Rapid Reduction in Use of Antidiabetic Medication after Laparoscopic Sleeve Gastrectomy: The Newfoundland and Labrador Bariatric Surgery Cohort (BaSCo) Study

Background:

Patients who have undergone bariatric surgery generally need fewer medications as they experience improvement in, or even resolution of, various medical conditions, including type 2 diabetes mellitus, hypertension, and dyslipidemia. Published data on changes in medication use after laparoscopic sleeve gastrectomy, a type of bariatric surgery that is growing in popularity, are limited.

Objective:

To determine whether patients took fewer medications for management of type 2 diabetes, hypertension, and dyslipidemia after laparoscopic sleeve gastrectomy, relative to preprocedure medications.

Methods:

In this prospective, single-centre cohort study, a nurse practitioner used standard medication reconciliation and study data-extraction forms to interview adult patients who had undergone laparoscopic sleeve gastrectomy and determine their medication use and pertinent demographic data. The data were analyzed using generalized estimating equations and standard statistical software. Outcome measures included changes in the use of antidiabetic, antihypertensive, and antilipemic medications at 1, 3, and 6 months after the surgery.

Results:

A total of 65 patients who underwent laparoscopic sleeve gastrectomy between May 2011 and January 2014 met the study inclusion criteria. Before surgery, the 30 patients with type 2 diabetes were taking an average of 1.9 antidiabetic medications. One month after the procedure, 15 (50%) had discontinued all antidiabetic medications, with a further decline at 3 and 6 months (p < 0.001 at each time point). Among the patients who were taking antihypertensives (n = 48) and antilipemics (n = 33) before surgery, the decline in use occurred at a more modest rate, with 6 (12%) and 2 (6%), respectively, discontinuing these medication classes within 1 month, and 12 (25%) (p = 0.001) and 8 (24%) (p = 0.015) having discontinued by 6 months.

Conclusions:

These findings suggest that patients with a history of type 2 diabetes mellitus, hypertension, and/or dyslipidemia who undergo laparoscopic sleeve gastrectomy are less likely to require disease-specific medications shortly after surgery.     

Intake of St John's wort improves the glucose tolerance in healthy subjects who ingest metformin compared with metformin alone

Aims

Our objective was to investigate the steady-state pharmacokinetic and pharmacodynamic interaction between the antidepressive herbal medicine St John''s wort and the antidiabetic drug metformin.

Methods

We performed an open cross-over study in 20 healthy male subjects, who received 1 g of metformin twice daily for 1 week with and without 21 days of preceding and concomitant treatment with St John''s wort. The pharmacokinetics of metformin was determined, and a 2 h oral glucose tolerance test was performed.

Results

St John''s wort decreased the renal clearance of metformin but did not affect any other metformin pharmacokinetic parameter. The addition of St John''s wort decreased the area under the glucose concentration–time curve [702 (95% confidence interval, 643–761) vs. 629 min*mmol/L (95% confidence interval, 568–690), P = 0.003], and this effect was caused by a statistically significant increase in the acute insulin response.

Conclusions

St John''s wort improves glucose tolerance by enhancing insulin secretion independently of insulin sensitivity in healthy male subjects taking metformin.     

High dose benzodiazepines prolong reaction times in chronic users who have major depressive and/or anxiety disorders

Aim

Short term administration of benzodiazepines (BZD) was found to prolong reaction time (RT) in experimental studies. However, studies on long term BZD use did not always adjust for important confounders and showed inconsistent results. We aimed to identify a possible relationship between long term BZD use and RT in BZD users in this large cross-sectional, observational study.

Methods

The RTs of non-users (n = 2404) were compared with low (n = 288), intermediate (n = 74), and high dose BZD users (n = 57) in the Netherlands Study of Depression and Anxiety (NESDA). RTs were obtained from the Implicit Association Test. Analyses were adjusted for sociodemographic characteristics, health indicators, severity of psychopathology and antidepressant use.

Results

Of the NESDA participants, 419 subjects (14.8%) used BZDs. A higher dose of BZDs was associated with prolonged RTs (P = 0.01). When comparing the different dose groups, the high dose group, but not the low and medium dose groups, had significantly longer RTs than the non-users.

Conclusions

Tolerance for the RT prolonging effect of relatively high doses of BZDs does not seem to develop. As prolonged RTs can have adverse consequences in daily life, BZDs should be prescribed conservatively at the lowest possible dose.     

Incidence of fatal adverse drug reactions: a population based study

Aims

To determine the incidence of fatal adverse drug reactions (FADRs) in a Swedish population.

Methods

Every seventh randomly selected deceased in three counties in South-east Sweden during 1 January 2001–31 December 2001 was identified in the Cause of Death Register. Relevant case records (hospitals and/or primary care centres and medicolegal files) were reviewed to identify suspected drug-related fatalities.

Results

Of 1574 deceased study subjects, 49 (3.1%; 95% CI 2.2%, 4.0%) were suspected to have died from FADRs. The most common suspected FADRs were gastrointestinal haemorrhages (n = 18; 37%), central nervous system haemorrhages (n = 14; 29%), cardiovascular disorders (n = 5; 10%), other haemorrhages (n = 4; 8%) and renal dysfunction (n = 3; 6%). The drugs most commonly implicated in FADRs were antithrombotic drugs (n = 31; 63%), followed by nonsteroidal anti-inflammatory drugs (NSAIDs) (n = 9; 18%), antidepressants (n = 7; 14%) and cardiovascular drugs (n = 4; 8%). Of all the 639 fatalities in hospital 41 (6.4%; 95% CI 4.5%, 8.3%) were suspected to be due to FADRs.

Conclusions

The medical burden of FADRs is significant. Haemorrhages were seen in a majority of the FADRs; antithrombotic agents or NSAIDs were implicated in most of these events. These results suggest that preventive measures should be taken to reduce the number of deaths caused by drugs.

What is already known about this subject

• Although drugs generally are safe and effective therapies for numerous diseases, adverse drug reactions do occur and may even be fatal.
• The incidence of fatal adverse drug reactions in hospitalized patients has been estimated to be approximately 5%.
• In previous studies the incidence of fatal adverse drug reactions in hospitalized patients has been reported, but the incidence of fatal adverse drug reactions in the general population is largely unknown.

What this study adds

• Fatal adverse drug reactions account for approximately 3% of all deaths in the general population.
• Haemorrhages amount to almost two-thirds of the fatal adverse drug reactions and antithrombotic agents are implicated in more than half of the suspected fatal adverse drug reactions.
• Fatal adverse drug reactions are estimated to be the seventh most common cause of death in Sweden.

     

Developing consensus on hospital prescribing indicators of potential harms amenable to decision support

Aims

To develop a list of prescribing indicators specific for the hospital setting that would facilitate the prospective collection of high-severity and/or high-frequency prescribing errors, which are also amenable to electronic clinical decision support.

Methods

A two-stage consensus technique (electronic Delphi) was carried out with 20 experts across England. Participants were asked to score prescribing errors using a five-point Likert scale for their likelihood of occurrence and the severity of the most likely outcome. These were combined to produce risk scores, from which median scores were calculated for each indicator across the participants in the study. The degree of consensus between the participants was defined as the proportion that gave a risk score in the same category as the median. Indicators were included if a consensus of 80% or more was achieved.

Results

A total of 80 prescribing errors were identified by consensus as being high or extreme risk. The most common drug classes named within the indicators were antibiotics (n = 13), antidepressants (n = 8), nonsteroidal anti-inflammatory drugs (n = 6) and opioid analgesics (n = 6). The most frequent error type identified as high or extreme risk were those classified as clinical contraindications (n = 29 of 80).

Conclusions

Eighty high-risk prescribing errors in the hospital setting have been identified by an expert panel. These indicators can serve as a standardized, validated tool for the collection of prescribing data in both paper-based and electronic prescribing processes. This can assess the impact of safety improvement initiatives, such as the implementation of electronic clinical decision support.     

Red ginseng for treating erectile dysfunction: a systematic review

AIMS

Korean red ginseng (unskinned Panax ginseng before it is steamed or otherwise heated and subsequently dried) is one of the most widely used herbal remedies. This systematic review evaluates the current evidence for the effectiveness of red ginseng for treating erectile dysfunction.

METHODS

Systematic searches were conducted on 20 electronic databases without language restrictions. Hand-searches included conference proceedings and our files. All randomized clinical studies (RCT) of red ginseng as a treatment of erectile dysfunction were considered for inclusion. Methodological quality was assessed using the Jadad score.

RESULTS

Seven RCTs met all the inclusion criteria. Their methodological quality was low on average. Six of the included RCTs compared the therapeutic efficacy of red ginseng with placebo. The meta-analysis of these data showed a significant effect (n = 349, risk ratio, 2.40; 95% CI of 1.65, 3.51, p < 0.00001, heterogeneity: tau² = 0.05, χ² = 6.42, p = 0.27, I² = 22%). Subgroup analyses also showed beneficial effects of red ginseng in psychogenic erectile dysfunction (n = 135, risk ratio, 2.05; 95% CI of 1.33, 3.16, p = 0.001, heterogeneity: χ² = 0.08, p = 0.96, I² = 0%).

CONCLUSIONS

Collectively these RCTs provide suggestive evidence for the effectiveness of red ginseng in the treatment of erectile dysfunction. However, the total number of RCTs included in the analysis, the total sample size and the methodological quality of the primary studies were too low to draw definitive conclusions. Thus more rigorous studies are necessary.     

Reduction of dietary fat absorption by the novel gastrointestinal lipase inhibitor cetilistat in healthy volunteers

AIMS

To assess the efficacy, pharmacodynamics, safety and tolerability of a range of doses of cetilistat, a novel inhibitor of gastrointestinal lipases, in healthy volunteers.

METHODS

Three Phase I, randomized, placebo-controlled, parallel-group studies were conducted. Enrolled subjects in the three studies (n = 99) received a controlled calorie diet (total intake 2160 calories daily, 30% from fat). Twenty-four subjects were randomized to placebo and 66 were randomized to the following cetilistat doses: 50 mg three times daily [t.i.d. (n = 7)], 60 mg t.i.d. (n = 9), 100 mg t.i.d. (n = 7), 120 mg t.i.d. (n = 9), 150 mg t.i.d. (n = 16), 240 mg t.i.d. (n = 9) and 300 mg t.i.d. (n = 9). Nine subjects received the approved orlistat dose (120 mg t.i.d.). Treatment was for 5 days, with a 2-day run-in period and 1-day post-treatment follow-up. The primary outcome measure was daily faecal fat excretion. Secondary outcomes included plasma lipid levels, tolerability [gastrointestinal adverse events (AEs)] and safety.

RESULTS

Cetilistat increased faecal fat excretion relative to baseline at all doses. Cetilistat was well tolerated, with gastrointestinal AEs the most common (51%). Steatorrhoea (oily stool) was more frequent in the orlistat group (4.11 events per subject) than in any cetilistat dose group (0.14–1.81 events per subject). Most AEs (98%) were mild or moderate in intensity.

CONCLUSIONS

Cetilistat increased dietary fat excretion in healthy volunteers receiving a controlled calorie diet. Cetilistat was well tolerated at all doses examined and tolerability appeared to be improved relative to orlistat. Faecal fat excretion in the cetilistat groups was at least comparable to the orlistat 120 mg t.i.d. group.     

Influence of different degrees of liver impairment on the pharmacokinetics of clazosentan

AIM

To investigate the effect of mild, moderate and severe liver impairment on the pharmacokinetics (PK), tolerability and safety of clazosentan, an intravenous endothelin receptor antagonist.

METHODS

Healthy subjects with normal liver function (n = 8), subjects with mild (Child Pugh A, n = 8), and with moderate (Child-Pugh B, n = 8) liver impairment received a continuous intravenous infusion of 1 mg h⁻¹ and subjects with severe liver impairment (Child Pugh C, n = 8) received a continuous intravenous infusion of 0.5 mg h⁻¹ clazosentan for a duration of 6 h. The pharmacokinetic (PK) parameters of clazosentan were determined by both model-independent and model-dependent methods.

RESULTS

Mean plasma concentrations of clazosentan increased with increasing severity of liver impairment. Geometric means of area under the plasma concentration–time curve from 0 to infinity (AUC_(0,∞)) were 1.41- (90% CI 1.04, 1.90), 2.37- (90% CI 1.75, 3.19), and 3.79- (90% CI 2.81, 5.11) fold higher in subjects with mild, moderate and severe liver impairment, respectively, compared with healthy subjects. Similar results were obtained by non-compartmental and two-compartmental analysis. A significant positive correlation between clazosentan AUC_(0,∞) and Child-Pugh score (r = 0.83), bilirubin (r = 0.78) and prothrombin time (r = 0.62), and a significant negative correlation with albumin concentrationl (r = 0.71) was observed. Administration of clazosentan was well tolerated in all groups.

CONCLUSIONS

The increase in exposure to clazosentan in Child-Pugh A patients is not expected to be clinically relevant and no dose adjustment for these patients is proposed. It is recommended to reduce the dose of clazosentan to half in Child-Pugh B and to one fourth in Child-Pugh C patients.     

Does β-adrenoceptor blocker therapy improve cancer survival? Findings from a population-based retrospective cohort study

AIMS

To examine the effect of β-adrenoceptor blocker treatment on cancer survival.

METHODS

In a UK primary care database, we compared patients with a new cancer diagnosis receiving β-adrenoceptor blockers regularly (n = 1406) with patients receiving other antihypertensive medication (n = 2056).

RESULTS

Compared with cancer patients receiving other antihypertensive medication, patients receiving β-adrenoceptor blocker therapy experienced slightly poorer survival (HR = 1.18, 95% CI 1.04, 1.33 for all β-adrenoceptor blockers; HR = 1.21, 95% CI 0.94, 1.55 for non-selective β-adrenoceptor blockers). This poorer overall survival was explained by patients with pancreatic and prostate cancer with no evidence of an effect on survival for patients with lung, breast or colorectal cancer. Analysis in a cancer-free matched parallel cohort did not suggest selection bias masked a beneficial effect.

CONCLUSION

Our study does not support the hypothesis that β-adrenoceptor blockers improve survival for common cancers.     

Drug-disease interaction: Crohn's disease elevates verapamil plasma concentrations but reduces response to the drug proportional to disease activity

AIM

Inflammation is involved in the pathogenesis of cardiovascular diseases that includes reduced response to pharmacotherapy due to altered pharmacokinetics and pharmacodynamics. It is not known if these effects exist in general in all inflammatory conditions. It also remains unknown whether in a given population the effect is a function of disease severity. We investigated whether pharmacokinetics and pharmacodynamics of a typical calcium channel inhibitor are influenced by Crohn''s disease (CD), a disease for which the disease severity can be readily ranked.

METHODS

We administered 80 mg verapamil orally to (i) healthy control subjects (n = 9), (ii) patients with clinically quiescent CD (n = 22) and (iii) patients with clinically active CD (n = 14). Serial analysis of verapamil enantiomers (total and plasma unbound), blood pressure and electrocardiograms were recorded over 8 h post dose. The severity of CD was measured using the Harvey-Bradshaw Index.

RESULTS

CD substantially and significantly increased plasma verapamil concentration and in a stereoselective fashion (S, 9-fold; R, 2-fold). The elevated verapamil concentration, however, failed to result in an increased verapamil pharmacodynamic effect so that the patients with elevated verapamil concentration demonstrated no significant increase in response measured as PR interval and blood pressure. Instead, the greater the disease severity, the lower was the drug potency to prolong PR interval (r = 0.86, P < 0.0006),

CONCLUSIONS

CD patients with severe disease may not respond to cardiovascular therapy with calcium channel blockers. Reducing the severity increases response despite reduced drug concentration. This observation may have therapeutic implication beyond the disease and the drug studies herein.     

Acceptability and characteristics of 124 human bioequivalence studies with active substances classified according to the Biopharmaceutic Classification System

AIM

The aim of this study was to evaluate the acceptability of 124 bioequivalence (BE) studies with 80 active substances categorized according to the Biopharmaceutics Classification System (BCS) in order to establish if there were different probabilities of proving BE between the different BCS classes.

METHODS

We evaluated the differences between pharmaceutical products with active substances from different BCS classes in terms of acceptability, number of subjects in the study (n), the point estimates, and intra- and inter-subject coefficients of variation data from BE studies with generic products.

RESULTS

Out of 124 BE studies 89 (71.77%) were performed with pharmaceutical products containing active substances classified by the BCS. In all BCS classes there were non-bioequivalent pharmaceutical products: 4 out of 26 (15.38%) in class 1, 14 out of 28 (50%) in class 2, 3 out of 22 (13.63%) in class 3 and 1 out of 13 (7.69%) in class 4. When we removed those pharmaceutical products in which intra-subject variability was higher than predicted (2 in class 1 active substances, 9 in class 2 and 2 in class 3) there were still non-BE pharmaceutical products in classes 1, 2 and 3.

CONCLUSIONS

Comparisons between pharmaceutical products with active substances from the four BCS classes have not allowed us to define differential characteristics of each class in terms of n, inter and intra-subject variability for C_max or AUC. Despite the usually employed test dissolution methodology proposed as quality control, pharmaceutical products with active substances from the four classes of BCS showed non-BE studies.     

A randomized trial of the safety,pharmacokinetics and pharmacodynamics of edoxaban,an oral factor Xa inhibitor,following a switch from warfarin

Aims

To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of edoxaban, an oral direct factor Xa inhibitor, in healthy subjects switching from warfarin.

Methods

Seventy-two subjects were randomized to edoxaban 60 mg once daily (n = 48) or matching placebo (n = 24) for 5 days at 24 h after the last dose of warfarin treatment (INR 2.0 to 3.0). Safety/tolerability was the primary outcome measure. Pharmacokinetics, INR, aPTT, anti-FXa, thrombin generation and other coagulation assays were assessed.

Results

Seventy-two subjects were randomized and 64 subjects received at least one dose of edoxaban (n = 43) or placebo (n = 21) after achieving a target INR of 2.0 to 3.0 on warfarin treatment. Edoxaban 60 mg administered 24 h post-warfarin appeared to be safe and well tolerated. Adverse events were similar across treatments. For bleeding-related adverse events, eight subjects tested positive for faecal occult blood, five subjects during warfarin treatment and three subjects during edoxaban treatment. The mean (SD) baseline (post-dose of warfarin) INR was 2.31 (0.193) which increased to 3.84 (0.744) over 2 h during the edoxaban treatment (P < 0.0001 vs. placebo), returning to post-warfarin baseline within 12 h. A similar time course of effects for the other coagulation assays was observed in accordance with the drugs'' mechanisms of action.

Conclusion

In this study of healthy subjects, edoxaban administered 24 h after the last dose of warfarin was safe and well tolerated with transient increases across the various coagulation assays above post-warfarin baseline levels.     

The pharmacokinetics of peginterferon lambda-1a following single dose administration to subjects with impaired renal function

Aims

This open label study was conducted to assess the effect of renal impairment (RI) on the pharmacokinetics (PK) of peginterferon lambda-1a (Lambda).

Methods

Subjects (age 18–75 years, BMI 18–35 kg m^–2) were enrolled into one of five renal function groups: normal (n = 12), mild RI (n = 8), moderate RI (n = 8), severe RI (n = 7), end-stage renal disease (ESRD, n = 8) based on estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease (MDRD) equation. Subjects received a single dose of Lambda (180 µg) subcutaneously on day 1 followed by PK serum sample collections through day 29. Safety, tolerability and immunogenicity data were collected through day 43. PK parameters were estimated and summarized by group. Geometric mean ratios (GMR) and 90% confidence intervals (CIs) were calculated between normal and RI groups.

Results

With decreasing eGFR, Lambda exposure (C_max, AUC) increased while apparent clearance (CL/F) and apparent volume of distribution (V/F) decreased. Relative to subjects with normal renal function (geometric mean AUC = 99.5 ng ml^–1 h), Lambda exposure estimates (AUC) were slightly increased in the mild RI group (geometric mean [90% CI]: 1.20 [0.82, 1.77]) and greater in the moderate (1.95 [1.35, 2.83]), severe RI (1.95 [1.30, 2.93]) and ESRD (1.88 [1.30, 2.73]) groups. Lambda was generally well tolerated.

Conclusions

The results demonstrated that RI reduces the clearance of Lambda and suggests that dose modifications may not be required in patients with mild RI but may be required in patients with moderate to severe RI or ESRD.     

Simultaneous oral therapeutic and intravenous 14C‐microdoses to determine the absolute oral bioavailability of saxagliptin and dapagliflozin

Aim

To determine the absolute oral bioavailability (F_p.o.) of saxagliptin and dapagliflozin using simultaneous intravenous ¹⁴C‐microdose/therapeutic oral dosing (i.v.micro + oraltherap).

Methods

The F_p.o. values of saxagliptin and dapagliflozin were determined in healthy subjects (n = 7 and 8, respectively) following the concomitant administration of single i.v. micro doses with unlabelled oraltherap doses. Accelerator mass spectrometry and liquid chromatography‐tandem mass spectrometry were used to quantify the labelled and unlabelled drug, respectively.

Results

The geometric mean point estimates (90% confidence interval) F_p.o. values for saxagliptin and dapagliflozin were 50% (48, 53%) and 78% (73, 83%), respectively. The i.v.micro had similar pharmacokinetics to oraltherap.

Conclusions

Simultaneous i.v.micro + oraltherap dosing is a valuable tool to assess human absolute bioavailability.     

Effect of hepatic impairment on the pharmacokinetics and pharmacodynamics of a single dose of rivaroxaban,an oral,direct Factor Xa inhibitor

Aim

This study investigated the effects of hepatic impairment on the pharmacokinetics and pharmacodynamics of a single dose of rivaroxaban (10 mg), an oral, direct Factor Xa inhibitor.

Method

This single centre, non-randomized, non-blinded study included subjects with mild (n = 8) or moderate hepatic impairment (n = 8), according to the Child–Pugh classification, and gender-matched healthy subjects (n = 16).

Results

Rivaroxaban was well tolerated irrespective of hepatic function. Mild hepatic impairment did not significantly affect the pharmacokinetics or pharmacodynamics of rivaroxaban, compared with healthy subjects. However, in subjects with moderate hepatic impairment, total body clearance was decreased, leading to a significant increase in the area under the plasma concentration–time curve (AUC). The least-squares (LS)-mean values for AUC were 1.15-fold [90% confidence interval (CI) 0.85, 1.57] and 2.27-fold (90% CI 1.68, 3.07) higher in subjects with mild and moderate hepatic impairment, respectively, than in healthy subjects. Consequently, the pharmacodynamic responses were significantly enhanced in subjects with moderate hepatic impairment. For inhibition of Factor Xa, increases in the area under the effect–time curve and the maximum effect were observed, with LS-mean ratios of 2.59 and 1.24, respectively, vs. healthy subjects. Prolongation of prothrombin time was similar in healthy subjects and those with mild hepatic impairment, but was significantly enhanced in those with moderate hepatic impairment.

Conclusion

Moderate (but not mild) hepatic impairment reduced total body clearance of rivaroxaban after a single 10 mg dose, leading to increased rivaroxaban exposure and pharmacodynamic effects.     

Exposure?response modelling for empagliflozin,a sodium glucose cotransporter 2 (SGLT2) inhibitor,in patients with type 2 diabetes

Aims

To provide model-based clinical development decision support including dose selection guidance for empagliflozin, an orally administered sodium glucose cotransporter 2 inhibitor, through developed exposure−response (E−R) models for efficacy and tolerability in patients with type 2 diabetes mellitus (T2DM).

Methods

Five randomized, placebo-controlled, multiple oral dose studies of empagliflozin in patients with T2DM (n = 974; 1–100 mg once daily, duration ≤12 weeks) were used to develop E−R models for efficacy (glycosylated haemoglobin [HbA_1c], fasting plasma glucose [FPG] and urinary glucose excretion). Two studies (n = 748, 12 weeks) were used to evaluate tolerability E−R.

Results

The efficacy model predicted maximal decreases in FPG and HbA_1c of 16% and 0.6%, respectively, assuming a baseline FPG concentration of 8 mm (144 mg dl⁻¹) and 10–25 mg every day empagliflozin targeted 80–90% of these maximums. Increases in exposure had no effect on incidence rates of hypoglycaemia (n = 4), urinary tract infection (n = 17) or genital/vulvovaginal-related (n = 16) events, although low prevalence rates may have precluded more accurate evaluation.

Conclusions

E−R analyses indicated that 10 and 25 mg once daily empagliflozin doses achieved near maximal glucose lowering efficacy.