Reiko Yano

Semisynthesis of salviandulin E analogues and their antitrypanosomal activity.

A series of analogues of salviandulin E, a rearranged neoclerodane diterpene originally isolated from Salvia leucantha (Lamiaceae), were prepared and their in vitro activity against Trypanosoma brucei brucei was evaluated with currently used therapeutic drugs as positive controls. One of the 19 compounds prepared and assayed in the present study, butanoyl 3,4-dihydrosalviandulin E analogue was found to be a possible candidate for an antitrypanosomal drug with fairly strong antitrypanosomal activity and lower cytotoxicity.

Physicochemical Properties of Causative Drugs Associated with RenalNephrotoxicity

Background: In this study, we examined the association between drug-induced renal nephrotoxicity and the physiochemical properties of the causative drugs we extracted from CARPIS in order to provide drug information about potential severe risks at the time of and after marketing approval. Methods: We designated the nephrotoxicity-associated drugs as the case drug group (126 drugs), and all other drugs were set as the control drug group (915 drugs). We compared the physicochemical properties of the group. We performed univariate logistic regression analysis on each investigation item, and then performed multivariate stepwise logistic regression analysis on the items which were p<0.2 using univariate logistic regression analysis. Results: Model 1, which uses a logP value, showed that the odds ratio of pKa at less than 7 was 2.46, and that at less than 7-8 was 2.01. The odds ratio of logP value at less than 0 was 1.67. MW at less than 300-400 was 0.57. Model 2, which uses a logD value, showed that logD at less than 0 was 2.23. The odds ratio of pKa at less than 7 was 2.34, and at less than 7-8 was 2.04. The odds ratio of MW at less than 300-400 was 0.56. Conclusion: The results clearly showed the risk of renal problems associated with water-soluble drugs. The information could be useful to consider potential risks of renal problems associated with water-soluble drugs at the time of drug approval and after marketing and to compensate for the lack of information.

Relationship between Physicochemical Properties of Medical Supplies and Serious Adverse Drug Reactions Listed in the Package Inserts.

We sought to clarify the relationship between the physicochemical properties of each medical supply and serious adverse drug reactions listed in the package inserts, by reviewing new information. We investigated 1) 1078 medicines currently available on the domestic Japanese market by using physicochemical data, such as cLogD, molecular weight (MW), and pKa and 2) the serious adverse drug reactions stated in the package inserts and the presence or absence of serious renal and liver disorders, as well as mental, extrapyramidal, and skin disorders. The renal disorders data showed: cLogD<0, adjusted odds ratio (aOR)=2.00; MW values ≥500, aOR=2.28; and pKa<7.4, aOR=1.95-2.06. The liver disorders data showed: pKa<8.4, aOR=1.83-1.95, and MW values ≥300, aOR=1.47-1.87. The mental disorders data showed: cLogD≥0, aOR=2.12, and MW values<400, aOR=2.46-2.85. The extrapyramidal disorders data showed: pKa≥6.4, aOR=4.50-11.32; cLogD≥0, aOR=4.71; and MW values<500, aOR=7.95-15.08. The skin disorders data showed: cLogD<0, aOR=1.46; MW values ≥500, aOR=1.69; and pKa<6.4, aOR=1.65 or<7.4-8.4, aOR=1.59. This information will be useful for investigating the relationships between new drugs entering the market and their potential future adverse drug reactions, and for establishing both precautionary and medical observational standards.

Exploring Risk Factors that Contribute to the Onset of Ritodrine-Associated Serious Adverse Drug Reactions

Background: Ritodrine is a drug used for threatened premature labor. The severe adverse drug reactions associated with ritodrine are known to be pneumonedema, leukopenia, and rhabdomyolysis, but there have been few investigations on the risk factors. We performed a case-control study and selected case reports as a case group and healthy pregnant women in clinical practice as a control group. Methods: We extracted the onsets of pneumonedema, leukopenia, and rhabdomyolysis associated with ritodrine from case reports in Japan as a case group. We selected healthy pregnant women with ritodrine administration in clinical practice as a control group. We investigated their age, medical history; Pregnancy Induced Hypertension (PIH), multiple pregnancies, concomitant drugs administered, and maximum rate of ritodrine infusion, and examined the association with those factors with the onset of adverse drug reactions by logistic regression analysis. Results: The results of the case group showed: pneumonedema (28 cases); leukopenia (25 cases); rhabdomyolysis (21 cases). The risk factors significantly associated with pneumonedema are a medical history of the cardiovascular system, PIH, multiple pregnancy, and concomitant treatment with steroids, which all match with the precautions in ritodrine’s package insert. The factors associated with leukopenia are its administration longer than 7 days and the concomitant treatment with Mg. The factors associated with rhabdomyolysis are multiple pregnancies and a concomitant treatment with Mg. Conclusion: Risk factors for the onset of pneumonedema match the descriptions in the ritodrine package insert, and can be explained by pharmacological actions. Thus, this study could elucidate the risk factors for rare adverse drug reactions limited to pregnant women. The onsets of leukopenia and rhabdomyolysis were caused by physiological changes by pregnancy and its progression of disease state and ritodrine’s pharmacological action, and were suggested the possibility of risk factors.