Pemafibrate and other triglyceride-lowering therapies to reduce risk of cardiovascular and metabolic disease

PURPOSE OF REVIEW

Although high triglycerides are consistently associated with elevated risk of cardiovascular disease (CVD), therapies that reduce triglyceride levels have inconsistently translated into reduced CVD risk.

RECENT FINDINGS

To date, three clinical trials have tested triglyceride-lowering therapies in patients with hypertriglyceridemia (HTG) and elevated risk of incident/recurrent CVD. In REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial), assignment to IPE, a highly purified eicosapentanoic acid (EPA), resulted in a 25% reduction in nonfatal myocardial infarction), nonfatal stroke, cardiovascular death, coronary revascularization and hospitalization for unstable angina. By contrast, the combination of EPA and docosahexanoic acid (DHA) carboxylic fatty acids used in the STRENGTH trial (Statin Residual Risk With Epanova in High Cardiovascular Risk Patients With Hypertriglyceridemia) failed to reduce CVD risk. Most recently, PROMINENT (Pemafibrate to Reduce Cardiovascular Outcomes by Reducing Triglycerides in Patients with Diabetes) also failed to demonstrate reduction in CVD events despite use of a potent triglyceride-lowering, fibric-acid derivative. However, improvement in HTG-associated metabolic complications (e.g. nonalcoholic fatty liver disease) was observed with pemafibrate as well as with another potent triglyceride-lowering therapy (i.e. pegozafermin). Moreover, trials are underway evaluating whether the most fatal metabolic complication of HTG, pancreatitis, may be reduced with highly potent triglyceride-lowering therapies (e.g. apolipoprotein C3 inhibitors).

SUMMARY

Taken together, HTG is associated with increased risk of CVD and attendant adverse metabolic sequalae. To this end, a potentially promising and evidence-based landscape is emerging for treating a clinical phenotype that in the past has been insufficiently addressed.

Poppers maculopathy missed in a patient with cataract highlights the importance of preoperative optical coherence tomography

Poppers maculopathy is a complication of alkyl nitrate (poppers) inhalation. It presents with non-specific symptoms and variable signs, which can make it difficult to diagnose. We present a case of coexisting cataract and poppers maculopathy in a patient. He had vague visual symptoms that were attributed entirely to his cataract and he went on to have cataract surgery. Suboptimal postoperative visual acuity and normal clinical examination triggered further investigation with spectral-domain optical coherence tomography (SD-OCT), after which poppers maculopathy was diagnosed. We highlight the importance of performing OCT in the preoperative assessment of a cataract patient, especially where the cataract is mild and may not fully account for symptoms. The patient showed complete visual recovery on drug cessation despite ongoing maculopathy on OCT scans.

Enhanced liver fibrosis (ELF) score predicts hepatic decompensation and mortality

Background & Aims

In community pathways for detection of liver disease the most common reason for referral is fibrosis assessment. We investigated the impact of adding the Enhanced Liver Fibrosis (ELF) score as a second-line test (subsequent to an indeterminate or high Fibrosis-4 index [FIB-4] and/or non-alcoholic fatty liver disease fibrosis score) to guide referral and prognostication in our multi-aetiology pathway.

Methods

Patients with ELF results from the intelligent Liver Function Testing (iLFT) pathway were recruited. Case note review was undertaken to compare ELF with endpoints of cirrhosis, hepatic decompensation, and mortality (liver-related and all-cause death).

Results

In total, 1,327 individuals were included with a median follow-up of 859 days and median ELF score of 10.2. Overall sensitivity for cirrhosis at the 9.8 threshold was 94% (100% for metabolic-associated steatotic liver disease, 89% for alcohol-related liver disease). Determination of the ELF score as a second-line test reduced the referral rate by 34%. ELF scores predicted hepatic outcomes; each unit change was associated with increased decompensation (adjusted Hazard Ratio [aHR] 2.215, 95% CI: 1.934-2.537) and liver-related mortality (aHR 2.024, 95% CI: 1.674-2.446). ELF outperformed FIB-4 for risk of liver-related mortality, particularly in the short-term (area under the curve [AUC] 94.3% vs. 82.8% at six months). Where FIB-4 was indeterminate, ELF had higher AUC for all outcomes within at least 2 years. ELF ≥13 was associated with particularly high rates of decompensation (26% within 90 days) and all-cause mortality (38% at 1 year).

Conclusions

The addition of ELF reduced the number of individuals referred for fibrosis assessment following iLFT pathway testing and provided useful prognostic information. Individuals with ELF scores ≥13 were considered at high-risk of negative outcomes warranting urgent clinical assessment.

Impact and implications

Primary care pathways for suspected liver disease are increasingly common and often lead to increased specialist hepatology referrals for fibrosis assessment. This study, using clinical follow-up for liver-related outcomes, provides further evidence supporting ELF testing to safely reduce referrals in a two-step approach when combined with other simple fibrosis markers. Additionally, ELF scores predict liver-related morbidity and mortality, with ELF scores ≥13 indicating particularly high-risk patients. This study may help inform the implementation of diagnostic pathways for early detection of liver disease and highlights the need for urgent review of individuals with very high ELF scores.

Giant electron-mediated phononic nonlinearity in semiconductor-piezoelectric heterostructures

Efficient and deterministic nonlinear phononic interactions could revolutionize classical and quantum information processing at radio frequencies in much the same way that nonlinear photonic interactions have at optical frequencies. Here we show that in the important class of phononic materials that are piezoelectric, deterministic nonlinear phononic interactions can be enhanced by orders of magnitude via the heterogeneous integration of high-mobility semiconductor materials. To this end, a lithium niobate and indium gallium arsenide heterostructure is utilized to produce the most efficient three- and four-wave phononic mixing to date, to the best of our knowledge. We then show that the conversion efficiency can be further enhanced by applying semiconductor bias fields that amplify the phonons. We present a theoretical model that accurately predicts the three-wave mixing efficiencies in this work and extrapolate that these nonlinearities can be enhanced far beyond what is demonstrated here by confining phonons to smaller dimensions in waveguides and optimizing the semiconductor material properties.

Oesophageal cell collection device and biomarker testing to identify high-risk Barrett's patients requiring endoscopic investigation

BACKGROUND

Barrett's oesophagus surveillance places significant burden on endoscopy services yet is vital to detect early cancerous change. Oesophageal cell collection device (OCCD) testing was introduced across Scotland for Barrett's surveillance in response to the COVID-19 pandemic. This national pragmatic retrospective study presents the CytoSCOT programme results and evaluates whether OCCD testing is successfully identifying high-risk Barrett's patients requiring urgent endoscopy.

METHODS

All patients undergoing OCCD testing for Barrett's surveillance across 11 Scottish health boards over a 32-month period were identified. Patients who underwent endoscopy within 12 months of OCCD test were included. Individual patient records were interrogated to record clinical information and OCCD test result to categorize patients into risk groups. Endoscopic histopathology results were analysed according to risk group and segment length. Patients were deemed high risk if the OCCD test demonstrated atypia and/or p53 positivity.

RESULTS

4204 OCCD tests were performed in 3745 patients: 608 patients underwent endoscopy within 12 months and were included in this analysis. Patients with longer Barrett's segments were significantly more likely to have an abnormal OCCD test. 50/608 patients (8.2%) had high-grade dysplasia or cancer on endoscopic biopsies: this equates to 1.3% of the total group (50/3745). 46/50 patients (92.0%) were deemed high risk, triggering urgent endoscopy: this rose to 100% with insufficient tests removed. There were no cancers diagnosed within 12 months post-OCCD in the low-risk group.

CONCLUSION

OCCD testing is an effective triage tool to identify high-risk patients with Barrett's oesophagus requiring further investigation with endoscopy within the real-world setting.

Effect of preoperative biliary drainage on intraoperative biliary cultures and surgical outcomes after pancreatic resection

BACKGROUND

Prolonged obstructive jaundice (OJ), associated with resectable pancreatic pathology, has many deleterious effects that are potentially rectifiable by preoperative biliary drainage (POBD) at the cost of increased postoperative infective complications. The aim of this study is to assess the impact of POBD on intraoperative biliary cultures (IBCs) and surgical outcomes in patients undergoing pancreatic resection.

METHODS

Data from patients at Groote Schuur Hospital, Cape Town, between October 2008 and May 2019 were analysed. Demographic, clinical, and outcome variables were evaluated, including perioperative morbidity, mortality, and 5-year survival.

RESULTS

Among 128 patients, 69.5% underwent POBD. The overall perioperative mortality in this study was 8.8%. The POBD group had a significantly lower perioperative mortality rate compared to the non-drainage group (5.6% vs. 25.6%). POBD patients had a higher incidence of surgical site infections (55.1% vs. 23.1%), polymicrobial growth from IBCs and were more likely to culture resistant organisms. Five-year survival was similar in the two groups.

CONCLUSION

POBD was associated with a high incidence of resistant organisms on the IBCs, a high incidence of surgical site infections and a high correlation between cultures from the surgical site infection and the IBCs.

The incidence of dermatitis following application of foam tape in healthy volunteers-A prospective trial

BACKGROUND

Foam tape is commonly used in the emergency department as a dressing over chest tubes owing to its occlusive and compressible properties. There is a paucity of data regarding the incidence of significant cutaneous reactions to this material. We conducted a prospective trial to evaluate the incidence of dermatitis following application of foam tape to the upper arm of a cohort of healthy volunteers.

METHODS

This was a prospective, interventional trial. We enrolled a cohort of consenting, healthy physicians, nurses, and ancillary staff at a teaching facility who did not have known hypersensitivity to foam tape. Study investigators applied a 2 × 2 inch piece of 3 M microfoam adhesive to the medial aspect of each subject's upper arm. The contralateral arm served as a reference for comparison. The adhesive remained in place for 48 h and the study authors assessed patients utilizing the previously validated Cutaneous Irritancy Scoring System (CISS). Categorical variables analyzed by chi-square, continuous variables with t-tests.

RESULTS

There were 40 subjects in the study group; 52% female, mean age 40±7 years, 55% non-White race. 10/40 (25%; 95%CI[14%, 41%]) of subjects had erythema; 9/40 (22%) had an erythema score of 1 and 1/40 (2.5%) had a score of 2. With respect to edema, 2/40 (5%; 95% CI[1%,18%]); 1/40(2.5%) had an edema score of 1, and 1/40(2.5%) had a score of 2. There were 9/40 subjects with an irritancy score > 0; (22%; 95%CI[12%,38%]); 7/40(18%) had an irritancy score of 1, and 2/4(5.0%) had a score of 2. In terms of the severity score, 10/40 (25%; 95%CI[14%, 41%]) had a score > 0; 9/40(22%) had a score of 1, and 1/40(2.5%) had a score of 2. Overall, 10/40 (25%; 95%CI[14%, 41%]) of subjects had at least one positive measure of a reaction of any kind. Subjects' age, gender and race were not found to be statistically significantly associated with the incidence of erythema, edema, or irritancy. In addition, these characteristics were not statistically significantly associated with severity score > 0. The p values for all the above bivariate analyses were > 0.05.

CONCLUSIONS

Cutaneous reactions occurred in 25% of healthy volunteers after the application of foam tape to the arm. Patient characteristics were not associated with risk of a skin reaction.

CLINICAL TRIALS REGISTRATION

#NCT06059417.

National adoption of an esophageal cell collection device for Barrett's esophagus surveillance: impact on delay to investigation and pathological findings

High quality Barrett's esophagus surveillance is crucial to detect early neoplastic changes. An esophageal cell collection device (OCCD) was introduced as a triage tool for Barrett's surveillance. This study aims to evaluate whether the Scottish OCCD program (CytoSCOT) has reduced delays to Barrett's surveillance, and whether delayed surveillance negatively impacts endoscopic pathology. All patients undergoing OCCD testing for Barrett's surveillance across 11 Scottish health boards between 14/9/2020 and 13/9/2022 were identified. Patients were dichotomised into two groups (Year 1 vs. Year 2), with individual records interrogated to record demographics, recommended surveillance interval, time from last endoscopy to OCCD test, and OCCD result. Patients were deemed high-risk if the OCCD demonstrated atypia and/or p53 positivity. Further analysis was performed on patients who underwent endoscopy within 12 months of OCCD testing. A total of 3223 OCCD tests were included in the analysis (1478 in Year 1; 1745 in Year 2). In Year 1 versus Year 2, there was a longer median delay to surveillance (9 vs. 5 months; P < 0.001), increased proportion of patients with delayed surveillance (72.6% vs. 57.0%; P < 0.001), and more high-risk patients (12.0% vs. 5.3%; P < 0.001). 425/3223 patients (13.2%) were further investigated with upper gastrointestinal endoscopy, 57.9% of which were high-risk. As surveillance delay increased beyond 24 months, high-risk patients were significantly more likely to develop dysplasia or malignancy (P = 0.004). Delayed Barrett's esophagus surveillance beyond 24 months is associated with increased risk of pre-cancerous pathology. The CytoSCOT program has reduced delays in surveillance, promoting earlier detection of dysplasia and reducing burden on endoscopy services.

Effectiveness of BNT162b2 COVID-19 primary series vaccination in children aged 5-17 years in the United States: a cohort study

BACKGROUND

COVID-19 vaccines are authorized for use in children in the United States; real-world assessment of vaccine effectiveness in children is needed. This study's objective was to estimate the effectiveness of receiving a complete primary series of monovalent BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine in US children.

METHODS

This cohort study identified children aged 5-17 years vaccinated with BNT162b2 matched with unvaccinated children. Participants and BNT162b2 vaccinations were identified in Optum and CVS Health insurance administrative claims databases linked with Immunization Information System (IIS) COVID-19 vaccination records from 16 US jurisdictions between December 11, 2020, and May 31, 2022 (end date varied by database and IIS). Vaccinated children were followed from their first BNT162b2 dose and matched to unvaccinated children on calendar date, US county of residence, and demographic and clinical factors. Censoring occurred if vaccinated children failed to receive a timely dose 2 or if unvaccinated children received any dose. Two COVID-19 outcome definitions were evaluated: COVID-19 diagnosis in any medical setting and COVID-19 diagnosis in hospitals/emergency departments (EDs). Propensity score-weighted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with Cox proportional hazards models, and vaccine effectiveness (VE) was estimated as 1 minus HR. VE was estimated overall, within age subgroups, and within variant-specific eras. Sensitivity, negative control, and quantitative bias analyses evaluated various potential biases.

RESULTS

There were 453,655 eligible vaccinated children one-to-one matched to unvaccinated comparators (mean age 12 years; 50% female). COVID-19 hospitalizations/ED visits were rare in children, regardless of vaccination status (Optum, 41.2 per 10,000 person-years; CVS Health, 44.1 per 10,000 person-years). Overall, vaccination was associated with reduced incidence of any medically diagnosed COVID-19 (meta-analyzed VE = 38% [95% CI, 36-40%]) and hospital/ED-diagnosed COVID-19 (meta-analyzed VE = 61% [95% CI, 56-65%]). VE estimates were lowest among children 5-11 years and during the Omicron-variant era.

CONCLUSIONS

Receipt of a complete BNT162b2 vaccine primary series was associated with overall reduced medically diagnosed COVID-19 and hospital/ED-diagnosed COVID-19 in children; observed VE estimates differed by age group and variant era.

REGISTRATION

The study protocol was publicly posted on the BEST Initiative website ( https://bestinitiative.org/wp-content/uploads/2022/03/C19-VX-Effectiveness-Protocol_2022_508.pdf ).

Lipoprotein(a) Blood Levels and Cardiovascular Risk Reduction With Icosapent Ethyl

BACKGROUND

Elevated lipoprotein(a) (Lp[a]) concentrations are associated with increased cardiovascular event risk even in the presence of well-controlled low-density lipoprotein cholesterol levels, but few treatments are documented to reduce this residual risk.

OBJECTIVES

The aim of this post hoc analysis of REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) was to explore the cardiovascular benefit of icosapent ethyl (IPE) across a range of Lp(a) levels.

METHODS

A total of 8,179 participants receiving statin therapy with established cardiovascular disease or age ≥50 years with diabetes and ≥1 additional risk factor, fasting triglyceride 1.69 to 5.63 mmol/L, and low-density lipoprotein cholesterol 1.06 to 2.59 mmol/L were randomized to receive 2 g twice daily of IPE or matching placebo. Relationships between continuous baseline Lp(a) mass concentration and risk for first and total (first and subsequent) major adverse cardiovascular events (MACE) were analyzed, along with the effects of IPE on first MACE among those with Lp(a) concentrations ≥50 or <50 mg/dL.

RESULTS

Among 7,026 participants (86% of those randomized) with baseline Lp(a) assessments, the median concentration was 11.6 mg/dL (Q1-Q3: 5.0-37.4 mg/dL). Lp(a) had significant relationships with first and total MACE (P < 0.0001), while event reductions with IPE did not vary across the range of Lp(a) (interaction P > 0.10). IPE significantly reduced first MACE in subgroups with concentrations ≥50 and <50 mg/dL.

CONCLUSIONS

Baseline Lp(a) concentration was prognostic for MACE among participants with elevated triglyceride levels receiving statin therapy. Importantly, IPE consistently reduced MACE across a range of Lp(a) levels, including among those with clinically relevant elevations.

Next Generation Neuropeptide Y Receptor Small Molecule Agonists Inhibit Mosquito Biting Behavior

Female Aedes aegypti mosquitoes can spread disease-causing pathogens when they bite humans to obtain blood nutrients required for egg production. Following a complete blood meal, host-seeking is suppressed until eggs are laid. Neuropeptide Y-like Receptor 7 (NPYLR7) plays a role in endogenous host-seeking suppression and previous work identified small molecule NPYLR7 agonists that suppress host-seeking and blood feeding when fed to mosquitoes at high micromolar doses. Using structure activity relationship analysis and structure-guided design we synthesized 128 compounds with similarity to known NPYLR7 agonists. Although in vitro potency (EC50) was not strictly predictive of in vivo effect, we identified 3 compounds that suppressed blood feeding from a live host when fed to mosquitoes at a 1 μM dose, a 100-fold improvement over the original reference compound. Exogenous activation of NPYLR7 represents an innovative vector control strategy to block mosquito biting behavior and prevent mosquito/human host interactions that lead to pathogen transmission.

A location-based anatomic classification system for acute pancreatic fluid collections: Roadmap for optimal intervention in the step-up era

Walled-off pancreatic necrosis (WOPN) is a local complication of acute necrotizing pancreatitis frequently requiring intervention. Treatment is typically through the coordinated efforts of a multidisciplinary team. Current management guidelines recommend a step-up approach beginning with minimally invasive techniques (percutaneous or transmural endoscopic drainage) followed by escalation to more invasive procedures if needed. Although the step-up approach is an evidence-based treatment paradigm for management of pancreatic fluid collections, it lacks guidance regarding optimal invasive technique selection based on the anatomic characteristics of pancreatic fluid collections. Similarly, existing cross-sectional imaging-based classification systems of pancreatic fluid collections have been used to predict disease severity and prognosis; however, none of these systems are designed to guide intervention. We propose a novel classification system which incorporates anatomic characteristics of pancreatic fluid collections (location and presence of disconnected pancreatic duct) to guide intervention selection and clinical decision making. We believe adoption of this simple classification system will help streamline treatment algorithms and facilitate cross-study comparisons for pancreatic fluid collections.

Incursion of Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Virus, Brazil, 2023

We report 4 highly pathogenic avian influenza A(H5N1) clade 2.3.4.4.b viruses in samples collected during June 2023 from Royal terns and Cabot's terns in Brazil. Phylodynamic analysis revealed viral movement from Peru to Brazil, indicating a concerning spread of this clade along the Atlantic Americas migratory bird flyway.

Association of Lipoprotein (a) with peri-coronary inflammation in persons with and without HIV infection

BACKGROUND

Persons with HIV (PWH) have an increased risk of developing cardiovascular disease (CVD) compared to persons without HIV (PWoH). Lipoprotein a (Lp(a)) is a known atherosclerotic risk factor in PWoH, but there are no studies investigating Lp(a) and peri-coronary inflammation.

OBJECTIVE

To investigate whether Lp(a) is associated with peri-coronary inflammation as assessed by the fat attenuation index (FAI) and activated monocytes and T lymphocytes in PWH and PWoH.

METHODS

We measured plasma levels of Lp(a) at study entry in 58 PWH and 21 PWoH without CVD and who had FAI measurements. Associations of Lp(a) with FAI values of the right coronary artery (RCA) and left anterior descending artery (LAD) were evaluated using multivariable regression models adjusted for potential confounders. Correlations between Lp(a) levels and systemic inflammatory markers and immune cell subsets were examined.

RESULTS

Lp(a) was associated with greater peri-coronary inflammation among PWH compared to PWoH (β=1.73, P=0.019) in the RCA, in adjusted models. Significant correlations were observed with certain inflammatory markers (TNFR-I, b=0.295, P<0.001; TNFR-II, b=0.270, P=0.002; hs-CRP, b=0.195, P=0.028). Significant correlations were found between Lp(a) levels and several markers of monocyte activation: CD16 -CD163+ (b= -0.199, P=0.024), and CD16 -DR+ MFI (b= -0.179, P=0.042) and T cell subset CD38+CD4+ TEMRA (b= 0.177, P= 0.044).

CONCLUSIONS

Lp(a) was associated with greater peri-coronary inflammation in the RCA in PWH compared to PWoH, as well as with select systemic inflammatory markers and specific subsets of immune cells in peripheral circulation.

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.

Immune evasion by proteolytic shedding of natural killer group 2, member D ligands in Helicobacter pylori infection

Background

Helicobacter pylori (H. pylori) uses various strategies that attenuate mucosal immunity to ensure its persistence in the stomach. We recently found evidence that H. pylori might modulate the natural killer group 2, member 2 (NKG2D) system. The NKG2D receptor and its ligands are a major activation system of natural killer and cytotoxic T cells, which are important for mucosal immunity and tumor immunosurveillance. The NKG2D system allows recognition and elimination of infected and transformed cells, however viruses and cancers often subvert its activation. Here we aimed to identify a potential evasion of the NKG2D system in H. pylori infection.

Methods

We analyzed expression of NKG2D system genes in gastric tissues of H. pylori gastritis and gastric cancer patients, and performed cell-culture based infection experiments using H. pylori isogenic mutants and epithelial and NK cell lines.

Results

In biopsies of H. pylori gastritis patients, NKG2D receptor expression was reduced while NKG2D ligands accumulated in the lamina propria, suggesting NKG2D evasion. In vitro, H. pylori induced the transcription and proteolytic shedding of NKG2D ligands in stomach epithelial cells, and these effects were associated with specific H. pylori virulence factors. The H. pylori-driven release of soluble NKG2D ligands reduced the immunogenic visibility of infected cells and attenuated the cytotoxic activity of effector immune cells, specifically the anti-tumor activity of NK cells.

Conclusion

H. pylori manipulates the NKG2D system. This so far unrecognized strategy of immune evasion by H. pylori could potentially facilitate chronic bacterial persistence and might also promote stomach cancer development by allowing transformed cells to escape immune recognition and grow unimpeded to overt malignancy.

Using a Function-First "Scout Fragment"-Based Approach to Develop Allosteric Covalent Inhibitors of Conformationally Dynamic Helicase Mechanoenzymes

Helicases, classified into six superfamilies, are mechanoenzymes that utilize energy derived from ATP hydrolysis to remodel DNA and RNA substrates. These enzymes have key roles in diverse cellular processes, such as translation, ribosome assembly, and genome maintenance. Helicases with essential functions in certain cancer cells have been identified, and helicases expressed by many viruses are required for their pathogenicity. Therefore, helicases are important targets for chemical probes and therapeutics. However, it has been very challenging to develop chemical inhibitors for helicases, enzymes with high conformational dynamics. We envisioned that electrophilic "scout fragments", which have been used in chemical proteomic studies, could be leveraged to develop covalent inhibitors of helicases. We adopted a function-first approach, combining enzymatic assays with enantiomeric probe pairs and mass spectrometry, to develop a covalent inhibitor that selectively targets an allosteric site in SARS-CoV-2 nsp13, a superfamily-1 helicase. Further, we demonstrate that scout fragments inhibit the activity of two human superfamily-2 helicases, BLM and WRN, involved in genome maintenance. Together, our findings suggest an approach to discover covalent inhibitor starting points and druggable allosteric sites in conformationally dynamic mechanoenzymes.

Cost-Effectiveness of Icosapent Ethyl in REDUCE-IT USA: Results From Patients Randomized in the United States

BACKGROUND

In 3146 REDUCE-IT USA (Reduction of Cardiovascular Events With Icosapent Ethyl Intervention Trial USA) participants, icosapent ethyl (IPE) reduced first and total cardiovascular events by 31% and 36%, respectively, over 4.9 years of follow-up.

METHODS AND RESULTS

We used participant-level data from REDUCE-IT USA, 2021 US costs, and IPE costs ranging from $4.59 to $11.48 per day, allowing us to examine a range of possible medication costs. The in-trial analysis was participant-level, whereas the lifetime analysis used a Markov model. Both analyses considered value from a US health sector perspective. The incremental cost-effectiveness ratio (incremental costs divided by incremental quality-adjusted life-years) of IPE compared with standard care (SC) was the primary outcome measure. There was incremental gain in quality-adjusted life-years with IPE compared with SC using in-trial (3.28 versus 3.13) and lifetime (10.36 versus 9.83) horizons. Using an IPE cost of $4.59 per day, health care costs were lower with IPE compared with SC for both in-trial ($29 420 versus $30 947) and lifetime ($216 243 versus $219 212) analyses. IPE versus SC was a dominant strategy in trial and over the lifetime, with 99.7% lifetime probability of an incremental cost-effectiveness ratio <$50 000 per quality-adjusted life-year gained. At a medication cost of $11.48 per day, the cost per quality-adjusted life-year gained was $36 208 in trial and $9582 over the lifetime.

CONCLUSIONS

In this analysis, at $4.59 per day, IPE offers better outcomes than SC at lower costs in trial and over a lifetime and is cost-effective at $11.48 per day for conventional willingness-to-pay thresholds. Treatment with IPE should be strongly considered in US patients like those enrolled in REDUCE-IT USA.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.

Effectiveness of monovalent COVID-19 booster/additional vaccine doses in the United States

Background

Monovalent booster/additional doses of COVID-19 vaccines were first authorized in August 2021 in the United States. We evaluated the real-world effectiveness of receipt of a monovalent booster/additional dose of COVID-19 vaccine compared with receiving a primary vaccine series without a booster/additional dose.

Methods

Cohorts of individuals receiving a COVID-19 booster/additional dose after receipt of a complete primary vaccine series were identified in 2 administrative insurance claims databases (Optum, CVS Health) supplemented with state immunization information system data between August 2021 and March 2022. Individuals with a complete primary series but without a booster/additional dose were one-to-one matched to boosted individuals on calendar date, geography, and clinical factors. COVID-19 diagnoses were identified in any medical setting, or specifically in hospitals/emergency departments (EDs). Propensity score-weighted hazards ratios (HRs) and 95% confidence intervals (CI) were estimated with Cox proportional hazards models; vaccine effectiveness (VE) was estimated as 1 minus the HR by vaccine brand overall and within subgroups of variant-specific eras, immunocompromised status, and homologous/heterologous booster status.

Results

Across both data sources, we identified 752,165 matched pairs for BNT162b2, 410,501 for mRNA-1273, and 11,398 for JNJ-7836735. For any medically diagnosed COVID-19, meta-analyzed VE estimates for BNT162b2, mRNA-1273, and JNJ-7836735, respectively, were: BNT162b2, 54% (95% CI, 53%-56%); mRNA-1273, 58% (95% CI, 56%-59%); JNJ-7836735, 34% (95% CI, 23%-44%). For hospital/ED-diagnosed COVID-19, VE estimates ranged from 70% to 76%. VE was generally lower during the Omicron era than the Delta era and for immunocompromised individuals. There was little difference observed by homologous or heterologous booster status.

Conclusion

The original, monovalent booster/additional doses were reasonably effective in real-world use among the populations for which they were indicated during the study period. Additional studies may be informative in the future as new variants emerge and new vaccines become available.Registration: The study protocol was publicly posted on the BEST Initiative website (https://bestinitiative.org/wp-content/uploads/2022/03/C19-VX-Effectiveness-Protocol_2022_508.pdf).

Single-cell analysis of chromatin accessibility in the adult mouse brain

Recent advances in single-cell technologies have led to the discovery of thousands of brain cell types; however, our understanding of the gene regulatory programs in these cell types is far from complete1-4. Here we report a comprehensive atlas of candidate cis-regulatory DNA elements (cCREs) in the adult mouse brain, generated by analysing chromatin accessibility in 2.3 million individual brain cells from 117 anatomical dissections. The atlas includes approximately 1 million cCREs and their chromatin accessibility across 1,482 distinct brain cell populations, adding over 446,000 cCREs to the most recent such annotation in the mouse genome. The mouse brain cCREs are moderately conserved in the human brain. The mouse-specific cCREs-specifically, those identified from a subset of cortical excitatory neurons-are strongly enriched for transposable elements, suggesting a potential role for transposable elements in the emergence of new regulatory programs and neuronal diversity. Finally, we infer the gene regulatory networks in over 260 subclasses of mouse brain cells and develop deep-learning models to predict the activities of gene regulatory elements in different brain cell types from the DNA sequence alone. Our results provide a resource for the analysis of cell-type-specific gene regulation programs in both mouse and human brains.