Pharmacokinetic characterization of favipiravir in patients with COVID-19.

This prospective observational study describes the pharmacokinetic characteristics of favipiravir in adult patients hospitalized for mild to moderate COVID-19 with a positive RT-PCR test. Favipiravir was administered for 5 days, with a loading dose of 3200 mg and a maintenance dose of 1200 mg/day. Serial blood samples were collected on Day 2 and Day 4 of the therapy. Laboratory findings of the patients (n = 21) and in-hospital mortality were recorded. Favipiravir concentrations exhibited substantial variability and a significant decrease during the treatment of COVID-19. The median favipiravir trough concentration (C0-trough ) on Day 2 was 21.26 (interquartile range [IQR], 8.37-30.78) µg/mL, whereas it decreased significantly to 1.61 (IQR, 0.00-6.41) µg/mL on Day 4, the area under the concentration-time curve decreased by 68.5%. Day 2 C0-trough of female patients was higher than male patients. Our findings indicate that favipiravir concentrations show significant variability during the treatment of COVID-19 and therapeutic drug monitoring may be necessary to maintain targeted concentrations.

The effectiveness of BD Vacutainer® Plus Urinalysis Preservative Tubes in preservation of urine for chemical strip analysis and particle counting.

INTRODUCTION: The aim of this study was to evaluate the stability of urine collected in preservative tubes for chemistry strip analyses and particle counting to determine whether the transport of urine samples with all of their constituents is possible. MATERIALS AND METHODS: 275 pathologic urine specimens were included. Each urine sample was evaluated after 4, 8, 12, 24, and 48 hours of storage in BD Vacutainer(®) Plus Urinalysis Preservative (BD UAP) tubes and compared with refrigeration at 4 °C. All analyses were peformed on H-800 and FUS-200 automatic modular urine analyzers (Dirui Industry, Changchun, China). The kappa coefficients (κ), false positive (FP) and false negative (FN) rates were evaluated. κ > 0.8 was accepted as good agreement. RESULTS: Haemoglobin (Hb), leucocyte esterase (LE), and protein (Pro) analyses should be performed within 4 hours, whereas glucose (Glc) was stable until the end of 48 hours in both storage conditions. Nitrite (Nit) was well preserved in BD UAP tubes for 24 hours but was stable only up to 8 hours at 4 °C. Bilirubin (Bil) had very high FN rates even at 4 hours in both conditions. The particle counting showed high FN rates for white blood cells (WBC) and red blood cells (RBC), whereas squamous epithelial cells (EC) were stable up to 8 hours in both conditions. CONCLUSIONS: Preanalytical requirements for both urine chemical strip analyses and particle counting in a unique sample were not met in either condition. Thus, the transfer of urine samples for centralization of urinalysis is not yet feasible.

Diagnostic utility of osteocalcin, undercarboxylated osteocalcin, and alkaline phosphatase for osteoporosis in premenopausal and postmenopausal women.

BACKGROUND: We aimed to investigate the diagnostic utility of osteocalcin (OC), undercarboxylated osteocalcin (ucOC), and alkaline phosphatase (ALP) in pre- and postmenopausal women for femoral neck, L1-4, and L2-4 bone mineral density (BMD) values by taking into consideration their age, body mass index (BMI), and menopausal status. METHODS: Premenopausal (N=40) and postmenopausal cases (N=42) were classified as 25-34 or 35-45 yr of age and within the first 5 yr or 5 yr or more after the onset of menopause, respectively. RESULTS: Among the groups, statistical differences were found for age, BMI, OC, ucOC, ALP, femoral neck BMD, L1-4 BMD, and L2-4 BMD. The highest serum OC, ucOC, and ALP levels were observed in cases within the first 5 yr after the onset of menopause, probably due to a more rapid bone turnover rate. The best predictors for the femoral neck osteoporosis were ALP, OC, and calcium (areas under the ROC curve [AUC]=0.882, 0.829, and 0.761, respectively), and those for L1-4 and L2-4 osteoporosis were OC, ALP, and ucOC (AUC=0.949, 0.873, and 0.845; and 0.866, 0.819, and 0.814, respectively). Multiple logistic regression analysis revealed that the most discriminative parameter for osteoporosis was OC. CONCLUSIONS: These results indicate that serum OC levels, with or without ucOC and ALP, may be useful to monitor follow-up changes that currently cannot be assessed with BMD and to diagnose femoral neck, L1-4 spine, and L2-4 spine osteoporosis.