Factors Influencing Serum Posaconazole Concentrations in Patients with Hematologic Malignancies Receiving Delayed-Release Tablets.

BACKGROUND: Posaconazole (PCZ) plays a crucial role in the prophylaxis and treatment of invasive fungal infections in hematologic malignancies. PCZ concentrations reportedly vary among patients receiving delayed-release tablets (DRT). However, the factors influencing these concentrations remain insufficiently elucidated. Therefore, this study aimed to evaluate the factors influencing PCZ concentrations and their effect on the probability of target attainment (PTA) using a population pharmacokinetic (PPK) approach. We also explored the relationship between PCZ exposure and hepatotoxicity. METHODS: This retrospective study included adult patients with hematologic malignancies who received PCZ DRT. A PPK model was developed based on observational data for 130 concentrations in 28 patients. Simulation analyses were performed to assess the PTA at standard doses of 0.7 and 1.0 mg/L for prophylaxis and treatment, respectively. Estimated concentrations were used to evaluate the correlation between PCZ exposure and hepatotoxicity. RESULTS: Significant factors influencing PCZ concentrations included body weight, serum total protein levels, and diarrhea. Diarrhea correlated with decreased PCZ concentrations resulting in up to 26% lower PTA compared with that without diarrhea. Moreover, PTA declined markedly as the total protein levels decreased from 6.6 g/dL to 4.4 g/dL. The incidence of hepatotoxicity was 17.4% (4/23); no significant relationship could be established between the PCZ concentrations and hepatotoxicity (P = 0.188). CONCLUSIONS: We identified the factors affecting PCZ exposure, which could not be detected by PPK analysis using data from clinical trials. Our results suggest that the generally recommended dose of PCZ causes underexposure in patients with hematologic malignancies characterized by high body weight, hypoproteinemia, or concurrent diarrhea. Therapeutic drug monitoring for DRT may be recommended, especially in patients with these risk factors.

Risk Factors of Cetuximab-Induced Hypomagnesemia and the Effect of Magnesium Prophylaxis in Patients with Head and Neck Cancer: A Retrospective Study.

Hypomagnesemia is a characteristic adverse event of cetuximab in patients with head and neck cancer (HNC). However, there is limited information about its prevalence, risk factors, and preventive strategies. This study aimed to investigate the risk factors of hypomagnesemia and examine the preventive effects of prophylactic magnesium (Mg) administration. We initially investigated HNC patients treated with cetuximab between 2013 and 2019. Our institute started prophylactic Mg treatment (20-mEq Mg sulfate administration before cetuximab) in practice during this period. We retrospectively assess the preventive efficacy by comparing patients before and after its implementation. In total, 109 patients were included. In 60 patients without prophylaxis, all-grade and grade ≥2 hypomagnesemia at 3 months occurred in 61.7 and 15.0% of patients. The incidence of hypomagnesemia was not affected by regimens and concomitant medications. In 49 patients treated with prophylactic Mg treatment, there was no significant decrease in the cumulative incidence of hypomagnesemia. However, the preventive Mg treatment eliminated the need for additional Mg repletion to maintain Mg levels in patients treated with paclitaxel + cetuximab. A risk factor in patients without prophylaxis was a low Mg level at pre-treatment (≤2.0 mg/dL) (odds ratio: 6.03, 95% confidence interval: 1.78-20.4, p = 0.004), whereas that in patients with prophylaxis was the number of cetuximab doses (≥10) (odds ratio: 5.50, 95% confidence interval: 1.52-19.87, p = 0.009). In conclusion, a low pre-treatment Mg level was the only risk factor that could be avoided by prophylactic Mg administration. This preventive intervention is recommended for managing cetuximab-induced hypomagnesemia.

Interindividual variability in statin pharmacokinetics and effects of drug transporters.

INTRODUCTION: Statins are HMG-CoA reductase inhibitors that primarily lower plasma cholesterol levels. It has been suggested that the myotoxic response is a direct result of hydroxymethylglutaryl-CoA reductase inhibition and dose-dependent. Therefore, an accurate understanding of the combination of drugs that inhibit statin metabolism and factors that cause interindividual variability in the pharmacokinetics of statin is important to avoid serious side effects of statins. Relevant articles included in this review were identified through a PubMed search (through May 2023). AREAS COVERED: This review provides an overview of hepatic and intestinal metabolism of statins, followed by a discussion of drug-drug interactions and interindividual variables that influence statin pharmacokinetics: gut bacteria, disease, and pharmacokinetics-related genetic polymorphisms. EXPERT OPINION: Drug-drug interactions have a strong influence on statin pharmacokinetics, and gut microbiota, disease, and genetic polymorphisms all contribute significantly to interindividual variation in statin pharmacokinetics. Individual optimization of statin treatment requires studies that consider the progression of the disease and associated changes in concomitant medications.

Clinical Pharmacokinetics and Pharmacodynamics of Letermovir in Allogenic Hematopoietic Cell Transplantation.

Letermovir is a newly developed antiviral agent used for the prophylaxis of human cytomegalovirus infections in patients undergoing allogeneic hematopoietic cell transplantation. This novel anti-cytomegalovirus drug, used for the prophylaxis of cytomegalovirus reactivation until approximately 200 days after transplantation, effectively reduces the risk of clinically significant cytomegalovirus infection. No human counterpart exists for the terminase complex; letermovir is virus specific and lacks some toxicities previously observed with other anti-cytomegalovirus drugs, such as cytopenia and nephrotoxicity. The absolute bioavailability of letermovir in healthy individuals is estimated to be 94% based on a population-pharmacokinetic analysis. In contrast, oral administration of letermovir to patients undergoing hematopoietic cell transplantation results in lower exposure than that in healthy individuals. Renal or hepatic impairment does not influence the intrinsic clearance of letermovir. Co-administration of letermovir may alter the plasma concentrations of other drugs, including itself, as it acts as a substrate and inhibitor/inducer of several drug-metabolizing enzymes and transporters. In particular, attention should be paid to the drug-drug interactions between letermovir and calcineurin inhibitors or azole antifungal agents, which are commonly used in patients undergoing hematopoietic cell transplantation. This article reviews and summarizes the clinical pharmacokinetics and pharmacodynamics of letermovir, focusing on patients undergoing hematopoietic cell transplantation, healthy individuals, and specific patient subsets.

Eye-tracking-based analysis of pharmacists' thought processes in the dispensing work: research related to the efficiency in dispensing based on right-brain thinking.

BACKGROUND: Pharmacists should be aware of their thought processes in dispensing work, including differences in the dispensing complexities owing to different drug positions in the left, center, and right areas. Dispensing errors associated with "same-name drugs (a pair of drugs with the same name but a different ingredient quantity)" are prevalent and often negatively affect patients. In this study, using five pairs of comparative models, the gaze movements of pharmacists in dispensing work were analyzed using an eye-tracking method to elucidate their thought processes. METHODS: We prepared verification slides and displayed them on a prescription monitor and three drug rack monitors. The dispensing information (drug name, drug usage, location display, and total amount) was displayed on a prescription monitor. A total of 180 drugs including five target drugs were displayed on the three drug rack monitors. Total gaze points in the prescription area, those in the drug rack area, total vertical movements between the two areas, and time required to dispense drugs were measured as the four classifications Gaze 1, Gaze 2, Passage, and Time, respectively. First, we defined the two types of location displays as "numeral combination" and "color/symbol combination." Next, we defined two pairs of models A1-A2 (numerals) and B1-B2 (color/symbol) to compare differences between the left and right areas. Moreover, three pairs of models C1-C2 (left), D1-D2 (center), and E1-E2 (right) were established to compare differences between "numeral combination" and "color/symbol combination." RESULTS: Significant differences in the complexities of dispensing work were observed in Gaze 2, Passage, and Time between the models A1-A2 (A1B2), and in Gaze 2 and Time between the models C1-C2, D1-D2, and E1-E2 (C1>C2, D1>D2, and E1>E2, respectively). CONCLUSIONS: Using the current dispensing rules, pharmacists are not good at dispensing drugs located in the right area. An effective measure for reducing the dispensing complexity is to introduce visual information in the prescription content; the utilization of the right brain facilitates reducing the complexity in the right dispensing area.

Safety and tolerability of OP-724 in patients with haemophilia and liver cirrhosis due to HIV/HCV coinfection: an investigator-initiated, open-label, non-randomised, single-centre, phase I study.

OBJECTIVE: Patients with haemophilia and HIV who acquire hepatitis C virus (HCV) after receiving contaminated blood products can experience accelerated progression of liver fibrosis and a poor prognosis, making liver disease a prominent cause of mortality among these patients. In the current study, we aimed to evaluate the safety and tolerability of the potential antifibrotic agent OP-724-a CREB-binding protein/ß-catenin inhibitor-in this patient subset. DESIGN: In this single-centre, open-label, non-randomised, phase I trial, we sequentially enrolled patients with cirrhosis following HIV/HCV coinfection classified as Child-Pugh (CP) class A or B. Five patients received an intravenous infusion of OP-724 at doses of 140 or 280 mg/m2 for 4 hours two times weekly over 12 weeks. The primary endpoint was the incidence of serious adverse events (SAEs). Secondary endpoints included the incidence of AEs and improved liver stiffness measure (LSM), as determined by vibration-controlled transient elastography. This study was registered at ClinicalTrials.gov (NCT04688034). RESULTS: Between 9 February 2021 and 5 July 2022, five patients (median age: 51 years) were enrolled. All five patients completed 12 cycles of treatment. SAEs were not observed. The most common AEs were fever (60%) and gastrointestinal symptoms (diarrhoea: 20%, enterocolitis: 20%). Improvements in LSM and serum albumin levels were also observed. CONCLUSION: In this preliminary assessment, intravenous administration of 140 or 280 mg/m2/4 hours OP-724 over 12 weeks was well tolerated by patients with haemophilia combined with cirrhosis due to HIV/HCV coinfection. Hence, the antifibrotic effects of OP-724 warrant further assessment in patients with cirrhosis. TRIAL REGISTRATION NUMBER: NCT04688034.

Safety and efficacy of ripasudil eye drops in preterm infants with retinopathy of prematurity: phase 1/2, open label, single-arm trial.

PURPOSE: To assess the safety and efficacy of ripasudil for retinopathy of prematurity (ROP). STUDY DESIGN: Phase 1/2, multicenter, open-label, single-arm, 12-week clinical trial. METHODS: Infants born with gestational age (GA) of ≤ 32 weeks or weight of ≤ 1500 g with zone I or II, ≥ stage 1, ROP in both eyes were enrolled. Ripasudil eye drops were administered to patients in both eyes. Phase 1 was a dose-escalation study (once daily for 1 week, then twice daily for 2 weeks); an additional dosing up to 9 weeks was allowed if no safety issues occurred. In phase 2, ripasudil was administered twice daily for up to 12 weeks. Adverse events were assessed. The proportion of patients with type 1 ROP progression, number of days for type 1 ROP progression, and progression to the most advanced ROP stage were estimated. RESULTS: Twenty-four infants were enrolled (phase 1, n = 3; phase 2, n = 21). Nineteen and four patients experienced systemic and ocular adverse events, respectively. Efficacy endpoints were not different between the ripasudil and historical control groups. However, in the GA ≤ 27 weeks subgroup, fewer patients progressed to type 1 ROP in the ripasudil than in the historical control group (P = 0.09). In the GA ≤ 27 weeks subgroups, the 25th percentile for the number of days for type 1 ROP progression was 22 days in the historical control group and 44 days in the ripasudil group. CONCLUSION: Ripasudil was safe and inhibited/delayed type 1 ROP progression, especially in infants with short GA.