AimAssess the pharmacodynamics of lixisenatide once daily (QD) versus liraglutide QD in type 2 diabetes insufficiently controlled on metformin.MethodsIn this 28-day, randomized, open-label, parallel-group, multicentre study (NCT01175473), patients (mean HbA1c 7.3%) received subcutaneous lixisenatide QD (10 µg weeks 1–2, then 20 µg; n = 77) or liraglutide QD (0.6 mg week 1, 1.2 mg week 2, then 1.8 mg; n = 71) 30 min before breakfast. Primary endpoint was change in postprandial plasma glucose (PPG) exposure from baseline to day 28 during a breakfast test meal.ResultsLixisenatide reduced PPG significantly more than liraglutide [mean change in AUC0:30–4:30h: −12.6 vs. −4.0 h·mmol/L, respectively; p < 0.0001 (0:30 h = start of meal)]. Change in maximum PPG excursion was −3.9 mmol/l vs. −1.4 mmol/l, respectively (p < 0.0001). More lixisenatide-treated patients achieved 2-h PPG <7.8 mmol/l (69% vs. 29%). Changes in fasting plasma glucose were greater with liraglutide (−0.3 vs. −1.3 mmol/l, p < 0.0001). Lixisenatide provided greater decreases in postprandial glucagon (p < 0.05), insulin (p < 0.0001) and C-peptide (p < 0.0001). Mean HbA1c decreased in both treatment groups (from 7.2% to 6.9% with lixisenatide vs. 7.4% to 6.9% with liraglutide) as did body weight (−1.6 kg vs. −2.4 kg, respectively). Overall incidence of adverse events was lower with lixisenatide (55%) versus liraglutide (65%), with no serious events or hypoglycaemia reported.ConclusionsOnce daily prebreakfast lixisenatide provided a significantly greater reduction in PPG (AUC) during a morning test meal versus prebreakfast liraglutide. Lixisenatide provided significant decreases in postprandial insulin, C-peptide (vs. an increase with liraglutide) and glucagon, and better gastrointestinal tolerability than liraglutide.
Background Alirocumab, a monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9), lowers plasma low density lipoprotein cholesterol (LDL-C) and apolipoprotein B100 (apoB). Although studies in mice and cells have identified increased hepatic LDL receptors as the basis for LDL lowering by PCSK9 inhibitors, there have been no human studies characterizing the effects of PCSK9 inhibitors on lipoprotein metabolism. In particular, it is not known if inhibition of PCSK9 has any effects on very low density lipoprotein (VLDL) or intermediate density lipoprotein (IDL) metabolism. Inhibition of PCSK9 also results in reductions of plasma Lp(a) levels. The regulation of plasma Lp(a) levels, including the role of LDL receptors (LDLRs) in the clearance of Lp(a), is poorly defined, and there have been no mechanistic studies of the Lp(a) lowering by alirocumab in humans. Methods Eighteen (10F, 8M) participants completed a placebo-controlled, two-period study. They received 2 doses of placebo, 2 weeks apart, followed by 5 doses of 150 mg of alirocumab, 2 weeks apart. At the end of each period, fractional clearance rates (FCR) and production rates (PR) of apoB and apo(a) were determined. In 10 participants, postprandial triglycerides (TG) and apoB48 levels were measured. Results Alirocumab reduced ultracentrifugally isolated LDL-C by 55.1%, LDL-apoB by 56.3%, and plasma Lp(a) by 18.7%. The fall in LDL-apoB was due to an 80.4% increase in LDL-apoB FCR and a 23.9% reduction in LDL-apoB PR. The latter was associated with a 46.1% increase in IDL-apoB FCR coupled with a 27.2% decrease in conversion of IDL to LDL. The FCR of apo(a) tended to increase (24.6%) without any change in apo(a) PR. Alirocumab had no effects on FCRs or PRs of VLDL-apoB and VLDL-TG, or on postprandial plasma TG or apoB48 concentrations. Conclusions Alirocumab decreased LDL-C and LDL-apoB by increasing IDL- and LDL-apoB FCRs, and decreasing LDL-apoB PR. These results are consistent with increases in LDLRs available to clear IDL and LDL from blood during PCSK9 inhibition. The possible increase in apo(a) FCR during alirocumab treatment suggests that increased LDLRs may also play a role in the reduction of plasma Lp(a). Clinical Trials Registration Clinical trials.gov # NCT01959971
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Numerous cocktails using concurrent administration of several cytochrome P450 (CYP) isoform‐selective probe drugs have been reported to investigate drug–drug interactions in vivo.• This approach has several advantages: characterize the inhibitory or induction potential of compounds in development toward the CYP enzymes identified in vitro in an in vivo situation, assess several enzymes in the same trial, and have complete in vivo information about potential CYP‐based drug interactions. WHAT THIS STUDY ADDS • This study describes a new cocktail containing five probe drugs that has never been published.• This cocktail can be used to test the effects of a new chemical entity on multiple CYP isoforms in a single clinical study: CYP1A2 (caffeine), CYP2C9 (warfarin), CYP2C19 (omeprazole), CYP2D6 (metoprolol), and CYP3A (midazolam) and was designed to overcome potential liabilities of other reported cocktails.AIMS To assess the pharmacokinetics (PK) of selective substrates of CYP1A2 (caffeine), CYP2C9 (S‐warfarin), CYP2C19 (omeprazole), CYP2D6 (metoprolol) and CYP3A (midazolam) when administered orally and concurrently as a cocktail relative to the drugs administered alone.METHODS This was an open‐label, single‐dose, randomized, six‐treatment six‐period six‐sequence William's design study with a wash‐out of 7 or 14 days. Thirty healthy male subjects received 100 mg caffeine, 100 mg metoprolol, 0.03 mg kg−1 midazolam, 20 mg omeprazole and 10 mg warfarin individually and in combination (cocktail). Poor metabolizers of CYP2C9, 2C19 and 2D6 were excluded. Plasma samples were obtained up to 48 h for caffeine, metoprolol and omeprazole, 12 h for midazolam, 312 h for warfarin and the cocktail. Three different validated liquid chromatography tandem mass spectrometry methods were used. Noncompartmental PK parameters were calculated. Log‐transformed Cmax, AUClast and AUC for each analyte were analysed with a linear mixed effects model with fixed term for treatment, sequence and period, and random term for subject within sequence. Point estimates (90% CI) for treatment ratios (individual/cocktail) were computed for each analyte Cmax, AUClast and AUC.RESULTS There was no PK interaction between the probe drugs when administered in combination as a cocktail, relative to the probes administered alone, as the 90% CI of the PK parameters was within the prespecified bioequivalence limits of 0.80, 1.25.CONCLUSION The lack of interaction between probes indicates that this cocktail could be used to evaluate the potential for multiple drug–drug interactions in vivo.
BackgroundAlirocumab undergoes target‐mediated clearance via binding of proprotein convertase subtilisin/kexin type 9 (PCSK9). Statins increase PCSK9 levels; the effects of nonstatin lipid‐lowering therapies are unclear. Every‐4‐weeks dosing of alirocumab may be appropriate for some patients in absence of background statin but is not yet approved.Methods and ResultsLow‐density lipoprotein cholesterol (LDL‐C), PCSK9, and alirocumab levels were assessed in subjects (LDL‐C >130 mg/dL, n=24/group) after a 4‐week run‐in taking oral ezetimibe, fenofibrate, or ezetimibe placebo, when alirocumab 150 mg every 4 weeks (days 1, 29, and 57) was added. Maximal mean LDL‐C reductions from day −1 baseline (prealirocumab) occurred on day 71 in all groups: alirocumab plus placebo, 47.4%; alirocumab plus ezetimibe, 56.6%; and alirocumab plus fenofibrate, 54.3%. LDL‐C reductions were sustained through day 85 with alirocumab plus placebo (47.0%); the duration of effect was slightly diminished at day 85 versus day 71 with ezetimibe (49.6%) or fenofibrate combinations (43.2%). Free PCSK9 concentrations were lowest at day 71 in all groups, then increased over time; by day 85, free PCSK9 concentrations were higher, and alirocumab levels lower, with alirocumab plus fenofibrate, and to a lesser extent alirocumab plus ezetimibe, versus alirocumab plus placebo.ConclusionsAlirocumab 150 mg every 4 weeks produced maximal LDL‐C reductions of 47% in combination with placebo and 54% to 57% in combination with ezetimibe or fenofibrate. The oral lipid‐lowering therapies appear to increase PCSK9 levels, leading to increased alirocumab clearance. Although the duration of effect was modestly diminished with alirocumab plus ezetimibe/fenofibrate versus placebo, the effect was less than observed in trials with background statins, and it would not preclude the use of alirocumab every 4 weeks in patients taking these nonstatin lipid‐lowering therapies concomitantly.Clinical Trial Registration URL: http://www.Clinicaltrials.gov. Unique identifier: NCT01723735.
Currently, few elderly women have a measurement of bone mineral density (BMD). The aim of this study was to assess the potential value of a two-step screening process to identify the elderly women who are at greatest risk of fracture because of very low BMD: (1) use simple clinical criteria to select women who are highly likely to have a very low BMD and (2) measure the BMD of the women so selected. We used baseline data from 6958 women aged 75 years or older who were participants in the EPIDOS prospective study of risk factors for hip fracture. The outcome variable was very low BMD measured at the femoral neck by dual-energy X-ray absorptiometry and defined as a T-score < or = -3.5. The factors most predictive of very low BMD were low weight, history of fracture after the age of 50 years, slow gait, balance impairment, low grip strength, and dependence for instrumental activities of daily living. A score based on the risk function including these factors has a sensitivity of 80% at the median cut-off. Hence, by measuring the BMD of only half the population, 80% of the women with very low BMD can be identified. Weight is the strongest determinant of very low BMD and has approximately the same sensitivity as the complete score. In conclusion, a risk score for very low BMD based on simple criteria such as weight could be a useful clinical tool to select elderly women for bone densitometry.
AimsWe investigated the relative pharmacokinetics, pharmacodynamics, and safety of the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor alirocumab following injection at three different sites.MethodsSixty healthy subjects (39 male, 21 female; age 20–45 years) were randomized to receive a single subcutaneous injection of alirocumab 75 mg via 1-mL prefilled pen into the abdomen, upper arm, or thigh (NCT01785329). Subjects were followed for 85 days ± 2 days following study drug administration. Pharmacokinetic (PK) parameters for the systemic exposure of alirocumab were calculated, and levels of free PCSK9 were assessed. Percentage changes from baseline in LDL-C were compared between injection site groups using linear mixed-effects models.ResultsAlirocumab concentration–time profiles were similar, and free PCSK9 levels were reduced to approximately zero between Day 3 and Day 4 postinjection in all groups. LDL-C levels reached nadir on Day 15 postinjection in all groups with mean percentage reductions of 48.4% (abdomen), 39.5% (upper arm), and 45.6% (thigh) at this time point. A similar effect on LDL-C levels was seen across the entire time course of the study at all three injection sites. Treatment-emergent adverse events were experienced by 8/20 (abdomen), 11/20 (upper arm), and 13/20 (thigh) subjects. There were 2 mild/transient injection site reactions. There were no serious adverse events.DiscussionA single subcutaneous administration of alirocumab 75 mg via prefilled pen was well tolerated with similar pharmacokinetics and pharmacodynamics when injected into the abdomen, upper arm, or thigh.ConclusionThese results suggest that alirocumab can be interchangeably injected in the abdomen, upper arm, or thigh.
AIMCannabinoid receptor type 1 (CB1) antagonists have been developed for the treatment of obesity and associated risk factors. Surinabant is a high affinity CB1 antagonist in vitro. The aim of this study was to assess the magnitude of inhibition by surinabant of CNS effects and heart rate induced by D 9 -tetrahydrocannabinol (THC) in humans. METHODSThis was a double-blind, placebo-controlled, randomized, four period six sequence crossover study. Thirty healthy young male occasional cannabis users (<1 per week) were included. A single oral dose of surinabant (5, 20 or 60 mg) or placebo was administered followed 1.5 h later by four intrapulmonary THC doses (2, 4, 6 and 6 mg) or vehicle, administered at 1 h intervals. The wash-out period was 14-21 days. Subjective and objective pharmacodynamic (PD) measurements were performed. A population PK-PD model for THC and surinabant quantified PK and PD effects. RESULTSSurinabant 20 and 60 mg inhibited all THC-induced PD effects in a similar range for both doses with inhibition ratios ranging from 68.3% (95% CI = 32.5, 104.2; heart rate) to 91.1% (95% CI = 30.3, 151.8; body sway). IC50 ranged from 22.0 ng ml -1 [relative standard error (RSE) = 45.2%; body sway] to 58.8 ng ml -1 (RSE = 44.2%; internal perception). Surinabant 5 mg demonstrated no significant effects. CONCLUSIONSThe dose-related inhibition by surinabant, without any effect of its own, suggests that this compound behaves as a CB1 receptor antagonist in humans at these concentrations. A single surinabant dose between 5 to 20 mg and above was able to antagonize THC-induced effects in humans. WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• Rimonabant was the first cannabinoid receptor type 1 (CB1) inverse agonist that reached the market. However, with the doses used in patients, it caused severe side effects. We wanted to investigate the dose-effect profile and the effective dose range of surinabant, a new CB1 antagonist in healthy subjects. WHAT THIS STUDY ADDS• This study provides insight into the effective surinabant dose range in healthy subjects using a D 9 -tetrahydrocannabinol (THC) challenge test. Surinabant is able to inhibit various tests, such as heart rate, body sway and feeling high. In our model, surinabant is already maximally effective at single doses of 20 mg, and possibly even below.
SAR247799 is a selective G-protein-biased sphingosine-1 phosphate receptor-1 (S1P 1) agonist with potential to restore endothelial function in vascular pathologies. SAR247799, a first-in-class molecule differentiated from previous S1P 1-desensitizing molecules developed for multiple sclerosis, can activate S1P 1 without desensitization and consequent lymphopenia. The aim was to characterize SAR247799 for its safety, tolerability, pharmacokinetics and pharmacodynamics (activation and desensitization). Methods: SAR247799 was administered orally to healthy subjects in a double-blind, randomized, placebo-controlled study with single (2.5-37.5 mg) or 2-week once-daily (0.5-15 mg) doses. An open-label single dose pilot food-interaction arm with 10 mg SAR247799 in cross-over design was also performed. Results: SAR247799 was well tolerated and, at the higher end of the dose ranges, caused the expected dose-dependent pharmacodynamics associated with S1P 1 activation (heart rate reduction) and S1P 1 desensitization (lymphocyte count reduction). SAR247799 demonstrated dose-proportional increases in exposure and was eliminated with an apparent terminal half-life of 31.2-33.1 hours. Food had a small effect on the pharmacokinetics of SAR247799. SAR247799 had a low volume of distribution (7-23 L), indicating a potential to achieve dose separation for endothelial vs cardiac S1P 1 activation pharmacology. A supratherapeutic dose (10 mg) of SAR247799 produced sustained heart rate reduction over 14 days, demonstrating
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