When to Start a Statin Is a Preference-Sensitive Decision

Pharmacokinetics, pharmacodynamics, and safety of frunexian in healthy Chinese volunteer adults: A randomized dose-escalation phase I study

The purpose of this study was to evaluate the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of frunexian (formerly known as EP-7041 and HSK36273) injection, a small molecule inhibitor of activated coagulation factor XI (FXIa), in healthy Chinese adult volunteers. This study was a randomized, placebo- and positive-controlled, sequential, ascending-dose (0.3/0.6/1.0/1.5/2.25 mg/kg/h) study of 5-day continuous intravenous infusions of frunexian. Frunexian administration exhibited an acceptable safety profile with no bleeding events. Steady state was rapidly reached with a median time ranging from 1.02 to 1.50 h. The mean half-life ranged from 1.15 to 1.43 h. Frunexian plasma concentration at a steady state and area under the concentration-time curve exhibited dose-proportional increases. The dose-escalation study of frunexian demonstrated its progressively enhanced capacities to prolong activated partial thromboplastin time (aPTT) and inhibit FXIa activity. The correlations between PK and PD biomarkers (aPTT/baseline and FXI clotting activity/baseline) were described by the two Emax models, with the EC50 values of 8940 and 1300 ng/mL, respectively. Frunexian exhibits good safety and PK/PD properties, suggesting it is a promising candidate for anticoagulant drug.

Factor XI/XIa inhibitors for the prevention and treatment of venous and arterial thromboembolism: A narrative review

During the past decade, direct oral anticoagulants (DOACs) have advanced and simplified the prevention and treatment of venous thromboembolism (VTE). However, there remains a high incidence of bleeds, which calls for agents that have a reduced risk of bleeding. Factor XI (FXI) deficiency is associated with lower rates of venous thrombosis and stroke compared to the general population with a lower risk of bleeding. In conjunction with this, phase 2 studies have demonstrated safety and the potential for reduced thrombotic events with FXI inhibitors as compared to currently available medications. The aim of this review is to summarize key data on the clinical pharmacology of FXI, the latest developments in clinical trials of FXI inhibitors, and to describe the efficacy and safety profiles of FXI inhibitors for the prevention of venous and arterial thromboembolism.

First-In-Human Study to Assess the Safety, Pharmacokinetics, and Pharmacodynamics of SHR2285, a Small-Molecule Factor XIa Inhibitor in Healthy Subjects

Background: Targeting factor XI (FXI) is a promising therapeutic strategy for the treatment and prevention of thrombosis without increasing the risk of bleeding. Here, we assessed the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of SHR2285, a novel FXIa inhibitor, in healthy subjects.

Methods: In this randomized, double-blinded, placebo-controlled, dose-ascending single-dosing trial (NCT03769831), eligible volunteer subjects receive either SHR2285 or placebo in a 3:1 ratio. Subjects assigned to the SHR2285 group received a single oral dose of SHR2285 at 50 mg, which was subsequently escalated to 100 mg, 200 mg, and 400 mg. Safety, pharmacokinetics, and pharmacodynamics parameters were assessed. All subjects were followed for 6 days.

Results: SHR2285 was well tolerated. All adverse events were grade 1, and there was no evidence of bleeding events. The PK results revealed a rapid onset of action of SHR2285 (median time to maximum plasma concentration [Tmax] in different dose groups ranged 3.0–4.0 h) and the mean half-life ranged from 7.6 to 15.8 h. The metabolite SHR164471 had a slightly longer Tmax than the parent SHR2285, reaching a peak at a median of 6.0–7.0 h, and its mean half-life were 10.1–14.7 h in different dose groups. The sums of the area under the concentration–time curve from zero to time infinity of SHR2285 and SHR164471 in the 200 and 400 mg groups were similar, indicating the sum pharmacological activity of SHR2285 and SHR164471 showed a saturation trend between 200 and 400 mg. PD analysis showed that the inhibition of FXI activity was synchronized with prolonged activated partial thromboplastin time after SHR2285 administration, but the serum prothrombin time and international normalized ratio levels were not affected by SHR2285.

Conclusion: SHR2285 demonstrated favorable safety, PK, and PD profiles in the dose range of 50 mg–400 mg. This first-in-human study supports the further development of SHR2285 for indications requiring anticoagulation.

Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03769831, identifier [NCT03769831].

The Need for Brevity During Shared Decision Making (SDM) for Cancer Screening: Veterans' Perspectives on an "Everyday SDM" Compromise

Introduction. Detailed or “full” shared decision making (SDM) about cancer screening is difficult in the primary care setting. Time spent discussing cancer screening is time not spent on other important issues. Given time constraints, brief SDM that is incomplete but addresses key elements may be feasible and acceptable. However, little is known about how patients feel about abbreviated SDM. This study assessed patient perspectives on a compromise solution (“everyday SDM”): 1) primary care provided makes a tailored recommendation, 2) briefly presents qualitative information on key tradeoffs, and 3) conveys full support for decisional autonomy and desires for more information. Methods. We recruited a stratified random sample of Veterans from an academic Veterans Affairs medical center who were eligible for lung cancer screening, oversampling women and minority patients, to attend a 6-hour deliberative focus group. Experts informed participants about cancer screening, factors that influence screening benefits, and the role of patient preferences. Then, facilitator-led small groups elicited patient questions and informed opinions about the everyday SDM proposal, its acceptability, and their recommendations for improvement. Results. Thirty-six Veterans with a heavy smoking history participated (50% male, 83% white). There was a strong consensus that everyday SDM was acceptable if patients were the final deciders and could get more information on request. Participants broadly recommended that clinicians only mention downsides directly related to screening and avoid discussion of potential downstream harms (such as biopsies). Discussion. Although further testing in more diverse populations and different conditions is needed, these patients found the everyday SDM approach to be acceptable for routine lung cancer screening discussions, despite its use of an explicit recommendation and presentation of only qualitative information.

Drugs in phase I and II clinical development for the prevention of stroke in patients with atrial fibrillation

INTRODUCTION

Atrial fibrillation is the most frequently diagnosed cardiac arrhythmia globally and is associated with ischemic stroke and heart failure. Patients with atrial fibrillation are typically prescribed long-term anticoagulants in the form of either vitamin K antagonists or non-vitamin K antagonist oral anticoagulants; however, both carry a potential risk of adverse bleeding.

AREAS COVERED

This paper sheds light on emerging anticoagulant agents which target clotting factors XI and XII, or their activated forms - XIa and XIIa, respectively, within the intrinsic coagulation pathway. The authors examined data available on PubMed, Scopus, and the clinical trials registry of the United States National Library of Medicine (www.clinicaltrials.gov).

EXPERT OPINION

Therapies targeting factors XI or XII can yield anticoagulant efficacy with the potential to reduce adverse bleeding. Advantages for targeting factor XI or XII include a wider therapeutic window and reduced bleeding. Long-term follow-up studies and a greater understanding of the safety and efficacy are required. Atrial fibrillation is a chronic disease and therefore the development of oral formulations is key.

Guideline Concordance of Statin Treatment Decisions: A Retrospective Cohort Study

Guidelines recommend initiation of statins depending on cardiovascular risk and low-density lipoprotein cholesterol (LDL-C) levels. In this retrospective cohort study, we aimed to assess guideline concordance of statin treatment decisions and to find determinants of undertreatment in Swiss primary care in the period 2016–2019. We drew on electronic medical records of 8060 statin-naive patients (50.0% female, median age 59 years) with available LDL-C levels and cardiovascular risk. Guideline concordance was assessed based on the recommendations of the European Society of Cardiology, and multilevel logistic regression was performed to find determinants of undertreatment. We found that statin treatment was initiated in 10.2% of patients during one year of follow up. Treatment decisions were classified as guideline-concordant in 63.0%, as undertreatment in 35.8% and as overtreatment in 1.2%. Among determinants of undertreatment were small deviation from LDL-C treatment thresholds (odds ratio per decrease by 1 mmol/L: 2.09 [95% confidence interval 1.87–2.35]), high compared with very high cardiovascular risk (1.64 [1.30–2.05]), female sex (1.31 [1.05–1.64]), and being treated by older general practitioners (per 10 year decrease: 0.74 [0.61–0.90]). In conclusion, undertreatment of patients at high or very high cardiovascular risk was common, but general practitioners considered cardiovascular risk and LDL-C in their treatment decisions.

Discovery of Benzyl Tetraphosphonate Derivative as Inhibitor of Human Factor Xia

The inhibition of factor XIa (FXIa) is a trending paradigm for the development of new generations of anticoagulants without a substantial risk of bleeding. In this report, we present the discovery of a benzyl tetra-phosphonate derivative as a potent and selective inhibitor of human FXIa. Biochemical screening of four phosphonate/phosphate derivatives has led to the identification of the molecule that inhibited human FXIa with an IC50 value of ∼7.4 μM and a submaximal efficacy of ∼68 %. The inhibitor was at least 14-fold more selective to FXIa over thrombin, factor IXa, factor Xa, and factor XIIIa. It also inhibited FXIa-mediated activation of factor IX and prolonged the activated partial thromboplastin time of human plasma. In Michaelis-Menten kinetics experiment, inhibitor 1 reduced the VMAX of FXIa hydrolysis of a chromogenic substrate without significantly affecting its KM suggesting an allosteric mechanism of inhibition. The inhibitor also disrupted the formation of FXIa - antithrombin complex and inhibited thrombin-mediated and factor XIIa-mediated formation of FXIa from its zymogen factor XI. Inhibitor 1 has been proposed to bind to or near the heparin/polyphosphate-binding site in the catalytic domain of FXIa. Overall, inhibitor 1 is the first benzyl tetraphosphonate small molecule that allosterically inhibits human FXIa, blocks its physiological function, and prevents its zymogen activation by other clotting factors under in vitro conditions. Thus, we put forward benzyl tetra-phosphonate 1 as a novel lead inhibitor of human FXIa to guide future efforts in the development of allosteric anticoagulants.

Factor XI(a) inhibitors for thrombosis: an updated patent review (2016-present)

Introduction: Anticoagulation without bleeding is an ideal goal in treating thrombosis, however, this goal has not been achieved. All current anticoagulants are associated with significant bleeding which limits their safe use. Genetic and pharmacological findings indicate that factor XIa is a key player in thrombosis, yet it is a relatively marginal one in hemostasis. Thus, factor XIa and its zymogen offer a unique opportunity to develop anticoagulants with low bleeding risk.Areas covered: A survey of patent literature has retrieved more than 50 patents on the discovery of novel therapeutics targeting factor XI(a) since 2016. Small molecules, monoclonal antibodies, oligonucleotides, and polypeptides have been developed to inhibit factor XI(a). Many inhibitors are in early development and few have been evaluated in clinical trials.Expert opinion: Factor XI(a) is being actively pursued as a drug target for the development of effective and safer anticoagulants. Although many patents claiming factor XI(a) inhibitors were filed prior to 2016, recent literature reveals a moderately declining trend. Nevertheless, more agents have entered different levels of clinical trials. These agents exploit diverse mechanistic strategies for inhibition. Although further development is warranted, reaching one or more of these agents to the clinic will transform the anticoagulation therapy.

Prediction and management of CAD risk based on genetic stratification

Discovery of genetic risk variants for CAD and their assembly on a computerized microarray enables a genetic risk score (GRS) to be expressed as a single number. Utilizing this array, genetic risk stratification has been performed in over 1 million cases and controls. The genetic score based on one's DNA can be determined anytime from birth on and is independent of age and conventional risk factors. Utilizing the GRS, one can select those at highest risk and would benefit most from primary prevention. Clinical trials have shown that modifying lifestyle or using statin therapy reduces the risk for CAD by approximately 50%. The use of the GRS for primary prevention will have a transformative effect on preventing the spread of CAD.

Practice variation among Dutch paediatricians in palivizumab prescription rates: the importance of parental counselling approach

AIM

To investigate differences in palivizumab prescription rates between Dutch paediatricians, and the role of parent counselling in this practice variation.

METHODS

A retrospective chart review of premature infants <32 weeks of gestation, aged less than six months at the start of the winter season, born between January 2012 and July 2014, in three secondary hospital-based paediatric practices in the Netherlands.

RESULTS

We included 208 patients, 133 (64%) of whom received palivizumab. Prescription rates varied considerably between the three hospitals: 8% (6/64), 89% (32/36) and 99% (97/98). A noticeable difference in the way parents were counselled about palivizumab was the use of the number needed to treat (NNT). In the hospital with the lowest prescription rate (8%), an NNT of 20 to prevent one hospitalisation was explicitly discussed with parents. Bronchiolitis-related hospital admissions occurred in 11.3% of patients receiving palivizumab compared to 20.0% in nonimmunised infants (p = 0.086).

CONCLUSION

Considerable practice variation exists among Dutch paediatricians regarding palivizumab prescription rates. The counselling method seems to play an important role. Presenting palivizumab prophylaxis as a preference-sensitive decision, combined with the explicit use and explanation of an NNT, leads many parents to refrain from respiratory syncytial virus immunisation.

Genetic stratification for primary prevention of coronary artery disease

PURPOSE OF REVIEW

To review the literature showing genetic risk variants is a reliable means of stratifying for risk of CAD for primary prevention.

RECENT FINDINGS

Over 90 genetic risk variants have been discovered that predispose to CAD. Results of several studies show that these risk variants effectively stratify for risk of CAD in asymptomatic individuals.

SUMMARY

The total individual genetic risk can be summarized into a single number referred to as the genetic risk score (GRS). The GRS unlike the Framingham Risk Score is not dependent on age and independent of conventional risk factors. As DNA does not change during one's lifetime the GRS can be calculated at birth or any time thereafter. Furthermore, the GRS has been shown to provide superior discriminatory power in selecting individuals who will benefit most from lifestyle changes or statin therapy. A prospective study showed individuals with high GRS and a favorable lifestyle was associated with significant reduction of cardiac events compared with an unfavorable lifestyle. Furthermore, the study shows inherited risk can be reduced analogous to reduction of risk form acquired and environmental factors. The use of GRS to stratify for risk of CAD in asymptomatic individuals could transform primary prevention worldwide.

Factor XIa Inhibitors as New Anticoagulants

With the introduction of thrombin and factor Xa inhibitors to the oral anticoagulant market, significant improvements in both efficacy and safety have been achieved. Early clinical and preclinical data suggest that inhibitors of factor XIa can provide a still safer alternative, with expanded efficacy for arterial indications. This Perspective provides an overview of target rationale and details of the discovery and development of inhibitors of factor XIa as next generation antithrombotic agents.