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Coronary artery disease (CAD) remains the leading cause of adult mortality globally. Targeting known modifiable risk factors has had substantial benefit, but there remains a need for new approaches. Improvements in invasive and noninvasive imaging techniques have enabled an increasing recognition of distinct quantitative phenotypes of coronary atherosclerosis that are prognostically relevant. There are marked differences in plaque phenotype, from the high-risk, lipid-rich, thin-capped atheroma to the low-risk, quiescent, eccentric, nonobstructive calcified plaque. Such distinct phenotypes reflect different pathophysiologic pathways and are associated with different risks for acute ischemic events. Noninvasive coronary imaging techniques, such as computed tomography, positron emission tomography, and coronary magnetic resonance imaging, have major potential to accelerate cardiovascular drug development, which has been affected by the high costs and protracted timelines of cardiovascular outcome trials. This may be achieved through enrichment of high-risk phenotypes with higher event rates or as primary end points of drug efficacy, at least in phase 2 trials, in a manner historically performed through intravascular coronary imaging studies. Herein, we provide a comprehensive review of the current technology available and its application in clinical trials, including implications for sample size requirements, as well as potential limitations. In its effort to accelerate drug development, the US Food and Drug Administration has approved surrogate end points for 120 conditions, but not for CAD. There are robust data showing the beneficial effects of drugs, including statins, on CAD progression and plaque stabilization in a manner that correlates with established clinical end points of mortality and major adverse cardiovascular events. This, together with a clear mechanistic rationale for using imaging as a surrogate CAD end point, makes it timely for CAD imaging end points to be considered. We discuss the importance of global consensus on these imaging end points and protocols and partnership with regulatory bodies to build a more informed, sustainable staged pathway for novel therapies.

We report on a carbapenemase-producing hypervirulent Klebsiella pneumoniae (CP-hvKP) isolate collected from a U.S. patient at an outpatient clinic. The isolate was identified as K. pneumoniae serotype K1 sequence type 23 and included both a hypervirulence (with rmpA , rmpA2 iroBCDN , peg -344, and iucABCD-iutA genes) and a carbapenemase-encoding ( bla ) plasmid. The emergence of CP-hvKP underscores the importance of clinical awareness of this pathotype and the need for continued monitoring of CP-hvKP in the United States.KPC-2 ) plasmid. The emergence of CP-hvKP underscores the importance of clinical awareness of this pathotype and the need for continued monitoring of CP-hvKP in the United States., (This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.)

We performed detailed pharmacokinetic and pharmacodynamic modeling of REG1, an anticoagulation system composed of the direct factor IXa (FIXa) inhibitor pegnivacogin (RB006) and its matched active control agent anivamersen (RB007), with a focus on level of target inhibition to translate phase 1 results to phase 2 dose selection. We modeled early-phase clinical data relating weight-adjusted pegnivacogin dose and plasma concentration to prolongation of the activated partial thromboplastin time (aPTT). Using an in vitro calibration curve, percent FIXa inhibition was determined and related to aPTT prolongation and pegnivacogin dose and concentration. Similar methods were applied to relate anivamersen dose and level of reversal of pegnivacogin anticoagulation. Combined early-phase data suggested that ≥0.75 mg/kg pegnivacogin was associated with >99% inhibition of FIX activity and prolongation of plasma aPTT values ≈2.5 times above baseline, leading to selection of a 1 mg/kg dose for a phase 2a elective percutaneous coronary intervention study to achieve a high intensity of anticoagulation and minimize intersubject variability. Phase 2 validated our predictions, demonstrating 1 mg/kg pegnivacogin yielded plasma concentrations ≈25 μg/ml and >99% inhibition of FIX activity. The relationship between the anivamersen to pegnivacogin dose ratio and degree of pegnivacogin reversal was also validated. Our approach decreased the need for extensive dose-response studies, reducing the duration, complexity and cost of clinical development. The 1 mg/kg pegnivacogin dose and a range of anivamersen dose ratios are being tested in the phase 2b RADAR study (NCT00932100).