Comparison of Analgesic Efficacy and Safety of Low-Dose Transdermal Fentanyl and Oral Oxycodone in Opioid-Naïve Patients with Cancer Pain.

In Japan, a low-dose transdermal fentanyl (TDF; 0.5 mg) has been approved to address pain in opioid-naïve patients with cancer; however, efficacy and safety data are lacking. To determine the efficacy and safety of TDF, patients with opioid-naïve cancer pain prescribed TDF (0.5 mg/d) and oral oxycodone sustained-release formulation (OXY) 10 mg/d were extracted from electronic medical and nursing records. Overall, 40 and 101 subjects were analyzed in the TDF and OXY groups, respectively. Compared with baseline (median [minimum, maximum]) values, changes in the Numerical Rating Scale (NRS) score on days 1, 3, and 7 post-administration were as follows: TDF (0 [-5, 4]) and OXY (-1.0 [-8, 3]); TDF (-1.5 [-6, 3]) and OXY (-2.0 [-8, 4]); and TDF (-2.0[-6, 3]) and OXY (-3.0[-8, 5]), respectively. No significant difference was observed between the groups on days 1 and 3; however, the change in the NRS on day 7 was significantly higher in the OXY group than that in the TDF group. Regarding adverse events, nausea occurred in 12.5 and 13.9% of patients in the TDF and OXY groups, respectively, while 12.5% of TDF- and 10.9% of OXY-treated patients experienced somnolence, revealing similar occurrence in both groups. However, constipation was more common in the OXY group (TDF: 50.0%, OXY: 71.3%). No serious adverse events (e.g., respiratory depression) were observed in either group. Low-dose TDF (0.5 mg), available only in Japan, showed comparable efficacy and safety to OXY (10 mg/d) and can be a first choice for opioid-naïve patients with cancer pain.

Disseminated Mycobacterium abscessus subsp. massiliense infection in a Good's syndrome patient negative for human immunodeficiency virus and anti-interferon-γ autoantibody: a case report.

BACKGROUND: Good's syndrome (GS) is characterized by immunodeficiency, and can lead to severe infection, which is the most significant complication. Although Mycobacterium rarely causes infection in patients with GS, disseminated nontuberculous mycobacterial (NTM) infection frequently occurs in GS patients that are also positive for the human immunodeficiency virus (HIV) or anti-interferon (IFN)-γ autoantibodies. Here, we report a rare case of GS with NTM without HIV or IFN-γ autoantibodies. CASE PRESENTATION: A 57-year-old Japanese male with GS and myasthenia gravis (treated with prednisolone and tacrolimus) was diagnosed with disseminated NTM infection caused by Mycobacterium abscessus subsp. massiliense. He presented with fever and back pain. Blood, lumbar tissue, urine, stool, and sputum cultures tested positive for M. abscessus. Bacteremia, spondylitis, intestinal lumber abscess, and lung infection were confirmed by bacteriological examination and diagnostic imaging; urinary and intestinal tract infections were suspected by bacteriological examination but not confirmed by imaging. Despite multidrug combination therapy, including azithromycin, imipenem/cilastatin, levofloxacin, minocycline, linezolid, and sitafloxacin, the patient ultimately died of the infection. The patient tested negative for HIV and anti-IFN-γ autoantibodies. CONCLUSIONS: Since myasthenia gravis symptoms interfere with therapy, patients with GS and their physicians should carefully consider the antibacterial treatment options against disseminated NTM.

Paradoxical Brain Embolism Caused by Isolated Pulmonary Arteriovenous Fistula Successfully Treated with Recombinant Tissue Plasminogen Activator.

Pulmonary arteriovenous fistula (PAVF), a vessel malformation connecting the pulmonary circulation to the systemic circulation while bypassing the pulmonary capillaries, can cause paradoxical cerebral infarction. It is often associated with hereditary hemorrhagic telangiectasia (HHT), a genetic disease characterized by multiple dermal, mucosal, and visceral telangiectasia causing recurrent bleeding. Paradoxical cerebral embolism caused by PAVF without HHT is rare. Here, we report a patient with isolated PAVF who experienced an ischemic stroke caused by a paradoxical embolism from deep venous thrombosis; the patient was successfully treated with recombinant tissue plasminogen activator. She presented with a decrease in arterial oxygen saturation to 91%, and lung disease was suspected. A PAVF was subsequently found in the right S6 region using contrast computed tomography. Interventional radiologists successfully occluded the shunt using 6 microcoils. PAVF should be considered when determining the pathogenesis of cerebral ischemia in patients with hypoxia, which can be the only symptom of PAVF.

Pharmacophore Modeling and Molecular Docking Studies of potential inhibitors to E6 PBM-PDZ from Human Papilloma Virus (HPV).

High-risk human papillomaviruses (HPVs) are known to cause cervical cancer. Vaccines are now available to prevent HPV infection. However, a clinically approved drug is yet not available to treat HPV. The PDZ(PSD-95/Dlg/ZO-1)-binding motif (PBM) in the E6 protein of HPVs targets the PDZ domain (known to be associated with oncogenesis) for degradation. Therefore, it is of interest to study PBM-PDZ interaction towards its possible inhibition with a potential inhibitor. Thus, four pharmocophore models of PBM-PDZ complex were developed. In order to obtain potent small molecules for its inhibition, a commercial compound database was screened using both these pharmacophore models and molecule docking method. These efforts identified four potential compounds (1-4) towards its inhibition with the docking scores range -18.2 to -15.0.

Meta-analysis of the risk of upper gastrointestinal hemorrhage with combination therapy of selective serotonin reuptake inhibitors and non-steroidal anti-inflammatory drugs.

It is thought that both selective serotonin reuptake inhibitors (SSRIs) and non-steroidal anti-inflammatory drugs (NSAIDs) can cause the adverse reaction of upper gastrointestinal hemorrhage (UGIH). To evaluate differences in the probability of UGIH occurring when SSRIs, NSAIDs, or both combined are administered, the authors performed a systematic review of related articles and a meta-analysis of data in those articles, which were identified by searching the literature published between 1999 and 2012 using PubMed, Scirus, and Google Scholar. The odds ratios were calculated using the Mantel-Haenszel method. The integrated odds ratios for SSRIs only, NSAIDs only, and the combination were 1.73 (0.65-2.82), 2.55 (1.51-3.59), and 4.02 (2.89-5.15), respectively. Use of the combination resulted in an odds ratio 2.32 times higher than use of either alone. Since the combination of SSRIs and NSAIDs resulted in a significantly higher risk of UGIH than either type of drug alone, clinicians should avoid use of the combination as much as possible. If it is necessary to administer both kinds of drugs, the minimum dosage should be prescribed for the shortest time period possible, and patients, particularly elderly patients, should be closely monitored for development of UGIH and other complications.

Statistical evaluation of single-photon emission computed tomography image using smoothed bootstrap method.

Many of the neurodegenerative diseases associated with a decrease in regional cerebral blood flow (rCBF) are untreatable, and the appropriate therapeutic strategy is to slow the progression of the disease. Therefore, it is important that a definitive diagnosis is made as soon as possible when such diseases are suspected. Diagnostic imaging methods, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT), play an important role in such a definitive diagnosis. Since several problems arise when evaluating these images visually, a procedure to evaluate them objectively is necessary, and studies of image analyses using statistical evaluations have been suggested. However, the assumed data distribution in a statistical procedure may occasionally be inappropriate. Therefore, to evaluate the decrease of rCBF, it is important to use a statistical procedure without assumptions about the data distribution. In this study, we propose a new procedure that uses nonparametric or smoothed bootstrap methods to calculate a standardized distribution of the Z-score without assumptions about the data distribution. To test whether the judgment of the proposed procedure is equivalent to that of an evaluation based on the Z-score with a fixed threshold, the procedure was applied to a sample data set whose size was large enough to be appropriate for the assumption of the Z-score. As a result, the evaluations of the proposed procedure were equivalent to that of an evaluation based on the Z-score.

A Practical Estimation Method for Analyzing Adverse Drug Reactions Using Data Mining.

This study aimed to determine the potentially severe chemical properties of drugs that can cause adverse drug reactions (ADRs) such as erythema multiforme (EM), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN) by using a data mining method. The study data were extracted from the Adverse Event Reporting System database of the FDA. EM was considered a mild reaction, and SJS and TEN were considered severe reactions. In this study, a new concept termed the "risk of aggravation" (ROA) was defined as whether a certain drug is more likely to cause severe adverse reactions than mild ones. Partial least squares and logistic regression analysis were applied using binary response variable ROAs. These analyses correctly predicted 50 of the 72 drugs associated with SJS and/or TEN and 28 of the 38 drugs associated with EM using binary chemical descriptors that are the same as those using the metric chemical descriptors.

Discovery of novel low-molecular-weight HIV-1 inhibitors interacting with cyclophilin A using in silico screening and biological evaluations.

Cyclophilin A has attracted attention recently as a new target of anti-human immunodeficiency virus type 1 (HIV-1) drugs. However, so far no drug against HIV-1 infection exhibiting this mechanism of action has been approved. To identify new potent candidates for inhibitors, we performed in silico screening of a commercial database of more than 1,300 drug-like compounds by using receptor-based docking studies. The candidates selected from docking studies were subsequently tested using biological assays to assess anti-HIV activities. As a result, two compounds were identified as the most active. Specifically, both exhibited anti-HIV activity against viral replication at a low concentration and relatively low cytotoxicity at the effective concentration inhibiting viral growth by 50%. Further modification of these molecules may lead to the elucidation of potent inhibitors of HIV-1.

Effects of indole on drug resistance and virulence of Salmonella enterica serovar Typhimurium revealed by genome-wide analyses.

BACKGROUND: Many Gram-positive and Gram-negative bacteria produce large quantities of indole as an intercellular signal in microbial communities. Indole demonstrated to affect gene expression in Escherichia coli as an intra-species signaling molecule. In contrast to E. coli, Salmonella does not produce indole because it does not harbor tnaA, which encodes the enzyme responsible for tryptophan metabolism. Our previous study demonstrated that E. coli-conditioned medium and indole induce expression of the AcrAB multidrug efflux pump in Salmonella enterica serovar Typhimurium for inter-species communication; however, the global effect of indole on genes in Salmonella remains unknown. RESULTS: To understand the complete picture of genes regulated by indole, we performed DNA microarray analysis of genes in the S. enterica serovar Typhimurium strain ATCC 14028s affected by indole. Predicted Salmonella phenotypes affected by indole based on the microarray data were also examined in this study. Indole induced expression of genes related to efflux-mediated multidrug resistance, including ramA and acrAB, and repressed those related to host cell invasion encoded in the Salmonella pathogenicity island 1, and flagella production. Reduction of invasive activity and motility of Salmonella by indole was also observed phenotypically. CONCLUSION: Our results suggest that indole is an important signaling molecule for inter-species communication to control drug resistance and virulence of S. enterica.

Predictive factors for postherpetic neuralgia using ordered logistic regression analysis.

OBJECTIVES: To identify predictive factors for the occurrence of postherpetic neuralgia (PHN). METHODS: The participants were 73 herpes zoster patients who had been treated at the pain clinic of our hospital between January 2008 and June 2010. Variables present at the initial visit were extracted from the clinical records for regression analysis of factors related to the occurrence of PHN. The following scores for response were used: 0=no PHN after 3 months; 1=PHN present after 3 months but absent after 6 months; and 2=PHN present after 6 months. Multivariate ordered logistic regression analysis was performed to identify the predictive factors for PHN. RESULTS: Advanced age [odds ratio (OR)=2.740, confidence interval (CI)=1.110-6.761; P=0.0288] and deep pain (OR=4.244, CI=1.114-16.163; P=0.0341) at the initial visit to our outpatient pain clinic were found to be significant predictive factors for the occurrence of PHN. Diabetes mellitus (OR=3.075) and pain reduced by bathing (OR=3.389) also had high OR, although they were not significant. DISCUSSION: Our study indicates that advanced age and deep pain at the initial visit are significant predictors for PHN. Our results are considered likely to contribute to the establishment of evidence-based medicine in the optimal treatment of PHN.

Factors predicting requirement of high-dose transdermal fentanyl in opioid switching from oral morphine or oxycodone in patients with cancer pain.

OBJECTIVES: To identify predictive factors requiring high-dose transdermal fentanyl in opioid switching from oral morphine or oxycodone to transdermal fentanyl in patients with cancer pain. METHODS: The participants were 76 hospitalized terminal cancer patients who underwent opioid switching from oxycodone or morphine sustained-release tablet to transdermal fentanyl at our hospital between January 2009 and June 2010. The conversion dose was calculated as transdermal fentanyl (25 µg/h)/oral morphine (60 mg) or oxycodone (40 mg)=1. The response evaluated was the dose conversion ratio [transdermal fentanyl/oral morphine or oxycodone (conversion dose to fentanyl)]=Y and was taken to be 0 for Y≤1, 1 for 1

Statistical identification of predictors for peripheral neuropathy associated with administration of bortezomib, taxanes, oxaliplatin or vincristine using ordered logistic regression analysis.

Chemotherapy-induced peripheral neuropathy (CIPN) is a major drug-induced adverse reaction that becomes a dose-limiting toxicity. However, effective strategies for preventing or treating CIPN are lacking. Accordingly, this study aimed to statistically identify predictors for CIPN. Retrospective analysis was carried out for 190 patients who had been treated with bortezomib (n=28), taxanes (paclitaxel or docetaxel; n=58), oxaliplatin (n=52) or vincristine (n=52) at our hospital between April 2005 and December 2008. The severity of CIPN was assessed at the time of chemotherapy completion, graded as grade 0-5 in accordance with the National Cancer Institute Common Terminology Criteria for Adverse Events v3.0. Multivariate ordered logistic regression analysis was used to investigate predictors for CIPN. Predictors for CIPN in patients that were administered bortezomib were no co-administration of dexamethasone [odds ratio (OR), 0.455; confidence interval (CI), 0.208-0.955; P=0.0376] and sex (male) (OR, 3.035; CI, 1.356-6.793; P=0.0069). For taxanes (paclitaxel or docetaxel), the predictor for CIPN was a large number of chemotherapy cycles (OR, 2.379; CI, 1.035-5.466; P=0.0412). For oxaliplatin, the predictors for CIPN were a large number of chemotherapy cycles (OR, 3.089; CI, 1.598-5.972; P=0.0008) and no co-administration of non-steroidal anti-inflammatory drugs (OR, 0.393; CI, 0.197-0.785; P=0.0082). For vincristine, predictors for CIPN were a large number of chemotherapy cycles (OR, 6.015; CI, 1.880-19.248; P=0.0025) and co-administration of an analgesic adjuvant (OR, 3.907; CI, 1.383-11.031; P=0.0101). In conclusion, our study indicates that CIPN will be alleviated by the co-administration of dexamethasone with bortezomib and non-steroidal anti-inflammatory drugs with oxaliplatin.

Nonlinear classification of hERG channel inhibitory activity by unsupervised classification method.

The side effects that occur in the central nervous system and circulatory system due to medicines are expected to be prevented by research and development. However, many of the compounds in medicines have the possibility of causing arrhythmia, and methods developed to detect this problem at the early stage of drug development are not always successful. In the present study, we classified drug compounds according to their activity using only structural information. To classify compounds, we used a self-organizing map (SOM), which is a nonlinear unsupervised classification method. We first analyzed a small-scale dataset, and an excellent classification result was obtained. We then applied our method to a large-scale dataset containing numerous inert compounds and were again able to classify the compounds according to their activity. Both classifications showed some compound activity, although a few differences between the two SOM maps were seen.

Statistical examination to determine whether only 48-h value for serum concentration during high-dose methotrexate therapy is a predictor for clinical adverse events using ordered logistic regression analysis.

Sustained elevation of serum methotrexate (MTX) concentrations (>1.0 microM) for 48 h (48-h value) has been found to have predictive significance for the development of toxicity. However, we sometimes experience severe adverse events during high-dose (HD) MTX therapy even if serum MTX concentrations comply with recommended values. We performed a retrospective study to identify predictors for occurrence of adverse events and examined whether only the 48-h value is a statistically significant predictor for clinical adverse events during HD MTX therapy. The subjects were 32 hematological patients (n = 58 episodes) treated with MTX at Kyoto Prefectural University of Medicine between February 2003 and July 2007. Ordered logistic regression analysis was used to identify predictors for occurrence of adverse events. The predictive factors identified were: 24-h continuous infusion therapy (24-h C-IV) (long infusion time) [odds ratio (OR) = 2.890, confidence interval (CI) =1.493-5.594; P = 0.0016] for fatigue, higher dose [OR = 2.282, CI = 1.287-4.046; P = 0.0048] and combination chemotherapy [OR = 2.177, CI = 1.059-4.477; P = 0.0344] for stomatitis, and 24-h C-IV [OR = 2.573, CI = 1.101-6.016; P = 0.0291] for neutropenia. We found that only the 48-h value was not a predictor for clinical adverse events for HD MTX therapy. A major limitation of the present study was the small number of participants. However, our findings suggest that there is evidence that a long infusion time is a significant predictor for general fatigue and neutropenia, while a higher dose and combination chemotherapy are predictors for stomatitis.

Statistical validation of the relationships of cancer pain relief with various factors using ordered logistic regression analysis.

OBJECTIVE: To clarify the relationships of cancer pain with various factors that prevent pain control statistically. METHODS: The participants were 71 terminal cancer patients admitted to the Department of Hematology/Oncology or Department of Gastroenterology/Hepatology, University Hospital, Kyoto Prefectural University of Medicine in whose pain control a pharmacist was involved as part of her clinical duties from January 2004 to November 2006. The effectiveness of pain control was evaluated using a 5-point verbal rating scale (0=excellent, 1=good, 2=moderate, 3=poor, and 4=very poor) by interviewing the patients. As pain was rated using a graded scale and as many factors were involved in pain, analysis was performed using ordered logistic regression analysis. Moreover, prediction of an optimal model was performed by leave-one-out cross-validation to eliminate unnecessary variables. A program to perform leave-one-out cross-validation by ordered logistic regression analysis was prepared, independent variables used in the model were increased one by one, and calculation was performed in all combinations. Then, the optimal model was predicted by calculating the percent accuracy of predictions and Spearman rank correlation coefficient. RESULTS: Nausea [odds ratio (OR)=1.948, P=0.0232], sex (OR=2.322, P=0.0030), and bone metastasis (OR=2.367, P=0.0017) remained as variables significantly correlated with pain when the number of independent variables was 5, and sex (OR=2.167, P=0.006) and bone metastasis (OR=2.093, P=0.005) remained when the number of variables was 6. DISCUSSION: The statistical identification of factors preventing pain control is considered to contribute to the establishment of an evidence-based approach to cancer pain relief.

Ethnic difference in patients with type 2 diabetes mellitus in inter-East Asian populations: a systematic review and meta-analysis focusing on gene polymorphism.

BACKGROUND: We previously reported that the fasting serum insulin level was significantly lower in Japanese patients than in Korean and Chinese patients, and showed evidence that a difference in the dietary component would be one of the most influential factors for the ethnic difference. However, it is well known that type 2 diabetes mellitus (T2DM) results from the interaction between genetic predispositions and environmental risk factors. Therefore, we investigated ethnic differences by focusing on gene polymorphism, possibly related to T2DM in Japanese, Korean, and Chinese subjects. METHODS: Data sources included MEDLINE and EMBASE between January 2001 and October 2008. We conducted a search for articles containing minor allele frequency (MAF) in the gene polymorphisms of peroxisome proliferator-activated receptor-γ (PPARG), inward-rectifying potassium channel Kir6.2 (KCNJ11), Calpain 10 (CAPN10), and transcription factor 7-like 2 (TCF7L2). The pooled odds ratio was calculated by using a fixed-effects model with the Mantel-Haenszel method after confirming statistical evidence of homogeneity across the ethnicities using the Breslow-Day test. RESULTS: The Breslow-Day test revealed that there were no statistically significant differences between ethnicities in pooled odds ratios for the gene polymorphisms in PPARG (P = 0.828), KCNJ11 (P = 0.194), CAPN10 (P = 0.090), and TCF7L2 (P = 0.376). Also, pooled odds ratios of each gene polymorphism in East Asians were 0.645 for PPARG (P = 0.000), 1.168 for KCNJ11 (P = 0.000), 0.967 for CAPN10 (P = 0.759), and 1.386 for TCF7L2 (P = 0.000). CONCLUSION: The results of this study and our previous studies suggest that behavioral and environmental risk factors have a more significant impact on ethnic difference in East Asian patients with T2DM compared with genetic predispositions.

Risk factors for infection in haematology patients treated with rituximab.

OBJECTIVES: Although rituximab therapy is not considered to be closely associated with infection, there have been reports of serious infections in patients treated with rituximab. We performed a statistical retrospective analysis to clarify the risk factors for infection in patients receiving rituximab therapy. METHODS: A retrospective study of data from clinical records was performed that targeted haematology patients treated at our university hospital between April 2003 and October 2006. We selected 63 patients with CD20-positive lymphoma whose peripheral blood immunoglobulin levels had been measured within 6 months before and after rituximab therapy. Logistic regression analysis was used to investigate the risk factors for serious infection in these patients. RESULTS: The three risk factors identified were: 1) reduction in IgM after administration of rituximab [odds ratio (OR) = 1.032, confidence interval (CI) = 1.007-1.057; P = 0.009], 2) duration of rituximab therapy [OR = 0.962, CI = 0.932-0.994; P = 0.021] and 3) G-CSF administration [OR = 4.825, CI = 1.411-16.495; P = 0.012]. CONCLUSIONS: Rituximab therapy may be associated with infection, indicating the need for sequential monitoring of IgM levels and identification of the optimal interval between rituximab cycles.

Ethnic difference in inter-East Asian subjects with normal glucose tolerance and impaired glucose regulation: a systematic review and meta-analysis focusing on fasting serum insulin.

AIMS: To investigate ethnic difference by focusing on fasting serum insulin (FSI) in inter-East Asian subjects with normal glucose tolerance (NGT) and impaired glucose regulation (IGR). METHODS: Data sources included MEDLINE and EMBASE between 2001 and 2007. We conducted a search for articles containing mean or geometric mean values of FSI in East Asian subjects with NGT, IGR, or type 2 diabetes (T2DM). The Monte Carlo method was used for simulation of the mean and standard deviation of individual measures in each ethnic group; calculation of the median ratio and 95% confidence interval of individual measures between ethnic groups. RESULTS: Twenty-two articles fully met our pre-determined criteria and were included in the meta-analysis. Results of the meta-analysis revealed that FSI level is significantly lower in Japanese subjects with NGT, IGR, or T2DM than in Korean and Chinese subjects. CONCLUSIONS: Ethnic difference in FSI level between East Asians was observed in not only T2DM patients but also subjects with NGT or IGR. The lower FSI level in Japanese subjects was accompanied by lower triglyceride level. These results suggest that ethnic difference in dietary habit was one of the most influential factors for the ethnic difference in FSI.

Ethnic difference in patients with type 2 diabetes mellitus in inter-East Asian populations: a systematic review and meta-analysis focusing on fasting serum insulin.

AIMS: To investigate ethnic difference by focusing on fasting serum insulin (FSI) in inter-East Asian patients with type 2 diabetes. METHODS: Data sources included MEDLINE and EMBASE between 2001 and 2006. We conducted a search for articles containing mean or geometric mean values of FSI in East Asian patients with type 2 diabetes. The Monte Carlo method was used for simulation of the mean and standard deviation of individual measures in each ethnic group; calculation of the median ratio and 95% confidence interval of individual measures between ethnic groups. RESULTS: The initial search identified a total of 996 journal articles. After reviewing the titles and abstracts of these articles, 201 studies were selected for further screening and the complete papers on these studies were then reviewed in detail. Of these, seven articles fully met our pre-determined criteria and were included in the meta-analysis. Results of the meta-analysis revealed that FSI level is significantly lower in Japanese patients than in Korean and Chinese patients. CONCLUSIONS: Results from our review of ethnic differences in dietary habit in the inter-East Asian population suggested that difference in dietary component was one of the most influential factors for the ethnic difference.

Population pharmacokinetics of itraconazole solution used as prophylaxis for febrile neutropenia.

Although administration of antifungal agents, such as itraconazole (ITC) solution, for prophylaxis is the most promising strategy for the treatment of haematological malignancies, little is known about the population pharmacokinetic (PK) parameters. A clinical study was conducted to identify PK parameters for the administration of 200mg/day ITC solution used as prophylaxis for febrile neutropenia in patients undergoing treatment. The study population comprised six patients. NONMEM software was used to estimate PK parameters. Clearance, volume of distribution and the absorption rate constant were 12.7 L/h, 333 L and 1.72 h(-1), respectively. These parameters were different from a previous study to large extent, which may be due to differences in intended patients. These differences strongly suggest that establishment of population pharmacokinetics is essential for planning a prospective clinical trial. Assuming a normal distribution, we predicted the trough concentrations of 94.5% of the patients receiving 200 mg/day ITC solution to be >250 ng/mL, indicating that administration of 200mg/day might be suitable for prophylaxis. This pilot study presents a basic PK model of ITC solution in Japanese haematological patients for the establishment of optimal administration. Large-scale studies will be necessary in the future to determine population PK parameters with covariates.