Translational and Clinical Pharmacology最新文献

Analysis of a 2 × 2 table for clinical data involves computing the point estimate and confidence interval for risk difference, relative risk, or odds ratio. While point estimates of these comparative parameters are uniquely defined, several statistical methods have been proposed to estimate the confidence interval for each parameter. The Miettinen-Nurminen (MN) score method is expected to be used increasingly over traditional interval estimation methods. The MN score method has not been previously implemented in R software for data with stratification. There is a need for a comprehensive software implementation of the MN score method. This article describes the implementation of the MN score method in the sasLM R software package. To demonstrate the usage of the sasLM functions introduced, recently published clinical data are provided as examples.

In healthcare situations, time-to-event (TTE) data are common outcomes. A parametric approach is often employed to handle TTE data because it is possible to easily visualize different scenarios via simulation. Not all pharmacometricians are familiar with the use of non-linear mixed effects models (NONMEMs) to deal with TTE data. Therefore, this tutorial simply explains how to analyze TTE data using NONMEM. We show how to write the code and evaluate the model. We also provide an example of a hands-on model for training.

Fetal tachycardia (FT) is a rare disorder and is associated with significant mortality of fetus. Digoxin is one of the antiarrhythmic agents used to treat FT via transplacental therapy. In this report, we describe a therapeutic drug monitoring (TDM) case of digoxin during the treatment of FT. A 40-year-old woman, gravida 2 para 1, hospitalized to control FT as the fetal heart rate (FHR) showed over 200 bpm on ultrasonography at 29 weeks of gestation. She did not have any medical or medication history and showed normal electrolytes level on clinical laboratory test results. For the treatment of FT loading and maintenance dose of intravenous digoxin (loading dose: 0.6 mg; maintenance dose: 0.3 mg every 8 hours) were administered. To monitor the efficacy and safety of the treatment, TDM was conducted with a target maternal serum trough digoxin concentration of 1.0 to 2.0 ng/mL, as well as ultrasonography and maternal electrocardiogram. The observed digoxin serum concentrations were 0.67, 0.83, and 1.05 ng/mL after 1, 2, and 5 days after the initiation of digoxin therapy, respectively. Although the serum digoxin concentrations reached the target range, the FHR did not improve. Therefore, digoxin was discontinued, and oral flecainide therapy was started. The FHR adjusted to the normal range within 2 days from changing treatment and remained stable. TDM of digoxin along with the monitoring of clinical responses can give valuable information for decision-making during the treatment FT.

Although wearable electrocardiograms (ECGs) are being increasingly applied in clinical settings, validation methods have not been standardized. As an exploratory evaluation, we performed a multicenter clinical trial implementing an approved wearable patch ECG. Healthy male adults were enrolled in 2 study centers. The approved ECGs were deployed for 6 hours, and pulse rates were measured independently with conventional pulse oximetry at selected time points for correlation analyses. The transmission status of the data was evaluated by heart rates and classified into valid, invalid, and missing. A total of 55 subjects (40 in center 1 and 15 in center 2) completed the study. Overall, 77.40% of heart rates were within the valid range. Invalid and missing data accounted for 1.42% and 21.23%, respectively. There were significant differences in valid and missing data between centers. The proportion of missing data in center 1 (24.77%) was more than twice center 2 (11.77%). Heart rates measured by the wearable ECG and conventional pulse oximetry showed a poor correlation (intraclass correlation coefficient = 0.0454). In conclusion, we evaluated the multicenter feasibility of implementing wearable ECGs. The results suggest that systems to mitigate multicenter discrepancies and remove artifacts should be implemented prior to performing a clinical trial.

Trial registration: ClinicalTrials.gov Identifier: NCT05182684.

Duloxetine and thioctic acid (TA) are standard drugs for treating diabetic neuropathy, a primary complication associated with diabetes. In this study, ultra performance liquid chromatography coupled with tandem mass spectrometry methods was successfully developed and validated for quantifying duloxetine and TA in biological samples. The protein precipitation method was used to extract duloxetine, TA and their internal standards from beagle dog plasma. A Hypersil Gold C18 column (150 × 2.1 mm, 1.9 μm) was used for the experiment. Isocratic elution with 0.1% formic acid in acetonitrile (A) and 0.1% formic acid (B) was used for duloxetine, whereas a gradient elution with 0.03% acetic acid (A) and acetonitrile (B) was used for TA. The validated parameters included linearity, sensitivity, accuracy, precision, selectivity, matrix effect, stability, and recovery under different conditions. The linear ranges of the calibration curves for duloxetine and TA were 5-800 ng/mL and 5-1,000 ng/mL, respectively. An intra- and inter-run precision of ± 15% can be observed in all quality control samples. These methods were successfully used for pharmacokinetics (PKs) studies in beagle dogs to compare PK differences in a fixed-dose combination including duloxetine and TA and co-administration of the 2 drugs.

An extended-release (ER) fixed-dose combination (FDC) of tramadol 37.5 mg/acetaminophen 325 mg was developed due to the demand for varying dosages. This study aimed to evaluate the pharmacokinetics (PKs) for two tablets of the new developed tramadol 37.5 mg/acetaminophen 325 mg ER FDC (DW-0920, Wontran Semi ER^®) as test formulation compared to one tablet of the tramadol 75 mg/acetaminophen 650 mg ER FDC (DW-0919, Wontran ER^®) as reference formulation. A randomized, open-label, 2-way crossover study was conducted in 30 healthy subjects. Subjects were orally administered one of 2 formulations followed by an alternate formulation with a 7-day washout period. Blood samples were collected up to 36 hours post-dose. Plasma concentrations of tramadol and acetaminophen were determined using a validated high-performance liquid chromatography with tandem mass spectrometric method. The geometric mean ratios (GMRs) and their 90% confidence intervals (90% CIs) of test formulation to reference formulation were calculated for the maximum plasma concentration (C_max) and the area under the plasma concentration-time curve from zero to the last measurable time point (AUC_last). The PK profiles of 2 formulations were comparable. The GMRs (90% CI) of C_max and AUC_last for tramadol were 1.086 (1.047-1.127) and 1.008 (0.975-1.042), respectively. The corresponding values for acetaminophen were 0.956 (0.897-1.019) and 0.986 (0.961-1.011), respectively. All the values were within the bioequivalence range of 0.80-1.25. Two tablets of DW-0920 were comparable to one tablet of DW-0919. The DW-0920 may be used for optimal pharmacotherapy for pain control with a lower dose.

Trial registration: ClinicalTrials.gov Identifier: NCT01606059.