Pharmacokinetic and Pharmacodynamic Properties of Single- and Multiple-Dose of Dapagliflozin,a Selective Inhibitor of SGLT2, in Healthy Chinese Subjects

Background

Dapagliflozin, a selective, orally active, renal sodium glucose cotransporter 2 (SGLT2) 2 inhibitor, is under investigation as a treatment of type 2 diabetes mellitus (T2DM). Dapagliflozin reduces hyperglycemia by inhibiting renal glucose reabsorption and dose-dependently increasing urinary glucose excretion, independent of insulin secretion or action.

Objectives

These studies assessed the single- and multiple-dose pharmacokinetic and pharmaco dynamic properties of dapagliflozin and its major inactive metabolite, dapagliflozin 3-O-glucuronide (D3OG), in healthy subjects residing in China.

Methods

In 2 identically designed, open-label, single- and multiple-dose studies (n = 14 for both studies), healthy Chinese subjects were administered oral dapagliflozin 5 or 10 mg. In both studies, subjects received a single dose on day 1 (single-dose administration period) followed by 6 once-daily doses on days 5 to 10 (multiple-dose administration period). Pharmacokinetic parameters (plasma and urinary dapagliflozin and D3OG), pharmacodynamic response (urinary glucose excretion), and tolerability were assessed.

Results

Fourteen subjects completed the dapagliflozin 5-mg study, and 13 completed the dapagliflozin 10-mg study. Baseline characteristics were balanced across the two studies: 9 versus 10 men; mean age, 27.1 versus 28.9 years; mean weight, 62.8 versus 62.2 kg; and mean body mass index, 23.0 versus 22.2 kg/m² in the dapagliflozin 5- and 10-mg studies, respectively. In both doses, dapagliflozin was rapidly absorbed (T_max, ≤1.5 h), accumulation (defined as the geometric mean ratio of AUC_τ at day 10 to AUC_τ at day 1) after multiple dosing was minimal (<1.13 fold), and elimination half-life was 10 to 12 h. D3OG showed a slightly longer median T_max (≤2 h) but a similar plasma concentration–time profile and half-life compared with dapagliflozin. The majority of D3OG (up to 69.7% of the dapagliflozin dose) was excreted in urine, while ≤1.9% of dapagliflozin was excreted unchanged in urine. Over a 24-hour period and at steady state (day 10), urinary glucose excretion values were 28.1 and 41.1 g with dapagliflozin 5 and 10 mg, respectively. Dapagliflozin was generally well tolerated; one dapagliflozin 10 mg–treated subject discontinued the study because of a serious adverse event (bronchitis) considered by the investigator as unrelated to dapagliflozin dosing.

Conclusions

Pharmacokinetic and pharmacodynamic characteristics following single- and multiple-dose dapagliflozin 5 and 10 mg oral administration in healthy Chinese subjects were as predicted from previous studies and were similar to findings observed in non-Chinese healthy subjects. Dapagliflozin dosing was well tolerated. The clinically recommended dapagliflozin dose of 10 mg once daily is expected to be appropriate in patients of Chinese ethnicity; results from an efficacy and tolerability study in Chinese patients with T2DM are awaited.     

Effects of Hydrochlorothiazide on the Pharmacokinetics,Pharmacodynamics, and Tolerability of Canagliflozin,a Sodium Glucose Co-transporter 2 Inhibitor,in Healthy Participants

Background

Many patients with type 2 diabetes mellitus (T2DM) also have hypertension, which is commonly treated with thiazide diuretics, including hydrochlorothiazide (HCTZ). Canagliflozin, a sodium glucose cotransporter 2 inhibitor developed for the treatment of T2DM, lowers plasma glucose by inhibiting renal glucose reabsorption, thereby increasing urinary glucose excretion and mild osmotic diuresis. Because patients with T2DM are likely to receive concurrent canagliflozin and HCTZ, potential interactions were evaluated.

Objective

This study evaluated the effects of HCTZ on the pharmacokinetic and pharmacodynamic properties and tolerability of canagliflozin in healthy participants.

Methods

This Phase I, single-center, open-label, fixed-sequence, 2-period study was conducted in healthy participants. During period 1, participants received canagliflozin 300 mg once daily for 7 days, followed by a 14-day washout period. During period 2, participants received HCTZ 25 mg once daily for 28 days, followed by canagliflozin 300 mg + HCTZ 25 mg once daily for 7 days. Blood samples were taken before and several times after administration on day 7 of period 1 and on days 28 and 35 of period 2 for canagliflozin and HCTZ pharmacokinetic analyses using LC-MS/MS. Blood and urine samples were collected for up to 24 hours after canagliflozin administration on day 1 of period 1 and day 35 of period 2 for pharmacodynamic glucose assessment. Tolerability was also evaluated.

Results

Thirty participants were enrolled (16 men, 14 women; all white; mean age, 43.7 years). Canagliflozin AUC during a dosing interval (T) at steady state (AUC_τ,ss) and C_max at steady state (C_max,ss) were increased when canagliflozin was coadministered with HCTZ, with geometric mean ratios (90% CI) of 1.12 (1.08–1.17) and 1.15 (1.06–1.25), respectively. AUC_τ,ss and C_max,ss for HCTZ were similar with and without canagliflozin coadministration. The 24-hour mean renal threshold for glucose and mean plasma glucose were comparable for canagliflozin alone and coadministered with HCTZ. The change in 24-hour urine volume from baseline was −0.1 L with canagliflozin alone and 0.4 L with HCTZ alone and with canagliflozin + HCTZ. The overall incidence of adverse events (AEs) was higher with canagliflozin + HCTZ (69%) than with canagliflozin (47%) or HCTZ (50%) alone; most AEs were of mild severity. Overall, minimal changes in serum electrolytes (eg, sodium, potassium) were observed after coadministration of canagliflozin + HCTZ compared with individual treatments.

Conclusions

Adding canagliflozin treatment to healthy participants on HCTZ treatment had no notable pharmacokinetic or pharmacodynamic effects; canagliflozin coadministered with HCTZ was generally well tolerated, with no unexpected tolerability concerns. ClinicalTrials.gov identifier: NCT01294631.     

Efficacy and Tolerability Exposure–Response Relationship of Retigabine (Ezogabine) Immediate-Release Tablets in Patients With Partial-Onset Seizures

Background

Retigabine (international nonproprietary name)/ezogabine (United States adopted name) is an antiepileptic drug (AED) that enhances KCNQ (K_v7) potassium channel activity.

Objectives

The aim of this study was to explore the relationship between retigabine/ezogabine systemic exposure and efficacy and adverse events (AEs) of retigabine/ezogabine from Phase III clinical trials.

Methods

Data were combined from Studies 301 and 302, which were both randomized, double-blind, placebo-controlled, multicenter, parallel-group studies with similar inclusion and exclusion criteria. All patients had partial-onset seizures and were receiving 1 to 3 concomitant AEDs. Systemic exposure was predicted for each patient as the average steady-state AUC_0–τ during the 12-week maintenance phase, based on a population pharmacokinetic model developed for retigabine/ezogabine. Efficacy end points included reduction in total partial-seizure frequency from baseline and probability of ≥50% reduction from baseline in seizure frequency. The probabilities of occurrence of 6 AEs were also evaluated.

Results

AUC_0–τ values increased linearly over the 600- to 1200-mg/d dose range. Over the entire AUC_0–τ range, the probability of efficacy was greater than that for any AE. The slopes of the exposure–response relationship for probability of dizziness and abnormal coordination were similar to that for efficacy, whereas the slopes for dysarthria, somnolence, tremor, and blurred vision were shallower, indicating that the probability of these events occurring was less affected than the probability of efficacy by increases in retigabine/ezogabine AUC_0–τ.

Conclusions

Based on the summary statistics of pharmacokinetic parameters, systemic exposure to retigabine/ezogabine increased linearly with dose (600–1200 mg/d). Population pharmacokinetics and pharmacodynamics showed that the probability of efficacy and AEs increased with increasing systemic retigabine/ezogabine exposure, and the probability of efficacy was higher than the probability of any of the AEs. The 35%–50% between-patient variability and overlap between retigabine/ezogabine dose levels in AUC_0-τ values indicate that, as with other AEDs, doses should be individually titrated based on a balance between efficacy and tolerability.     

Pharmacokinetics and Tolerability of Tenofovir Disoproxil Fumarate 300 mg Once Daily: An Open-Label,Single- and Multiple-Dose Study in Healthy Chinese Subjects

Background

Tenofovir disoproxil fumarate (TDF) has been approved worldwide for the treatment of adults with chronic hepatitis B and, in combination with other antiretroviral agents, HIV-1 infection. Although its use for the treatment of HIV has been approved by the Chinese State Food and Drug Administration, there are no data on the pharmacokinetic profile of TDF in Chinese individuals.

Objectives

This study aimed to investigate the pharmacokinetic properties and tolerability of TDF in healthy Chinese subjects.

Methods

This open-label, single- and multiple-dose study was conducted in healthy Chinese volunteers. Subjects received TDF 300 mg once daily, administered as a single dose (day 1) and multiple doses (days 4–10). Multiple plasma samples were collected over time, and the concentrations of TDF were determined using LC-MS/MS. Pharmacokinetic parameters were estimated using a noncompartmental model. Tolerability was determined using clinical evaluation and monitoring of adverse events (AEs).

Results

Fourteen volunteers were enrolled (7 men, 7 women; mean age, 24.6 years). TDF was rapidly absorbed; median T_max was 0.75 hour, and t_½ was ~21 hours with single dosing. The mean ratio of AUC_0–τ steady state/AUC_0–24 single dose was 1.55. The pharmacokinetic properties of TDF were consistent between the single dose and multiple doses, and between men and women. No serious AEs were reported, and there were no discontinuations due to AEs.

Conclusions

There was an accumulation of approximately 55% in tenofovir exposure in healthy Chinese between multiple dose and single dose. TDF exhibited a pharmacokinetic profile similar to that of healthy Western subjects in a historical comparison. TDF was generally well tolerated in these healthy Chinese subjects. ClinicalTrials.gov identifier: NCT01480622.     

Pharmacokinetic Interaction Between Rosuvastatin and Olmesartan: A Randomized,Open-label, 3-period,Multiple-dose Crossover Study in Healthy Korean Male Subjects

Purpose

Rosuvastatin has been widely used in combination with olmesartan for the treatment of dyslipidemia accompanied by hypertension. With no information currently available on the interaction between the 2 drugs, a pharmacokinetic study was conducted to investigate the influence of rosuvastatin on olmesartan and vice versa when the 2 drugs were coadministered. The purpose of this study was to investigate the pharmacokinetic profile of coadministration of the rosuvastatin 20-mg tablet and the olmesartan 40-mg tablet and the associated drug–drug interaction in healthy Korean male volunteers.

Methods

This was a randomized, open-label, 3-period, multiple-dose crossover study. Eligible subjects were aged 20 to 50 years and within 20% of their ideal body weight. After being randomly assigned to 6 groups of equal number, subjects received each of the following 3 formulations once a day for 7 consecutive days with an 8-day washout period between the formulations: rosuvastatin 20-mg tablet, olmesartan 40-mg tablet, and coadministration of the rosuvastatin 20-mg tablet and the olmesartan 40-mg tablet. Blood samples were collected up to 72 hours after dosing, and pharmacokinetic parameters were determined for rosuvastatin, its active metabolite (N-desmethyl rosuvastatin), and olmesartan. Adverse events were evaluated based on subject interviews and physical examinations.

Findings

Among the 36 enrolled subjects, 34 completed the study (mean [range] age, 28.6 [23–49] y; mean [range] weight, 66.4 [52.2–78.7] kg). The 90% CIs of the geometric mean ratios for the primary pharmacokinetic parameters for the coadministration of the 2 drugs to the mono-administration of each drug were 85.14% to 96.08% for AUC_τ and 81.41% to 97.48% for C_ss,max for rosuvastatin, and 77.55% to 89.48% for AUC_τ and 75.62% to 90.12% for C_ss,max for N-desmethyl rosuvastatin; those values were 95.61% to 102.57% for AUC_τ and 91.73% to 102.98% for C_ss,max for olmesartan. Dizziness was the most frequently noted adverse drug reaction, occurring in 1 subject receiving mono-administration of rosuvastatin, 1 subject receiving mono-administration of olmesartan, and 4 subjects receiving coadministration of rosuvastatin and olmesartan. All the adverse events were expected, and there was no significant difference in the incidence between the 2 formulations.

Implications

This study suggests that rosuvastatin and olmesartan did not significantly influence each other’s pharmacokinetics when coadministered. Although the pharmacokinetics of N-desmethyl rosuvastatin were influenced by olmesartan, such interactions were considered clinically insignificant. All 3 formulations were well tolerated, and no serious adverse events or drug reactions were noted.     

Pharmacokinetic Interaction Between Rosuvastatin and Telmisartan in Healthy Korean Male Volunteers: A Randomized,Open-label,Two-period,Crossover, Multiple-dose Study

Purpose

Rosuvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, and telmisartan, an angiotensin receptor blocker, are commonly prescribed in combination for the treatment of dyslipidemia accompanied by hypertension. However, the nature of the pharmacokinetic interaction between the 2 drugs is not clearly understood. The goal of the present study was to investigate the pharmacokinetic drug–drug interaction between rosuvastatin and telmisartan in a healthy Korean population.

Methods

This was a randomized, 2-part, open-label, 2-period, crossover, multiple-dose study, with each part composed of different subjects between the ages of 20 and 55 years. In part 1, each subject received rosuvastatin 20 mg with and without telmisartan 80 mg once daily for 6 consecutive days. In part 2, each subject received telmisartan 80 mg with and without rosuvastatin 20 mg once daily for 6 consecutive days. In both parts, there was a 16-day washout period between mono- and coadministration. Blood samples were collected up to 72 hours after the last dose. Adverse events (AEs) were evaluated through interviews and physical examinations.

Findings

In part 1, the 90% CIs of the geometric mean ratios for the primary pharmacokinetic parameters for coadministration of the 2 drugs to monoadministration of each drug were 1.0736–1.2932 for AUC_τ and 1.7442–2.3229 for C_max,ss for rosuvastatin and 0.9942–1.1594 for AUC_τ and 1.3593–1.7169 for C_max,ss for N-desmethyl rosuvastatin, whereas in part 2, the CIs were 1.0834–1.2672 for AUC_τ and 1.1534–1.5803 for C_max,ss for telmisartan. The most frequently noted AE was cough in part 1, which occurred in 2 subjects receiving the combination therapy, and oropharyngeal pain in part 2, which occurred in 3 subjects receiving the combination therapy. All reported AEs were mild or moderate, and there was no significant difference in incidence between the treatments.

Implications

These findings demonstrated that rosuvastatin and telmisartan mutually affected each other’s pharmacokinetics, suggesting a possibility of drug–drug interaction. However, based on dose–response characteristics of the 2 drugs and previous results from other interaction studies, the degree of drug interaction observed in this study was not regarded as clinically significant. All treatments were well tolerated, with no serious AEs observed. ClinicalTrials.gov identifier: NCT01992601.     

Pharmacokinetic Interactions Between Eperisone Hydrochloride and Aceclofenac: A Randomized,Open-Label,Crossover Study of Healthy Korean Men

Background

Eperisone hydrochloride, a centrally acting muscle relaxant, is a calcium antagonist that causes vasodilation and antispastic actions. Aceclofenac, an anti-inflammatory analgesic and antipyretic drug, has similar efficacy and improved gastrointestinal tolerance compared with other nonsteroidal anti-inflammatory drugs, such as diclofenac. Although eperisone hydrochloride and aceclofenac are frequently coadministered, no published studies have reported on the pharmacokinetic interactions between these 2 drugs.

Objective

The aim of this study was to investigate any pharmacokinetic interactions between eperisone hydrochloride and aceclofenac in healthy Korean men.

Methods

This was a randomized, open-label, crossover study. Each participant was randomly assigned to 1 of 6 treatment sequences and received eperisone hydrochloride (3 doses of 50 mg each), aceclofenac (2 doses of 100 mg each), or both as a single dose with a 7-day washout period between each dose. Blood samples were collected ≤24 hours after dosing, and plasma eperisone hydrochloride and aceclofenac concentrations were determined using validated LC/MS-MS. Pharmacokinetic analyses were conducted using noncompartmental methods. A safety profile was determined using the measurement of vital signs, ECG, and clinical laboratory tests.

Results

A total 24 of men were enrolled, and all completed the study. The geometric mean ratios (90% CIs) of the C_max and AUC_0-∞ values for eperisone were 1.18 (0.828–1.673) and 1.12 (0.836–1.507), respectively. The geometric mean ratios (90% CIs) of the C_max and AUC_0-∞ for aceclofenac were 0.93 (0.847–1.022) and 1.01 (0.979–1.036), respectively. A total of 7 adverse events were reported in 7 men. All adverse events were mild, and no significant differences were found between treatment groups.

Conclusion

No clinically significant pharmacokinetic differences exist between 150 mg eperisone hydrochloride and 200 mg aceclofenac when administrated as a monotherapy or in combination.     

Evaluation of the Pharmacokinetic Interaction Between Ticagrelor and Venlafaxine,a Cytochrome P-450 2D6 Substrate,in Healthy Subjects

Purpose

Ticagrelor is a reversibly binding P2Y₁₂ receptor antagonist used clinically for the prevention of atherothrombotic events in patients with acute coronary syndromes (ACS). Ticagrelor has been shown in vitro to be a weak inhibitor of cytochrome P-450 (CYP) 2D6, a clinically important enzyme for the metabolism of many drugs. This study assessed the effects of coadministration of ticagrelor on the pharmacokinetics of the CYP2D6 substrate venlafaxine. The impact of venlafaxine on ticagrelor pharmacokinetic parameters was also investigated.

Methods

Healthy subjects (N = 22) received a single 180-mg oral dose of ticagrelor on days 1 and 9 and oral doses of venlafaxine on day 4 (37.5 mg BID) and days 5 through 10 (75 mg BID). Plasma concentrations of ticagrelor, venlafaxine, and their metabolites (AR-C124910XX and O-desmethylvenlafaxine [ODV], respectively) were quantified for pharmacokinetic analyses. Safety and tolerability were assessed throughout the study.

Findings

Overall, 19 of 25 subjects were male; 14 were white, 10 were black, and 1 was Asian. Mean (SD) age was 26 (6) years, and mean (SD) body mass index was 24.3 (2.9) kg/m². Ticagrelor had no effect on overall exposure to venlafaxine, as assessed by the AUC_0–τ (geometric least squares mean ratio, 110.32 ng · h/mL [90% CI, 106.27–114.52]). Venlafaxine C_max was increased by 22% in the presence of ticagrelor (121.83 ng/mL [90% CI, 111.80–132.75]). ODV AUC_0–τ and C_max were unaffected by coadministration with ticagrelor (98.71 ng · h/mL [90% CI, 96.61–100.85] and 101.44 ng/mL [90% CI, 98.34–104.65], respectively). Venlafaxine had no effect on the C_max or AUC_0–∞ of ticagrelor (96.54 ng/mL [90% CI, 85.03–109.61] and 89.67 ng · h/mL [90% CI, 82.78–97.14]) or AR-C124910XX (106.39 ng/mL [90% CI, 96.10–117.78] and 106.32 ng · h/mL [90% CI, 97.28–116.21], respectively). Ticagrelor and venlafaxine were well tolerated whether given alone or in combination.

Implications

Ticagrelor had no clinically relevant effect on the plasma levels of venlafaxine and its CYP2D6-generated active metabolite, ODV. On the basis of these data, ticagrelor is not expected to affect CYP2D6-mediated drug metabolism to a clinically relevant extent. Venlafaxine had no effect on the pharmacokinetics of ticagrelor.     

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     

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.     

Comparison of Pharmacokinetics of Two Fenofibrate Tablet Formulations in Healthy Human Subjects

Background

Fenofibrate is a serum lipid-lowering agent used as an adjunct to diet in patients with hypercholesterolemia and hypertriglyceridemia. The new fenofibrate tablet formulation was developed as a pharmaceutical equivalent to the marketed tablet formulation containing 145 mg.

Objective

The objective of this study was to compare the pharmacokinetics and safety of 2 tablet formulations containing 145 mg of fenofibrate (CAS number 49562-28-9) in healthy human subjects.

Methods

The study was a randomized, 2-treatment, 3-period, 3-sequence, single-dose, 3-way crossover, partial replicate bioequivalence study in healthy human subjects under fasting conditions. Eligible subjects received each treatment in a crossover manner according to the randomization schedule. Replicate dosing was conducted for the reference formulation to determine its intrasubject variability. The predose blood sample was taken within 1 hour before dosing, and serial blood sampling was performed up to 72.0 hours’ postdose. The analysis of plasma samples for concentrations of fenofibric acid, the active metabolite of fenofibrate, was conducted by using a validated LC-MS/MS method. Bioequivalence was to be concluded if the 90% CIs as constructed were within the range of 80% to 125% for C_max, AUC_0–t, and AUC_0–∞ for fenofibric acid. Subjects were monitored for safety and tolerability throughout the study.

Results

15 healthy human subjects between 18 and 45 years of age and having body mass index between 18.5 and 30 kg/m² were recruited into the study. The 90% CIs for the test/reference mean ratios of the ln-transformed pharmacokinetic variables C_max, AUC_0–t, and AUC_0–∞ were within the conventional bioequivalence range of 80% to 125%. Both formulations were well tolerated after a single oral dose in these healthy male subjects.

Conclusions

Both fenofibrate tablet formulations demonstrated equivalent rates and extent of systemic absorption, and hence were considered bioequivalent.     

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.     

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.     

Safety,Tolerability, Pharmacokinetics,and Pharmacodynamics of Recombinant Human Parathyroid Hormone (1–34) in Healthy Chinese Subjects

Background

The recombinant human parathyroid hormone (1–34) (rhPTH[1-34]) teriparatide is the first anabolic agent approved by the US Food and Drug Administration for the treatment of osteoporosis in men and women. This study was conducted to provide support for marketing authorization of an agent biosimilar to teriparatide in China.

Objective

The main aim of the present study was to assess the safety, tolerability, pharmacokinetic, and pharmacodynamic parameters of rhPTH(1–34) after single and multiple subcutaneous doses in healthy Chinese subjects.

Methods

Two open-label, randomized, single-center, dose-escalation studies were performed. In study 1, subjects were randomized to receive a single dose of rhPTH(1–34) (10, 20, 30, 40, 50, or 60 μg) or a multiple dose of rhPTH(1–34) (10 and 20 μg once daily for 7 consecutive days) to determine the safety profile and tolerability, as reflected by the incidence, intensity, and seriousness of the observed adverse events. In study 2, a single dose of rhPTH(1–34) (10, 20, or 40 μg) and a multiple dose of rhPTH(1–34) (20 μg) were administrated subcutaneously to investigate the pharmacokinetic and pharmacodynamic parameters.

Results

Forty-two subjects completed study 1, and 30 subjects completed study 2. rhPTH(1–34) was well tolerated during the investigated single (10–60 μg) and multiple (10–20 μg once daily for 7 consecutive days) dose ranges. The most generally reported adverse events were erythema at the injection site and gastrointestinal reactions. After single and multiple subcutaneous administration of rhPTH(1–34), the drug was rapidly absorbed, with a T_max of 20 to 30 minutes, and rapidly cleared from the plasma, with a t_½ of 47.2 to 60.6 minutes. The mean C_max, AUC_0–t, and AUC_0–∞ increased in proportion to the doses, whereas the t_½, total clearance, and T_max values were independent of the administered dose. No significant differences in pharmacokinetic parameters were noted by sex except for T_max in the 10-μg and 20-μg single-dose groups. Compared with the baseline levels, no significant changes or dose-related significant effects were observed in serum calcium and phosphate levels.

Conclusions

All rhPTH(1–34) doses appeared to be well tolerated in the population studied. Linear pharmacokinetic characteristics were displayed in the dose range studied. Chinese ClinicalTrials.gov identifier: ChiCTR-ONC-12002874.     

Pharmacokinetics of Rosuvastatin/Olmesartan Fixed-Dose Combination: A Single-Dose,Randomized, Open-Label, 2-Period Crossover Study in Healthy Korean Subjects

Background

Rosuvastatin, a lipid-lowering agent, has been widely used with olmesartan, a long-acting angiotensin II receptor blocker, indicated for the treatment of dyslipidemia accompanied by hypertension. A fixed-dose combination (FDC) tablet of these 2 drugs was recently developed to enhance the dosing convenience and to increase patient compliance while yielding pharmacokinetic profiles comparable to coadministration of each drug as individual tablets.

Objective

The goal of present study was to compare the pharmacokinetic profiles of single-dose administration of an FDC tablet containing rosuvastatin/olmesartan 20/40 mg (test formulation) with coadministration of a rosuvastatin 20-mg tablet and a olmesartan 40-mg tablet (reference formulation) in healthy Korean male volunteers, for the purpose of determining bioequivalence.

Methods

This single-dose, randomized, open-label, 2-period crossover study enrolled subjects aged 20 to 50 years and within 20% of ideal body weight. Each subject received a single dose of the test and reference formulations orally in a fasted state, with a 7-day washout period between the administrations. Blood samples were collected up to 72 hours after dosing, and pharmacokinetic parameters were determined for rosuvastatin, its active metabolite (N-desmethyl rosuvastatin), and olmesartan. Bioequivalence was concluded if the 90% CIs of the geometric mean ratios for the primary pharmacokinetic parameters were within the predetermined range of 80% to 125%. Adverse events (AEs) were evaluated based on subject interviews and physical examinations.

Results

Among the 58 enrolled subjects, 54 completed the study. The 90% CIs of the geometric mean ratios of the primary pharmacokinetic parameters were as follows: rosuvastatin: AUC_last, 85.60% to 97.40% and C_max, 83.16% to 98.21%; N-desmethyl rosuvastatin: AUC_last, 82.08% to 93.45% and C_max, 79.23% to 93.41%; and olmesartan: AUC_last, 97.69% to 105.69% and C_max, 100.35% to 109.42%. The most frequently noted AE was headache, occurring in 3 and 6 patients with the test and reference formulations, respectively. All of the AEs were expected, and there was no significant difference in the prevalences of AEs between the 2 formulations.

Conclusions

The pharmacokinetic properties of the newly developed FDC tablet of rosuvastatin/olmesartan 20/40 mg suggest that it is bioequivalent to co-administration of each drug as individual tablets in these healthy Korean male subjects. The two formulations were well tolerated, with no serious AEs observed. ClinicalTrials.gov identifier: NCT01823900.     

Assessment of Tacrolimus Absorption From the Human Intestinal Tract: Open-Label,Randomized, 4-Way Crossover Study

Background

Tacrolimus is an established immunosuppressant used for the prevention and treatment of allograft rejection in solid organ transplantation. An immediate-release oral formulation of tacrolimus has been commercially available since 1994 that is administered orally BID. To improve the compliance and quality of life of transplant patients, a once-daily modified release (MR) formulation is an attractive option. However, to be successful, the drug of interest must be sufficiently well absorbed from the distal region of the gastrointestinal tract.

Objective

To facilitate the development of an MR formulation, we investigated the absorption of tacrolimus from different regions of the human gastrointestinal tract, proximal and distal small bowels, and ascending colon.

Methods

The study was performed as an open-label, randomized, 4-way crossover design in 6 healthy white male subjects. For each subject, 1 mg (2 mg/mL) of tacrolimus solution in polyethylene glycol 400 was administered to each location in the gastrointestinal tract via a site-specific radiolabeled delivery capsule, which can release tacrolimus solution at specific sites of the gastrointestinal tract. Real-time visualization of capsule location and tacrolimus release at each target site was performed by using γ-scintigraphy. Blood samples were collected to determine tacrolimus levels in the blood. The pharmacokinetic parameters C_max, T_max after the capsule activation, AUC_0–24, and mean residence time were determined from the concentration–time profiles.

Results

Ten healthy male subjects underwent dosing. Six subjects completed all 4 treatments. Three adverse events (mild headache [n = 1], small amount of blood in stool [n = 1], and mild syncopal episode [n = 1]) that were possibly study drug related were reported in 3 different subjects. Tacrolimus was absorbed from not only the small intestine but also from the colonic region of the gastrointestinal tract. Although AUC_0–24 values revealed some site-specific absorption tendencies, the mean AUC_0–24 values obtained were similar regardless of the location of tacrolimus release from the capsule.

Conclusions

Tacrolimus was absorbed from the duodenum to the colon in these male subjects, although differences were observed in the value of AUC_0–24, possibly due to variation in cytochrome P450 3A4 activity in the intestine. Although this study was conducted in small group of healthy fasting men, the present results indicate that tacrolimus is suitable for MR formulation development due to a wide absorption window throughout the intestine in humans.     

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.     

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.     

Race,Ethnicity, and Income Factors Impacting Human Papillomavirus Vaccination rates

Background

Human papillomavirus (HPV) infection and cervical cancer disproportionately affect low-income and minority women. HPV vaccines have the potential to either reduce or exacerbate racial disparities in HPV-related diseases and cervical cancers, depending on the equitability of vaccine uptake.

Objectives

This review aims to identify barriers and facilitators of equitable uptake of HPV vaccination among low-income and minority girls. This review discusses factors related to race, ethnicity, and income that are associated with initiation and completion rates of the 3-dose HPV vaccine series and presents targets for intervention.

Methods

We reviewed relevant English-language literature to identify current vaccination rates and factors associated with vaccine uptake. Study findings related to race (black, Latino, Asian), and incomes were summarized.

Results

Current trends in the United States indicate low uptake among all adolescents, and that rates stagnated between 2011 and 2012. Low-income and minority adolescents are equally or more likely to start the HPV vaccination series than are white and higher-income adolescents, but are less likely to complete all 3 shots. Provider recommendation is a key factor in HPV vaccination, and minorities are less likely to report receiving recommendations for HPV vaccination.

Conclusions

As black, Hispanic, and Asian populations continue to grow in the United States over the next several decades, it is imperative that we not only improve HPV vaccination rates overall, but also focus on high-risk populations to prevent an increase in cervical cancer disparities.