Risk factors indicating immune-related adverse events with combination chemotherapy with immune checkpoint inhibitors and platinum agents in patients with non-small cell lung cancer: a multicenter retrospective study.

PURPOSE: Immune checkpoint inhibitors (ICI) ushered in a new era for the treatment of non-small cell lung cancer (NSCLC). However, they carry the risk of immune-related adverse events (irAEs). Recently, various studies have been conducted on the predictive factors for irAEs, but there are no reports focusing only on ICI plus platinum agents. The present study aimed to identify the risk factors for irAEs due to ICI combined with platinum-based induction immunochemotherapy in NSCLC patients, focusing only on the period of combined therapy and excluding the period of ICI maintenance therapy. METHODS: This retrospective study included 315 NSCLC patients who started ICI combined with platinum-based chemotherapy treatment at 14 hospitals between December 2018 and March 2021. A logistic regression analysis was used to explore the predictive factors. RESULTS: Fifty patients (15.9%) experienced irAEs. A multivariate analysis revealed that squamous cell carcinoma (P = 0.021; odds ratio [OR]: 2.30; 95% confidence interval [Cl]: 1.14-4.65), anti-programmed death 1 antibody (anti-PD-1) plus anti-cytotoxic T-lymphocyte antigen-4 antibody (anti-CTLA-4) regimens (P < 0.01; OR: 22.10; 95% Cl: 5.60-87.20), and neutrophil-to-lymphocyte rate (NLR) < 3 (P < 0.01; OR: 2.91; 95% Cl: 1.35-6.27) were independent predictive factors for irAEs occurrence. CONCLUSION: Squamous cell carcinoma, anti-PD-1 plus anti-CTLA-4 regimens, and NLR < 3 may be predictive factors for the occurrence of irAEs due to induction immunochemotherapy in patients with NSCLC. By focusing on the potential risk of irAEs in patients with these factors, irAEs can be appropriately managed from an early stage.

Palonosetron versus Granisetron in Combination with Aprepitant and Dexamethasone for the Prevention of Chemotherapy-Induced Nausea and Vomiting after Moderately Emetogenic Chemotherapy: A Single-Institutional Retrospective Cohort Study.

The triplet antiemetic regimen is administered to prevent chemotherapy-induced nausea and vomiting (CINV) after moderately emetogenic chemotherapy (MEC). However, the superiority of palonosetron over first-generation 5-hydroxytryptamine-3 receptor antagonists in triplet antiemetic therapy remains unclear. In this study, we evaluated the efficacy of palonosetron (PALO) and granisetron (GRA) in triplet antiemetic therapy for CINV. This study included 267 patients who received MEC at our hospital between April 2017 and September 2020. Patients were pretreated with antiemetic therapy comprising PALO or GRA and dexamethasone on day 1 and aprepitant on days 1-3. We evaluated the rate of complete response (CR) (i.e., no vomiting and no use of rescue medication) in the acute phase (0-24 h), delayed phase (24-120 h), and overall phase (0-120 h) after first-cycle chemotherapy. Furthermore, multivariate analysis was conducted to identify risk factors for non-CR. The rate of CR in the overall and delayed phases was significantly higher in the PALO group (91.9 and 91.9%, respectively) than in the GRA group (74.1 and 75.5%, respectively). In the acute phase, the incidence was not different between the GRA and PALO groups (96.5 and 99.2%, respectively). Multivariate analysis revealed that female sex and the use of GRA were risk factors for non-CR. Subgroup analysis revealed the superiority of PALO over GRA in female patients, but not in male patients. In conclusion, PALO was more effective than GRA in triplet antiemetic therapy in preventing CINV during MEC, especially for female patients.

Clinical pharmacokinetics of oxaliplatin in a hemodialysis patient with advanced gastric cancer.

We administered FOLFOX (oxaliplatin (L-OHP) plus infusional 5-fluorouracil (5-FU) and leucovorin) to an hemodialysis (HD) patient with advanced gastric cancer (AGC), and investigated pharmacokinetics (PKs) and dialyzability of L-OHP. The patient was a 54-year-old Japanese man with a diagnosis of inoperable AGC. FOLFOX was instituted 3 h prior to the start of a 4 h HD period with the L-OHP and 5-FU doses reduced by 50% for the first cycle, and 30% reduced dose was administered for the second cycle. We performed an analysis of the PKs of L-OHP during these two cycles. Volume of distribution and area under the curve of the 30% reduced L-OHP dose were 56.7 L and 30.0 µg·h/mL, respectively. A dose reduction of L-OHP by 30%-50% may be advisable for the initial administration, given the need for careful administration of chemotherapy in HD patients, with particular attention to the development of hematological toxicities and neuropathy.

Vancomycin pharmacokinetics in critically ill patients receiving continuous haemodiafiltration with a polyethyleneimine-coated polyacrylonitrile membrane.

WHAT IS KNOWN AND OBJECTIVE: We investigated the elimination efficiency and pharmacokinetics (PK) parameters of vancomycin (VCM) in patients undergoing continuous haemodiafiltration (CHDF) using a polyethyleneimine-coated polyacrylonitrile membrane (AN69ST) for dosage adjustment. METHODS: We conducted a retrospective study of CHDF patients treated with VCM from December 2017 to August 2019. We calculated PK parameters of VCM and determined the 24-hour dose required to maintain the target trough concentration of VCM (VCM_trough ). RESULTS AND DISCUSSION: The average (95% CI) volume of distribution and total clearance of VCM were 75.5 L (63.7-87.3 L) and 1.84 L/h (1.38-2.30 L/h), respectively, and the elimination rate constant and half-life were 0.026/h (0.017-0.034/h) and 31.2 h (22.8-39.5 h), respectively. The average AN69ST clearance of VCM (CL_CHDF ) was 0.69 L/h (0.52-0.86 L/h). The estimated average doses required to maintain VCM_trough of 10, 15 and 20 µg/mL were 623.1 mg (379.8-866.4 mg), 934.6 mg (569.7-1299.5 mg) and 1246.2 mg (759.6-1732.8 mg), respectively. WHAT IS NEW AND CONCLUSION: The PK of VCM and CL_CHDF of AN69ST were clarified. These results suggest that it is possible to adjust the dose of VCM in using AN69ST, which efficiently removes cytokines, and contributes to improvement of serious infections.

[A Case of Advanced Esophageal Cancer Treated with Nedaplatin in a Patient Undergoing Maintenance Hemodialysis].

Herein, we investigated the pharmacokinetic (PK) profile of nedaplatin (cis-diamine-glycolateplatinum; CDGP) in a hemodialysis (HD) patient with advanced esophageal squamous cell carcinoma (ESCC) by administering the CDGP immediately prior to HD. Our patient was treated with CDGP (45 mg/m2 for a total dose of 60.2 mg) and 5-fluorouracil (560 mg/m2 for a total dose of 750 mg) before initiating HD. The total platinum (Pt) concentration (Pt_total) and free Pt concentration (Pt_free) 2 h after completion of HD were 0.4 µg/mL and 0.3 µg/mL, respectively. The removal rates of Pt_total and Pt_free by the dialyzer were 76.5% and 84.6%, respectively. Twenty-four hours after CDGP administration, the Pt_free was below the detection limit of the method of analysis. Pt_free within the range of the recommended CDGP target AUC0-24 was 8-10 µg/mL•h, the AUC0-24 of Pt_total and Pt_free were 16.5 µg/mL•h and 8.8 µg/mL•h, respectively. We conclude that HD should be performed after the end of CDGP infusion as part of the CDGP chemotherapy regimen for HD patients with ESCC, and suggest that HD is effective for obtaining a PK profile of CDGP similar to patients with normal renal function.

[Evaluation of Intervention by an Antimicrobial Stewardship Team for Patients with Bacteremia].

In this study, antimicrobial stewardship team (AST) intervention was evaluated by comparing patient outcomes and consumption of broad-spectrum antibiotics [carbapenem antibiotics and tazobactam/piperacillin (TAZ/PIPC)] before and after the intervention. There was no fluctuation in the consumption rate of carbapenem, TAZ/PIPC and other antibiotics, but there was a decreased annual consumption of antibiotics after AST intervention compared to before intervention. For the carbapenems, antimicrobial use density (AUD) of meropenem (MEPM) was highest in both periods, at 20.1 and 20.4 before and after AST intervention, respectively, with no significant change after AST intervention. However, the days of therapy (DOT) for MEPM were 27.4 and 24.8 d, respectively, with a decreasing trend after AST intervention. AUD and DOT for TAZ/PIPC after AST intervention were 6.5 and 8.1 d, respectively, which were lower than the pre-intervention values. Rapid identification of the causative strain enables early de-escalation and may improve the economics of antibiotic use, but there was no difference from before to after AST intervention. Compared with before and after strain identification, the carbapenem administration rate after AST intervention was significantly lower than the pre-intervention rate (p<0.01). There was no difference in 28-day mortality and treatment period before and after AST intervention, and there were no differences in outcomes such as resolution of bacteremia, mortality, exacerbation and no change from before to after AST intervention. Based on these results, we suggest that AST intervention can reduce consumption of antibiotics without altering patient outcomes.

Pharmacokinetics and pharmacodynamics of daptomycin in a clinical setting.

We investigated achievement of a target 24-h area under the concentration-time curve to minimum inhibitory concentration ratio (AUC/MIC) ≥666 and the factors influencing this ratio in patients who received daptomycin (DAP) for infectious disease treatment in a clinical setting. The target AUC/MIC was obtained in 6 patients (35.3%) at a 4-6 mg/kg dose (Group_4-6 mg/kg) and in 4 (18.2%) at a >6 mg/kg dose (Group_>6 mg/kg). There was a significant difference in clearance of DAP (CL_DAP) between these groups, but no other difference in characteristics. Multiple linear regression analysis was performed for prediction of AUC ≥666 based on patient factors and the presence or absence of sepsis. In a stepwise analysis, serum creatinine (SCr) was a significant predictor of AUC, but this parameter explained only 13% of the variance in achievement of the target AUC. These results show that the target AUC/MIC may or may not be achieved at the doses used in Group_4-6 mg/kg and Group_>6 mg/kg. Receiver operating characteristic analysis suggested that a CL_DAP >0.450 L/hr may lead to failure to reach the target AUC/MIC. Therefore, regardless of dose, the efficacy of DAP should be monitored closely to prevent failure of infectious disease treatment, particularly because therapeutic drug monitoring of DAP is limited by difficulty measuring the DAP serum concentration at many medical facilities. Our findings are preliminary, and a further study is required to identify factors that increase CL_DAP and to enable dose adjustment of DAP.

Preparation and Evaluation of a Modified Mohs Paste Mixed with Zinc Oxide 10% Topical Oil-Based Ointment.

BACKGROUND: The skin fixative used in Mohs chemosurgery contains zinc chloride and is referred to as Mohs paste (MP). However, MP shows a remarkable change in rheological characteristics after its preparation. OBJECTIVE: To prepare an MP with stable rheological characteristics, we prepared a modified MP (mMP) using zinc oxide 10% single ointment (Zn_ointment), which is an oil-based ointment. METHODS: We evaluated mMP by determining its rheological characteristics, depth of tissue fixation, and observation of the tissue surface after treatment. RESULTS: The viscosity of mMP increased after three months. However, the treatment-dependent viscosity of mMP could be obtained by mixing with glycerin. The viscosity and spreadability of mMP_3mth, which was three months after preparation, were 1992.0 ± 376.5 Pa·s and 2.1 ± 0.1 cm, respectively. In contrast, the viscosity and spreadability of MP mixed with glycerin were 436.9 ± 0.0 Pa·s and 2.8 ± 0.0 cm, respectively. The fixed invasion depth of MP was significantly higher than that of mMP (p < 0.05). CONCLUSION: This study of a mixture of MP and Zn_ointment showed that the viscosity of mMP could be adjusted with glycerin. Also, the tissue fixation of mMP progressed slowly compared with that of MP. This finding suggests that mMP is effective and safe for Mohs treatment.

Population pharmacokinetics of teicoplanin in hospitalized elderly patients using cystatin C as an indicator of renal function.

OBJECTIVE: Serum cystatin C (CysC) has recently been proposed as an alternative marker to serum creatinine (SCR) for estimating renal clearance. In the present study, we performed a population pharmacokinetic analysis of teicoplanin (TEIC), which is mainly eliminated through the kidneys, using CysC as a predictor for renal clearance. METHODS: Thirty-six patients with MRSA infections who were administrated to the National Hospital Organization Beppu Medical Center between January 2012 and December 2013 were enrolled and gave 123 sets of blood TEIC concentration data. Renal clearance was estimated by the Hoek equation using CysC, by creatinine clearance predicted by the Cockcroft-Gault equation using SCR, or directly by CysC. One compartment open model with inter-individual variabilities for renal clearance and the volume of distribution as well as an additional residual error model was used to estimate population pharmacokinetic parameters for TEIC. RESULTS: The model with the best predictability was that with CysC as a predictor for renal clearance; it showed better significance than the models using estimated the glomerular filtration rate by the Hoek equation or CLcr. The final model was as follows: CL (L/hr) = 0.510 × (CysC/1.4)-0.68 × Total body weight/600.81, omega (CL) = 19.8% CV, VC (L) = 78.1, omega (V) = 42.7% CV. CONCLUSION: The present results show the usefulness of CysC to more accurately predict the pharmacokinetics of drugs mainly eliminated through the kidneys, such as TEIC. However, since the sample size in this study was relatively small, further investigations on renal clearance predictability using CysC are needed.

Distribution and Molecular Characterization of Acinetobacter baumannii International Clone II Lineage in Japan.

Multidrug-resistant (MDR) Acinetobacter spp. have been globally disseminated in association with the successful clonal lineage Acinetobacter baumannii international clone II (IC II). Because the prevalence of MDR Acinetobacter spp. in Japan remains very low, we characterized all Acinetobacter spp. (n = 866) from 76 hospitals between October 2012 and March 2013 to describe the entire molecular epidemiology of Acinetobacter spp. The most prevalent species was A. baumannii (n = 645; 74.5%), with A. baumannii IC II (n = 245) accounting for 28.3% of the total. Meropenem-resistant isolates accounted for 2.0% (n = 17) and carried ISAba1-blaOXA-23-like (n = 10), blaIMP (n = 4), or ISAba1-blaOXA-51-like (n = 3). Multilocus sequence typing of 110 representative A. baumannii isolates revealed the considerable prevalence of domestic sequence types (STs). A. baumannii IC II isolates were divided into the domestic sequence type 469 (ST469) (n = 18) and the globally disseminated STs ST208 (n = 14) and ST219 (n = 4). ST469 isolates were susceptible to more antimicrobial agents, while ST208 and ST219 overproduced the intrinsic AmpC ß-lactamase. A. baumannii IC II and some A. baumannii non-IC II STs (e.g., ST149 and ST246) were associated with fluoroquinolone resistance. This study revealed that carbapenem-susceptible A. baumannii IC II was moderately disseminated in Japan. The low prevalence of acquired carbapenemase genes and presence of domestic STs could contribute to the low prevalence of MDR A. baumannii A similar epidemiology might have appeared before the global dissemination of MDR epidemic lineages. In addition, fluoroquinolone resistance associated with A. baumannii IC II may provide insight into the significance of A. baumannii epidemic clones.

Mechanism Underlying Linezolid-induced Thrombocytopenia in a Chronic Kidney Failure Mouse Model.

OBJECTIVE: To investigate the relationship between renal function and linezolid (LZD)-induced thrombocytopenia and elucidate the underlying mechanism using a chronic renal disease (CRD) mouse model. MATERIALS AND METHODS: CRD was induced in 5-week-old male Institute of Cancer Research (ICR) mice by 5/6 nephrectomy. After this procedure, LZD (25 and 100 mg/kg) was administered intraperitoneally once every day for 28 days. Platelet counts, white blood cell (WBC) counts, and hematocrit (HCT) levels were measured every 7 days. 2-14C-thymidine (0.185 MBq) was administrated intravenously to LZD-administered mice to evaluate the thymidine uptake ability of bone marrow. RESULTS: Platelet counts were significantly lower in the LZD-administered CRD group than in the LZD-nonadministered groups at 14, 21, and 28 days (P < 0.05); however, these changes were not observed in LZD-administered mice with normal renal function, regardless of the duration of LZD administration. No significant changes were observed in WBC counts or HCT levels in any LZD-administered CRD mouse. Moreover, radioactive levels in bone marrow were not significantly different in each group. CONCLUSIONS: These results indicate that LZD-induced decreases in platelet counts were enhanced by renal impairment in vivo, suggesting that LZD-induced thrombocytopenia is not caused by nonimmune-mediated bone marrow suppression.

Pharmacokinetics of linezolid during continuous hemodiafiltration: A case report.

The pharmacokinetics of linezolid clearance (CLLZD) during continuous hemodiafiltration (CHDF) has not been comprehensively analyzed. Here, we examined CLLZD by CHDF in a patient with septic shock and disseminated intravascular coagulation due to methicillin-resistant Staphylococcus aureus. The extraction ratio of LZD by CHDF was 22.6%, and the protein-binding rate was 17.9% ± 7.7%. In addition, it was determined that the calculated total body clearance of LZD was 30.2 mL/min, plasma elimination half-life was 8.66 h, and the CLLZD by the dialyzer used for CHDF was 23.0 mL/min. From the obtained pharmacokinetics, the CLLZD of patients continuing CHDF was estimated to be approximately half of the reported CLLZD for healthy subjects. In addition, the LZD concentration of the sepsis patient who underwent CHDF remained higher than the minimum inhibitory concentration and was similar to the LZD concentrations reported in normal renal function patients. Although further studies are warranted, when LZD is administered to patients treated with CHDF, the present findings suggest that dose regulation is not required.

Evaluation of pharmacokinetics and the stability of daptomycin in serum at various temperatures.

BACKGROUND: Daptomycin exhibits concentration-dependent antibacterial activity. By monitoring daptomycin serum concentrations, clinicians may be able to predict the effectiveness of treatments for infections more accurately. However, it has been reported that daptomycin concentrations in plasma samples stored at -20°C decrease approximately 25% after 4 weeks. The aim of this study was to evaluate the stability of daptomycin in serum at various temperatures. METHODS: Daptomycin serum samples were prepared and stored at different temperatures. The stability of daptomycin under various conditions was evaluated by sequential measurements of concentration. RESULTS: Although the loss of concentration of daptomycin in serum samples stored in freezers (-80°C and -20°C) was less than 10% after 168days (6 months), the concentrations in samples stored in a refrigerator (4°C) decreased by more than 70% over the same period. Furthermore, daptomycin concentrations in serum samples stored at close to body temperature (35°C, 37°C, and 39°C) decreased by more than 50% after only 24h. CONCLUSIONS: The results of the present study demonstrate that the measurement of serum concentrations of daptomycin needs to be performed rapidly. Furthermore, the degradation of daptomycin in serum may be involved in its elimination from the living body.

Risk Factors Associated with Cisplatin-Induced Nephrotoxicity in Patients with Advanced Lung Cancer.

Cisplatin (CDDP) combination chemotherapy is widely administered to patients with advanced lung cancer. The dose depends on multiple factors, including whether the tumor is non-small-cell lung cancer (NSCLC) or small-cell lung cancer (SCLC). Although efficacy is limited by cisplatin-induced nephrotoxicity (CIN), little is known about the risk factors for this complication. The aim of this study was to identify the risk factors for CIN in patients with advanced lung cancer, both NSCLC and SCLC. We retrospectively reviewed clinical data for 148 patients who underwent initial chemotherapy including CDDP ≥50 mg/m2 per patient per day for the first course at Kyushu Medical Center between October 2010 and September 2013. All data were collected from the electronic medical record system. Nephrotoxicity was defined as an increase in serum creatinine concentration of at least grade 2 during the first course of CDDP chemotherapy, as described by the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. CIN was observed in nine patients. Univariate analysis revealed that cardiac disease and lower baseline serum albumin (Alb) values conferred a higher risk of nephrotoxicity (p<0.05). The cut-off value of Alb was 3.8 g/dL, calculated by receiver operating characteristics (ROC) curves. Multivariable logistic regression analysis revealed that cardiac disease (odds ratio=11.7; p=0.002) and hypoalbuminemia (odds ratio=6.99 p=0.025 significantly correlated with nephrotoxicity. In conclusion, cardiac disease and low baseline Alb values are possible risk factors for CIN.

Relationship of Prescribed Drugs with the Risk of Fall in Inpatients.

Falls are common in elderly patients and are often serious. Several drugs have been associated with an increased risk of fall. Older adults often take multiple drugs for chronic diseases, and thus may be at increased risk from drugs associated with fall. We investigated the association between drug use and falling in hospitalized older people, with the goal of identifying medications that may increase the risk of a fall. A retrospective case control study was performed at the National Hospital Organization Kumamoto Saishunso Hospital in Japan. Medications taken by patients who fell (n=57) were compared with those taken by patients who did not fall (n=63). The median age (interquartile range; IQR) of the fall and non-fall groups were 75.0 (67.0-83.0) and 80.0 (70.3-84.5) years, respectively. The characteristics of the two groups were similar, with no significant differences in age, sex, or body weight. The probability of falling increased when the patients used zolpidem [odds ratio (OR)=2.47; 95%CI: 1.09-5.63; p<0.05] and calcium channel antagonists (OR=0.299; 95%CI: 0.13-0.68; p<0.01), and was also related to physical factors (OR=2.27; 95%CI: 1.01-5.09; p<0.05). Elderly patients taking zolpidem may fall due to sleepiness, and blood pressure control may be important to prevent orthostatic high blood pressure. In the treatment of elderly people, medical staff should try to choose drugs that prevent fall or are not associated with falling.

Comparison of predictive accuracy of teicoplanin concentration using creatinine clearance and glomerular filtration rate estimated by serum creatinine or cystatin C.

We compared the predictive accuracy of TEIC concentrations (TEIC_conc) calculated using either serum cystatin C (CysC) or serum creatinine (SCr) and the population mean method using the mean population parameter of TEIC_conc for Japan. We also compared the predicted TEIC_conc to measured TEIC_conc. Creatinine clearance (CLCr) predicted using the Cockcroft-Gault (C&G) equation with SCr was 45.23 mL/min (interquartile range [IQR]: 32.12-58.28), and the glomerular filtration rate (GFR) predicted using the Hoek equation with CysC was 45.23 mL/min (IQR: 35.40-53.79). The root mean-squared prediction error (IQR) based on CLCr predicted using the C&G equation with SCr was 6.88 (3.80-9.96) µg/mL, and that based on GFR predicted using the Hoek equation with CysC was 6.72 (3.77-9.68) µg/mL. Predicted TEIC_conc did not differ significantly between the two methods. The predictive accuracy of the TEIC_conc using the Hoek equation with CysC was similar to that of CLCr using the C&G equation with SCr. These findings suggest that the predictive accuracy of the TEIC_conc using CLCr based on the G&G equation and SCr might be sufficient for the initial dose adjustment of TEIC. Given that we were unable to confirm that CysC is the optimal method for predicting TEIC_conc, the expensive measurement of CysC might not be necessary.

Elevations of urinary pH may lower vancomycin serum concentration.

OBJECTIVE: This study investigated endogenous factors that may increase the elimination of vancomycin (VCM) in adult methicillin-resistant Staphylococcus aureus (MRSA) patients with pneumonia. METHODS: 48 patients (32 men and 16 women) admitted to the National Hospital Organization Kumamoto Medical Center for pneumonia due to MRSA were evaluated. VCM (500 - 2,000 mg/dose) was administered intravenously for 60 - 120 min at 8- - 12-h intervals. The dose of VCM prescribed was determined based on the treatment guidelines of the Infectious Diseases Society of America and was dependent on a patient's creatinine clearance. RESULTS: Univariate analysis identified that potassium value (K) (p = 0.081) and urinary pH (p = 0.026) were possibly associated with decreased VCM concentration. Multivariate analysis confirmed that urinary pH was an independent risk factor for VCM clearance (p = 0.029). VCM clearance in patients with a urine pH of 8 was significantly higher (p = 0.032) than in patients with a urinary pH of 5. As urinary pH increased in alkalinity, a greater decrease in VCM concentrations was observed. CONCLUSIONS: Elevation of urinary pH promotes the urinary excretion of VCM, likely by promoting the dissociation of the carboxyl group of VCM. Thus, in the clinical setting, urinary pH should be measured and considered when determining dosage, as it may affect the VCM blood concentration.

Population Pharmacokinetic Approach to the Use of Low Dose Cyclosporine in Patients with Connective Tissue Diseases.

This study describes the population pharmacokinetics and dose personalization of cyclosporine in 36 patients with connective tissue diseases. A one-compartment open model with absorption was adopted as a pharmacokinetic model, and a nonlinear mixed effects model was used to analyze the population pharmacokinetic models. In the final model, age (AGE) and total body weight (TBW) were influential covariates on clearance (CL/F), which was expressed as CL/F (L/h)=17.8×(AGE/60)(-0.269)×(TBW/46.9)(0.408), in addition to the volume of distribution (Vd/F), (L)=98.0 and absorption rate constant (Ka) (h(-1))=0.67 (fixed). The results of the present study provide novel insights into factors involved in determining the most suitable dose and dosing strategy for individual patients with connective tissue disease.