Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Mirikizumab Pharmacokinetics in Patients with Moderately to Severely Active Ulcerative Colitis: Results from Phase III LUCENT Studies

BACKGROUND AND OBJECTIVE

Mirikizumab is a humanized anti-interleukin-23-p19 monoclonal antibody being developed for ulcerative colitis and Crohn's disease. This analysis characterized mirikizumab pharmacokinetics using phase II and III trial data from patients with moderately to severely active ulcerative colitis.

METHODS

Serum pharmacokinetic data in patients receiving mirikizumab 50-1000 mg intravenously every 4 weeks as induction treatment and mirikizumab 200 mg subcutaneously every 4 or 12 weeks as maintenance treatment across three trials (N = 1362) were analyzed using non-linear mixed-effects modeling. Covariate effects on mirikizumab exposure were evaluated using simulation-based estimations.

RESULTS

Mirikizumab pharmacokinetics was best described by a linear two-compartment model with first-order absorption. Clearance, volume of distribution for central and peripheral compartments, and half-life were estimated at approximately 0.022 L/h (linear), 3.11 L and 1.69 L, and 9.5 days, respectively. Statistically significant effects of body weight and serum albumin levels on clearance, body weight on central and peripheral volumes of distribution, and body mass index on bioavailability were observed but effects were small relative to random inter-individual variability (% coefficient of variation: 18-64%). The subcutaneous bioavailability of mirikizumab was 48%.

CONCLUSIONS

Mirikizumab displayed pharmacokinetic characteristics typical of a monoclonal antibody where clearance increased with body weight and decreased with the albumin level, and bioavailability decreased with body mass index. These effects were small relative to random variability, indicating that a dose adjustment for patient factors is not required.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT02589665 (28 October, 2015), NCT03518086 (8 May, 2018), NCT03524092 (14 May, 2018).

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Efficacy and Safety of Continued Treatment With Mirikizumab in a Phase 2 Trial of Patients With Ulcerative Colitis

BACKGROUND & AIMS

Mirikizumab is an antibody against the p19 subunit of interleukin 23 that has demonstrated clinical efficacy and was well tolerated following 12 weeks of induction treatment in a phase 2 trial of patients with moderate to severe ulcerative colitis. We present results of the open-label extended induction period in patients who did not initially respond to treatment with mirikizumab.

METHODS

This study was a continuation of I6T-MC-AMAC, a double-blind trial, performed at 75 sites in 14 countries, in which patients with moderate to severe ulcerative colitis were randomly assigned to 12 weeks induction therapy with 50 mg, 200 mg, or 600 mg mirikizumab or placebo. Patients without a clinical response (a 9-point decrease in Mayo subscore of ≥2 points and ≥35% from baseline and either a decrease of rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1) at week 12 were offered the opportunity to participate in an open-label, extended induction study for another 12 weeks, in which they received either 600 mg intravenous mirikizumab (n = 20) or, following a protocol amendment, 1000 mg intravenous mirikizumab (n = 64) every 4 weeks. At week 24, patients with a clinical response continued the extension maintenance period and received 200 mg subcutaneous mirikizumab. Endpoints included clinical remission (Mayo subscores of 0 for rectal bleeding, 0 or 1 with a 1-point decrease from baseline), clinical response, endoscopic remission (Mayo endoscopic subscore of 0), or endoscopic improvement (endoscopic subscore of 0 or 1), at study weeks 24 and 52. Data were analysed for patients who received mirikizumab or placebo during the induction phase of the study.

RESULTS

Among participants who did not respond to induction mirikizumab, 50.0% of those who received the 12-week extension of 600 mg mirikizumab and 43.8% who received the extension of 1000 mg mirikizumab achieved a clinical response; 15.0% and 9.4% achieved clinical remission, respectively. Endoscopic improvement was achieved by 20.0% of subjects in the 600 mg mirikizumab group and 15.6% subjects in the 1000 mg mirikizumab group. Among initial nonresponders to mirikizumab who had clinical response at study week 24 and continued into maintenance therapy, 65.8% maintained the clinical response, 26.3% achieved clinical remission, and 34.2% had endoscopic improvement at week 52. No new safety concerns were identified.

CONCLUSIONS

Extended doses of mirikizumab (600 mg and 1000 mg) for an additional 12 weeks produce a clinical response in up to 50% of patients who did not have a clinical response to 12 weeks of induction doses (50 mg, 200 mg, or 600 mg). Most of the responders to the extended doses maintained clinical response for up to 52 weeks. Clinicaltrials.gov no: NCT02589665.

Limits on the Existence of sub-MeV Sterile Neutrinos from the Decay of ^{7}Be in Superconducting Quantum Sensors

Sterile neutrinos are natural extensions to the standard model of particle physics and provide a possible portal to the dark sector. We report a new search for the existence of sub-MeV sterile neutrinos using the decay-momentum reconstruction technique in the decay of ^{7}Be. The experiment measures the total energy of the ^{7}Li daughter atom from the electron capture decay of ^{7}Be implanted into sensitive superconducting tunnel junction (STJ) quantum sensors. This first experiment presents data from a single STJ operated at a low count rate for a net total of 28 days, and provides exclusion limits on sterile neutrinos in the mass range from 100 to 850 keV that improve upon previous work by up to an order of magnitude.

Observation of the pη^{'} Cusp in the New Precise Beam Asymmetry Σ Data for γp→pη

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748  MeV to W=2045  MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447  MeV (W=1896  MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

Direct Measurement of the ^{7}Be L/K Capture Ratio in Ta-Based Superconducting Tunnel Junctions

We report a high-statistics measurement of the L/K orbital electron capture ratio in ^{7}Be embedded in cryogenic Ta. The thin Ta film formed part of a high-resolution superconducting tunnel junction radiation detector that was used to identify the signals from different decay channels. The measured L/K capture ratio of 0.070(7) is significantly larger than the only previous measurement of this quantity and the theoretical predictions that include in-medium effects. This value is a uniquely sensitive probe of the 1s and 2s orbital overlaps with the nucleus and is of relevance to nuclear and atomic physics, as well as Li production in novae and other astrophysical scenarios. This is the first experiment that uses superconducting tunnel junctions for nuclear-recoil detection, opening a new experimental avenue for low-energy precision measurements with rare isotopes.

The first composite score predicting Digital Ulcers in systemic sclerosis patients using Clinical data, Imaging and Patient history-CIP-DUS

Background

Digital ulcers (DU) present a challenging complication in systemic sclerosis (SSc). The aim of this study was to combine clinical characteristics and imaging methods to a composite score for the prediction of DU in SSc patients.

Methods

Seventy-nine SSc patients received clinical examination, their patient history was taken and nailfold capillaroscopy (NC), colour Doppler ultrasonography (CDUS) and fluorescence optical imaging (FOI) of the hands were performed at baseline. Newly developed DU over a period of approximately 12 months were registered. We used criteria with area under the curve (AUC) of at least 0.6 in regard to the development of these new DU to create the score (CIP-DUS, clinical features, imaging, patient history—digital ulcer score).

Results

Twenty-nine percent of all SSc patients developed new DU during follow-up (48.1% diffuse, 18.4% limited SSc). Based on the cross-validated (cv) AUC, a weight (cvAUC > 0.6 and ≤ 0.65: 1; cvAUC > 0.65 and ≤ 0.7: 2; cvAUC > 0.7: 3) was assigned to each selected parameter. The performance of the final CIP-DUS was assessed with and without the CDUS/FOI component. For the scleroderma patterns in NC, three points were appointed to late, two to active and one point to early capillaroscopy pattern according to Cutolo et al. The CIP-DUS including the CDUS and FOI parameters resulted in a good diagnostic performance (AUC after cross-validation: 0.83, 95%CI 0.74 to 0.92) and was well calibrated (chi-square = 12.3, p = 0.58). The cut-off associated with the maximum of sensitivity and specificity was estimated at ≥ 10 points resulting in a sensitivity of 100% and specificity of 74% for new DU during follow-up. Excluding CDUS and FOI parameters leads to a non-statistically significant lower performance (AUC after cross-validation: 0.81, 95%CI 0.72 to 0.91). However, including CDUS and FOI resulted in a better classification of patients in respect to the outcome new DU in follow-up due to significantly better reclassification performance (NRI = 62.1, p = 0.001) and discrimination improvement (IDI = 9.7, p = 0.01).

Conclusion

A new score was introduced with the aim to predict digital ulcers. If applied correctly and with the new imaging techniques proposed, all patients at risk of digital ulcers throughout 12 months could be identified.

Efficacy and Safety of Mirikizumab in a Randomized Phase 2 Study of Patients With Ulcerative Colitis

BACKGROUND & AIMS

Interleukin 23 contributes to the pathogenesis of ulcerative colitis (UC). We investigated the effects of mirikizumab, a monoclonal antibody against the p19 subunit of interleukin 23, in a phase 2 study of patients with UC.

METHODS

We performed a trial of the efficacy and safety of mirikizumab in patients with moderate to severely active UC, enrolling patients from 14 countries from January 2016 through September 2017. Patients were randomly assigned to groups given intravenous placebo (N = 63), mirikizumab 50 mg (N = 63) or 200 mg (N = 62) with exposure-based dosing, or mirikizumab 600 mg with fixed dosing (N = 61) at weeks 0, 4, and 8. Of assigned patients, 63% had prior exposure to a biologic agent. Clinical responders (decrease in 9-point Mayo score, including ≥2 points and ≥35% from baseline with either a decrease of rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1) at week 12 who had received mirikizumab were randomly assigned to groups that received maintenance treatment with mirikizumab 200 mg subcutaneously every 4 weeks (N = 47) or every 12 weeks (N = 46). The primary endpoint was clinical remission (Mayo subscores of 0 for rectal bleeding, with 1-point decrease from baseline for stool frequency, and 0 or 1 for endoscopy) at week 12. A multiple testing procedure was used that began with the 600-mg dose group, and any nonsignificant comparison result ended the formal statistical testing procedure.

RESULTS

At week 12, 15.9% (P = .066), 22.6% (P = .004), and 11.5% (P = .142) of patients in the 50-mg, 200-mg, and 600-mg groups achieved clinical remission, respectively, compared with 4.8% of patients given placebo. The primary endpoint was not significant (comparison to 600 mg, P > .05). Clinical responses occurred in 41.3% (P = .014), 59.7% (P < .001), and 49.2% (P = .001) of patients in the 50-mg, 200-mg, and 600-mg groups, respectively, compared with 20.6% of patients given placebo. At week 52, 46.8% of patients given subcutaneous mirikizumab 200 mg every 4 weeks and 37.0% given subcutaneous mirikizumab 200 mg every 12 weeks were in clinical remission.

CONCLUSIONS

In a randomized trial of patients with UC, mirikizumab was effective in inducing a clinical response after 12 weeks. Additional studies are required to determine the optimal dose for induction of remission. Mirikizumab showed durable efficacy throughout the maintenance period. Clinicaltrials.gov, Number NCT02589665.

Association between baseline clinical and imaging findings and the development of digital ulcers in patients with systemic sclerosis

Objective

Systemic sclerosis (SSc) can lead to ischemic complications such as digital ulcers (DUs). The aim of the study was to find predictors of DUs by clinical and new imaging methods.

Patients and methods

All 79 SSc patients included in the study received a clinical, colour Doppler ultrasound (CDUS), fluorescence optical imaging (FOI) and capillaroscopy examination at baseline, and their capacity to predict new DU development was analysed in 76 patients at 12 months follow-up.

Results

Twenty-two of 76 patients (28.9%) developed new ulcers during follow-up (diffuse SSc 48.1%; limited SSc 18.4%). Receiver operating characteristic (ROC) curve analysis revealed an area under the curve of 0.7576 for DU development, with a specificity of 87% and a sensitivity of 54.6% (p = 0.0003, OR = 8.1 [95%CI 2.5–25.6]) at a cut-off of ≥ 21 points (ACR/EULAR classification criteria for SSc). Capillaroscopy and CDUS had high sensitivity (100% and 95.5%) but low specificity (28.9% and 22.2%) for ulcer occurrence when used alone, but better specificity (46.3%) when combined (OR = 18.1 [95%CI 2.3–144.4]; p = 0.0004). Using FOI, fingers with pathologic staining had a higher risk for new ulcer development in the same finger (p = 0.0153). General future DU (i.e. DU also in other fingers) was associated with a missing FOI signal in the right digit III at baseline (p = 0.048).

Conclusion

New imaging modalities can predict digital ulcer development in SSc patients with high sensitivity for capillaroscopy and CDUS and enhanced specificity when combined. A missing signal of FOI in the right digit III at baseline was associated with general future DU.

Effects of low-dose intraoperative fentanyl on postoperative respiratory complication rate: a pre-specified, retrospective analysis

BACKGROUND

Fentanyl is one of the most frequently administered intraoperative drugs and may increase the risk of postoperative respiratory complications (PRCs).

METHODS

We performed a pre-specified analysis of 145 735 adult non-cardiac surgical cases under general anaesthesia. Using multivariable logistic regression, we evaluated the association of intraoperative fentanyl dose and PRCs within 3 days after surgery (defined as reintubation, respiratory failure, pneumonia, pulmonary oedema, or atelectasis). We examined effect modification by patient characteristics, surgical site, and anaesthetics used.

RESULTS

PRCs within 3 days after surgery occurred in 18 839 (12.9%) patients. In comparison with high intraoperative fentanyl doses [median: 3.85; inter-quartile range (IQR): 3.42-4.50 μg kg^-1, quartile 4 (Q4)], low intraoperative fentanyl dose [median: 0.80, IQR: 0.00-1.14 μg kg^-1, quartile 1 (Q1)] was significantly associated with lower odds of PRCs [Q1 vs Q4: 10.9% vs 16.2%; adjusted odds ratio (aOR) 0.79; 95% confidence intervals (CI) 0.75-0.84; P<0.001; adjusted absolute risk difference (aARD) -1.7%]. This effect was augmented by thoracic surgery (P for interaction <0.001; aARD -6.2%), high doses of inhalation anaesthetics (P for interaction=0.016; aARD -2.2%) and neuromuscular blocking agents (NMBAs) (P for interaction=0.001; aARD -3.4%). Exploratory analysis demonstrated that compared with no fentanyl, low-dose fentanyl was associated with lower rates of PRCs (decile 2 vs decile 1: aOR 0.82, CI 0.75-0.89, P<0.001).

CONCLUSIONS

Intraoperative low-dose fentanyl (about 60-120 μg for a 70 kg patient) was associated with lower risk of postoperative respiratory complications compared with both no fentanyl and high-dose fentanyl. Beneficial effects of low-dose fentanyl were magnified in specific patient subgroups.

CLINICAL TRIAL REGISTRATION

NCT03198208.

Measurement of Excitation Spectra in the ^{12}C(p,d) Reaction near the η^{'} Emission Threshold

Excitation spectra of ^{11}C are measured in the ^{12}C(p,d) reaction near the η^{'} emission threshold. A proton beam extracted from the synchrotron SIS-18 at GSI with an incident energy of 2.5 GeV impinges on a carbon target. The momenta of deuterons emitted at 0° are precisely measured with the fragment separator (FRS) operated as a spectrometer. In contrast to theoretical predictions on the possible existence of deeply bound η^{'}-mesic states in carbon nuclei, no distinct structures are observed associated with the formation of bound states. The spectra are analyzed to set stringent constraints on the formation cross section and on the hitherto barely known η^{'}-nucleus interaction.

Equilibrium Adsorption of Two-Component Organic Solutes from Aqueous Solutions on Activated Carbon

The adsorption equilibria of the mixtures phenol-indol, indol- p-nitrophenol ( pNP), α-picoline-phenol from aqueous solution on activated carbon, mainly Hydraffin 71 and BHT 023/82 have been studied. Significant displacement of one solute by the other was observed. The designation of the more strongly adsorbed component depends on the relative concentration of the two solutes in the mixture and on the pH. Predictive equations for calculating mixture equilibria solely on the basis of single solute isotherms do not agree well with the experimental values; the introduction of empirical parameters determined by curve-fitting is necessary. A multi-Redlich-Peterson equation is derived, which yields a satisfactory representation of most of the present binary solute adsorption data.

CYP-mediated drug-drug interactions with evacetrapib, an investigational CETP inhibitor: in vitro prediction and clinical outcome

AIMS

Evacetrapib is a cholesteryl ester transfer protein (CETP) inhibitor under development for reducing cardiovascular events in patients with high risk vascular disease. CETP inhibitors are likely to be utilized as 'add-on' therapy to statins in patients receiving concomitant medications, so the potential for evacetrapib to cause clinically important drug-drug interactions (DDIs) with cytochromes P450 (CYP) was evaluated.

METHODS

The DDI potential of evacetrapib was investigated in vitro, followed by predictions to determine clinical relevance. Potential DDIs with possible clinical implications were then investigated in the clinic.

RESULTS

In vitro, evacetrapib inhibited all of the major CYPs, with inhibition constants (K(i)) ranging from 0.57 µM (CYP2C9) to 7.6 µM (CYP2C19). Evacetrapib was a time-dependent inhibitor and inducer of CYP3A. The effects of evacetrapib on CYP3A and CYP2C9 were assessed in a phase 1 study using midazolam and tolbutamide as probe substrates, respectively. After 14 days of daily dosing with evacetrapib (100 or 300 mg), midazolam exposures (AUC) changed by factors (95% CI) of 1.19 (1.06, 1.33) and 1.44 (1.28, 1.62), respectively. Tolbutamide exposures (AUC) changed by factors of 0.85 (0.77, 0.94) and 1.06 (0.95, 1.18), respectively. In a phase 2 study, evacetrapib 100 mg had minimal impact on AUC of co-administered simvastatin vs. simvastatin alone with a ratio of 1.25 (1.03, 1.53) at steady-state, with no differences in reported hepatic or muscular adverse events.

CONCLUSIONS

Taken together, the extent of CYP-mediated DDI with the potential clinical dose of evacetrapib is weak and clinically important DDIs are not expected to occur in patients taking concomitant medications.

Atomic origin of 3d(9)4 f(1) configuration in La(3+) solids

We have studied the excited electronic structure of LaBr3(Ce) scintillator by soft x-ray spectroscopy such as x-ray absorption spectroscopy (XAS) and x-ray emission spectroscopy (XES). The La 3d XAS and XES spectra of LaBr3(Ce) are compared with those of other La(3+) solids (LaF3, La2O3, and La metal). From this comparison, it turns out that the La 3d XAS and XES spectra from all the La(3+) solids considered here appear at almost the same energy, even though the corresponding binding energies of the 3d core holes determined by XPS (x-ray photoelectron spectroscopy) are very different. As a result, we argue that the atomic nature of the 3d⁹4f¹ configuration created by 3d¹⁰4f⁰ → 3d⁹4f¹ x-ray absorption process in La(3+) solids is maintained via the localized 4 f (1) state, which screens the 3d core holes differently from one La(3+) solid to another.

Evacetrapib: in vitro and clinical disposition, metabolism, excretion, and assessment of drug interaction potential with strong CYP3A and CYP2C8 inhibitors

Evacetrapib is an investigational cholesteryl ester transfer protein inhibitor (CETPi) for reduction of risk of major adverse cardiovascular events in patients with high-risk vascular disease. Understanding evacetrapib disposition, metabolism, and the potential for drug-drug interactions (DDI) may help guide prescribing recommendations. In vitro, evacetrapib metabolism was investigated with a panel of human recombinant cytochromes P450 (CYP). The disposition, metabolism, and excretion of evacetrapib following a single 100-mg oral dose of (14)C-evacetrapib were determined in healthy subjects, and the pharmacokinetics of evacetrapib were evaluated in the presence of strong CYP3A or CYP2C8 inhibitors. In vitro, CYP3A was responsible for about 90% of evacetrapib's CYP-associated clearance, while CYP2C8 accounted for about 10%. In the clinical disposition study, only evacetrapib and two minor metabolites circulated in plasma. Evacetrapib metabolism was extensive. A mean of 93.1% and 2.30% of the dose was excreted in feces and urine, respectively. In clinical DDI studies, the ratios of geometric least squares means for evacetrapib with/without the CYP3A inhibitor ketoconazole were 2.37 for area under the curve (AUC)(0-∞) and 1.94 for C max. There was no significant difference in evacetrapib AUC(0-τ) or C max with/without the CYP2C8 inhibitor gemfibrozil, with ratios of 0.996 and 1.02, respectively. Although in vitro results indicated that both CYP3A and CYP2C8 metabolized evacetrapib, clinical studies confirmed that evacetrapib is primarily metabolized by CYP3A. However, given the modest increase in evacetrapib exposure and robust clinical safety profile to date, there is a low likelihood of clinically relevant DDI with concomitant use of strong CYP3A or CYP2C8 inhibitors.

Energy levels of the Ce activator relative to the YAP(Ce) scintillator host

The electronic structure of the cerium-activated yttrium aluminum perovskite [YAP(Ce)] scintillator has been studied by core level x-ray spectroscopy and first-principles calculations. X-ray absorption and emission spectra at the oxygen K-edge of YAP(Ce) and CeO2 have been measured and compared with the calculated partial density of states. With the known band gap of CeO2, the measured oxygen K-edge absorption and emission spectra are used to construct a fixed relation between the valence and conduction bands of YAP and CeO2. This allows us to determine the fundamental band gap of YAP to be 8.1 ± 0.3 eV. A comparison between the cerium M4,5-edges x-ray absorption spectra of the YAP(Ce) and Ce model compounds (CeO2, CeF3, and Ce foils) then shows that the Ce activator is in the desired Ce(3+), with a small fraction of Ce(4+) due to oxidization at the surface. Finally, we determine that the ground state 4f(1) energy level of the Ce(3+) activator lies 1.8 ± 0.5 eV above the top of the valence band of the host YAP.

A Multidose Study to Examine the Effect of Food on Evacetrapib Exposure at Steady State

PURPOSE

To determine the effect of a high-fat meal on evacetrapib exposure at steady state in healthy participants.

METHODS

This was a randomized, 2-period, 2-sequence, open-label, crossover study. Patients were randomly assigned to 1 of the 2 treatment sequences in which they received evacetrapib 130 mg/d for 10 days following a 10-hour fast each day or following a high-fat breakfast each day. Plasma samples collected through 24 hours were analyzed for evacetrapib concentrations and pharmacokinetic parameter estimates including area under the concentration-time curve during a dosing interval (AUCτ), maximum observed concentration (Cmax), and time of Cmax (tmax) were calculated. Pharmacodynamic parameters, including cholesteryl ester transfer protein (CETP) activity, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides, were also assessed.

RESULTS

A total of 34 males and 6 females, mean age 41.5 years and mean body mass index 26.6 kg/m(2), were enrolled. Statistical analysis showed AUCτ was 44% higher (90% confidence interval [CI]: 29%-62%) and Cmax was 51% higher (90% CI: 28%-79%) in the fed state than in the fasted state, indicating an effect of food. Consistent with higher evacetrapib exposure, changes in HDL-C, LDL-C, and CETP activity appeared to be greater in the fed state than in the fasted state. There were no notable changes in total cholesterol or triglycerides following administration in the fed and fasted states. The 130-mg doses of evacetrapib were well tolerated with and without food.

CONCLUSION

A high-fat meal increased evacetrapib mean exposure at steady state by 44% in healthy participants.

Assessment of the persistence of anacetrapib and evacetrapib concentrations using two pharmacokinetic modeling approaches

Anacetrapib, a cholesterol ester transfer protein (CETP) inhibitor, has been reported to have longer elimination half-life after longer treatment. Two pharmacokinetic model-based approaches were used to assess whether evacetrapib, another CETP inhibitor, could behave similarly. Using population pharmacokinetic (PopPK) modeling, evacetrapib and anacetrapib pharmacokinetics were characterized using available concentration-time data, and steady-state conditions were simulated. Published 2-compartment models for each compound were adapted to include a hypothetical third compartment representing a depot into which drug could partition. Physiologically based pharmacokinetic (PBPK) modeling was used to predict steady-state conditions and terminal half-life based on known physicochemical and dispositional properties. The PopPK model described the anacetrapib data well, showing a likely third compartment with estimated apparent volume of 40,700 L. Anacetrapib's estimated half-life for this compartment was 550 days. Simulations for evacetrapib using a hypothetical 3-compartment model, the third compartment being consistent with that of the anacetrapib model, produced predictions inconsistent with reported results, indicating that evacetrapib did not substantially accumulate into a large compartment. The PBPK simulations were consistent with PopPK results, predicting accumulation for anacetrapib (but not evacetrapib) followed by very slow elimination. Based on available data and known physicochemical properties, evacetrapib is not expected to accumulate substantially during long-term treatment.

The impact of age on the benefits and risks of aliskiren treatment: analyses of the 3A registry

We aimed to analyze benefits and risks of aliskiren treatment in older adults (⩾ 65 years) in clinical practice. Patients (n = 14,986) were assigned to either aliskiren (ALIS), an angiotensin-converting-enzyme inhibitor or angiotensin receptor blocker (ACEi/ARB), or an agent not blocking the renin-angiotensin system (non-RAS). Older adults (n = 7396) had a longer history of hypertension (8.7 vs 4.7 years; P < 0.0001), lower mean diastolic blood pressure (DBP; 87.7 ± 11.0 vs 92.1 ± 11.0 mm Hg) and more renal (12.0 vs 5.6%; P < 0.0001) or cardiovascular disease (44.0 vs 18.9%; P < 0.0001); 4548 received aliskiren (68.8%), 1215 ACEi/ARBs (18.4%) and 850 non-RAS treatments (12.9%). Office BP at 1 year was reduced by 18.4 ± 21.5/7.2 ± 12.0 mm Hg. BP reductions were greater (19.5 ± 21.7/7.6 ± 12.1 mm Hg) in the aliskiren group than in the ACEi/ARB (15.6 ± 20.9/6.4 ± 11.9) and non-RAS groups (16.1 ± 20.7/6.5 ± 11.7 mm Hg), respectively (P<0.0001 for systolic BP (SBP) and <0.01 for DBP). After multivariable adjustment, differences in SBP reductions were clinically irrelevant and no differences were noted for DBP. Adverse effects were higher in older adults with no differences between treatment groups. In conclusion, the present analysis of a large, unselected cohort of patients in clinical practice from the 3A study, offers real-life evidence of the effectiveness and safety of aliskiren for the treatment of hypertension in older adults.

Circadian rhythm and day to day variability of serum potassium concentration: a pilot study

BACKGROUND

Hyperkalemia is a common and life-threatening complication frequently seen in patients with acute kidney injury, end-stage renal disease and chronic heart failure. Cardiac arrest and ventricular fibrillation are possible consequences. Biosensors are currently being developed to measure serum potassium under ambulatory conditions and trigger an alarm if the potassium concentration exceeds normal limits. Only few studies exist on the circadian rhythm of potassium; and its dependence on age and kidney function is less clear.

METHODS

Our observational monocentric exploratory study included 30 subjects of which 15 had impaired renal function (RF) (GFR <60 ml/min/1.73 m(2)). Subjects were further categorized into three age groups: 18-39 years (N normal RF = 5, N impaired RF = 4), 40-59 years (N normal RF = 5, N impaired RF = 6), 60-80 years (N normal RF = 5, N impaired RF = 5). Serum potassium levels were measured every 2 h during a 24 h period and repeated once after 2, 4, or 6 days.

RESULTS

In the 15 subjects with normal RF, the lowest mean potassium level (3.96 ± 0.14 mmol/l) was observed at 9 p.m. and the greatest (4.23 ± 0.23 mmol/l) at 1 p.m. In patients with impaired RF the lowest mean potassium level (4.20 ± 0.32 mmol/l) was observed at 9 p.m. and the highest (4.57 ± 0.46 mmol/l) at 3 p.m. The range between the mean of minimum and maximum was greater in patients with impaired RF (0.71 ± 0.45 mmol/l) than in subjects with normal RF (0.53 ± 0.14 mmol/l) [p < 0.001]. No difference in the circadian rhythm was found between the first and second examination.

CONCLUSION

Our results indicate that patients with normal and impaired RF have comparable circadian patterns of serum potassium concentrations, but higher fluctuations in patients with impaired RF. These results have clinical relevance for developing an automatic biosensor to measure the potassium concentration in blood under ambulatory conditions in patients at high risk for potassium fluctuations.

Effects of the cholesteryl ester transfer protein inhibitor evacetrapib on lipoproteins, apolipoproteins and 24-h ambulatory blood pressure in healthy adults

Objectives

We investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of evacetrapib.

Methods

Healthy volunteers received multiple daily doses of evacetrapib (10–600 mg) administered for up to 15 days in a placebo-controlled study.

Key findings

Mean peak plasma concentrations of evacetrapib occurred at 4–6 h and terminal half-life ranged 24–44 h. Steady state was achieved at approximately 10 days; all subjects had undetectable levels of evacetrapib 3 weeks after their last dose. The trough inhibition of cholesteryl ester transfer protein (CETP) activity was 65 and 84% at 100 and 300 mg, respectively. At the highest dose (600 mg), evacetrapib significantly inhibited CETP activity (91%), increased HDL-C (87%) and apo AI (42%), and decreased LDL-C (29%) and apo B (26%) relative to placebo. For the highest dose tested, levels of evacetrapib, CETP activity, CETP mass, HDL-C and LDL-C returned to levels at or near baseline after a 2-week washout period. Evacetrapib at the highest dose tested did not produce any significant effect on 24-h ambulatory systolic or diastolic blood pressure.

Conclusions

Multiple doses of evacetrapib potently inhibited CETP activity, leading to substantial elevations in HDL-C and lowering of LDL-C. Evacetrapib was devoid of clinically relevant effects on blood pressure and mineralocorticoid levels.

The pharmacokinetics and pharmacokinetic/pharmacodynamic relationships of evacetrapib administered as monotherapy or in combination with statins

Evacetrapib is a novel cholesteryl ester transfer protein (CETP) inhibitor currently being evaluated in a late-stage cardiovascular outcome trial. Using population-based models, we analyzed evacetrapib concentration data along with high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) data from a 12-week study in dyslipidemic patients treated with evacetrapib alone or in combination with atorvastatin, simvastatin, or rosuvastatin. Evacetrapib pharmacokinetics were characterized using a two-compartment model with first-order absorption. Evacetrapib exposure increased in a less than dose-proportional manner, similar to other CETP inhibitors. No patient factors had a clinically relevant impact on evacetrapib pharmacokinetics. The relationships between evacetrapib exposure and HDL-C and LDL-C were characterized using E_max models. The theoretical maximal mean HDL-C increase and LDL-C decrease relative to baseline were 177 and 44.1%, respectively. HDL-C change from baseline was found to be negatively correlated with baseline HDL-C. A pharmacologically independent LDL-C reduction was found when evacetrapib was coadministered with statins.

Evacetrapib at a Supratherapeutic Steady State Concentration Does Not Prolong QT in a Thorough QT/QTc Study in Healthy Participants

Purpose:

To evaluate whether evacetrapib prolongs QT intervals in healthy participants.

Methods:

This was a single-center, randomized, active and placebo-controlled, 3-period, 6-sequence, and crossover study. Participants were randomized to 1 of 6 treatment sequences in which they received 1 of 3 treatments: evacetrapib 1200 mg daily for 10 days (supratherapeutic dose), moxifloxacin 400 mg for 1 day (positive control), or placebo for 10 days in each of the 3 separate treatment periods. Electrocardiographic parameters were recorded at time points specified in the protocol. The primary end point was the comparison of evacetrapib effect on the population-corrected QT interval (QTcP) to that of placebo at 7 time points following dosing on day 10. An upper limit of the 2-sided 90% confidence interval (CI) <10 milliseconds confirmed the absence of significant effect. Pharmacokinetic parameters were also calculated.

Results:

Subjects were predominantly male (73.2%) with a mean age of 43.1 years and a mean body mass index of 25.9 kg/m2. For the primary analysis, the upper bound of the 2-sided 90% CI for the mean difference between evacetrapib and placebo was <10 milliseconds at all time points on day 10. Following administration of moxifloxacin, the QTcP increased by ≥5 milliseconds at all time points (2, 3, and 4 hours postdose). Maximum plasma concentrations of evacetrapib occurred at a median time of approximately 2 hours, and the mean apparent elimination half-life was approximately 41 hours. The area under the curve and Cmax achieved in this study were both ∼5-fold the values that are expected with the dose level being studied in a phase 3 cardiovascular outcome study. A 1200-mg supratherapeutic dose of evacetrapib was considered to be well tolerated after 10 days of daily dosing in healthy participants.

Conclusions:

Evacetrapib is not associated with QT interval prolongation, even at supratherapeutic doses.

Systemic treatment with 4-211Atphenylalanine enhances survival of rats with intracranial glioblastoma

OBJECTIVE

Increased amino acid transport in brain tumours is used for diagnostic purposes. It has been shown that the α-emitting radionuclide astatine-211 labeled to L-phenylalanine is taken up by glioblastoma cells. We here tested, if systemic treatment with 4-[211At]astatine-phenylalanine (At-Phe) has a beneficial effect on survival of rats with intracranial glioblastoma.

ANIMALS, METHODS

The rat glioblastoma cell line BT4Ca was implanted into the prefrontal cortex of female BDIX rats by stereotaxic microinjection (10,000 cells/3 µl; n = 83). 3 days after implantation At-Phe or phosphate buffered saline were injected intravenously. A third group was treated twice, i.e., on day 3 and 10. Health condition was assessed each day by using a score system. Rats were sacrificed on days 6, 10, 13 and 17 after implantation, or when showing premortal health condition to measure tumour volume and necrosis. The proliferation index (PI) was assessed after immunohistochemical staining of Ki-67.

RESULTS

Survival time of rats treated twice with At-Phe was significantly prolonged. Additionally, both At-Phe-treated groups remained significantly longer in a better health condition. Rats with poor health status had larger tumours than rats with fair health condition. Overall, irrespective of treatment the PI was reduced in rats with poor health condition. Necrosis was larger in rats treated twice with At-Phe.

CONCLUSION

Intravenous treatment with At-Phe enhanced survival time of rats with intracranial glioblastomas and improved health condition. These results encourage studies using local treatment of intracranial glioblastoma with At-Phe, either by repeated local injection or by intracavital application after tumour resection.

Measurement of the T + T neutron spectrum using the national ignition facility

Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100 </~ keV. To describe the spectrum, we have developed an R-matrix model that accounts for interferences from fermion symmetry and intermediate states, and show these effects to be non-negligible. We also find the spectrum can be described by sequential decay through ℓ=1 states in (5)He, which differs from previous interpretations.

Charged-particle spectroscopy for diagnosing shock ρR and strength in NIF implosions

The compact Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the National Ignition Facility (NIF) as a National Ignition Campaign diagnostic. The WRF measures the spectrum of protons from D-(3)He reactions in tuning-campaign implosions containing D and (3)He gas; in this work we report on the first proton spectroscopy measurement on the NIF using WRFs. The energy downshift of the 14.7-MeV proton is directly related to the total ρR through the plasma stopping power. Additionally, the shock proton yield is measured, which is a metric of the final merged shock strength.

Neutron spectrometry--an essential tool for diagnosing implosions at the National Ignition Facility (invited)

DT neutron yield (Y(n)), ion temperature (T(i)), and down-scatter ratio (dsr) determined from measured neutron spectra are essential metrics for diagnosing the performance of inertial confinement fusion (ICF) implosions at the National Ignition Facility (NIF). A suite of neutron-time-of-flight (nTOF) spectrometers and a magnetic recoil spectrometer (MRS) have been implemented in different locations around the NIF target chamber, providing good implosion coverage and the complementarity required for reliable measurements of Y(n), T(i), and dsr. From the measured dsr value, an areal density (ρR) is determined through the relationship ρR(tot) (g∕cm(2)) = (20.4 ± 0.6) × dsr(10-12 MeV). The proportionality constant is determined considering implosion geometry, neutron attenuation, and energy range used for the dsr measurement. To ensure high accuracy in the measurements, a series of commissioning experiments using exploding pushers have been used for in situ calibration of the as-built spectrometers, which are now performing to the required accuracy. Recent data obtained with the MRS and nTOFs indicate that the implosion performance of cryogenically layered DT implosions, characterized by the experimental ignition threshold factor (ITFx), which is a function of dsr (or fuel ρR) and Y(n), has improved almost two orders of magnitude since the first shot in September, 2010.

Assembly of high-areal-density deuterium-tritium fuel from indirectly driven cryogenic implosions

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).