Infusion-Related Reactions Subsequent to Avelumab, Durvalumab, and Atezolizumab Administration: A Retrospective Observational Study.

BACKGROUND: Avelumab, durvalumab, and atezolizumab are anti-programmed death-ligand 1 (PD-L1) antibodies approved for clinical application in Japan. Despite targeting the same molecule, avelumab elicits a different frequency of infusion-related reactions (IRRs) compared with durvalumab and atezolizumab, leading to differences in premedication recommendations. This study aimed to collect information to verify the relationship during IRRs and the characteristics of antibody molecules, by investigating the frequency of IRRs caused by three types of antibodies and the actual status of prophylactic measures. METHODS: This single-center, retrospective observational study collected the medical records of 73 patients who received avelumab, durvalumab, or atezolizumab at Osaka University Hospital. RESULTS: The frequency of IRRs was 50.0% (12/24) for avelumab, 31.0% (8/27) for durvalumab, and 18.2% (4/22) for atezolizumab. The IRRs were grade 2 in seven patients and grade 1 in five patients treated with avelumab, grade 2 in six patients and grade 1 in two patients treated with durvalumab, and grade 1 in all patients treated with atezolizumab. Among patients in whom symptoms were observed during the first administration, measures were taken to prevent IRRs for the second administration, but cases were confirmed in which symptoms reappeared, especially in patients who received durvalumab. CONCLUSION: Our findings indicate that the frequency of IRRs due to anti-PD-L1 antibodies is higher than that previously reported in clinical trials and different modifications in antibody molecules may affect the difference in IRR frequency.

Model-Informed Vancomycin Dosing Optimization to Address Delayed Renal Maturation in Infants and Young Children with Critical Congenital Heart Disease.

Ensuring safe and effective drug therapy in infants and young children often requires accounting for growth and organ development; however, data on organ function maturation are scarce for special populations, such as infants with congenital diseases. Children with critical congenital heart disease (CCHD) often require multiple staged surgeries depending on their age and disease severity. Vancomycin (VCM) is used to treat postoperative infections; however, the standard pediatric dose (60-80 mg/kg/day) frequently results in overexposure in children with CCHD. In this study, we characterized the maturation of VCM clearance in pediatric patients with CCHD and determined the appropriate dosing regimen using population pharmacokinetic (PK) modeling and simulations. We analyzed 1,254 VCM serum concentrations from 152 postoperative patients (3 days-13 years old) for population PK analysis. The PK model was developed using a two-compartment model with allometrically scaled body weight, estimated glomerular filtration rate (eGFR), and postmenstrual age as covariates. The observed clearance in patients aged ≤ 1 year and 1-2 years was 33% and 40% lower compared with that of non-CCHD patients, respectively, indicating delayed renal maturation in patients with CCHD. Simulation analyses suggested VCM doses of 25 mg/kg/day (age ≤ 3 months, eGFR 40 mL/min/1.73 m2 ) and 35 mg/kg/day (3 months < age ≤ 3 years, eGFR 60 mL/min/1.73 m2 ). In conclusion, this study revealed delayed renal maturation in children with CCHD, could be due to cyanosis and low cardiac output. Model-informed simulations identified the lower VCM doses for children with CCHD compared with standard pediatric guidelines.

A doxycycline-inducible CYP3A4-Caco-2 cell line as a model for evaluating safety of aflatoxin B1 in the human intestine.

Exposure of humans to aflatoxin B1 (AFB1) via ingestion of contaminated agricultural products is a major concern for human health throughout the world because epoxidized AFB1, biotransformed from AFB1 by hepatic CYP3A4, is strongly hepatotoxic and hepatocarcinogenic. Intestinal epithelial cells serve as a physical and physiological barrier against xenobiotics via their intercellular tight junction (TJ) seals and the metabolizing enzyme CYP3A4. However, the effect of AFB1 on the intestinal barrier remains unclear. Here, we investigated the influence of AFB1 on these physical and physiological intestinal barriers by means of an in vitro human intestinal model utilizing doxycycline-inducible CYP3A4-expressing Caco-2 cells, in which CYP3A4 activity is comparable to that in the adult human intestine. Cellular toxicity of AFB1 in induced Caco-2 cells (i.e., cells in which expression of CYP3A4 is induced by doxycycline) was approximately 5 times that of uninduced Caco-2 cells. Exposure to 16 µM AFB1 did not decrease the transepithelial electric resistance (TEER; a measure of TJ barrier integrity) in monolayers of uninduced Caco-2 cells to 95.8 % of that in vehicle-treated cells; in contrast, in induced Caco-2 cells, TEER was reduced to 28.8 %. Exposure to 16 µM AFB1 increased paracellular permeation of 4- and 20-kDa dextrans (paracellular permeation markers) through monolayers of induced Caco-2 cells to 5.4 and 5.2 times that through uninduced Caco-2 cells. These results together show that ingested AFB1 can modulate the intestinal barrier, and that inducible CYP3A4-expressing Caco-2 cells are a promising tool for evaluating the safety of food contaminants in the human intestine.

Genome editing with removable TALEN vectors harboring a yeast centromere and autonomous replication sequence in oleaginous microalga.

Algal lipids are expected to become a basis for sustainable fuels because of the highly efficient lipid production by photosynthesis accompanied by carbon dioxide assimilation. Molecular breeding of microalgae has been studied to improve algal lipid production, but the resultant gene-modified algae containing transgenes are rarely used for outdoor culture because the use of genetically modified organisms (GMOs) is strictly restricted under biocontainment regulations. Recently, it was reported that plasmids containing yeast centromere and autonomous replication sequence (CEN/ARS) behaved as episomes in Nannochloropsis species. We previously reported that the Platinum TALEN (PtTALEN) system exhibited high activity in Nannochloropsis oceanica. Therefore, we attempted to develop a genome editing system in which the expression vectors for PtTALEN can be removed from host cells after introduction of mutations. Using all-in-one PtTALEN plasmids containing CEN/ARS, targeted mutations and removal of all-in-one vectors were observed in N. oceanica, suggesting that our all-in-one PtTALEN vectors enable the construction of mutated N. oceanica without any transgenes. This system will be a feasible method for constructing non-GMO high-performance algae.

Vascular Endothelial Growth Factor Receptor Inhibitors Impair Left Ventricular Diastolic Functions.

Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) frequently induce cardiovascular adverse events, though VEGFR-TKIs contribute to the improvement of the prognosis of patients with malignancies. It is widely accepted that VEGFR-TKIs impair left ventricular systolic functions; however, their effects on diastolic functions remain to be fully elucidated. The purpose of this study was to analyze the impact of VEGFR-TKIs on left ventricular diastolic functions. This study was designed as a retrospective single-center cohort study in Japan. We assessed 24 cases who received VEGFR-TKI monotherapy (sunitinib, sorafenib, pazopanib, axitinib) with left ventricular ejection fraction (LVEF) above 50% during the therapy at the Osaka University Hospital from January 2008 to June 2019. Left ventricular diastolic functions were evaluated by the change in echocardiographic parameters before and after the VEGFR-TKI treatment. Both septal e' and lateral e's decreased after treatment (septal e': before, 6.1 ± 1.8; after, 5.0 ± 1.9; n = 21, P < 0.01; lateral e': before, 8.7 ± 2.8; after, 6.9 ± 2.3; n = 21, P < 0.01). E/A declined after VEGFR-TKIs administration, though not statistically significantly. In 20 cases with at least one risk factor for heart failure with preserved ejection fraction (HFpEF), E/A significantly decreased (0.87 ± 0.34 versus 0.68 ± 0.14; P < 0.05) as well as the septal and lateral e's. These results suggest that treatment with VEGFR-TKIs impairs left ventricular diastolic functions in patients with preserved LVEF, especially in those with risk factors for HFpEF.

Extraction of apex beat waveform from acoustic pulse wave by sound sensing system using stochastic resonance.

With a sound sensing system using stochastic resonance (4SR), it became possible to obtain an acoustic pulse wave (APW)-a waveform created via a mixture of apex beat and heart sound. We examined 50 subjects who were healthy, with no underlying cardiovascular diseases. We could determine boundary frequency (BF) using APW and phonocardiogram signals. APW data was divided into two bands, one from 0.5 Hz to BF, and a second one from BF to 50 Hz. This permitted the extraction of cardiac apex beat (CAB) and cardiac acoustic sound (CAS), respectively. BF could be expressed by a quadratic function of heart rate, and made it possible to collect CAB and CAS in real time. According to heart rate variability analysis, the fluctuation was 1/f, which indicated an efficient cardiac movement when heart rate was 70 to 80/min. In the frequency band between 0.5 Hz and BF, CAB readings collected from the precordial region resembled apex cardiogram data. The waveforms were classified into five types. Therefore, the new 4SR sensing system can be used as a physical diagnostic tool to obtain biological pulse wave data non-invasively and repeatedly over a long period, and it shows promise for broader applications, including AI analysis.

Efficient and multiplexable genome editing using Platinum TALENs in oleaginous microalga, Nannochloropsis oceanica NIES-2145.

Algae accumulate large amounts of lipids produced by photosynthesis, and these lipids are expected to be utilized as feedstocks for sustainable new energies, known as biodiesels. Nannochloropsis species are eukaryotic microalgae that produce high levels of lipids. However, since the production costs of algal biodiesels are higher than those of fossil fuels, the improved productivity of algal lipids by molecular breeding of algae is required for practical use. In the present study, we developed a highly efficient genome-editing system involving Platinum transcription activator-like effector nucleases (TALENs) in Nannochloropsis oceanica. Platinum TALENs codon-optimized for N. oceanica were synthesized, and their DNA-binding activity was confirmed by single-strand annealing assays in human HEK293T cells. All-in-one expression vectors for Platinum TALEN targeting the nitrate reductase gene, NoNR, and acyltransferase gene, LPAT1, were transfected into Nannochloropsis species. The introduction of each Platinum TALEN revealed high genome-editing efficiency with no detectable off-target mutations at the candidate sites in N. oceanica. By simultaneously introducing TALENs targeting two genes, we obtained double mutant strains. The loss-of-function phenotype of NoNR was also confirmed. These findings will provide an essential technology for molecular breeding in Nannochloropsis species.

Progesterone receptor membrane component 1 leads to erlotinib resistance, initiating crosstalk of Wnt/ß-catenin and NF-κB pathways, in lung adenocarcinoma cells.

In non-small-cell lung cancer, mutation of epidermal growth factor receptor (EGFR) stimulates cell proliferation and survival. EGFR tyrosine kinase inhibitors (EGFR-TKIs) such as erlotinib are used as first-line therapy with drastic and immediate effectiveness. However, the disease eventually progresses in most cases within a few years due to the development of drug resistance. Here, we explored the role of progesterone membrane component 1 (PGRMC1) in acquired resistance to erlotinib and addressed the molecular mechanism of EGFR-TKI resistance induced by PGRMC1. The erlotinib-sensitive cell line PC9 (derived from non-small-cell lung cancer) and the erlotinib-resistant cell line PC9/ER were used. In proteomic and immunoblotting analyses, the PGRMC1 level was higher in PC9/ER cells than in PC9 cells. WST-8 assay revealed that inhibition of PGRMC1 by siRNA or AG-205, which alters the spectroscopic properties of the PGRMC1-heme complex, in PC9/ER cells increased the sensitivity to erlotinib, and overexpression of PGRMC1 in PC9 cells reduced their susceptibility to erlotinib. In the presence of erlotinib, immunoprecipitation assay showed that AG-205 suppressed the interaction between EGFR and PGRMC1 in PC9/ER cells. AG-205 decreased the expression of ß-catenin, accompanied by up-regulation of IκBα (also known as NFKBIA). Furthermore, AG-205 reduced the expression of ß-TrCP (also known as BTRC), suggesting that PGRMC1 enhanced the crosstalk between NF-κB (also known as NFKB) signaling and Wnt/ß-catenin signaling in an erlotinib-dependent manner. Finally, treatment with the Wnt/ß-catenin inhibitor XAV939 enhanced the sensitivity of PC9/ER cells to erlotinib. These results suggest that PGRMC1 conferred resistance to erlotinib through binding with EGFR in PC9/ER cells, initiating crosstalk between the Wnt/ß-catenin and NF-κB pathways.

Development of a Paper-Based Luminescence Bioassay for Therapeutic Monitoring of Aminoglycosides: a Proof-of-Concept Study.

Aminoglycosides are widely used antibiotics that bind to the bacterial 30S ribosomal subunit to inhibit translation. Owing to their adverse side effects and narrow therapeutic index, monitoring blood levels of aminoglycosides is important to maximize their effectiveness and minimize their toxicity. Current monitoring techniques require a well-equipped diagnostic laboratory. The present study aimed to present a proof-of-concept for a simple, low-cost biochemical assay utilizing a paper platform for the detection of serum/whole blood aminoglycosides. A paper-based bioassay chip for the assay was developed by spotting and freeze-drying cell-free transcription/translation reaction machinery for a luminescent reporter protein (NanoLuc) within an array of wax circles printed on filter paper. The paper-based chip could be used to quantify serum/whole blood aminoglycosides within clinically relevant concentrations in 30-60 min by spotting minimal volumes of samples, followed by the NanoLuc substrate, in the wax circles and detecting the associated changes in luminescence signals, using a simple digital camera. Furthermore, a one-pot assay in which cell-free transcription/translation reaction machinery and NanoLuc substrate are mixed in advance and embedded in paper could be used to detect an aminoglycoside in serum. Overall, our paper-based bioassay can potentially provide a basic platform for the simple and low-cost therapeutic monitoring of aminoglycosides, especially in resource-limited regions.

Verification of pharmacogenomics-based algorithms to predict warfarin maintenance dose using registered data of Japanese patients.

PURPOSE: Large inter-individual differences in warfarin maintenance dose are mostly due to the effect of genetic polymorphisms in multiple genes, including vitamin K epoxide reductase complex 1 (VKORC1), cytochromes P450 2C9 (CYP2C9), and cytochrome P450 4F2 (CYP4F2). Thus, several algorithms for predicting the warfarin dose based on pharmacogenomics data with clinical characteristics have been proposed. Although these algorithms consider these genetic polymorphisms, the formulas have different coefficient values that are critical in this context. In this study, we assessed the mutual validity among these algorithms by specifically considering racial differences. METHODS: Clinical data including actual warfarin dose (AWD) of 125 Japanese patients from our previous study (Eur J Clin Pharmacol 65(11):1097-1103, 2009) were used as registered data that provided patient characteristics, including age, sex, height, weight, and concomitant medications, as well as the genotypes of CYP2C9 and VKORC1. Genotyping for CYP4F2*3 was performed by the PCR method. Five algorithms that included these factors were selected from peer-reviewed articles. The selection covered four populations, Japanese, Chinese, Caucasian, and African-American, and the International Warfarin Pharmacogenetics Consortium (IWPC). RESULTS: For each algorithm, we calculated individual warfarin doses for 125 subjects and statistically evaluated its performance. The algorithm from the IWPC had the statistically highest correlation with the AWD. Importantly, the calculated warfarin dose (CWD) using the algorithm from African-Americans was less correlated with the AWD as compared to those using the other algorithms. The integration of CYP4F2 data into the algorithm did not improve the prediction accuracy. CONCLUSION: The racial difference is a critical factor for warfarin dose predictions based on pharmacogenomics.

Eukaryotic translation initiation factor 3 subunit C is associated with acquired resistance to erlotinib in non-small cell lung cancer.

The acquisition of resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs) is one of the major problems in the pharmacotherapy against non-small cell lung cancers; however, molecular mechanisms remain to be fully elucidated. Here, using a newly-established erlotinib-resistant cell line, PC9/ER, from PC9 lung cancer cells, we demonstrated that the expression of translation-related molecules, including eukaryotic translation initiation factor 3 subunit C (eIF3c), was upregulated in PC9/ER cells by proteome analyses. Immunoblot analyses confirmed that eIF3c protein increased in PC9/ER cells, compared with PC9 cells. Importantly, the knockdown of eIF3c with its siRNAs enhanced the drug sensitivity in PC9/ER cells. Mechanistically, we found that LC3B-II was upregulated in PC9/ER cells, while downregulated by the knockdown of eIF3c. Consistently, the overexpression of eIF3c increased the number of autophagosomes, proposing the causality between eIF3c expression and autophagy. Moreover, chloroquine, an autophagy inhibitor, restored the sensitivity to erlotinib. Finally, immunohistochemical analyses of biopsy samples showed that the frequency of eIF3c-positive cases was higher in the patients with EGFR-TKI resistance than those prior to EGFR-TKI treatment. Moreover, the eIF3c-positive cases exhibited poor prognosis in EGFR-TKI treatment. Collectively, the upregulation of eIF3c could impair the sensitivity to EGFR-TKI as a novel mechanism of the drug resistance.

The Metabolism of Methazolamide in Immortalized Human Keratinocytes, HaCaT Cells.

OBJECTIVE: Drug therapy is occasionally accompanied by an idiosyncratic severe toxicity, which occurs very rarely, but can lead to patient mortality. Methazolamide, an anti-glaucomatous agent, could cause severe skin eruptions called Stevens-Johnson syndrome/toxic epidermal necrolyis (SJS/TEN). Its precise etiology is still uncertain. In this study, the metabolism of methazolamide was investigated in immortalized human keratinocytes to reveal the possible mechanism which causes SJS/TEN. METHODS: The metabolism of methazolamide was studied using immortalized human keratinocytes, HaCaT cells. HPLC was used to isolate a metabolite from the culture medium. Mass spectrometry (LCMS/ MS) was employed for its characterization. Three typical chemical inducers were assessed for the inducibility of cytochrome P450, and methimazole was used as the inhibitor of flavin-containing monooxygenase (FMO). RESULTS: A sulfonic acid, N-[3-methyl-5-sulfo-1,3,4-thiadiazol-2(3H)-ylidene]acetamide (MSO) was identified as the final metabolite. Dexamethasone and ß-naphthoflavone behaved as an inducer of cytochrome P450 in the metabolism, but isoniazid did not. The effect of methimazole was not consistent. We did not detect any glucuronide nor any mercapturic acid (N-acetylcysteine conjugate). CONCLUSION: N-[3-methyl-5-sulfo-1,3,4-thiadiazol-2(3H)-ylidene]acetamide (MSO) is not considered to be a direct product of an enzymatic reaction, but rather an auto-oxidation product of N-[3-methyl-5- sulfe-1,3,4-thiadiazol-2(3H)-ylidene]acetamide, a chemically unstable sulfenic acid, which is produced by cytochrome P450 from the ß-lyase product of cysteine conjugate of methazolamide. MSO is considered to be susceptible to glutathione and to return to glutathione conjugate of methazolamide, forming a futile cycle. A hypothetical scenario is presented as to the onset of the disease.

Gab1 adaptor protein acts as a gatekeeper to balance hepatocyte death and proliferation during acetaminophen-induced liver injury in mice.

UNLABELLED: Acetaminophen (APAP) overdose is the leading cause of drug-induced acute liver failure. In APAP-induced acute liver failure, hepatocyte death and subsequent liver regeneration determines the prognosis of patients, making it necessary to identify suitable therapeutic targets based on detailed molecular mechanisms. Grb2-associated binder 1 (Gab1) adaptor protein plays a crucial role in transmitting signals from growth factor and cytokine receptors to downstream effectors. In this study, we hypothesized that Gab1 is involved in APAP-induced acute liver failure. Hepatocyte-specific Gab1 conditional knockout (Gab1CKO) and control mice were treated with 250 mg/kg of APAP. After APAP treatment, Gab1CKO mice had significantly higher mortality and elevated serum alanine aminotransferase levels compared to control mice. Gab1CKO mice had increased hepatocyte death and increased serum levels of high mobility group box 1, a marker of hepatocyte necrosis. In addition, Gab1CKO mice had reduced hepatocyte proliferation. The enhanced hepatotoxicity in Gab1CKO mice was associated with increased activation of stress-related c-Jun N-terminal kinase (JNK) and reduced activation of extracellular signal-regulated kinase and AKT. Furthermore, Gab1CKO mice showed enhanced mitochondrial translocation of JNK accompanied by an increase in the release of mitochondrial enzymes into the cytosol, which is indicative of increased mitochondrial dysfunction and subsequent nuclear DNA fragmentation. Finally, in vitro experiments showed that Gab1-deficient hepatocytes were more susceptible to APAP-induced mitochondrial dysfunction and cell death, suggesting that hepatocyte Gab1 is a direct target of APAP-induced hepatotoxicity. CONCLUSION: Our current data demonstrate that hepatocyte Gab1 plays a critical role in controlling the balance between hepatocyte death and compensatory hepatocyte proliferation during APAP-induced liver injury.

Multicomponent high-performance liquid chromatography/tandem mass spectrometry analysis of ten chemotherapeutic drugs in wipe samples.

Progress in chemotherapy leads to increased numbers and variety of chemotherapeutic drugs, and multicomponent analysis of these drugs is a necessary step. We used liquid chromatography-tandem mass spectrometry and developed a multicomponent analysis of ten drugs used in chemotherapy: vindesine, vincristine, vinblastine, doxorubicin, epirubicin, ifosfamide, cyclophosphamide, irinotecan, docetaxel, and paclitaxel. We selected five internal standards for each category of drug, because the ionization efficiencies of product ions varied widely. The total run time was 22min, applying a gradient elution of water and acetonitrile in the presence of 0.1% formic acid. The lower limit of quantification was 50ng/wipe samples for vindesine, vincristine, and vinblastine, and 5ng/wipe samples for the remaining seven drugs. Accuracy (88.6-112.9%, 85.2-111.7%) and precision (1.0-11.5%CV, 3.6-14.4%CV) in within-run and between-run assays of QC solutions were acceptable. Without outliers, in within-run and between-run assays of QC samples, accuracy was 90.6-113.9% and 91.1-130.4%, respectively, and precision was 2.2-19.0%CV and 4.8-14.9%CV, respectively. Accuracy and precision of High QC samples of irinotecan were deviated. Our analysis procedure has sufficient sensitivity and is convenient enough for regular monitoring.

ATF6alpha promotes astroglial activation and neuronal survival in a chronic mouse model of Parkinson's disease.

Accumulating evidence suggests a crucial role for the unfolded protein response (UPR) in Parkinson's disease (PD). In this study, we investigated the relevance of the UPR in a mouse model of chronic MPTP/probenecid (MPTP/P) injection, which causes severe and persistent degeneration of dopaminergic neurons. Enhanced activation of the UPR branches, including ATF6α and PERK/eIF2α/ATF4, was observed after MPTP/P injections into mice. Deletion of the ATF6α gene accelerated neuronal degeneration and ubiquitin accumulation relatively early in the MPTP/P injection course. Surprisingly, astroglial activation was strongly suppressed, and production of the brain-derived neurotrophic factor (BDNF) and anti-oxidative genes, such as heme oxygenase-1 (HO-1) and xCT, in astrocytes were reduced in ATF6α -/- mice after MPTP/P injections. Decreased BDNF expression in ATF6α -/- mice was associated with decreased expression of GRP78, an ATF6α-dependent molecular chaperone in the ER. Decreased HO-1 and xCT levels were associated with decreased expression of the ATF4-dependent pro-apoptotic gene CHOP. Consistent with these results, administration of the UPR-activating reagent tangeretin (5,6,7,8,4'-pentamethoxyflavone; IN19) into mice enhanced the expression of UPR-target genes in both dopaminergic neurons and astrocytes, and promoted neuronal survival after MPTP/P injections. These results suggest that the UPR is activated in a mouse model of chronic MPTP/P injection, and contributes to the survival of nigrostriatal dopaminergic neurons, in part, through activated astrocytes.

Evaluation of environmental contaminations and occupational exposures involved in preparation of chemotherapeutic drugs.

Many healthcare workers are concerned about the risk of occupational exposures to hazardous drugs. The Japanese Society of Hospital Pharmacists (JSHP) revised the "Guidelines for the Handling of Antineoplastic Drugs in Hospitals", however, the precautions and awareness of handling drugs varied in institutions. We assessed the levels of environmental contaminations in our hospital and urinary excretion of cyclophosphamide (CP) and ifosfamide (IF) in pharmacists and nurses. In environmental studies, we obtained samples by wiping the surfaces around two biological safety cabinets (BSCs) on eight days for four months. One BSC was equipped in hospital pharmacy and the other was equipped in an oncology ward, and used for preparing chemotherapeutic drugs for outpatients and for inpatients, respectively. We obtained the urine samples from 6 pharmacists and 2 nurses. We used solid phase extraction (SPE) as a convenient extraction procedure and liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) for the analysis of the samples. CP was detected on the working surfaces inside both BSCs, and detected at low levels on the back surfaces of the BSCs and at the working tables around the BSCs. IF over the LLOQ was not detected in both BSCs. CP and IF were not detected in all urine samples of pharmacists and nurses. Detection frequencies and amounts of these drugs were low levels, compared with previous reports in Japan, and our results showed that improving awareness about handling hazardous drugs could reduce the risk of the occupational exposures.

Pharmacokinetic behavior of intravitreal triamcinolone acetonide prepared by a hospital pharmacy.

PURPOSE: We developed a new hospital pharmaceutical preparation of triamcinolone acetonide (TA) for intravitreal injections using sodium hyaluronate as the vehicle. The purpose of this study was to compare the pharmacokinetic behavior of this hospital pharmacy preparation of TA (HPP-TA) to that of a commercial preparation of TA (CP-TA) in rats. METHODS: We injected the two preparations of TA into the vitreous humor of male Wistar rats. The rats were killed between days 1 and 21, and the concentration of TA in the vitreous was measured by high-performance liquid chromatography to determine the pharmacokinetic parameters. We also examined the microscopic appearance of the TA particles in these preparations. RESULTS: The elimination half-life was 6.08 days for the CP-TA and 5.78 days for the HPP-TA. A two-compartment model was suitable to approximate the pharmacokinetic behavior of HPP-TA in the vitreous body, but this model was not suitable for CP-TA, because its pharmacokinetic behavior was not sufficiently stable. The particle size of CP-TA was largest, followed by TA powder and HPP-TA. Many particles were agglutinated in the CP-TA preparation, whereas the TA particles were fine and dispersed in the HPP-TA medium. CONCLUSIONS: The TA particle size and the suspension medium are likely important factors in the preparation of a safe and stable suspension of TA. HPP-TA satisfied these requirements and should be suitable for clinical use.

Examination of purification methods and development of intravitreal injection of triamcinolone acetonide.

PURPOSE: Intravitreal injection of triamcinolone acetonide (TA) is used in ophthalmic treatment, but the reliability of commercially available TA preparations has still not been established. We evaluated two previously reported purification methods, and developed a more reliable TA injection which can be prepared in a hospital pharmacy. METHODS: We tested the two methods previously reported for purifying commercial TA preparations, the sedimentation and the filtration and backflushing methods. We developed a new TA injection made of pure TA suspended in 0.5% sodium hyaluronate. We measured the TA content in each preparation by high-performance liquid chromatography to evaluate the three methods. RESULTS: In the sedimentation purification method, the TA content of a nominal 4-mg preparation varied from 1.43 to 7.37 mg, and the average recovery rate was 91.6%. In the filtration and backflushing method, TA content was 0.10-10.33 mg and recovery was 59.5%. In the TA injection we developed, the mean TA content was 102.5% (SD, 0.24; CV, 2.9%). The stability of this preparation was 99% after sterilization, and 97% after 3 months of storage. CONCLUSIONS: The results of our investigation showed that the purification methods used for commercial preparations are simple and easy but not precise enough for an intravitreal injection. In contrast, the TA injection prepared by our method is reliable, stable, and safe enough for clinical use.