Prescriptive Appropriateness: Inhospital Adherence to Proton Pump Inhibitors Deprescription Flow Chart.

The prescriptive appropriateness of Proton Pump Inhibitors (PPIs) in polypharmacy is controversial. PPIs are often overprescribed and the risk of prescribing errors and adverse drug reactions increases for each additional drug added to therapy. Hence, guided deprescription should be considered and easily implementable in ward practice. This observational prospective study evaluated the implementation of a validated PPIs deprescription flow chart to real-life internal ward activity through the presence of a clinical pharmacologist as an enhancing additional factor by assessment of inhospital prescriber's adherence to the proposed flow chart. Patients' demographics and prescribing trends of PPIs prescriptions were analyzed by descriptive statistics. The final analysis of data included ninety-eight patients (forty-nine male and forty-nine female), aging 75.6 ± 10.6 years; 55.1% of patients had home-PPIs prescriptions, while 44.9% received inhospital-PPIs prescriptions. Evaluation of prescriber's adherence to the flow chart revealed that the percentage of patients with a prescriptive/deprescriptive pathway conforming to that of the flow chart was 70.4%, with low symptomatologic recurrences. The clinical pharmacologists' presence and influence in ward activity may have contributed to this finding, since continuous training of the prescribing physicians is deemed a success-related factor in the deprescribing strategy. Multidisciplinary management of PPIs deprescription protocols shows high adherence by prescribers in real-life hospital settings and low recurrence events.

Pharmacokinetics and pharmacodynamics of antibiotics in cystic fibrosis: a narrative review.

Cystic fibrosis affects several organs, predisposing patients to severe bacterial respiratory infections, including those caused by methicillin-resistant Staphylococcus aureus. Cystic fibrosis is also associated with a wide spectrum of pathological changes that can significantly affect the absorption, distribution, metabolism, and/or elimination of several drugs, including antibacterial agents. Therefore, awareness of the pharmacokinetic derangements in patients with cystic fibrosis is mandatory for the optimisation of antibiotic therapy. This review discusses the basic principles of pharmacokinetics and the pathophysiology of the pharmacokinetics changes associated with cystic fibrosis; it also provides an update of available data for the most widely used antibiotics. Evidence accumulated in the last few years has clearly shown that a significant number of cystic fibrosis patients treated with conventional dosing schemes have sub-therapeutic antibiotic concentrations, increasing their risk of therapeutic failure and/or the emergence of resistant pathogens. Some proposals to optimise antibiotic therapies in this clinical setting based on therapeutic drug monitoring are also discussed.

Active pharmacovigilance program in patients affected by psoriasis and inflammatory bowel diseases
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OBJECTIVE: To help identify adverse events (AEs) in new biologic therapies and to spread the culture of pharmaceutical surveillance among patients affected by psoriasis or inflammatory bowel disease (IBD). MATERIALS AND METHODS: This active pharmacovigilance program provided all patients with telephone follow-ups (FU), carried out by a clinical pharmacologist for a total duration of 1 year. Collected AEs were classified according to the MedDRA dictionary. RESULTS: 21 patients with psoriasis and 10 patients with IBD were enrolled. In our sample, the AEs reported were frequent but mild, underlining the crucial role of active pharmacovigilance in detecting minor AEs rarely spontaneously reported by the patients. CONCLUSION: According to our experience, a multidisciplinary team is recommended to manage complex therapies improving AE reporting and promoting greater therapeutic adherence.

Co-Occurring Psychiatric and Substance Use Disorders: Clinical Survey Among a Rural Cohort of Italian Patients.

PURPOSE: Dual diagnosis (DD) is the co-occurrence of both a mental illness and a substance use disorder (SUD). Lots of studies have analysed the integrated clinical approach, which involves both psychiatry and toxicology medical experts. The purpose of this study is to analyse the socio-demographic characteristics and treatment strategies of patients with DD in a rural area of Italy. PATIENTS AND METHODS: Clinical data of 750 patients were collected in 2016 through the analysis of health plan records. RESULTS: The rate of co-occurring disorders is highly variable among people with SUD. In the considered area, patients with DD are 24%, of these only 46.1% have been treated with an integrated clinical program. Moreover, this percentage is further reduced (35.8%) if only patients with heroin use disorder are considered. CONCLUSION: A comprehensive revision of DD treatment is needed, especially for people suffering from heroin use disorder and living in remote areas. Meticulous data analysis from other addiction health services of rural areas could be necessary to identify a science-based clinical intervention.

A UHPLC-MS/MS method for the quantification of Δ9-tetrahydrocannabinol and cannabidiol in decoctions and in plasma samples for therapeutic monitoring of medical cannabis.

Aim: Monitoring of blood levels of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) is necessary for optimization of administration of medical cannabis. We describe the validation of a ultra-HPLC-MS/MS method for quantifying THC and CBD from plasma and decoctions and its application for therapeutic drug monitoring.Materials & methods: Analyses were performed by using a TSQ Quantiva™ Triple Quadrupole coupled to a Ultimate 3000 UHPLC system with atmospheric pressure chemical ionization after sample preparation with a straightforward method with deuterated internal standards. Results: The method has been validated following EMA guidelines and is linear in plasma from 0.16 to 10 ng/ml for both THC and CBD and in decoctions from 4.7 to 600 ng/ml. Conclusion: Given the unpredictable pharmacokinetic behavior of THC and CBD in patients, monitoring of plasma concentrations is strongly recommended for patients under treatment with medical cannabis.

What is known about deferasirox chelation therapy in pediatric HSCT recipients: two case reports of metabolic acidosis.

To date, in pediatric field, various hematological malignancies are increasingly treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Iron overload and systemic siderosis often occur in this particular cohort of patients and are associated with poor prognosis. We describe herein the case of two allo-HSCT patients, on treatment with deferasirox; they showed histopathological elements compatible with venoocclusive disease or vanishing bile duct syndrome in ductopenic evolution before deferasirox started. The first patient developed drug-induced liver damage with metabolic acidosis and the second one a liver impairment with Fanconi syndrome. After withdrawing deferasirox treatment, both patients showed improvement. Measurements of drug plasma concentrations were performed by HPLC assay. The reduction and consequent disappearance of symptoms after the suspension of deferasirox substantiate its role in inducing hepatic damage, probably enabling the diagnosis of drug-induced liver damage. But the difficulties in diagnosing drug-related toxicity must be underlined, especially in compromised subjects. For these reasons, in patients requiring iron-chelating therapy, close and careful drug therapeutic monitoring is strongly recommended.

ß-2 Agonists as Misusing Drugs? Assessment of both Clenbuterol- and Salbutamol-related European Medicines Agency Pharmacovigilance Database Reports.

A recent years' increase in misusing levels of image- and performance- enhancing drugs (IPEDs) has been observed. Out of these drugs, beta-2 agonists have recently emerged for their potential of misuse, especially for slimming and bodybuilding purposes. To this perspective, clenbuterol ('the size zero pill') has been reported as being both popular and widely available from the illegal market. All clenbuterol and salbutamol misuse/abuse/dependence/withdrawal/overdose/off-label spontaneous reports (2006-2016) from the European Medicines Agency (EMA) EudraVigilance (EV) database were collected and analysed by age range, gender, concomitant therapies and source of information. From the EV database, 55 of a total number of 920 'suspect' misuse/abuse/dependence/withdrawal/overdose/off-label ADRs (e.g. 5.97%; corresponding to 25 of 138 individuals) and 1310 of 62,879 ADRs (e.g. 2.08%; corresponding to 474 of 6923 individuals) were, respectively, associated with clenbuterol (typically ingested in combination with a range of anabolic steroids) and salbutamol. Proportional reporting ratio (PRR) value for misuse/abuse ADRs was higher (PRR = 18.38) for clenbuterol in comparison with salbutamol. Clenbuterol misuse/abuse could be a cause for major concern, especially in vulnerable individuals.

Pharmacokinetics of high-dose extended-infusion meropenem during pulmonary exacerbation in adult cystic fibrosis patients: a case series.

This case series explored the pharmacokinetic/pharmacodynamic (PK/PD) characteristics of meropenem (MEM) in adult cystic fibrosis (CF) patients hospitalized for a pulmonary exacerbation. From January 2015 to June 2016, all adult patients with cystic fibrosis (CF) and chronic pulmonary infection due to meropenem (MEM)-susceptible/intermediate Pseudomonas aeruginosa who received at least 48 h of MEM as an extended 3-hour infusion for treating a pulmonary exacerbation were enrolled. MEM plasma concentrations were determined by high-performance liquid chromatography. Six adult CF patients with a median age of 47 years were included in the study. MEM showed a high Vd (mean 45.98 L, standard deviation [SD] ±34.45). A minimal PK/PD target of 40% T > minimum inhibitory concentration (MIC) with respect to the MEM MIC of P. aeruginosa strains isolated from sputum during exacerbation was achieved in 5/6 patients (83%). MEM failed to achieve this target only in one patient, whose strain showed the highest MEM MIC in our cohort (8 mg/L). In all patients, MEM was well tolerated, and no adverse events were reported. In conclusion, high-dose, extended-infusion MEM during pulmonary exacerbation showed a high Vd in six adult CF patients with high median age, and was well tolerated.

Safety and tolerability of deferasirox in pediatric hematopoietic stem cell transplant recipients: one facility's five years' experience of chelation treatment.

42 pediatric patients with iron overload, who underwent liver biopsy and DFX treatment after hematopoietic stem cell transplantation were included in the study group. The patients were divided into two groups diversified according to deferasirox trough plasma concentrations (DFX Ctrough) with cut-off equal to10 mcg/mL. The average dose of DFX was 25.9 mg/kg in the DFX Ctrough < 10 mcg/mL group versus 19.2 mg/kg in the DFX Ctrough > 10 mcg/mL group (p=0,0003). The mean duration of DFX treatment was 135.7 days in the DFX Ctrough < 10 mcg/mL group versus 41.8 days in the DFX Ctrough > 10 mcg/mL group (p<0.0001). The mean tissue iron concentration in the DFX Ctrough < 10 mcg/mL group was 261.9 µmol/g versus 133.4 µmol/g in the DFX Ctrough > 10 mcg/mL group (p < 0.0001). 21 patients (100%) in the DFX Ctrough > 10 mcg/mL group had ductopenia which was complete in 47.6% of them and severe in 52.4%. All patients with particularly high Ctrough (> 25 mcg/mL) were found to have total ductopenia. 90.5% of all deferasirox-related adverse events and 100% of major adverse events occurred in the DFX Ctrough > 10 mcg/mL group. In the DFX Ctrough < 10 mcg/mL group only one patient interrupted chelation therapy versus 16 (84.2%) patients in the DFX Ctrough > 10 mcg/mL group. We would recommend a close monitoring in pediatric hematopoietic transplant recipients subjected to deferasirox-based therapy because we have observed a high incidence of adverse events and discontinuation of chelation treatment.

Codeine Precipitating Serotonin Syndrome in a Patient in Therapy with Antidepressant and Triptan.

The serotonin syndrome is a serioius medical condition due due to an intensive stimulation of setonin receptors. It is a rare, but severe, consequence of interaction between serotomimetic agents. This is a report of a 70-year-old woman steadily in therapy with venlafaxine and rizatriptan for migraine and major depressive syndrome. She was admitted to neurology unit for decreased light reflex with miotic pupils, global hyperreflexia, tremor, anxiety, ataxia and incoordination. The patient was diagnosed as a probable case of serotonin syndrome due to a pharmacological interaction between venlafaxine and rizatriptan trigged by opioid intake. In this paper, the development of syntomatology, the clinical examination and the possible pharmacokinetics explanation were carefully discussed and analysed.

Report on the International Workshop on Drug Prevention and Treatment in Rural Settings Organized by United Nation Office on Drugs and Crime (UNODC) and World Health Organization (WHO).

Very little evidence has been reported in literature regarding the misuse of substances in rural areas. Despite the common perception of rural communities as a protective and risk-mitigating environment, the scientific literature demonstrated the existence of many risk factors in rural communities. The Drug Prevention and Health Branch (DHB) of the United Nations Office on Drugs and Crime (UNODC), and the World Health Organization (WHO), in June 2016, organized a meeting of experts in treatment and prevention of SUDs in rural settings. The content presented during the meeting and the related discussion have provided materials for the preparation of an outline document, which is the basis to create a technical tool on SUDs prevention and treatment in rural settings. The UNODC framework for interventions in rural settings is a technical tool aimed to assist policy makers and managers at the national level. This paper is a report on UNODC/WHO efforts to improve the clinical conditions of people affected by SUDs and living in rural areas. The purpose of this article is to draw attention on a severe clinical and social problem in a reality forgotten by everyone.

Bromfenac ophthalmic solution 0.09 %: human aqueous humor concentration detected by high-performance liquid chromatography.

The purpose of this study was to evaluate the aqueous humor concentrations of bromfenac ophthalmic solution 0.09 % in patients undergoing phacoemulsification. Patients requiring cataract extraction received one drop (50 µL) of bromfenac 0.09 % solution in the eye to be operated, before bedtime the day before surgery or the morning of the surgery. The last administration was recorded. At the time of paracentesis, an aqueous humor sample was collected with a 30-gauge needle attached to a TB syringe and was later analyzed by high-performance liquid chromatography for drug concentration. 188 treated volunteers and 48 control, untreated, subjects were included in the study. The mean aqueous concentration of bromfenac in the treated group was 37.60 ± 68.86 and 0 nM (nmol/L) in the control group (p < 0.0001). Correlation coefficient in bromfenac group between time elapsed from instillation and drug concentration was -0.16 (p not significant). Bromfenac showed properties of good penetration and stable concentration in aqueous humor up to about 12 h after instillation.

Meropenem for treating KPC-producing Klebsiella pneumoniae bloodstream infections: Should we get to the PK/PD root of the paradox?

The objective of this study was to assess the achievement of pharmacokinetic/pharmacodynamic (PK/PD) targets of meropenem (MEM) in critically-ill patients with bloodstream infections (BSI) due to Klebsiella pneumoniae-carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) with MEM minimum inhibitory concentrations (MICs) ≥16 mg/L. Nineteen critically-ill patients with KPC-Kp BSI were given combination therapy including MEM, tigecycline, plus colistin or gentamicin (according to susceptibility testing). MEM was administered as an extended 3-hour infusion of 2 g every 8 hours, or adjusted according to renal function. MEM plasma concentrations were determined by high-performance liquid chromatography. PK/PD targets for MEM were defined as T > 40% 1×MIC and T > 40% 4×MIC. Possible synergisms between MEM and coadministered agents were assessed by time-kill assays based on plasma levels for MEM and on fixed plasma concentrations for the other agents. In none of 19 patients MEM reached any PK/PD target. The actual MEM MICs were 256, 512, and 1024 mg/L in 1, 3, and 15 isolates, respectively. However, theoretically, the PK/PD target of T > 40% 1×MIC could have been achieved in 95%, 68%, 32% and 0% of the isolates for MIC equal to 8, 16, 32, and 64 mg/L, respectively. No synergisms were observed between MEM and coadministered agents. In conclusion, high-dose MEM failed to reach PK/PD targets in 19 patients with BSI due to KPC-Kp with very high MEM MICs. On a theoretical basis, our results suggest a possible usefulness of MEM against resistant blood isolates with MICs up to 32 mg/L.

Population pharmacokinetics and probability of target attainment of meropenem in critically ill patients.

PURPOSE: Patients admitted to intensive care unit (ICU) with Klebsiella pneumoniae infections are characterized by high mortality. The aims of the present study were to investigate the population pharmacokinetics parameters and to assess the probability of target attainment of meropenem in critically ill patients to provide information for more effective regimens. METHODS: Twenty-seven consecutive patients were included in the study. Meropenem was administered as 3-h intravenous (i.v.) infusions at doses of 1-2 g every 8 or 12 h. Meropenem plasma concentrations were measured by a high-performance liquid chromatography (HPLC) method, and a population pharmacokinetics analysis was performed using NONMEM software. Meropenem plasma disposition was simulated for extended (3 h; 5 h) or continuous i.v. infusions, and the following parameters were calculated: time during which free drug concentrations were above minimum inhibitory concentration (MIC) (fT > MIC), free minimum plasma concentrations above 4× MIC (fCmin > 4× MIC), probability of target attainment (PTA), and cumulative fraction of response (CFR). RESULTS: Gender and severity of sepsis affected meropenem clearance, whose typical population values ranged from 6.22 up to 12.04 L/h (mean ± standard deviation (SD) value, 9.38 ± 4.47 L/h). Mean C min value was 7.90 ± 7.91 mg/L, suggesting a high interindividual variability. The simulation confirmed that 88 and 97.5 % of patients achieved effective C min > 4× MIC values after 3- and 5-h i.v. infusions of meropenem 2 g × 3/day, respectively. On the contrary, the same total daily doses reached the target C min > 4× MIC values in 100 % of patients when administered as continuous i.v. infusions. CONCLUSIONS: Several factors may influence meropenem pharmacokinetics in ICU patients. Continuous i.v. infusions of meropenem seem to be more effective than standard regimens to achieve optimal therapeutic targets.

Determination of deferasirox plasma concentrations: do gender, physical and genetic differences affect chelation efficacy?

OBJECTIVES: Bioavailability of deferasirox (DFX) is significantly affected by the timing of administration relative to times and to composition of meals. Its elimination half-life is also highly variable - in some patients as a result of gene polymorphisms. Understanding whether deferasirox plasma levels are related to specific characteristics of patients could help physicians to devise a drug regimen tailored the individual patient. METHODS: We analyzed deferasirox plasma concentrations (CDFX ) in 80 patients with transfusion-dependent anemias, such as thalassemia, by a high performance liquid chromatography (HPLC) assay. We used a multivariate linear regression model to find significant associations between CDFX and clinical/demographical characteristics of patients. All patients were genotyped for UGT1A1. RESULTS: Fifty-six patients were female, 24 were male, the great majority (88%) affected by ß-thalassemia, and 15 were children and adolescents. No statistical correlation was detectable between CDFX and DFX dose (P = 0.6). Age, time from last drug intake to blood sampling, and ferritin levels in the 6 months before study initiation were significantly and inversely associated with CDFX in univariate analysis. In the multivariate analysis, the only two factors independently and inversely associated with CDFX levels were time from last drug intake to blood sampling and ferritin levels (P = 0.006). A significant inverse correlation (P = 0.03) was observed between CDFX and UGT1A1*28 gene polymorphism, but only in patients with levels of lean body mass (LBM) below the median (P for interaction = 0.05). CONCLUSIONS: The results could indicate that a higher plasma DFX concentration could be associated with greater chelation efficacy. As a correlation between dose and CDFX was not demonstrated, it seems useful to monitor the concentrations to optimize and determine the most appropriate dose for each patient. Interesting results emerged from the analysis of genetic and physical characteristics of patients: LBM was a borderline significant effect modifier of the relationship between UGT1A1 polymorphisms and CDFX . Individual patient-tailored dosing of DFX should help to improve iron chelation efficacy and to reduce dose-dependent drug toxicity.

Measurement of sorafenib plasma concentration by high-performance liquid chromatography in patients with advanced hepatocellular carcinoma: is it useful the application in clinical practice? A pilot study.

Pharmacokinetics and dose-finding studies on sorafenib were conducted on heterogeneous groups of patients with solid tumors. Portal hypertension, gut motility impairment and altered bile enterohepatic circulation may explain different sorafenib toxicological profile in cirrhotic patients. This study evaluated sorafenib plasma concentration in a homogeneous group of cirrhotic patients with hepatocellular carcinoma (HCC). Sorafenib concentrations were determined by liquid chromatography in 12 consecutive patients. Data have been evaluated by the generalized estimating equations method (p value statistical level was set at α = 0.05). (1) There were not significant differences between sorafenib concentrations in patients who tolerate the full dose versus patients with reduced dose due to toxicity; (2) the average sorafenib concentrations measured 3 h after the morning dosing were lower than those measured 12 h after the evening dosing (p = 0.005); (3) sorafenib concentrations decrease overtime (p < 10(-4)); (4) it has been found an association between the development of severe adverse reactions and sorafenib concentrations (p < 10(-5)). The relationship between dose and concentration of sorafenib in HCC patients is poor and not clinically predictable, confirming the variability both in the maximum tolerated dose and in plasma concentrations. Several factors may influence the pharmacokinetics in patients with liver disease. This may explain the inter-patient variability of concentrations and the lack of differences in concentration at different dosages. It could be interesting to extend the series of HCC patients to enhance information on the kinetics of the drug; furthermore, to establish a threshold of plasma sorafenib concentrations to predict severe adverse reactions would be clinically useful.

Implementation strategies of Systems Medicine in clinical research and home care for cardiovascular disease patients.

Insights from the "-omics" science have recently emphasized the need to implement an overall strategy in medical research. Here, the development of Systems Medicine has been indicated as a potential tool for clinical translation of basic research discoveries. Systems Medicine also gives the opportunity of improving different steps in medical practice, from diagnosis to healthcare management, including clinical research. The development of Systems Medicine is still hampered however by several challenges, the main one being the development of computational tools adequate to record, analyze and share a large amount of disparate data. In addition, available informatics tools appear not yet fully suitable for the challenge because they are not standardized, not universally available, or with ethical/legal concerns. Cardiovascular diseases (CVD) are a very promising area for translating Systems Medicine into clinical practice. By developing clinically applied technologies, the collection and analysis of data may improve CV risk stratification and prediction. Standardized models for data recording and analysis can also greatly broaden data exchange, thus promoting a uniform management of CVD patients also useful for clinical research. This advance however requires a great organizational effort by both physicians and health institutions, as well as the overcoming of ethical problems. This narrative review aims at providing an update on the state-of-art knowledge in the area of Systems Medicine as applied to CVD, focusing on current critical issues, providing a road map for its practical implementation.

Uncommon serum creatine phosphokinase and lactic dehydrogenase increase during diosmin therapy: two case reports.

INTRODUCTION: Short-term administration of diosmin is usually considered safe, with only minor side effects (stomach and abdominal pain, diarrhea, dermatological disorders, and headache) occasionally observed. Within a 4-year period, a general practitioner noticed 17 cases of mild, diosmin-induced side effects, two of which showed particular interest. CASES PRESENTATION: Case 1: A 55-year-old Caucasian woman presented with chronic leg venous insufficiency. She was prescribed diosmin 450 mg twice a day. After 5 days of therapy, she developed pain in the legs (myalgia), and diosmin therapy was suspended. She made a spontaneous attempt of drug rechallenge and her leg pain reappeared. Thus, she underwent blood analysis, which showed elevation of creatine phosphokinase levels. Creatine phosphokinase values normalized only after prolonged discontinuation of the therapy. Case 2: A 79-year-old Caucasian man, who was diagnosed with acute hemorrhoidal syndrome. After 21 days of continuous diosmin treatment, increased levels of serum lactic dehydrogenase were detected. In both cases a comprehensive analysis of all possible causes for enzyme elevation was made. CONCLUSIONS: A feasible hypothesis to explain these rare effects could be that exaggerated adrenergic activity occurred on microcirculation, leading to an excessive peripheral vasoconstriction and subsequent ischemic damage. An individual predisposition is strongly suggested. A concurrence of events was probably responsible for the elevation of nonspecific tissue necrosis markers. Physicians and patients must be aware of these rare, but possible, adverse drug reactions.

HPLC determination of malondialdehyde as biomarker for oxidative stress: application in patients with alcohol dependence.

BACKGROUND: Chronic and excess ethanol exposure causes an increase in generation of free radicals which attack the polyunsaturated fatty acids in membranes to create lipid peroxides such as malondialdehyde (MDA) which is widely used as an indirect biomarker of oxidative stress. METHODS: In this study a sensitive and reproducible high performance liquid chromatography (HPLC) method for measurement of MDA was applied in a group of alcohol dependent patients who underwent detoxification treatment. RESULTS: Compared to the control group, mean MDA concentrations at baseline were significantly higher in alcohol dependent patients (1.28 +/- 0.58 microM vs. 0.9 +/- 0.21 microM; p < 0.02). However, MDA levels remained almost unchanged after three weeks of detoxification treatment (1.28 +/- 0.58 microM vs. 1.38 +/- 0.61 microM; p > 0.05). Among alcoholic patients, the MDA plasma concentration in smokers was higher than in non smokers both at baseline and after three weeks. CONCLUSIONS: The failure to reduce the levels of MDA after 3 weeks of detoxification treatment suggests that patients with chronic alcohol dependence have difficulty in compensating for alcohol-induced excessive production of free radicals. Furthermore, the possibility of cigarette smoke affecting the MDA plasma concentration cannot be ruled out.

Systemic absorption and pharmacokinetics of single-dose early intravesical mitomycin C after transurethral resection of non-muscle-invasive bladder cancer.

OBJECTIVE: To study the systemic absorption and pharmacokinetics of a single dose of intravesical mitomycin C (MMC) given immediately after transurethral resection of bladder tumor (TURBT). METHODS: Fourteen patients with primary or recurrent non-muscle-invasive bladder cancer were eligible for a single early intravesical instillation of MMC (40 mg in 50 mL distilled water) administered immediately after TURBT. Blood samples were obtained at baseline and at 20, 40, 60 (time of voiding), 90, 120, and 150 minutes after instillation. Concentrations of the drug were determined by validated high-performance liquid chromatography assay. During TURBT, we counted the number of excursions of the resecting loop required to completely eradicate the tumor, including a portion of the underlying muscular wall. TURBTs were categorized as small and large, defined as requiring ≤6 or >6 full excursions of the resecting loop, respectively. RESULTS: Maximal MMC plasma concentrations were reached 40 minutes after instillation. At 150 minutes, only minimal drug plasma levels were detectable in 4 patients. The highest plasma peak was 49.25 ng/mL. In the first samples, at 20 minutes after instillation, the plasma concentration of MMC was significantly correlated with the extent of TURBT (P = .026). Four patients (28.6%) complained of G1 side effects, 3 after a large TURBT and 1 after a small TURBT, and 1 patient had G2 dysuria after a large TURBT. CONCLUSION: Low peak blood levels of MMC are observed after a single-dose intravesical instillation immediately after TURBT, with low systemic and local toxicity. The early absorption rate depends on TURBT extension.