BMC Clinical Pharmacology最新文献

Background: Roflumilast is an oral, selective phosphodiesterase 4 inhibitor with anti-inflammatory effects in chronic obstructive pulmonary disease (COPD). The addition of roflumilast to long-acting bronchodilators improves lung function in patients with moderate-to-severe COPD. The present study investigated drug-drug interaction effects between inhaled formoterol and oral roflumilast.

Methods: This was a single-centre (investigational clinic), open, randomised, multiple-dose, parallel-group study. In Regimen A, healthy men were treated with roflumilast (500 μg tablet once daily; Day 2-18) and concomitant formoterol (24 μg twice daily; Day 12-18). In Regimen B, healthy men were treated with formoterol (24 μg twice daily; Day 2-18) and concomitant roflumilast (500 μg once daily; Day 9-18). Steady-state plasma pharmacokinetics of roflumilast, roflumilast N-oxide and/or formoterol (Cmax and AUC0-τ) as well as pharmacodynamics - blood pressure, transthoracic impedance cardiography (ZCG), 12-lead digital electrocardiography, peripheral blood eosinophils, and serum glucose and potassium concentrations - were evaluated through Day 1 (baseline), Day 8 (Regimen B: formoterol alone) or Day 11 (Regimen A: roflumilast alone), and Day 18 (Regimen A and B: roflumilast plus formoterol). Blood and urine samples were taken for safety assessment at screening, pharmacokinetic profiling days and Day 19. Adverse events were monitored throughout the study.

Results: Of the 27 subjects enrolled, 24 were evaluable (12 in each regimen). No relevant pharmacokinetic interactions occurred. Neither roflumilast nor formoterol were associated with significant changes in cardiovascular parameters as measured by ZCG, and these parameters were not affected during concomitant administration. Formoterol was associated with a slight increase in heart rate and a corresponding shortening of the QT interval, without changes in the heart rate-corrected QTc interval. There were small effects on the other pharmacodynamic assessments when roflumilast and formoterol were administered individually, but no interactions or safety concerns were seen after concomitant administration. No severe or serious adverse events were reported, and no adverse events led to premature study discontinuation.

Conclusions: No clinically relevant pharmacokinetic or pharmacodynamic interactions were found when oral roflumilast was administered concomitantly with inhaled formoterol, including no effect on cardiac repolarisation. Roflumilast was well tolerated.

Background: In the last decades, the provision of pharmaceutical care by community pharmacists has developed in OECD countries. These developments involved significant changes in professional practices and organization of primary care. In France, they have recently been encouraged by a new legal framework and favored by an increasing demand for health care (increase in the number of patients with chronic diseases) and reductions in services being offered (reduction in the number of general practitioners and huge regional disparities).

Objectives: This study aimed to investigate final-year pharmacy students' opinions on 1/expanding the scope of pharmacists' practices and 2/the potential barriers for the implementation of pharmaceutical care. We discussed these in the light of the experiences of pharmacists in Quebec, and other countries in Europe (United Kingdom and the Netherlands).

Methods: All final-year students in pharmaceutical studies, preparing to become community pharmacists, at the University Paris-Descartes in Paris during 2010 (n = 146) were recruited. All of them were interviewed by means of a questionnaire describing nine "professional" practices by pharmacists, arranged in four dimensions: (1) screening and chronic disease management, (2) medication surveillance, (3) pharmacy-prescribed medication and (4) participation in health care networks. Respondents were asked (1) how positively they view the extension of their current practices, using a 5 point Likert scale and (2) their perception of potential professional, technical, organizational and/or financial obstacles to developing these practices.

Results: 143 (97.9%) students completed the questionnaire. Most of practices studied received a greater than 80% approval rating, although only a third of respondents were in favor of the sales of over-the-counter (OTC) drugs. The most significant perceived barriers were working time, remuneration and organizational problems, specifically the need to create a physical location for consultations to respect patients' privacy within a pharmacy.

Conclusions: Despite remaining barriers to cross, this study showed that future French pharmacists were keen to develop their role in patient care, beyond the traditional role of dispensing. However, the willingness of doctors and patients to consent should be investigated and also rigorous studies to support or refute the positive impact of pharmaceutical care on the quality of care should be carried out.

Background: Thiazolidinediones (TZDs), rosiglitazone (RGZ) and pioglitazone (PGZ) are widely used as hypoglycemic drugs in patients with type 2 diabetes mellitus. The aim of our study was to investigate the profile of adverse drug reactions (ADRs) related to TZDs and to investigate potential risk factors of these ADRs.

Methods: Type 2 diabetic patients were identified from the French Database of PharmacoVigilance (FPVD) between 2002 and 2006. We investigated ADR related to TZD, focusing on 4 ADR: edema, heart failure, myocardial infarction and hepatitis corresponding to specific WHO-ART terms.

Results: Among a total of 99,284 adult patients in the FPVD, 2295 reports concerned type 2 diabetic patients (2.3% of the whole database), with 161 (7%) exposed to TZDs. The frequency of edema and cardiac failure was significantly higher with TZDs than in other patients (18% and 7.4% versus 0.8% and 0.1% respectively, p < 0.001) whereas the frequency of hepatitis was similar (5.9% versus 4%, NS). A multiple logistic regression model taking into account potential confounding factors (age, gender, drug exposure and co-morbidities) found that TZD exposure remained associated with heart failure and edema, but not with hepatitis or myocardial infarction.

Conclusions: Thiazolidinediones exposure is associated with an increased risk of edema and heart failure in patients with type 2 diabetes even when recommendations for use are respected. In contrast, the risk of hepatic reactions and myocardial infarction with this class of drugs seems to be similar to other hypoglycemic agents.

Background: Risk of morbidity and mortality in patients with severe heart failure (HF) is reduced by blockade of aldosterone receptors with spironolactone. However, benefits of spironolactone are potentially limited by treatment compliance and adverse events profile. The aim of this study was to estimate use of spironolactone by patients with HF, incidence of key adverse events, and patient compliance.

Methods: This study was performed using data from the Quebec provincial medical and drug plans (Régie de l'Assurance Maladie du Québec, RAMQ) for patients who had a diagnosis of HF. Relative incidence of gynecomastia and hyperkalemia was estimated for users and non-users of spironolactone. Treatment adherence was estimated for users of spironolactone and compared to adherence with angiotensin converting enzyme (ACE) inhibitors, beta-blockers (β-blockers), and angiotensin receptor blockers (ARBs).

Results: RAMQ data were obtained for a total of 82,018 patients with a diagnosis of HF. Of these patients, 59.9% used an ACE inhibitor, 59.5% used a beta-blocker, 28.4% used an ARB, and 15.1% (n = 12,344) used spironolactone. Despite underestimation due to limitation of the database, the documented incidence of hyperkalemia (3.3% versus 1.4%) and gynecomastia (1.8% versus 0.7%) was significantly higher in spironolactone users than non-users (p < 0.001). Treatment compliance was significantly lower with spironolactone compared to ACE inhibitors, β-blockers, and ARBs (45.6% versus 56.1%, 59.7%, and 57.0%, respectively; p < 0.001). Persistence to treatment over a one-year period was also lower with spironolactone compared to ACE inhibitors, β-blockers, and ARBs (50.7% versus 64.5%, 70.4%, and 66.3%, respectively; p < 0.001).

Conclusion: Use of spironolactone is associated with an incidence of adverse events, which may have an impact on treatment compliance.

Background: Zibotentan (ZD4054) is a specific endothelin A (ETA) receptor antagonist being investigated for the treatment of prostate cancer. As zibotentan is eliminated by renal and metabolic routes, clearance may be reduced in patients with hepatic or renal impairment, leading to greater drug exposure.

Methods: Open-label studies investigated the PK and tolerability of zibotentan in subjects with hepatic or renal impairment, compared with those with normal organ function. In the hepatic and renal studies, respectively, subjects were divided into categories using Child-Pugh classification or 24-hour urine creatinine clearance (mild, moderate, or severe impairment and normal function). Each subject received a single oral dose of zibotentan 10 mg and PK sampling was undertaken. Within the hepatic study, AUC and Cmax were expressed as the ratio of geometric means and 90% CI for each impairment group compared with the normal function group. The possibility that hepatic impairment had a clinically relevant effect on exposure was considered if the upper 90% CI for the ratio exceeded 2. In the renal study, AUC, Cmax and t1/2 were analyzed using linear regression fitting effects for creatinine clearance and age.

Results: In the hepatic and renal studies respectively, 32 subjects (eight per group) and 48 subjects received treatment (n = 18 normal, n = 12 mild, n = 9 moderate, n = 9 severe). Zibotentan Cmax was not significantly affected by hepatic or renal impairment. Compared with the normal function group, zibotentan AUC was 40% (1.40; 90% CI 0.91-2.17), 45% (1.45; 90% CI 0.94-2.24) and 190% (2.90; 90% CI 1.88-4.49) higher in subjects with mild, moderate and severe hepatic impairment, respectively, and 66% (1.66; 90% CI 1.38-1.99), 89% (1.89; 90% CI 1.50-2.39) and 117% (2.17; 90% CI 1.64-2.86) higher in subjects with mild, moderate and severe renal impairment, respectively. In both studies mean t1/2 increased and zibotentan clearance decreased with the degree of impairment. Headache was the most common AE in all groups.

Conclusions: Zibotentan absorption was unchanged, however, exposure was higher in subjects with hepatic or renal impairment due to slower clearance. This increased exposure did not result in differences in the range or severity of AEs observed.

Trial registration: ClinicalTrials.gov: NCT00672581 and AstraZeneca study number D4320C00016 (renal trial; conducted in Germany).

Background: Constipation and diarrhoea are common complaints and often reported as adverse drug reactions. This study aimed at finding associations between drugs and constipation and diarrhoea in a general population.

Methods: A selection of inhabitants in Oppland County, Norway participated in a cross-sectional survey. Information about demographics, diseases including gastrointestinal complaints classified according to the Rome II criteria and use of drugs were collected on questionnaires. Constipation was defined as functional constipation and constipation predominant Irritable Bowel Syndrome (IBS), and diarrhoea as functional diarrhoea and diarrhoea predominant IBS. Associations between drugs and constipation and diarrhoea were examined with multivariable logistic regression models. Based on the multivariable model, the changes in prevalence (risk difference) of the abdominal complaints for non-users and users of drugs were calculated.

Results: In total 11078 subjects were invited, 4622 completed the questionnaires, 640 (13.8%) had constipation and 407 (8.8%) had diarrhoea. To start using drugs increased the prevalence of constipation and diarrhoea with 2.5% and 2.3% respectively. Polypharmacy was an additional risk factor for diarrhoea. Use of furosemide, levothyroxine sodium and ibuprofen was associated with constipation, and lithium and carbamazepine with diarrhoea. The excess drug related prevalence varied from 5.3% for the association between ibuprofen and constipation to 27.5% for the association between lithium and diarrhoea.

Conclusions: Use of drugs was associated with constipation and diarrhoea in the general population. The associations are most likely adverse drug reactions and show that drug-induced symptoms need to be considered in subjects with these complaints.

Background: Phenoxodiol is a novel isoflavone currently being studied in clinical trials for the treatment of cancer. This study reports the pharmacokinetics of phenoxodiol in patients with cancer.

Methods: The pharmacokinetics of phenoxodiol was studied following a single intravenous (iv) bolus dose and during a continuous intravenous infusion. Three men with prostate cancer and 3 women with breast cancer received IV bolus phenoxodiol (5 mg/kg) and plasma was sampled for free and total phenoxodiol levels. On a separate occasion 5 of the same patients received a continuous intravenous infusion of phenoxodiol (2 mg/kg/h) and plasma was again sampled for free and total phenoxodiol levels. Phenoxodiol was measured using gradient HPLC with ultraviolet detection.

Results: Following bolus injection, free and total phenoxodiol appeared to follow first order pharmacokinetics. The elimination half-lives for free and total phenoxodiol were 0.67 ± 0.53 h and 3.19 ± 1.93 h, respectively, while the total plasma clearance rates were 2.48 ± 2.33 L/h and 0.15 ± 0.08 L/h, respectively. The respective apparent volumes of distribution were 1.55 ± 0.69 L/kg and 0.64 ± 0.51 L/kg. During continuous intravenous infusion, free phenoxodiol accumulated rapidly to reach a mean concentration at steady state of 0.79 ± 0.14 μg/ml after 0.87 ± 0.18 h. The apparent accumulation half-life of free phenoxodiol was 0.17 ± 0.04 h while the plasma clearance during continuous infusion was 1.29 ± 0.23 L/h.

Conclusions: Phenoxodiol has a short plasma half-life, particularly in the free form, leading to a rapid attainment of steady state levels during continuous intravenous infusion.

Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12610000334000.

Background: An increase in the use of drugs and polypharmacy have been displayed over time in spite of the fact that polypharmacy represents a well known risk factor as regards patients' health due to the adverse drug reactions, drug-drug interactions, and low adherence to drug therapy arising from polypharmacy. For policymakers, as well as for clinicians, it is important to follow the developing trends in drug use and polypharmacy over time. We wanted to study if the prevalence of polypharmacy in an entire national population has changed during a 4-year period.

Methods: By applying individual-based data on dispensed drugs, we have studied all dispensed prescribed drugs for the entire Swedish population during four 3-month periods 2005-2008. Five or more (DP ≥5) and ten or more (DP ≥10) dispensed drugs during the 3-month period was applied as the cut-offs indicating the existence of polypharmacy and excessive polypharmacy respectively.

Results: During the period 2005-2008, the prevalence of polypharmacy (DP≥5) increased by 8.2% (from 0.102 to 0.111), and the prevalence of excessive polypharmacy (DP≥10) increased by 15.7% (from 0.021 to 0.024).In terms of age groups, the prevalence of polypharmacy and excessive polypharmacy increased as regards all ages with the exception of the age group 0-9 years. However, the prevalence of excessive polypharmacy displayed a clear age trend, with the largest increase for the groups 70 years and above. Furthermore, the increase in the prevalence of polypharmacy was, generally, approximately twice as high for men as for women. Finally, the mean number of dispensed drugs per individual increased by 3.6% (from 3.3 to 3.4) during the study period.

Conclusions: The prevalence of polypharmacy and excessive polypharmacy, as well as the mean number of dispensed drugs per individual, increased year-by-year in Sweden 2005-2008.

Background: Mandatory generic substitution (GS) was introduced in Finland on 1 April 2003. The aim of this study was to explore and compare the impacts of GS on the activities of pharmaceutical companies representing mainly original or generic pharmaceutical products in Finland. The self-reported impact of GS from pharmaceutical companies' perspective was explored with a focus on the number of employees, the range of sales packages on the market, the marketing activities, the research and development of new pharmaceutical products and storage of pharmaceuticals.

Methods: A cross-sectional postal survey was conducted among pharmaceutical companies with an office in Finland and substitutable medicines in the Finnish pharmaceutical market one year (2004) and five years (2008) after the introduction of GS. Completed questionnaires were returned by 16 original and 7 generic product companies in 2004 (response rate 56%, n = 41) and by 16 original and 6 generic product companies in 2008 (response rate 56%, n = 39). Descriptive statistical analyses were performed.

Results: The number of employees (2004: n = 6/16, 2008: n = 7/16) and the amount of prescription medicine marketing (2004: n = 7/16, 2008: n = 8/16) decreased in many of the original product companies after the introduction of GS. GS resulted in problems related to the storage of pharmaceuticals in the original product companies shortly after GS was introduced (p = 0.032 between 2004 and 2008). In the generic product companies, the prescription medicine representatives' visits to pharmacies increased at the beginning of GS (p = 0.021 between 2004 and 2008). In addition, GS caused problems with the storage of pharmaceuticals one year and five years after the reform (2004: n = 4/7, 2008: n = 3/6). The differences between original and generic product companies regarding the impacts of GS were not, however, statistically significant. GS did not affect on the range of sales packages on the market or the research activities of the majority of companies.

Conclusions: The study suggests that GS has had impacts on the activities of pharmaceutical companies in Finland. There were also some differences, although not statistically significant, between the surveyed original and generic product companies regarding the self-reported impacts of GS. More investigations are needed in this field.

Background: Somatropin is recombinant human growth hormone (GH) used for the treatment of growth failure in children and GH deficiency in adults. Two concentrations of a liquid formulation have been developed: 5.83 and 8.0 mg/mL. This trial compared the pharmacokinetics (PK), safety and tolerability of these two liquid concentrations against the freeze-dried (FD) formulation in healthy volunteers.

Methods: In an open-label, single-centre, three-way crossover study, volunteers (aged 18-45 years) were given subcutaneous injections of the reconstituted FD and two liquid formulations in random sequential order, each at 4 mg/dose, with a 1-week wash-out period between doses. To suppress endogenous GH secretion, intravenous somatostatin was infused continuously 1 hour before to 24 hours after each dose, achieving a cumulative dose of 3 mg. Primary PK endpoints were area under the serum concentration-time curve (AUC0-t) and maximum serum concentration (Cmax). For each of the two liquid formulations, bioequivalence with the FD formulation was concluded if the 95% confidence intervals (CIs) for the estimated test/reference ratios of geometric means of AUC0-t and Cmax were within the standard pre-specified acceptance range (0.80-1.25).

Results: Fifteen men and 15 women enrolled (safety population, n = 30; PK population, n = 28). Bioequivalence with the FD formulation could be shown for both liquid formulations. The ratios of geometric means (95% CI) were 1.046 (0.980, 1.117) and 0.991 (0.929, 1.058) for AUC0-t and 0.954 (0.875, 1.040) and 0.955 (0.876, 1.041) for Cmax for the 5.83 and 8.0 mg/mL formulations, respectively. No significant differences between the three treatments in half-lives, time to reach Cmax, clearance or volume of distribution were observed. After injection, the most common side-effects were pain or injection-site reactions (all of mild intensity). There were no clinically significant abnormal vital signs, ECG or laboratory findings. There were 56 treatment-related adverse events (AEs): 49 mild, 6 moderate and 1 severe (vomiting). No serious AEs occurred. The pattern of AEs was as expected and all resolved by study end.

Conclusion: Both concentrations of a new liquid multi-dose formulation are bioequivalent to the FD reference formulation and all are well tolerated.

Trial registration number: NCT01034735.