Indobufen or Aspirin on Top of Clopidogrel After Coronary Drug-Eluting Stent Implantation (OPTION): A Randomized, Open-Label, End Point-Blinded, Noninferiority Trial

The pharmacology of antiplatelet agents for primary, secondary, and tertiary prevention of ischemic stroke

INTRODUCTION

Ischemic etiology accounts for two thirds of all strokes in which platelet activation and aggregation play a major role. A variety of antiplatelet therapies have been tested for primary, secondary, and tertiary prevention, with certain patient subtypes benefiting more than others from a specific regimen.

AREAS COVERED

This review aims at synthetizing current evidence on pharmacology of antiplatelet agents approved for primary, secondary, and tertiary stroke prevention and their application among possible patient subtypes that may benefit more from their administration.

EXPERT OPINION

Management of ischemic stroke has largely evolved over the past decades. A better understanding of stroke pathophysiology has allowed to identify patients who can benefit most from antiplatelet therapies, with varying degrees of benefit depending on whether these agents are being used for primary, secondary, or tertiary prevention. Importantly, the antiplatelet treatment regimens currently available have expanded and no longer limited to aspirin but include other drugs such as P2Y12 and phosphodiesterase inhibitors, also used in combination, as well as precision medicine approaches using genetic testing aiming at optimizing the safety and efficacy in this population.

Real-world performance of indobufen versus aspirin after percutaneous coronary intervention: insights from the ASPIRATION registry

BACKGROUND

Indobufen is widely used in patients with aspirin intolerance in East Asia. The OPTION trial launched by our cardiac center examined the performance of indobufen based dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). However, the vast majority of patients with acute coronary syndrome (ACS) and aspirin intolerance were excluded. We aimed to explore this question in a real-world population.

METHODS

Patients enrolled in the ASPIRATION registry were grouped according to the DAPT strategy that they received after PCI. The primary endpoints were major adverse cardiovascular and cerebrovascular events (MACCE) and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding. Propensity score matching (PSM) was adopted for confounder adjustment.

RESULTS

A total of 7135 patients were reviewed. After one-year follow-up, the indobufen group was associated with the same risk of MACCE versus the aspirin group after PSM (6.5% vs. 6.5%, hazard ratio [HR] = 0.99, 95% confidence interval [CI] = 0.65 to 1.52, P = 0.978). However, BARC type 2, 3, or 5 bleeding was significantly reduced (3.0% vs. 11.9%, HR = 0.24, 95% CI = 0.15 to 0.40, P < 0.001). These results were generally consistent across different subgroups including aspirin intolerance, except that indobufen appeared to increase the risk of MACCE in patients with ACS.

CONCLUSIONS

Indobufen shared the same risk of MACCE but a lower risk of bleeding after PCI versus aspirin from a real-world perspective. Due to the observational nature of the current analysis, future studies are still warranted to further evaluate the efficacy of indobufen based DAPT, especially in patients with ACS.

TRIAL REGISTRATION

Chinese Clinical Trial Register ( https://www.chictr.org.cn ); Number: ChiCTR2300067274.

The effects of CYP2C19 genotype polymorphism and clopidogrel resistance on ischemic event occurrence in patients with peripheral arterial disease undergoing revascularization: A prospective cohort study

INTRODUCTION

Peripheral arterial disease (PAD) affects approximately 236 million people worldwide. Therefore, this study aimed to investigate the relationship between CYP2C19 genotype polymorphisms and clopidogrel resistance (CR) following revascularization in patients with PAD.

MATERIALS AND METHODS

In total, 345 patients who underwent PAD revascularization were monitored for five years and risk factors for ischemic events were identified. Platelet reactivity and CYP2C19 genotypes were measured, and patients were classified as normal, intermediate, or poor metabolizers based on their genotypes. The study endpoint was defined as an ischemic event, that encompassed major adverse cardiovascular or limb events, or all-cause death.

RESULTS

In this study, ischemic events following PAD revascularization were associated with patient age, prior minor amputation, the Rutherford category before revascularization, indications for revascularization, index ankle-branchial index before revascularization, CYP2C19 phenotypes, and CR. Intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients after PAD revascularization. Similarly, intermediate and poor metabolism, the Rutherford category before revascularization, and CR were independent risk factors for ischemic events in patients with PAD after revascularization within five years. Intermediate and poor metabolizers had a higher platelet reactivity and risk of CR than normal metabolizers. However, poor metabolizers had a higher platelet reactivity and risk of CR than intermediate metabolizers. Furthermore, the hazard ratio for ischemic events increased with platelet reactivity. This effect was more prevalent in intermediate and poor metabolizers than in normal metabolizers.

CONCLUSIONS

Ischemic events in patients after PAD revascularization were affected by independent risk factors. Decreased clopidogrel metabolism increased the platelet reactivity and CR in patients after PAD revascularization. Furthermore, high platelet reactivity was associated with an increased risk of ischemic events in patients with intermediate and poor metabolism.

Clopidogrel with indobufen or aspirin in minor ischemic stroke or high-risk transient ischemic attack: a randomized controlled clinical study

BACKGROUND

Ischemic stroke and transient ischemic attack (TIA) are the most prevalent cerebrovascular diseases. The conventional antiplatelet drugs are associated with an inherent bleeding risk, while indobufen is a new antiplatelet drug and has the similar mechanism of antiplatelet aggregation as aspirin with more safety profile. However, there have been no studies evaluating the combination therapy of indobufen and clopidogrel for antiplatelet therapy in cerebrovascular diseases.

OBJECTIVE

The CARMIA study aims to investigate the effectiveness and safety of a new dual antiplatelet therapy consisting of indobufen and clopidogrel comparing with the conventional dual antiplatelet therapy consisting of aspirin and clopidogrel in patients with minor ischemic stroke or high-risk TIA.

METHODS

An open-label randomized controlled clinical trial was conducted at a clinical center. We randomly assigned patients who had experienced a minor stroke or transient ischemic attack (TIA) within 72 h of onset, or within 1 month if they had intracranial stenosis (IS), to receive either indobufen 100 mg twice daily or aspirin 100 mg once daily for 21 days. For patients with IS, the treatment duration was extended to 3 months. All patients received a loading dose of 300 mg clopidogrel orally on the first day, followed by 75 mg once daily from the second day to 1 year. We collected prospective data using paper-based case report forms, and followed up on enrolled patients was conducted to assess the incidence of recurrent ischemic stroke or TIA, mRS score, NIHSS (National Institutes of Health Stroke Scale) score, and any bleeding events occurring within 3 month after onset.

RESULTS

We enrolled 202 patients diagnosed with ischemic stroke or transient ischemic attack. After applying the criteria, 182 patients were eligible for data analysis. Endpoint events (recurrence of ischemic stroke/TIA, myocardial infarction, or death) were observed in 6 patients (6.5%) receiving aspirin and clopidogrel, including 4 (4.3%) with stroke recurrence, 1 (1.1%) with TIA recurrence, and 1 (1%) with death. In contrast, no endpoint events were reported in the indobufen and clopidogrel group (P = 0.029). The group of patients receiving indobufen and clopidogrel exhibited significantly lower modified Rankin Scale (mRS) score. (scores range from 0 to 6, with higher scores indicating more severe disability) compared to the aspirin and clopidogrel group (common odds ratio 3.629, 95% CI 1.874-7.036, P < 0.0001). Although the improvement rate of NIHSS score in the indobufen and clopidogrel group was higher than that in the aspirin and clopidogrel group, the difference was not statistically significant (P > 0.05). Bleeding events were observed in 8 patients (8.6%) receiving aspirin and clopidogrel, including 4 (4.3%) with skin bleeding, 2 (2.2%) with gingival bleeding, 1 (1.1%) with gastrointestinal bleeding, and 1 (1.1%) with urinary system bleeding. On the other hand, only 1 patient (1.1%) in the indobufen and clopidogrel group experienced skin bleeding (P = 0.035).

CONCLUSION

The combination of indobufen and clopidogrel has shown non-inferior and potentially superior effectiveness and safety compared to aspirin combined with clopidogrel in patients with minor ischemic stroke and high-risk TIA in the CARMIA study (registered under chictr.org.cn with registration number ChiCTR2100043087 in 01/02/2021).

Comparative efficacy of different Chinese patent medicines in preventing restenosis after percutaneous coronary intervention: a systematic review and Bayesian network meta-analysis of randomized clinical trials

Background: Chinese patent medicines (CMPs) have curative effectiveness in preventing coronary restenosis. However, the relative efficacy between different CPMs has not been sufficiently investigated. Methods: Randomized clinical trials were searched from electronic databases including PubMed, Web of Science, Cochrane Library, Embase, CNKI, VIP, WanFang, SinoMed, Chinese Clinical Trial Registry, and ClinicalTrials.gov. Bayesian network meta-analysis was performed to analyze CPMs' efficacy in preventing angiographic restenosis, recurrence angina, acute myocardial infarction, and target lesion revascularization after percutaneous coronary intervention. Results: This network meta-analysis included 47 trials with 5,077 patients evaluating 11 interventions. Regarding angiographic restenosis, the efficacy of CPMs (except Xuezhikang capsule) combined with standard treatment (Std) was superior to Std alone, and Guanxin Shutong capsule plus Std reduced the risk of angiographic restenosis by 76% (relative risk 0.24, 95% confidence interval 0.11-0.45, and very low to moderate certainty of evidence), most likely the best intervention. Fufang Danshen dripping pill combined with Std showed superiority over other interventions for relieving recurrence angina, which can reduce the risk by 83% (RR 0.17, 95% CI 0.04-0.51, very low to moderate certainty of evidence) compared to Std alone. In acute myocardial infarction after percutaneous coronary intervention, compared with Std alone, Danhong injection plus Std displayed a significant effect (RR 0.11, 95% CI 0.00-0.69, very low to moderate certainty of evidence) and was the best treatment probably. Chuanxiongqin tablet plus Std was the most effective treatment for reducing target lesion revascularization by 90% (RR 0.10, 95% CI 0.00-0.60, very low to moderate certainty of evidence) compared with Std alone. Conclusion: The results indicated that CPMs combined with Std reduced the risk of coronary restenosis after percutaneous coronary intervention. However, the results should be interpreted cautiously due to significant data limitations.

Case report: Fatal traumatic coronary artery dissection-an overlooked complication of chest fracture

Coronary artery dissection caused by trauma is a rare occurrence that can be life-threatening. Accordingly, its rapid identification and treatment are essential to improve patient outcomes. Here, we present a case of a patient who suffered multiple rib and femur fractures after falling from a height of eighteen meters and subsequently experienced persistent chest pain. After the initial diagnostic workup, the medical team diagnosed the patient's chest pain as rib fractures and failed to consider the potential of a cardiac injury as the underlying cause. No emphasis was placed on monitoring changes in myocardial enzymes and ECG, which could have indicated coronary artery dissection. The dissection was confirmed and treated with a stent only after the subsequent coronary angiography (CAG) and optical coherence tomography (OCT) examinations, gradually relieving the patient's chest pain. In this case report, we discuss the management of fractures complicated by traumatic coronary artery dissection and highlight the benefits of OCT in diagnosing and treating this condition. The case also emphasizes the importance of considering coronary artery injury in patients with chest pain due to trauma.

Reversible and Non-Competitive Inhibition of Cyclooxygenase by Indobufen for Efficient Antiplatelet Action and Relief of Gastrointestinal Irritation

Clinically, indobufen is widely used for the treatment of antiplatelet aggregation and anticoagulation. Prior studies have discovered that abnormal platelet function can be promptly restored to normal when the drug is stopped. Herein, through the study of the enzyme reaction kinetics, we demonstrated that the inhibitory effect of indobufen on cyclooxygenase-1 (COX-1) was reversible and non-competitive. Specifically, the cyclooxygenase inhibition experiment showed that the level of 6-keto-PGF1α in the gastric mucosa of the indobufen-treated groups was significantly higher than that of the aspirin group (###p < 0.001), indicating a higher level of PGI2 in and a better physiological state of the gastric mucosa. Moreover, the rat gastric ulcer index and mucosal section experiments further confirmed the relief of gastrointestinal irritation and the adverse reaction rate of the indobufen-treated group compared to those of the aspirin group. Furthermore, indobufen was verified to exert reversible inhibitory activity on the heme group of COX-1 and thus reversibly inhibit COX-1 activity. In general, compared with aspirin, the long-term oral administration of indobufen yields a lower risk of gastrointestinal symptoms, such as ulcers.

Dual Antiplatelet Therapy: A Concise Review for Clinicians

Dual antiplatelet therapy (DAPT) combines two antiplatelet agents to decrease the risk of thrombotic complications associated with atherosclerotic cardiovascular diseases. Emerging data about the duration of DAPT is being published continuously. New approaches are trying to balance the time, benefits, and risks for patients taking DAPT for established cardiovascular diseases. Short-term dual DAPT of 3-6 months, or even 1 month in high-bleeding risk patients, is equivalent in terms of efficacy and effectiveness compared to long-term DAPT for patients who experienced percutaneous coronary intervention in an acute coronary syndrome setting. Prolonged DAPT beyond 12 months reduces stent thrombosis, major adverse cardiovascular events, and myocardial infarction rates but increases bleeding risk. Extended DAPT does not significantly benefit stable coronary artery disease patients in reducing stroke, myocardial infarction, or cardiovascular death. Ticagrelor and aspirin reduce cardiovascular events in stable coronary artery disease with diabetes but carry a higher bleeding risk. Antiplatelet therapy duration in atrial fibrillation patients after percutaneous coronary intervention depends on individual characteristics and bleeding risk. Antiplatelet therapy is crucial for post-coronary artery bypass graft and transcatheter aortic valve implantation; Aspirin (ASA) monotherapy is preferred. Antiplatelet therapy duration in peripheral artery disease depends on the scenario. Adding vorapaxar and cilostazol may benefit secondary prevention and claudication, respectively. Carotid artery disease patients with transient ischemic attack or stroke benefit from antiplatelet therapy and combining ASA and clopidogrel is more effective than ASA alone. The optimal duration of DAPT after carotid artery stenting is uncertain. Resistance to ASA and clopidogrel poses an incremental risk of deleterious cardiovascular events and stroke. The selection and duration of antiplatelet therapy in patients with cardiovascular disease requires careful consideration of both efficacy and safety outcomes. The use of combination therapies may provide added benefits but should be weighed against the risk of bleeding. Further research and clinical trials are needed to optimize antiplatelet treatment in different patient populations and clinical scenarios.

Indobufen versus aspirin in patients with acute ischaemic stroke in China (INSURE): a randomised, double-blind, double-dummy, active control, non-inferiority trial

BACKGROUND

Aspirin is recommended for secondary stroke prevention in patients with moderate-to-severe ischaemic stroke but can lead to gastrointestinal intolerance and bleeding. Indobufen is used as an alternative antiplatelet agent in some countries, despite an absence of large-scale clinical trials for this indication. We tested the hypothesis that indobufen is non-inferior to aspirin in reducing the risk of new stroke at 90 days in patients with moderate-to-severe ischaemic stroke.

METHODS

We conducted a randomised, double-blind, double-dummy, active control, non-inferiority trial at 163 tertiary and district general hospitals in China. Eligible participants were aged 18-80 years with acute moderate-to-severe ischaemic stroke (National Institutes of Health Stroke Scale score 4-18). We randomly assigned (1:1) participants within 72 h of the onset of symptoms to receive either indobufen (100 mg tablet twice per day) or aspirin (100 mg tablet once per day) for 90 days. The randomisation sequence was computer generated centrally and stratified by local participating centres. Masked local investigators assigned the random code to patients in ascending order and provided a treatment kit corresponding to the random code. The primary efficacy outcome was new stroke and the primary safety outcome was severe or moderate bleeding, both within 90 days. This primary efficacy outcome was assessed in all randomly assigned and consenting patients and in a per-protocol group (ie, all patients finishing the treatment without major violation of the trial protocol). Safety analyses were done in the safety-analysis population (ie, all patients who received at least one dose of the study drug and had a safety assessment available). We assessed the non-inferiority of indobufen versus aspirin using the one-sided upper limit of the 95% CI of the hazard ratio (HR) with a prespecified non-inferiority margin of 1·25. This trial is registered with ClinicalTrials.gov (NCT03871517).

FINDINGS

This trial took place between June 2, 2019, and Nov 28, 2021. Of 84 093 patients screened, 5438 patients were randomly assigned to receive either indobufen (n=2715) or aspirin (n=2723), all of whom were included in the primary analyses. Median age was 64·2 years (IQR 56·1-70·6); 1921 (35·3%) were women and 3517 (64·7%) were men. Stroke occurred within 90 days in 213 (7·9%) patients in the indobufen group versus 175 (6·4%) in the aspirin group (HR 1·23, 95% CI 1·01-1·50; pnon-inferiority=0·44). Moderate or severe bleeding occurred in 18 (0·7%) patients in the indobufen group and in 28 (1·0%) in the aspirin group (0·63, 95% CI 0·35 to 1·15; p=0·13). Adverse events within 90 days occurred in 666 (24·5%) patients in the indobufen group and 679 (24·9%) patients in the aspirin group (p=0·73).

INTERPRETATION

In patients with acute moderate-to-severe ischaemic stroke, indobufen was not non-inferior to aspirin because the upper limit of the 95% CI was greater than 1·25. Furthermore, indobufen seemed to be inferior to aspirin in reducing the risk of recurrent stroke at 90 days because the lower limit of the 95% CI was greater than 1·00. Although moderate or severe bleeding did not differ between groups, these findings do not support the use of indobufen for secondary stroke prevention in patients with moderate-to-severe ischaemic stroke.

FUNDING

Hangzhou Zhongmei Huadong Pharmaceutical and Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Advances in Clinical Cardiology 2022: A Summary of Key Clinical Trials

INTRODUCTION

Over the course of 2022, numerous key clinical trials with valuable contributions to clinical cardiology were published or presented at major international conferences. This review seeks to summarise these trials and to reflect on their clinical context.

METHODS

The authors reviewed clinical trials presented at major cardiology conferences during 2022, including the American College of Cardiology (ACC), European Association for Percutaneous Cardiovascular Interventions (EuroPCR), European Society of Cardiology (ESC), Transcatheter Cardiovascular Therapeutics (TCT), American Heart Association (AHA), European Heart Rhythm Association (EHRA), Society for Cardiovascular Angiography and Interventions (SCAI), TVT-The Heart Summit (TVT) and Cardiovascular Research Technologies (CRT). Trials with a broad relevance to the cardiology community and those with potential to change current practice were included.

RESULTS

A total of 93 key cardiology clinical trials were identified for inclusion. Interventional cardiology data included trials evaluating the use of new generation novel stent technology and new intravascular physiology strategies such as quantitative flow ratio (QFR) to guide revascularisation in stable and unstable coronary artery disease. New trials in acute coronary syndromes and intervention focused on long-term outcomes of optimal medical therapy (OMT), revascularisation in ischaemic dysfunction and left main (LM) intervention. Structural intervention trials included latest data on optimal timing and anticoagulation strategies in transcatheter aortic valve replacement (TAVR), in addition to expanding evidence in mitral and tricuspid valve interventions. Heart failure data included trials with sodium-glucose cotransporter 2 (SGLT2) inhibitors, iron replacement and novel drugs such as omecamtiv. Prevention trials included new data on proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and polypill strategies. In electrophysiology, new data regarding optimal timing of ablative therapy for atrial fibrillation (AF) in addition to novel screening strategies were evaluated.

CONCLUSION

This article presents a summary of key clinical cardiology trials published and presented during the past year and should be of interest to both practising clinicians and researchers.