnolence and fatigue (10%). The adverse event profile in men and women and between formulations was similar. The ratios of geometric means for C_max (0.94; 95% CI, 0.79–1.12) and AUC_0–∞ (1.01; 95% CI, 0.92–1.12) were mostly within the limits of 0.80 to 1.25. When corrected for weight, the differences observed between sexes, within each treatment, for C_max (capsules: 1.01; 95% CI, 0.71–1.44; tablet: 0.89; 95% CI, 0.62–1.26) and AUC_0–∞ (capsules: 1.12; 95% CI, 0.86–1.47; tablet: 0.96; 95% CI, 0.73–1.25) were minor.

Conclusion

Both the setipiprant formulations were well tolerated. Setipiprant pharmacokinetics were similar between formulations, overall, and between sexes. The new tablet formulation may constitute a valid alternative to the capsule formulation for later clinical development phases. ClinicalTrials.gov identifier: NCT01877629.     

The Pharmacokinetics and Safety of a Fixed-Dose Combination of Acetylsalicylic Acid and Clopidogrel Compared With the Concurrent Administration of Acetylsalicylic Acid and Clopidogrel in Healthy Subjects: A Randomized,Open-Label, 2-Sequence, 2-Period,Single-Dose Crossover Study

Background

Dual antiplatelet therapy with clopidogrel plus acetylsalicylic acid (ASA) is used for the treatment of acute coronary syndrome. A combined formulation of ASA and clopidogrel has been developed to provide dosing convenience and improve adherence.

Objective

This study was designed to compare the pharmacokinetic properties and safety profile of a fixed-dose combination formulation of ASA and clopidogrel with concurrent administration of each agent in healthy male Korean volunteers.

Methods

This single-dose, randomized, open-label, 2-period crossover study was conducted in 64 healthy Korean volunteers. Equal numbers of eligible participants were randomly assigned to receive either the fixed-dose combination of ASA 100 mg and clopidogrel 75 mg or the free combination of each agent followed by a 7-day washout period and then administration of the alternate formulation. Serial blood samples were collected immediately before and after dosing for 24 hours. The safety profile was evaluated by using adverse events (AEs), which were assessed by physical examination, vital signs, ECGs, clinical laboratory tests, and interviews. The 2 formulations were considered to be bioequivalent if the 90% CIs for the log-transformed C_max and AUC_0–last values were within the predetermined range of 0.8 to 1.25.

Results

Sixty-four volunteers (mean [SD] age, 27.51 [8.15] years; weight, 68.55 [7.86] kg; height, 173.80 [5.94] cm) were enrolled, and 63 completed the study. For ASA, the 90% CIs for the geometric mean ratios of C_max and AUC_0–last were 0.9483 to 1.1717 and 0.9946 to 1.1020, respectively. For salicylic acid, the 90% CIs were 0.9614 to 1.0396 for C_max and 0.9778 to 1.0163 for AUC_0–last. For clopidogrel, the 90% CIs were 0.9809 to 1.2562 for C_max and 0.9674 to 1.2073 for AUC_0–last. Six of the 20 AEs reported were drug related: decreased hemoglobin levels (n = 2), fever (n = 1), and headache (n = 1) with the test formulation and increased alanine aminotransferase levels (n = 1) and dyspepsia (n = 1) with the reference formulation. All of the drug-related AEs were transient and mild in severity.

Conclusions

The fixed-dose combination of ASA and clopidogrel 100 mg/75 mg did not meet the regulatory criteria for bioequivalence as defined by the Korea Food and Drug Administration. Both formulations were well tolerated in these healthy male Korean subjects. ClinicalTrials.gov Identifier: NCT01448330     

Comparison of Scaled-average,Population, and Individual Bioequivalence on 2 Tablets of Pitavastatin Calcium: A 3-Period,Reference-replicated,Crossover Study in Healthy Chinese Volunteers

Background

Pitavastatin, a fully synthetic β-hydroxy-β-methylglutaryl–coenzyme A reductase inhibitor, is potent for the treatment of primary hyperlipidemia and mixed dyslipidemia. Recently, the original product and some generic products of pitavastatin calcium have become available in China. However, the intrasubject variability and interchangeability of this newly developed generic product and the branded innovator product have rarely been investigated in the Chinese population.

Purpose

The aim of this study is to develop and compare the scaled-average, population, and individual bioequivalence (BE) of pitavastatin calcium tablets in healthy Chinese volunteers. This study will be used to allow for the interchangeability (switchability and prescribability) of the 2 products in clinical medication in China.

Methods

A single-dose, reference-replicated, 3-period crossover BE study was conducted in 36 healthy male volunteers. Plasma samples were collected before and after oral administration of 2-mg test or reference tablets. A LC-MS/MS method was used to determine the concentration of pitavastatin calcium. A noncompartmental method was used to investigate the pharmacokinetic parameters. The ANOVA and 90% CIs of ln(AUC_0–t) and ln(C_max) were used for statistical analysis of scaled-average BE. A nonparametric test (Wilcoxon signed rank test) was performed to T_max. The analyses of population BE and individual BE were used to assess the switchability and prescribability of the 2 products.

Findings

Thirty-six volunteers were enrolled in this clinical research; 33 volunteers completed the 3 treatment periods. The mean (SD) relative bioavailability calculated from the ratios (T/R) of AUC_0–t was 101.3% (19.7%). The mean ln(AUC_0–t) and ln(C_max) were 98.64 (90% CI, 93.44–104.13) and 98.68 (90% CI, 91.88–105.99) within previously stipulated ranges recommended by the US Food and Drug Administration and the China Food and Drug Administration (CFDA). The intrasubject %CVs of AUC_0–t and C_max were 12.0% and 18.0% for the reference tablet and 13.0% and 17.0% for the test tablet. No significant differences were found among T_max (0.742 ± 0.276, 0.674 ± 0.202, and 0.689 ± 0.226, respectively) for reference tablet 1, reference Supplemental Table II in the online version at 10.1016/j.clinthera.2014.06.21, and test tablet by a Wilcoxon test (P > 0.05). For ln(AUC_0–t) and ln(C_max), the statistical test-reference ratios were 99.13% and 98.95%, respectively. After inspecting the results for reference and mixed scaling, all the upper confidence limits were <0; therefore, population and individual BE were given.

Implications

In the healthy Chinese males, the generic and branded name tablets of pitavastatin calcium are bioequivalent at the rate and extent of absorption after a comparison of scaled-average, population, and individual BE and thus may be used interchangeably. Both the formulations are generally well tolerated. Chinese Clinical Trial identifier: ChiCTR-TTRCC-13003973.     

A Survey of the Prevalence of Cell Phones Capable of Receiving Health Information among Patients Presenting to an Urban Emergency Department

Background

Mobile devices have been shown to assist patients with comprehension of health information, yet sparse data exist on what mobile devices patients own and preferences for receiving health information.

Objectives

To determine the prevalence of mobile devices capable of receiving health information among patients/visitors presenting to an urban Emergency Department (ED).

Methods

A random sample of patients/visitors ≥18 years was surveyed. The primary outcome was prevalence of mobile devices capable of receiving health information among patient/visitor units presenting to the ED. Means and 95% confidence intervals were derived for continuous data; proportions with Fisher’s exact 95% confidence intervals were derived for categorical data. Institutional review board approval was received before study initiation.

Results

Surveyors approached 1307 subjects: 68% (885) were eligible; 70% (620) agreed to participate; 4 participants were excluded, leaving 70% (616) in the final sample. Of the 616 participants, 82% stated cell phone ownership (95% confidence interval [CI] 0.79–0.85). Among cell phone owners (n = 507), 90% had the device with them (95% CI 0.87–0.92) in the ED. Of these participants (n = 456), 77% had text messaging (95% CI 0.73–0.81), 51% had Internet (95% CI 0.47–0.56), 51% had e-mail (95% CI 0.46–0.56), 39% could download audio content (95% CI 0.34–0.43), and 35% could download videos (95% CI 0.31–0.40). Even among those having an annual income ≤$20,000, nearly 80% of persons owned cell phones.

Conclusions

Cell phones capable of receiving health information are prevalent among patients/visitors presenting to an urban ED.