Risk Evaluation of Proton Pump Inhibitors for Panitumumab-Related Hypomagnesemia in Patients with Metastatic Colorectal Cancer.

Hypomagnesemia commonly occurs as a side effect of panitumumab treatment. In severe cases, temporary discontinuation or dose reduction of panitumumab may be necessary. Proton pump inhibitors (PPIs) are reportedly potential risk factors for hypomagnesemia. We conducted a multicenter study to assess the impact of PPIs on the risk of grade 3-4 hypomagnesemia in patients with metastatic colorectal cancer (mCRC) receiving panitumumab. We adjusted for potential bias using a propensity score-matched analysis and retrospectively reviewed the medical records of patients. Hypomagnesemia severity was graded according to the Common Terminology Criteria for Adverse Events, version 5.0. A total of 165 patients were enrolled in this study. The incidence of grade 3-4 hypomagnesemia was significantly higher in the PPI group than in the non-PPI group, both before (20.0% [30/60] vs. 8.0% [8/105], p = 0.026) and after propensity score matching (16.2% [6/37] vs. 0% [0/37], p = 0.025). In the propensity score-matched cohort, the risk of grade 3-4 hypomagnesemia was significantly higher in the PPI group (odds ratio, 2.19; 95% confidence interval, 1.69-2.84; p = 0.025). These findings suggest that concomitant use of PPIs significantly increases the risk of grade 3-4 hypomagnesemia in patients with mCRC receiving panitumumab. Therefore, close monitoring of these patients is imperative.

Safety and blood levels of daratumumab after switching from intravenous to subcutaneous administration in patients with multiple myeloma.

The intravenous administration (IV) of daratumumab sometimes causes an infusion reaction and needs a long infusion time. Recently, a subcutaneous formulation (SC) of daratumumab, which has fewer infusion reactions and shorter administration time, was approved. However, because SC has a fixed dose, overdosing is a concern for patients with low body weights. In this study, we investigated the safety and blood levels of daratumumab after switching from IV to SC in patients with multiple myeloma (MM). Patients who switched from IV to SC of daratumumab between June 2021 and May 2022 at Kobe City Medical Center General Hospital were included in the study. Blood daratumumab levels were measured using liquid chromatography-tandem mass spectrometry. Safety after switching from IV to SC was evaluated for six months and graded according to the Common Terminology Criteria for Adverse Events, version 5.0. The median body weight of ten patients included in the analysis was 57.4 kg (range: 45.0-74.4). Blood daratumumab levels were significantly increased after switching to SC (p = 0.002); median through concentration at the last IV dose was 403.6 µg/mL (range: 96.3-776.3) and that at the third SC dose was 557.1 µg/mL (range: 288.3-997.2). Grade 1-2 injection site reactions were observed in six patients (60.0%) after switching to SC. A new grade 3 adverse event was observed in only one patient (neutropenia). The blood levels of daratumumab were significantly increased after switching from IV to SC in patients with MM; however, the dosage was tolerable.

Pharmacist-Urologist Collaborative Management for Patients with Renal Cell Carcinoma Receiving Pazopanib Monotherapy.

Pazopanib is one of recommended treatment for metastatic renal cell carcinoma (RCC). Despite its effectiveness, patients often difficult to continue pazopanib treatment due to adverse events (AEs). We established an ambulatory care pharmacy practice that enables pharmacist-urologist collaboration to manage patients with RCC. This study evaluated the usefulness of this collaborative management. We retrospectively reviewed the medical records of 51 consecutive patients with metastatic RCC receiving pazopanib at the Kobe City Medical Center General Hospital between April 2014 and December 2020. Our collaborative management was implemented in October 2016. The time to pazopanib discontinuation was compared between patients who started pazopanib before (n = 30) and after (n = 21) the implementation of the collaborative management. A multivariate Cox regression analysis was performed to analyze the factors associated with pazopanib discontinuation. In the collaborative management, the oncology pharmacists had a total of 245 face-to-face patient consultations, and provided 286 suggestions [according to supportive care in pazopanib treatment (214 suggestions) were most frequent], and 236 (82.5%) were accepted by urologists. The median time to discontinuation (6.1 months vs. 2.4 months, p = 0.024) was significantly longer in the after group. Multivariate analysis showed that collaborative management (hazard ratio (HR) 0.49, 95% confidence interval (CI) 0.26-0.88, p = 0.017), and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2 at pazopanib initiation (HR 3.87, 95% CI 1.47-9.13, p = 0.008) were significantly associated with pazopanib discontinuation. These results suggested that, compared to conventional management, collaborative management is effective at prolonging the time to pazopanib discontinuation.

Pharmacokinetics of Temozolomide in a Patient With Glioblastoma Undergoing Hemodialysis: A Short Communication.

BACKGROUND: Temozolomide (TMZ) is an alkylating agent used to treat glioblastoma. However, the pharmacokinetics of TMZ to establish a treatment strategy for patients undergoing hemodialysis (HD) remain unclear. In this case report, we evaluated the pharmacokinetics and HD removal rate of TMZ in a patient with glioblastoma undergoing HD to determine optimal dosing of TMZ. METHODS: A 78-year-old man with glioblastoma who underwent HD 3 times a week was treated with TMZ concomitant with radiotherapy. One dose of TMZ was prescribed at 75 mg/m 2 on the day before HD and another dose of 37.5 mg/m 2 on the day before non-HD. Peak and trough concentrations (1 hour and 12 hours after dosing, respectively) were evaluated before HD and on non-HD days. HD removal rate of TMZ was calculated based on the predialyzer and postdialyzer plasma concentrations. Furthermore, the TMZ plasma concentrations were measured using liquid chromatography-tandem mass spectrometry. RESULTS: The mean plasma peak and trough concentrations ± SD after 75 mg/m 2 TMZ were 2917 ± 914 and 108 ± 17.6 ng/mL, respectively. Those after 37.5 mg/m 2 TMZ dosage were 1305 ± 650 and 53.8 ± 11.8 ng/mL, respectively. The mean HD TMZ removal rate was 84.9 ± 1.9%. CONCLUSIONS: TMZ was tolerable in patients undergoing HD. Based on the data from a single individual pharmacokinetic perspective, the pharmacokinetics of TMZ in this patient undergoing HD were comparable with those observed in patients with normal renal function. In addition, it may be reasonable to administer TMZ after HD because of the high HD removal rate.

Impact of prior bevacizumab therapy on the incidence of ramucirumab-induced proteinuria in colorectal cancer: a multi-institutional cohort study.

BACKGROUND: The association between prior bevacizumab (BEV) therapy and ramucirumab (RAM)-induced proteinuria is not known. We aimed to investigate this association in patients with metastatic colorectal cancer (mCRC). METHODS: mCRC patients who received folinic acid, fluorouracil, and irinotecan (FOLFIRI) plus RAM were divided into with and without prior BEV treatment groups. The cumulative incidence of grade 2-3 proteinuria and rate of RAM discontinuation within 6 months (6M) after RAM initiation were compared between the two groups. RESULTS: We evaluated 245 patients. In the Fine-Gray subdistribution hazard model including prior BEV, age, sex, comorbidities, eGFR, proteinuria ≥ 2 + at baseline, and later line of RAM, prior BEV treatment contributed to proteinuria onset (P < 0.01). A shorter interval between final BEV and initial RAM increased the proteinuria risk; the adjusted odds ratios (95% confidence intervals) for the intervals of < 28 days, 28-55 days, and > 55 days (referring to prior BEV absence) were 2.60 (1.23-5.51), 1.51 (1.01-2.27), and 1.04 (0.76-1.44), respectively. The rate of RAM discontinuation for ≤ 6M due to anti-VEGF toxicities was significantly higher in the prior BEV treatment group compared with that in the no prior BEV treatment group (18% vs. 6%, P = 0.02). Second-line RAM discontinuation for ≤ 6M without progression resulted in shorter overall survival of 132 patients with prior BEV treatment (P < 0.01). CONCLUSION: Sequential FOLFIRI plus RAM after BEV failure, especially within 55 days, may exacerbate proteinuria. Its escalated anti-VEGF toxicity may negatively impact the overall survival.

Population pharmacokinetics and exposure-clinical outcome relationship of remdesivir major metabolite GS-441524 in patients with moderate and severe COVID-19.

Although remdesivir, a prodrug of nucleoside analog (GS-441524), has demonstrated clinical benefits in coronavirus disease 2019 (COVID-19) treatment, its pharmacokinetics (PKs) in patients with COVID-19 remain poorly understood. Therefore, in this study, the PKs of remdesivir and its major metabolite, GS-441524, were evaluated using a population PK (PopPK) approach to understand the PK aspect and exposure-clinical outcome relationship. The serum concentrations of remdesivir and GS-441524 (102 points in 39 patients) were measured using liquid chromatography-tandem mass spectrometry. All patients received 200 mg remdesivir on the first day, followed by 100 mg on 2-5 days, except for one patient who discontinued remdesivir on day 4. The median (range) age, body surface area, and estimated glomerular filtration rate (eGFR) were 70 (42-85), 1.74 m2 (1.36-2.03), and 68 mL/min/1.73 m2 (33-113), respectively. A compartment model with first-order elimination combined with remdesivir and GS-441524 was used for nonlinear mixed-effects model analysis. Remdesivir was rapidly eliminated after infusion, whereas GS-441524 was eliminated relatively slowly (half-time = 17.1 h). The estimated apparent clearance (CL) and distribution volume of GS-441524 were 11.0 L/h (intersubject variability [ISV]% = 43.0%) and 271 L (ISV% = 58.1%), respectively. The CL of GS-441524 was significantly related to the eGFR (CL × [eGFR/68]0.745 ). The post hoc area under the curve of GS-441524 was unrelated to the recovery rate or aspartate aminotransferase/alanine aminotransferase elevation. Overall, PopPK analysis showed the rapid elimination of remdesivir in the blood, and GS-441524 accumulation depended on eGFR in patients with COVID-19. However, no relevance of exposure-clinical outcome was not suggestive of the dose adjustment of remdesivir.

Population Pharmacokinetics of Nivolumab in Japanese Patients with Nonsmall Cell Lung Cancer.

BACKGROUND: Nivolumab is an antiprogrammed death-1 (PD-1) antibody used for immuno-oncological therapy of various cancers, including nonsmall cell lung cancer (NSCLC). This study aimed to characterize the real-world population pharmacokinetics (PK) of nivolumab in patients with NSCLC. METHODS: PK samples were collected by opportunistic sampling of Japanese patients with NSCLC treated with nivolumab monotherapy. Population PK analysis was performed using a two-compartment model in Nonlinear Mixed Effect Model. Patient-specific factors such as body weight, age, sex, serum albumin, estimated glomerular filtration rate, performance status, programmed cell death receptor ligand 1 expression in tumors, and treatment periods were evaluated as potential covariates for clearance. RESULTS: A total of 223 serum samples collected from 34 patients were available for analysis. The median (min-max) age and weight were 69 years (38-83 years) and 62.7 kg (36.8-80.5 kg), respectively. The mean (95% confidence interval) clearance estimate was 0.0064 L/h (0.0058-0.0070 L/h). The inclusion of the ALB level, estimated glomerular filtration rate, and treatment period significantly improved the model fit. CONCLUSIONS: A real-world nivolumab population PK model was developed using an opportunistic sampling strategy in Japanese patients with NSCLC. Further studies are warranted to characterize the exposure-response relationship and determine the optimal dosing regimens for these patients.

Evaluating the safety and efficiency of robotic dispensing systems.

BACKGROUND: Although automated dispensing robots have been implemented for medication dispensing in Japan, their effect is yet to be fully investigated. In this study, we evaluated the effect of automated dispensing robots and collaborative work with pharmacy support staff on medication dispensing. METHODS: A robotic dispensing system integrating the following three components was established: (1) automated dispensing robot (Drug Station®), which is operated by pharmacy support staff, (2) automated dispensing robot for powdered medicine (Mini DimeRo®), and (3) bar-coded medication dispensing support system with personal digital assistance (Hp-PORIMS®). Subsequently, we evaluated the incidences of dispensing errors and dispensing times before and after introducing the robotic dispensing system. Dispensing errors were classified into two categories, namely prevented dispensing errors and unprevented dispensing errors. The incidence of dispensing errors was calculated as follows: incidence of dispensing errors = total number of dispensing errors/total number of medication orders in each prescription. RESULTS: After introducing the robotic dispensing system, the total incidence of prevented dispensing errors was significantly reduced (0.204% [324/158,548] to 0.044% [50/114,111], p < 0.001). The total incidence of unprevented dispensing errors was significantly reduced (0.015% [24/158,548] to 0.002% [2/114,111], p < 0.001). The number of cases of wrong strength and wrong drug, which can seriously impact a patient's health, reduced to almost zero. The median dispensing time of pharmacists per prescription was significantly reduced (from 60 to 23 s, p < 0.001). CONCLUSIONS: The robotic dispensing system enabled the process of medication dispensing by pharmacist to be partially and safely shared with automated dispensing robots and pharmacy support staff. Therefore, clinical care for patients by pharmacists could be enhanced by ensuring quality and safety of medication.

Osteonecrosis of the Jaw Caused by Denosumab in Treatment-Naïve and Pre-Treatment with Zoledronic Acid Groups: A Time-to-Onset Study Using the Japanese Adverse Drug Event Report (JADER) Database.

BACKGROUND: Medication-related osteonecrosis of the jaw is a serious adverse event associated with bone-modifying agents, such as injectable bisphosphonate (zoledronic acid) and the anti-receptor activator of nuclear factor-κB ligand antibody (denosumab). OBJECTIVE: This study aims to evaluate and compare the time-to-onset profile for medication-related osteonecrosis of the jaw associated with denosumab between treatment-naïve (naïve group) and pre-treatment with zoledronic acid (post-zoledronic acid group) patients using the Japanese Adverse Drug Event Report database. METHODS: Medication-related osteonecrosis of the jaw was defined according to the Medical Dictionary for Regulatory Activities. The medication-related osteonecrosis of the jaw onset profiles were evaluated using the Weibull shape parameter and the log-rank test. RESULTS: The Japanese Adverse Drug Event Report database contains 632,409 reports published between April 2004 and March 2020. In the time-to-onset analysis, after extracting the combinations with complete information for the treatment start date and the medication-related osteonecrosis of the jaw onset date, 272 reports of the naïve group and 86 reports of the post-zoledronic acid group were analyzed. The median onset in the naïve and post-zoledronic acid groups was 487.0 (25-75%: 274.0-690.8) and 305.5 (25-75%: 158.3-508.5) days, respectively. Medication-related osteonecrosis of the jaw occurred earlier in the post-zoledronic acid group than in the naïve group, and the log-rank test demonstrated a significant difference in their time transitions (p < 0.0001). CONCLUSIONS: The results indicated a risk of medication-related osteonecrosis of the jaw in naïve and post-zoledronic acid groups and a shorter onset time in the latter than in the former. Thus, healthcare professionals should take the early risk of medication-related osteonecrosis of the jaw into account when switching patients from zoledronic acid to denosumab treatment.

Pharmacist-Urologist Collaborative Management Improves Clinical Outcomes in Patients With Castration-Resistant Prostate Cancer Receiving Enzalutamide.

Background: Enzalutamide is useful for the treatment of castration-resistant prostate cancer (CRPC). Despite its usefulness, adverse events (AEs) sometimes force patients to discontinue treatment. To maximize patient care, we developed an ambulatory care pharmacy practice that allows collaboration between a pharmacist and urologist to manage patients with CRPC receiving enzalutamide. In this study, we investigated the efficacy of this collaborative management. Methods: A retrospective chart review of 103 patients with CRPC receiving enzalutamide in our hospital between May 2014 and December 2020 was performed. Our collaborative management was implemented in October 2016. Before being examined by urologists, patients visited the oncology pharmacy consultation room for a face-to-face consultation, wherein the oncology pharmacists assessed factors such as adherence to enzalutamide, any AEs and their grades, and provided their suggestions to the urologists. The time to enzalutamide discontinuation and prostate-specific antigen progression were compared between patients who started enzalutamide before (n = 41) and after (n = 62) the implementation of the collaborative management. A multivariate Cox regression analysis was performed to analyze the factors associated with enzalutamide discontinuation. Results: After implementing collaborative management, the pharmacists had 881 patient consultations. Among the 476 suggestions from pharmacists, 345 were accepted by urologists. The most frequent suggestion was supportive care in enzalutamide treatment (224 suggestions). Multivariate analysis showed that collaborative management [hazard ratio (HR) 0.53, 95% confidence interval (CI) 0.31-0.89, p = 0.017] and higher prostate-specific antigen (PSA; HR 2.41, 95% CI 1.36-4.28, p = 0.003) were significantly associated with enzalutamide discontinuation. The median time to discontinuation (18.9 vs. 7.6 months, p = 0.012), time to discontinuation due to AEs (not reached in both groups, p = 0.001), and time to PSA progression (13.3 vs. 5.8 months, p = 0.002) were all significantly longer in the after group. Conclusions: We implemented a pharmacist-urologist collaborative management program for outpatients with CRPC receiving enzalutamide. The results revealed that collaborative management was useful for prolonging the time to enzalutamide discontinuation.

Association between 25-hydroxyvitamin D levels and COVID-19 severity.

BACKGROUND AND AIMS: Despite reports on the impact of vitamin D status on coronavirus disease 2019 (COVID-19) severity, the association between low vitamin D status and severe COVID-19 remains unclear. Moreover, researchers have not determined the aforementioned association in Japanese patients. This study aimed to investigate the association between 25-hydroxyvitamin D [25(OH)D] levels and COVID-19 severity in Japanese patients. METHODS: This retrospective observational study included 117 consecutive patients with COVID-19 admitted to the Kobe City Medical Center General Hospital between October 01, 2020, and January 31, 2021. We measured the serum 25(OH)D levels using blood specimens collected within 5 days of hospital admission using liquid chromatography-tandem mass spectrometry. RESULTS: There were 21 (17.9%), 73 (62.4%), 19 (16.2%) and 4 (3.4%) patients with severe deficiency (<10 ng/mL), deficiency (10-<20 ng/mL), insufficiency (20-<30 ng/mL), and sufficiency (≥30 ng/mL) of vitamin D, respectively. In univariate logistic regression analyses, lower serum 25(OH)D levels [odds ratio (OR) 1.18 per 1 ng/mL decrease, 95% confidence interval (CI) 1.04-1.33, p = 0.007] were significantly associated with invasive mechanical ventilation (IMV) or death. In a multivariate logistic regression analysis, low serum 25(OH)D levels [OR 1.22 per 1 ng/mL decrease, 95% CI 1.06-1.40, p = 0.005] were significantly associated with IMV or death. The cut-off value of serum 25(OH)D levels was 10.4 ng/mL, calculated by the receiver operating characteristic curve to detect the requirement for IMV or death. CONCLUSIONS: To the best of our knowledge, this is the first study to assess the association between vitamin D status and COVID-19 severity in Japanese patients. Low serum 25(OH)D level was detected as an independent risk factor for severe COVID-19 among Japanese patients.

Risk factors of proteinuria and potentially protective effect of renin-angiotensin system inhibitors in patients with renal cell carcinoma receiving axitinib.

PURPOSE: Patients receiving vascular endothelial growth factor-tyrosine kinase inhibitors are at a risk of developing proteinuria. Renin-angiotensin system (RAS) inhibitors exert renoprotective effects and might reduce proteinuria risk in these patients. We investigated the risk factors for and protective effect of RAS inhibitors against proteinuria in patients with renal cell carcinoma (RCC) receiving axitinib. METHODS: We retrospectively reviewed the medical records of patients with RCC receiving axitinib at Kobe City Medical Center General Hospital between September 2012 and October 2020. Patients with proteinuria ≥ 2+ at baseline were excluded. The patients were categorized into RAS inhibitor user, non-RAS inhibitor user, and non-user groups. The severity of proteinuria was graded based on the Common Terminology Criteria for Adverse Events, version 5.0. A multivariate Cox proportional hazards model was employed to identify the risk factors for developing grade ≥ 2 proteinuria. RESULTS: Among 42 patients, 28 received antihypertensive drugs at baseline. Among these, 17 and 11 patients were in the RAS inhibitor and non-RAS inhibitor user groups, respectively. Twenty-three patients (54.8%) developed grade ≥ 2 proteinuria. The multivariate analysis revealed that the non-RAS inhibitor user group (P = 0.001) and patients with pre-existing grade 1 proteinuria (P = 0.022) were significantly associated with the development of grade ≥ 2 proteinuria, whereas the RAS inhibitor user group was not significantly associated with it. CONCLUSION: In patients with RCC receiving axitinib, pre-existing proteinuria and non-RAS inhibitor use were significantly associated with grade ≥ 2 proteinuria development. Our preliminary data should be confirmed by further studies.

Risk Factors of Proteinuria in Patients with Hepatocellular Carcinoma Receiving Lenvatinib.

Proteinuria is one of the most frequently reported adverse events leading to the discontinuation of lenvatinib treatment in patients with advanced hepatocellular carcinoma (HCC). However, there are no reports regarding the risk factors of proteinuria in patients with HCC or patients receiving lenvatinib. We retrospectively reviewed the medical records of patients with HCC receiving lenvatinib at the Kobe City Medical Center General Hospital between April 2018 and December 2020. The severity of proteinuria was graded based on the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. A multivariate Cox proportional hazards model was employed to identify the risk factors of developing grade ≥2 proteinuria. Among the 37 patients included, 3 patients had grade-1 proteinuria at baseline and 10 patients had estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 at baseline. Grades 1, 2, and 3 proteinuria were observed in 15 (40.5%), 10 (27.0%), and 2 (5.4%) patients, respectively, during lenvatinib treatment. The median value of eGFR was significantly lower in patients who developed grade ≥2 proteinuria than those with grade ≤1 proteinuria (59.6 vs. 78.1 mL/min/1.73 m2, p = 0.045). Multivariate analysis revealed that pre-existing proteinuria at baseline (hazard ratio (HR), 9.72; 95% confidence interval (CI), 1.29-52.21; p = 0.030), and eGFR <60 mL/min/1.73 m2 at baseline (HR, 4.49; 95% CI, 1.32-16.07; p = 0.017) were significantly associated with developing grade ≥2 proteinuria. These patients should be monitored carefully, and our preliminary data should be confirmed by further studies.

Risk evaluation of denosumab and zoledronic acid for medication-related osteonecrosis of the jaw in patients with bone metastases: a propensity score-matched analysis.

PURPOSE: This study evaluated the risk of medication-related osteonecrosis of the jaw (MRONJ) in patients with cancer who received denosumab or zoledronic acid (ZA) for treating bone metastasis. METHODS: The medical records of patients were retrospectively reviewed. Patients who did not undergo a dental examination at baseline were excluded. The primary endpoint was a comparison of the risk of developing MRONJ between the denosumab and ZA groups. Propensity score matching was used to control for baseline differences between patient characteristics and compare outcomes for both groups. RESULTS: Among the 799 patients enrolled, 58 (7.3%) developed MRONJ. The incidence of MRONJ was significantly higher in the denosumab group than in the ZA group (9.6% [39/406] vs. 4.8% [19/393], p = 0.009). Multivariate Cox proportional hazards regression analysis revealed that denosumab treatment (hazard ratio [HR], 2.89; 95% confidence interval [CI], 1.65-5.25; p < 0.001) and tooth extraction after starting ZA or denosumab (HR, 4.26; 95% CI, 2.38-7.44; p < 0.001) were significant risk factors for MRONJ. Propensity score-matched analysis confirmed that the risk of developing MRONJ was significantly higher in the denosumab group than in the ZA group (HR, 2.34; 95% CI, 1.17-5.01; p = 0.016). CONCLUSION: The results of this study suggest that denosumab poses a significant risk for developing MRONJ in patients treated for bone metastasis, and thus these patients require close monitoring.

[Consideration on Expiration Days Setting for the Introduction of Drug Vial Optimization].

When drug vial optimization(DVO)is implemented, the medical facilities will be forced to bear the cost of the divided- use drugs not used up within the expiration date. We determined the expiration days to use up the residual drugs in the vial within the expiration period. The cost of discarded drugs was calculated from the prescription data of anticancer drugs. We estimated the discarded drug volumes when the expiration period was 0, 1, 2, 7, 8, 14, or 28 days for each liquid anticancer drug. When the expiration period was 7 days, the discarded amount was equivalent to 5.5% of the amount on 0-day expiration period. Only one drug with a 28 day expiration period had to be discarded. When the expiration period is 1 to 2 days, drugs are always discarded and the medical facilities must bear the cost of the wasted drugs. If the expiration period is 7 days or more, most of the medicine will not be discarded. To introduce DVO to medical facilities without economic loss, extending the expiration period of DVO must be considered.

Analysis of Drug-Induced Gastrointestinal Obstruction and Perforation Using the Japanese Adverse Drug Event Report Database.

Drug-induced gastrointestinal obstruction (DIGO) and gastrointestinal perforation (DIGP) may be the result of gastrointestinal hypomotility and severe constipation, which may lead to potentially fatal complications of bowel ischemia, sepsis and perforation. We evaluated the onset profile of DIGs (DIGO and DIGP) associated with prescription drugs by analyzing data in the Japanese Adverse Drug Event Report (JADER) database. We selected 161 DIG-related drugs and categorized them into 19 classes based on the Anatomical Therapeutic Chemical (ATC) Classification System. Finally, we focused on 58 drugs and conducted subsequent analyses for the time-to-onset and outcomes. We extracted 79 preferred terms (PTs) with the strings "ileus," "stenosis," "obstruction," "obstructive," "impaction," "perforation," "perforated," "hypomotility," and "intussusception" from the Standardized Medical Dictionary for Regulatory Activities (MedDRA) Queries (SMQs) of SMQ20000104: gastrointestinal perforation, ulcer, hemorrhage, obstruction non-specific findings/procedures; SMQ20000105: gastrointestinal obstruction; and SMQ20000107: gastrointestinal perforation. Among the 667, 729 reports in the JADER database submitted between April 2004 and November 2020, we identified 11,351 occurrences of DIGs. The reporting odds ratios (RORs) (95% confidence interval) of "barium sulfate containing X-ray media," "drugs for treatment of hyperkalemia and hyperphosphatemia," and "oral bowel cleanser" were 142.0 (127.1-158.6), 25.8 (23.1-28.8), and 29.7 (24.8-35.6), respectively. The median number of days (interquartile range) until the onset of an adverse event caused by each drug category was as follows: barium sulfate containing X-ray contrast media [2.0 (1.0-3.0)], diazepines, oxazepines, thiazepines, and oxepines [8.0 (8.0-18.5)], drugs for treatment of hyperkalemia and hyperphosphatemia [29.0 (8.0-55.0)], non-selective monoamine reuptake inhibitors [19.0 (7.0-47.5)], and oral bowel cleanser [0.0 (0.0-0.0)]. Depending on the drug, the time to onset of side effects ranged from days to several months. Our results highlighted the need to perform detailed monitoring of each drug for possible association with DIGs, which might otherwise have fatal consequences.

Safety and efficacy evaluation of low-dose trimethoprim-sulfamethoxazole for prophylaxis of Pneumocystis pneumonia in HIV uninfected patients undergoing hemodialysis: a retrospective observational study.

BACKGROUND: Pneumocystis pneumonia (PCP) is a potentially life-threatening infection. Trimethoprim-sulfamethoxazole (TMP-SMX) is considered as the first regimen for PCP prophylaxis according to several guidelines. The recommended prophylactic dose of TMP-SMX has been determined based on patients with normal renal function, but the appropriate dosage for patients undergoing hemodialysis is unknown. The aim of this study was to investigate the efficacy and safety of low-dose TMP-SMX in patients undergoing hemodialysis. METHODS: HIV-uninfected adult patients who were undergoing hemodialysis and administered TMP-SMX for PCP prophylaxis, were included, and divided into standard-dose (≥6 single strength (SS, TMP-SMX 80 mg/400 mg tablets/week) and low-dose groups (< 6 SS tablets/week). The endpoints were cumulative incidence of PCP and cumulative discontinuation rate of TMP-SMX due to adverse events. For comparison of the groups, we employed the chi-squared test for categorical variables and the Mann-Whitney U test for continuous variables. Risk factors for the endpoints were evaluated using the Cox Fine and Gray method. RESULTS: The median age of the 81 patients included in the study was 67 years (IQR: 60-76 years), and 52 patients (64.2%) were men. No patients in either group developed PCP during the observation period. The yearly cumulative incidence of discontinuation was 12.1% (95% confidence interval [CI]: 0.027-0.29) in the low-dose group and 35.6% (95% CI: 0.20-0.52) in the standard-dose group (P = 0.019). The adjusted hazard ratio of the low-dose group compared to standard-dose group was 0.18 (95% CI: 0.04-0.86, P = 0.032). CONCLUSIONS: None of the study patients developed PCP, and the cumulative discontinuation rate of TMP-SMX due to adverse events was significantly lower in the low-dose group compared to that in the standard-dose group (P = 0.032). These results indicate that low-dose TMP-SMX is an appropriate regimen to maintain a balance between PCP prophylaxis and prevention of adverse events due to TMP-SMX administration. These findings can guide health care professionals to determine TMP-SMX dosage when considering PCP prophylaxis for patients undergoing hemodialysis.

Population pharmacokinetics of favipiravir in patients with COVID-19.

The antiretroviral drug favipiravir (FPV) inhibits RNA-dependent RNA polymerase. It has been developed for the treatment of the novel coronavirus (severe acute respiratory syndrome coronavirus 2) infection disease, coronavirus disease 2019 (COVID-19). However, its pharmacokinetics in patients with COVID-19 is poorly understood. In this study, we measured FPV serum concentration by liquid chromatography-tandem mass spectrometry and conducted population pharmacokinetic analysis. A total of 39 patients were enrolled in the study: 33 were administered FPV 1600 mg twice daily (b.i.d.) on the first day followed by 600 mg b.i.d., and 6 were administered FPV 1800 mg b.i.d. on the first day followed by 800 mg or 600 mg b.i.d. The median age was 68 years (range, 27-89 years), 31 (79.5%) patients were men, median body surface area (BSA) was 1.72 m2 (range, 1.11-2.2 m2 ), and 10 (25.6%) patients required invasive mechanical ventilation (IMV) at the start of FPV. A total of 204 serum concentrations were available for pharmacokinetic analysis. A one-compartment model with first-order elimination was used to describe the pharmacokinetics. The estimated mean clearance/bioavailability (CL/F) and distribution volume/bioavailability (V/F) were 5.11 L/h and 41.6 L, respectively. Covariate analysis revealed that CL/F was significantly related to dosage, IMV use, and BSA. A simulation study showed that the 1600 mg/600 mg b.i.d. regimen was insufficient for the treatment of COVID-19 targeting the 50% effective concentration (9.7 µg/mL), especially in patients with larger BSA and/or IMV. A higher FPV dosage is required for COVID-19, but dose-dependent nonlinear pharmacokinetics may cause an unexpected significant pharmacokinetic change and drug toxicity. Further studies are warranted to explore the optimal FPV regimen.

Analysis of chemotherapy-induced peripheral neuropathy using the Japanese Adverse Drug Event Report database.

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse event associated with several antineoplastic drugs; however, the precise risks and time course of reactions of particular drugs are not clearly understood. The aim of this study was to evaluate the relationship between anticancer agents and CIPN development using data from the Japanese Adverse Drug Event Report (JADER) database and to characterize the time-to-onset and outcomes of CIPN. Chemotherapy-induced peripheral neuropathy was defined using the Medical Dictionary for Regulatory Activities preferred terms. Disproportionality analysis was performed by calculating the reporting odds ratio (ROR) with 95% confidence interval for signal detection. Data of nine Anatomical Therapeutic Chemical (ATC) drug categories correlated with CIPN development, in addition to the data of the time-to-onset and outcomes. Among 622,289 reports in the JADER database from April 2004 to March 2020, there were 1883 reports of adverse events corresponding to peripheral neuropathy. The ROR (95% confidence interval) for vinblastine, sorbent-based paclitaxel (sb-PTX), oxaliplatin, and bortezomib was 20.4 (12.5-33.4), 13.6 (11.9-15.7), 26.2 (23.6-29.1), and 30.8 (26.6-35.8), respectively. The median duration (interquartile range) to CIPN development after the administration of vinca alkaloids and analogues, taxanes, platinum compounds, and monoclonal antibodies was 11.0 (5.0-46.5), 22.5 (6.0-82.5), 22.0 (6.0-68.5), and 32.5 (11.3-73.8) days, respectively. The median duration (interquartile range) of sb-PTX and nanoparticle albumin-bound (nab)-PTX was 35.0 (7.0-94.0) and 5.5 (3.0-29.3) days, respectively. Our analysis of records in the JADER database revealed several drugs associated with a high risk for CIPN development. In particular, the development of CIPN after vinca alkaloid administration should be closely monitored for 2 weeks after administration. CIPN caused by nab-PTX showed significantly faster onset than that by sb-PTX. Patients who receive taxanes or monoclonal antibodies often do not show an improvement; accordingly, early treatment is required.