Biomarkers of platelet activation and cardiovascular risk in the DAPT trial.

Prolonged use of dual antiplatelet therapy (DAPT) post-percutaneous coronary intervention (PCI) has been shown to reduce the risk of major adverse cardiovascular events (MACE), but with increased bleeding. It remains unknown whether biomarkers of platelet activation may be useful for identifying patients at increased risk of MACE. The DAPT study was a randomized trial of 12 versus 30 months of DAPT in patients who underwent PCI. Serum biomarkers [myeloid-related protein (MRP)-8/14, P-selectin, soluble CD-40 ligand (sCD40L)] were assessed in 1399 patients early post-PCI. On-treatment platelet reactivity index (PRI) using VASP phosphorylation was assessed in 443 patients randomized to continued DAPT at 1 year. MACE was defined as CV death, MI, or ischemic stroke. Multivariable models were adjusted for baseline characteristics, index event, and stent type. A stepwise increase in the risk of MACE was observed with increasing tertiles of both MRP-8/14 and P-selectin (p-trend = 0.04 for both). After multivariable adjustment, the adjusted HR (95% CI) for MACE in patients in the top tertile was 1.94 (1.14-3.30) for MRP-8/14 and 1.62 (0.99-2.64) for P-selectin. In contrast, baseline sCD40L was not associated with CV risk. Among patients randomized to continued DAPT, higher on-treatment platelet reactivity was not significantly associated with risk of MACE (p-trend = 0.32; adj-HR T3 vs. T1 1.54, 95% CI 0.20-12.18) or bleeding (P-trend = 0.17; adj-HR 0.25, 95% CI 0.05-1.21). MRP-8/14 and soluble P-selectin may be useful for identifying patients at increased risk of MACE after PCI. The utility of on-treatment platelet function testing requires further study.Clinical Trial Registration https://www.clinicaltrials.gov . Unique identifier NCT00977938.

Odanacatib for the treatment of postmenopausal osteoporosis: results of the LOFT multicentre, randomised, double-blind, placebo-controlled trial and LOFT Extension study.

BACKGROUND: Odanacatib, a cathepsin K inhibitor, reduces bone resorption while maintaining bone formation. Previous work has shown that odanacatib increases bone mineral density in postmenopausal women with low bone mass. We aimed to investigate the efficacy and safety of odanacatib to reduce fracture risk in postmenopausal women with osteoporosis. METHODS: The Long-term Odanacatib Fracture Trial (LOFT) was a multicentre, randomised, double-blind, placebo-controlled, event-driven study at 388 outpatient clinics in 40 countries. Eligible participants were women aged at least 65 years who were postmenopausal for 5 years or more, with a femoral neck or total hip bone mineral density T-score between -2·5 and -4·0 if no previous radiographic vertebral fracture, or between -1·5 and -4·0 with a previous vertebral fracture. Women with a previous hip fracture, more than one vertebral fracture, or a T-score of less than -4·0 at the total hip or femoral neck were not eligible unless they were unable or unwilling to use approved osteoporosis treatment. Participants were randomly assigned (1:1) to either oral odanacatib (50 mg once per week) or matching placebo. Randomisation was done using an interactive voice recognition system after stratification for previous radiographic vertebral fracture, and treatment was masked to study participants, investigators and their staff, and sponsor personnel. If the study completed before 5 years of double-blind treatment, consenting participants could enrol in a double-blind extension study (LOFT Extension), continuing their original treatment assignment for up to 5 years from randomisation. Primary endpoints were incidence of vertebral fractures as assessed using radiographs collected at baseline, 6 and 12 months, yearly, and at final study visit in participants for whom evaluable radiograph images were available at baseline and at least one other timepoint, and hip and non-vertebral fractures adjudicated as being a result of osteoporosis as assessed by clinical history and radiograph. Safety was assessed in participants who received at least one dose of study drug. The adjudicated cardiovascular safety endpoints were a composite of cardiovascular death, myocardial infarction, or stroke, and new-onset atrial fibrillation or flutter. Individual cardiovascular endpoints and death were also assessed. LOFT and LOFT Extension are registered with ClinicalTrials.gov (number NCT00529373) and the European Clinical Trials Database (EudraCT number 2007-002693-66). FINDINGS: Between Sept 14, 2007, and Nov 17, 2009, we randomly assigned 16 071 evaluable patients to treatment: 8043 to odanacatib and 8028 to placebo. After a median follow-up of 36·5 months (IQR 34·43-40·15) 4297 women assigned to odanacatib and 3960 assigned to placebo enrolled in LOFT Extension (total median follow-up 47·6 months, IQR 35·45-60·06). In LOFT, cumulative incidence of primary outcomes for odanacatib versus placebo were: radiographic vertebral fractures 3·7% (251/6770) versus 7·8% (542/6910), hazard ratio (HR) 0·46, 95% CI 0·40-0·53; hip fractures 0·8% (65/8043) versus 1·6% (125/8028), 0·53, 0·39-0·71; non-vertebral fractures 5·1% (412/8043) versus 6·7% (541/8028), 0·77, 0·68-0·87; all p<0·0001. Combined results from LOFT plus LOFT Extension for cumulative incidence of primary outcomes for odanacatib versus placebo were: radiographic vertebral fractures 4·9% (341/6909) versus 9·6% (675/7011), HR 0·48, 95% CI 0·42-0·55; hip fractures 1·1% (86/8043) versus 2·0% (162/8028), 0·52, 0·40-0·67; non-vertebral fractures 6·4% (512/8043) versus 8·4% (675/8028), 0·74, 0·66-0·83; all p<0·0001. In LOFT, the composite cardiovascular endpoint of cardiovascular death, myocardial infarction, or stroke occurred in 273 (3·4%) of 8043 patients in the odanacatib group versus 245 (3·1%) of 8028 in the placebo group (HR 1·12, 95% CI 0·95-1·34; p=0·18). New-onset atrial fibrillation or flutter occurred in 112 (1·4%) of 8043 patients in the odanacatib group versus 96 (1·2%) of 8028 in the placebo group (HR 1·18, 0·90-1·55; p=0·24). Odanacatib was associated with an increased risk of stroke (1·7% [136/8043] vs 1·3% [104/8028], HR 1·32, 1·02-1·70; p=0·034), but not myocardial infarction (0·7% [60/8043] vs 0·9% [74/8028], HR 0·82, 0·58-1·15; p=0·26). The HR for all-cause mortality was 1·13 (5·0% [401/8043] vs 4·4% [356/8028], 0·98-1·30; p=0·10). When data from LOFT Extension were included, the composite of cardiovascular death, myocardial infarction, or stroke occurred in significantly more patients in the odanacatib group than in the placebo group (401 [5·0%] of 8043 vs 343 [4·3%] of 8028, HR 1·17, 1·02-1·36; p=0·029, as did stroke (2·3% [187/8043] vs 1·7% [137/8028], HR 1·37, 1·10-1·71; p=0·0051). INTERPRETATION: Odanacatib reduced the risk of fracture, but was associated with an increased risk of cardiovascular events, specifically stroke, in postmenopausal women with osteoporosis. Based on the overall balance between benefit and risk, the study's sponsor decided that they would no longer pursue development of odanacatib for treatment of osteoporosis. FUNDING: Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc, Kenilworth, NJ, USA.

Transition of patients from blinded study drug to open-label anticoagulation: the ENGAGE AF-TIMI 48 trial.

BACKGROUND: At the end of 2 previous trials, an excess of stroke and bleeding was observed in patients with AF randomized to a new oral anticoagulant (NOAC) who transitioned to a vitamin K antagonist (VKA). OBJECTIVES: The ENGAGE AF-TIMI 48 (Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48) trial compared once-daily edoxaban to warfarin for stroke prevention in patients with AF. An end-of-trial transition plan was developed to minimize the risks of stroke due to inadequate anticoagulation and bleeding from excessive anticoagulation during this critical period. METHODS: All patients on the blinded study drug at the trial's conclusion were included in this analysis. In pre-specified analyses, stroke, bleeding, and death that occurred through 30 days after the end-of-trial visit were stratified by randomized treatment allocation and open-label anticoagulant selected post-trial. RESULTS: Of the 13,642 patients taking the blinded study drug at the end of the trial, 9,304 (68.2%) were transitioned to open-label VKA and 4,258 patients (31.2%) to an NOAC. There were 21 strokes evenly distributed across the 3 randomized treatment arms: warfarin 7 (1.90%/year), edoxaban high dose 7 (1.89%/year), edoxaban low dose 7 (1.85%/year). Major bleeding was also similar across the 3 treatment arms: warfarin 11 (2.98%/year), edoxaban high dose 10 (2.69%/year), edoxaban low dose 18 (4.76%/year). In patients transitioned to VKA, 85% of patients had at least 1 INR ≥ 2 by day 14 after the transition and 99% by day 30. CONCLUSIONS: The ENGAGE AF-TIMI 48 transition plan protected patients from an excess of thrombotic and bleeding events and should be helpful in clinical practice when patients are transitioned between oral anticoagulants. (Global Study to Assess the Safety and Effectiveness of Edoxaban [DU-176b] vs Standard Practice of Dosing With Warfarin in Patients With Atrial Fibrillation [EngageAFTIMI48]; NCT00781391).

Bone loss after bariatric surgery: discordant results between DXA and QCT bone density.

Several studies, using dual-energy X-ray absorptiometry (DXA), have reported substantial bone loss after bariatric surgery. However, profound weight loss may cause artifactual changes in DXA areal bone mineral density (aBMD) results. Assessment of volumetric bone mineral density (vBMD) by quantitative computed tomography (QCT) may be less susceptible to such artifacts. We assessed changes in BMD of the lumbar spine and proximal femur prospectively for 1 year using DXA and QCT in 30 morbidly obese adults undergoing Roux-en-Y gastric bypass surgery and 20 obese nonsurgical controls. At 1 year, subjects who underwent gastric bypass surgery lost 37 ± 2 kg compared with 3 ± 2 kg lost in the nonsurgical controls (p < 0.0001). Spine BMD declined more in the surgical group than in the nonsurgical group whether assessed by DXA (-3.3 versus -1.1%, p = 0.034) or by QCT (-3.4 versus 0.2%, p = 0.010). Total hip and femoral neck aBMD declined significantly in the surgical group when assessed by DXA (-8.9 versus -1.1%, p < 0.0001 for the total hip and -6.1 versus -2.0%, p = 0.002 for the femoral neck), but no changes in hip vBMD were noted using QCT. Within the surgical group, serum P1NP and CTX levels increased by 82% ± 10% and by 220% ± 22%, respectively, by 6 months and remained elevated over 12 months (p < 0.0001 for all). Serum calcium, vitamin D, and PTH levels remained stable in both groups. We conclude that moderate vertebral bone loss occurs in the first year after gastric bypass surgery. However, striking declines in DXA aBMD at the proximal femur were not confirmed with QCT vBMD measurements. These discordant results suggest that artifacts induced by large changes in body weight after bariatric surgery affect DXA and/or QCT measurements of bone, particularly at the hip.

An internet-based virtual coach to promote physical activity adherence in overweight adults: randomized controlled trial.

BACKGROUND: Addressing the obesity epidemic requires the development of effective, scalable interventions. Pedometers and Web-based programs are beneficial in increasing activity levels but might be enhanced by the addition of nonhuman coaching. OBJECTIVES: We hypothesized that a virtual coach would increase activity levels, via step count, in overweight or obese individuals beyond the effect observed using a pedometer and website alone. METHODS: We recruited 70 participants with a body mass index (BMI) between 25 and 35 kg/m(2) from the Boston metropolitan area. Participants were assigned to one of two study arms and asked to wear a pedometer and access a website to view step counts. Intervention participants also met with a virtual coach, an automated, animated computer agent that ran on their home computers, set goals, and provided personalized feedback. Data were collected and analyzed in 2008. The primary outcome measure was change in activity level (percentage change in step count) over the 12-week study, split into four 3-week time periods. Major secondary outcomes were change in BMI and participants' satisfaction. RESULTS: The mean age of participants was 42 years; the majority of participants were female (59/70, 84%), white (53/70, 76%), and college educated (68/70, 97%). Of the initial 70 participants, 62 completed the study. Step counts were maintained in intervention participants but declined in controls. The percentage change in step count between those in the intervention and control arms, from the start to the end, did not reach the threshold for significance (2.9% vs -12.8% respectively, P = .07). However, repeated measures analysis showed a significant difference when comparing percentage changes in step counts between control and intervention participants over all time points (analysis of variance, P = .02). There were no significant changes in secondary outcome measures. CONCLUSIONS: The virtual coach was beneficial in maintaining activity level. The long-term benefits and additional applications of this technology warrant further study. TRIAL REGISTRATION: ClinicalTrials.gov NCT00792207; http://clinicaltrials.gov/ct2/show/NCT00792207 (Archived by WebCite at http://www.webcitation.org/63sm9mXUD).