Net Clinical Benefit of Non-vitamin K Antagonist Oral Anticoagulants for Venous Thromboembolism Prophylaxis in Patients With Cancer: A Systematic Review and Trade-Off Analysis From 9 Randomized Controlled Trials

Direct-Acting Oral Anticoagulant Therapy in Cancer Patients-A Review

Venous thromboembolism (VTE) is an important aspect in cancer patients. There are various pharmacological methods used for thrombotic event treatment. DOACs (direct-acting oral anticoagulants) are gaining popularity among both physicians and researchers and are slowly starting to replace VKAs (vitamin K antagonists), thus becoming a substitute or alternative option for LMWHs (low-molecular-weight heparins). In this article, we present DOACs' main therapeutic advantages and disadvantages in patients with cancer. The only major concern with using DOACs is the higher risk of bleeding; however, there are discrepancies in this matter. There are still some types of cancer for which DOACs are not recommended. Specific cancer types may influence the efficacy of DOAC therapy. Additionally, race and ethnicity may affect therapy in cancer patients with DOACs. A sizeable number of clinical trials are focused on comparing DOACs with other anticoagulants. The current guidelines of different scientific associations are not unanimous in their DOAC assessments. There is still a need for more evidence of DOACs' potential advantages over other methods of anticoagulation in cancer patients to facilitate their position in this recommendation. This literature review presents the current state of knowledge about the use of DOACs in patients with neoplastic growth.

A Network Comparison on Safety Profiling of Immune Checkpoint Inhibitors in Advanced Lung Cancer

Background

Immune checkpoint inhibitors (ICIs) have become one of the standard treatment options for advanced lung cancer. However, adverse events (AEs), particularly immune–related AEs (irAEs), caused by these drugs have aroused public attention. The current network meta-analysis (NMA) aimed to compare the risk of AEs across different ICI–based regimens in patients with advanced lung cancer.

Methods

We systematically searched the PubMed, EMBASE, and Cochrane Library databases (from inception to 19 April 2021) for relevant randomized controlled trials (RCTs) that compared two or more treatments, with at least one ICI administered to patients with advanced lung cancer. The primary outcomes were treatment–related AEs and irAEs, including grade 1–5 and grade 3–5. The secondary outcomes were grade 1–5 and grade 3–5 irAEs in specific organs. Both pairwise and network meta-analyses were conducted for chemotherapy, ICI monotherapy, ICI monotherapy + chemotherapy, dual ICIs therapy, and dual ICIs + chemotherapy for all safety outcomes. Node–splitting analyses were performed to test inconsistencies in network. Sensitivity analyses were adopted by restricting phase III RCTs and studies that enrolled patients with non–small cell lung cancer.

Results

Overall, 38 RCTs involving 22,178 patients with advanced lung cancer were enrolled. Both pooled incidence and NMA indicated that treatments containing chemotherapy increased the risk of treatment–related AEs when compared with ICI-based regimens without chemotherapy. As for grade 1–5 irAEs, dual ICIs + chemotherapy was associated with the highest risk of irAEs (probability in ranking first: 50.5%), followed by dual-ICI therapy (probability in ranking second: 47.2%), ICI monotherapy (probability in ranking third: 80.0%), ICI monotherapy + chemotherapy (probability in ranking fourth: 98.0%), and finally chemotherapy (probability in ranking fifth: 100.0%). In grade 3–5 irAEs, subtle differences were observed; when ranked from least safe to safest, the trend was dual ICIs therapy (60.4%), dual ICIs + chemotherapy (42.5%), ICI monotherapy (76.3%), ICI monotherapy + chemotherapy (95.0%), and chemotherapy (100.0%). Furthermore, detailed comparisons between ICI–based options provided irAE profiles based on specific organ/system and severity.

Conclusions

In consideration of overall immune–related safety profiles, ICI monotherapy + chemotherapy might be a better choice among ICI–based treatments for advanced lung cancer. The safety profiles of ICI–based treatments are various by specific irAEs and their severity.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero, identifier CRD42021268650

Net Clinical Benefit of Direct Oral Anticoagulants in Patients With Cancer and Venous Thromboembolism: A Systematic Review and Trade-Off Analysis

Background: Venous thromboembolism (VTE) is highly prevalent in cancer patients. Recent guidelines recommend considering direct oral anticoagulants (DOACs) for the treatment of cancer-associated thrombosis (CAT). However, direct head-to-head comparisons among DOACs are lacking, and almost no net clinical benefit (NCB) analysis has been performed in patients with CAT.

Methods: We systematically searched PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov for randomized controlled trials (RCTs) reporting on recurrent VTE, major bleeding, or clinically relevant bleeding events in patients with CAT who received DOACs and low-molecular-weight heparins. Relative risks (RRs) and 95% confidence intervals (95% CIs) were calculated using a random-effect model. Surface under the cumulative ranking curve (SUCRA) values were calculated, and a trade-off analysis was performed to estimate the NCB.

Results: Overall, four RCTs involving 2,894 patients were enrolled. DOACs were more effective than dalteparin in reducing the risk of recurrent VTE (RR: 0.62, 95% CI: 0.44–0.87), with a comparative risk of major bleeding (RR: 1.33, 95% CI: 0.84–2.11) and an increased risk of clinically relevant bleeding (RR: 1.45, 95% CI: 1.05–1.99). No significant difference was observed among individual anticoagulants in terms of recurrent VTE and major bleeding. With respect to the ranking of each anticoagulant for the primary outcome, edoxaban (SUCRA: 69.2) was more effective than dalteparin (SUCRA: 60.7), rivaroxaban (SUCRA: 60.7), and apixaban (SUCRA: 25.5) in reducing VTE recurrence. For major bleeding, apixaban (SUCRA: 76.3) had the highest cumulative ranking probability, followed by edoxaban (SUCRA: 66.4), dalteparin (SUCRA: 28.8), and rivaroxaban (SUCRA: 28.5). Similar results were observed for clinically relevant bleeding. In terms of both benefit and safety outcomes, DOACs, especially edoxaban, seemed to confer a better NCB profile than dalteparin.

Conclusions: DOACs are a safe and effective alternative therapy to dalteparin in patients with CAT. Among them, edoxaban might provide a good risk-to-benefit balance. However, because of the lack of head-to-head studies, further investigations are needed to confirm our findings.

Cancer-associated venous thromboembolism and the non-vitamin K antagonist oral anticoagulants: a review of clinical outcomes and patient perspectives

INTRODUCTION

Cancer-associated venous thromboembolism remains an important but challenging aspect in the treatment of patients with cancer. Recently, alternatives to injection of low-molecular-weight heparin (LMWH) have been introduced, the non-vitamin K antagonist oral anticoagulants (NOACs), which could potentially alleviate patients from burdensome daily injections.

AREAS COVERED

This review discusses the available evidence exploring the role of NOACs in the treatment and secondary prevention of cancer-associated venous thromboembolism, from randomized trials, observational data, contemporary guideline recommendations, and patient perspectives.

EXPERT OPINION

Edoxaban, rivaroxaban, and apixaban have proven attractive alternatives to LMWH for the treatment of cancer-associated venous thromboembolism. Contemporary guidelines have promptly endorsed the use of NOACs in patients with most cancer types. Nonetheless, issues remain regarding bleeding risk, interactions with medical cancer treatment, and the effectiveness and safety for extended treatment periods. There are head-to-head comparisons of the NOACs, and therefore no data favoring the use of one NOAC over the others. Patient's preferences are highly diverse and should be part of routine considerations when weighing risks and benefits associated with various available anticoagulant drugs.

Platelet Count and Bleeding in Patients Receiving Anticoagulant Therapy for Venous Thromboembolism: Lesson from the RIETE Registry

Major bleeding is one of the most dangerous complications for patients undergoing anticoagulant treatment for VTE. Several clinical scores have been planned to identify patients at higher risk of bleeding, and most of them take into consideration the number of platelets in particular if lower than normal. Here we report the clinical experience made with the RIETE registry concerning anticoagulant treatment in the presence of different values of platelets and their related risk of bleeding.

Direct versus conventional anticoagulants for treatment of cancer associated thrombosis: a pooled and interaction analysis between observational studies and randomized clinical trials

BACKGROUND

There are emerging observational studies (OSs) to assess real-world comparative effectiveness and safety of direct oral anticoagulants (DOACs) in cancer associated thrombosis (CAT). We conducted a pooled and interaction analysis to compare the treatment effect estimates of DOACs between OSs and randomized controlled trials (RCTs).

METHODS

We systematically searched PUBMED, EMBASE and Cochrane Library for OSs and RCTs that reported recurrent venous thromboembolism (VTE) and/or major bleeding events in CAT patients receiving DOACs and conventional anticoagulants [warfarin or low molecular-weight heparins (LMWHs)]. Relative risks (RRs) for OSs and RCTs were calculated using random-effects models separately, and interaction analyses were afterward applied to assess the comparability between OSs and RCTs.

RESULTS

Baseline characteristic was comparable between identified 10 OSs (35,142 patients) and 8 RCTs (2,602 patients). Overall, no significant difference of treatment effect estimates between OSs and RCTs was detected (Pinteraction: 0.42 for recurrent VTE; Pinteraction: 0.38 for major bleeding). DOACs significantly decreased the risk of recurrent VTE compared with conventional anticoagulants in CAT patients (RR: 0.74, 95% CI: 0.63-0.86, I2: 0% for OSs; RR: 0.65, 95% CI: 0.49-0.86; I2: 0% for RCTs), without increasing major bleeding risk (RR: 0.90, 95% CI: 0.76-1.07, I2: 24.0% for OSs; RR: 1.17, 95% CI: 0.72-1.88, I2: 26.2% for RCTs). Whereas, increased risk of gastrointestinal bleeding (GIB) was found with DOACs versus conventional anticoagulants in CAT patients (RR: 2.77, 95% CI: 1.35-5.68, I2: 0% for RCTs). Analyses of subgroups, based on comparators and follow-up duration, did not significantly affect results.

CONCLUSIONS

In this study, effectiveness and safety of DOACs versus conventional anticoagulants in CAT from OSs are in agreement with those from RCTs, confirming a low risk of recurrent VTE and similar risk of major bleeding in CAT patients receiving DOACs.

Net clinical benefit of non-vitamin K antagonist oral anticoagulants in atrial fibrillation and chronic kidney disease: a trade-off analysis from four phase III clinical trials

Background

Atrial fibrillation (AF) is quite prevalent in patient with chronic kidney disease (CKD). This study mainly investigated the net clinical benefit (NCB) property of non-vitamin K antagonist oral anticoagulants (NOACs) versus warfarin in patients with AF and CKD by a pooled-analysis.

Methods

A comprehensive search of Medline, Embase, Cochrane Library and Clinical Trials.gov Website was performed for eligible randomized controlled trials (RCTs) reporting the efficacy and safety outcomes according to renal function of NOACs. Pre-specified outcomes and their number of patients needed to treat (NNT), including stroke/systemic embolism (SSE), major bleeding, and all-cause death, were evaluated using a random-effects model. NCB that balanced SSE and major bleeding was calculated using Singer's method.

Results

Four phase III clinical trials including 70,952 patients were enrolled, 45,265 (64%) with CKD, and 25,687 (36%) without CKD; 41,942 (59%) taking NOACs and 29,010 (41%) taking warfarin. Risks of SSE [relative risk (RR): 0.80, 95% confidence interval (CI): 0.73-0.88, P<0.01], major bleeding (RR: 0.79, 95% CI: 0.66-0.96, P=0.017), and all-cause death (RR: 0.91, 95% CI: 0.84-0.99, P=0.031) were significantly lower in CKD patients with NOACs than those with warfarin, accompanying with a high absolute risk reduction (NNT: 182 for SSE; 122 for major bleeding; 196 for all-cause death). While NOACs were not superior to warfarin on SSE, major bleeding, and all-cause death in patients without CKD, the NCB of NOACs versus warfarin was progressively increased with the deterioration of renal function (NCB: 0.72 for no CKD, 1.59 for mild CKD, 2.74 for moderate CKD). Sensitivity analyses did not significantly affect the primacy results.

Conclusions

NOACs, compared with warfarin, provide a better clinical profile on SSE, major bleeding, all-cause death, and NCB in CKD patients.

Direct oral anticoagulants in patients with cancer

Purpose

This review summarizes the available evidence concerning direct oral anticoagulant (DOAC) use to treat venous thromboembolism (VTE) in patients with cancer as well as pertinent safety data on the use of DOACs in patients with both cancer and atrial fibrillation.

Summary

The introduction of DOACs into clinical practice changed the way thrombotic complications are managed and prevented in diverse patient populations, including VTE and atrial fibrillation. Low-molecular-weight heparins have been the standard of care for treating VTE in cancer patients due to superiority over vitamin K antagonists in preventing recurrent VTE. Therefore, widespread DOAC use for VTE in patients with active cancer has not been adopted.

Conclusion

Recent randomized clinical trials (SELECT-D, Hokusai VTE Cancer) have provided evidence that DOACs may have a role in treating VTE in cancer patients.

Net clinical benefit analysis of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation and chronic kidney disease: Protocol for a systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) is increasingly prevalent in chronic kidney disease (CKD) patients. The efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) in AF and CKD patients remains unknown. This systematic review and meta-analysis will mainly assess net clinical benefit (NCB) property of NOACs versus warfarin in patients with AF and CKD by a pooled-analysis.

METHODS

We will search Medline, Embase, Cochrane Library, and Clinical Trials.gov Website comprehensively for eligible randomized controlled trials that report the efficacy and safety outcomes according to renal function of NOACs. Relative risks and their 95% confidence intervals will be calculated using fixed- and random-effects models. Subgroup, sensitivity, and regression analyses will be performed to evaluate intertrial heterogeneity and bias of the results. NCB that balance stroke/systemic embolism (SSE) and major bleeding will be calculated using Singer's method.

RESULTS

This systemic review and meta-analysis will evaluate the NCB of NOACs versus warfarin via SSE, major bleeding and all-cause death in patients with CKD.

CONCLUSIONS

This study will provide new evidence for clinical profile of NOACs on SSE, major bleeding, all-cause death, and NCB in CKD patients.

PROSPERO REGISTRATION NUMBER

CRD42019116940.

A Renal Function Based Trade-Off Analysis of Non-vitamin K Antagonist Oral Anticoagulants in Nonvalvular Atrial Fibrillation

Background: Non-vitamin K antagonist oral anticoagulants (NOACs) depend on some degree of renal excretion, and no head-to-head comparisons based on renal function is available. This study mainly investigated the trade-off property of NOACs in nonvalvular atrial fibrillation (NVAF) with varying degrees of renal function.

Methods: A comprehensive search of Medline, Embase, Cochrane Library, and Clinical Trials.gov Website was performed for eligible randomized controlled trials (RCTs) that reported the efficacy and safety outcomes according to renal function of NOACs. Primary efficacy outcome was any Stroke or systemic embolism (S/SE). Major bleeding was considered as a primary safety outcome. Risk ratios (RRs) with their confidence intervals (CIs), the surface under the cumulative ranking curve (SUCRA), and trade-off analysis were conducted by renal function.

Results: Finally, 5 phase III Clinical Trials (72961 NVAF patients) comparing NOACs with warfarin in NVAF patients were included. In terms of normal renal function, dabigatran-150 mg was ranked first for efficacy (SUCRA: 90.3), and edoxaban-30 mg was ranked first for safety (SUCRA: 93.3). Dabigatran-110 mg/150 mg, and apixaban-5 mg were regarded as the most effective and reasonably safe interventions in the trade-off analysis. Regarding mild renal impairment, edoxaban-60 mg was ranked first for efficacy (SUCRA: 97.8), and edoxaban-30 mg was ranked first for safety (SUCRA: 99.5). Edoxaban-60 mg and dabigatran-150 mg were accounted as the most effective and reasonably safe interventions. With regards to moderate renal impairment, dabigatran-150 mg was ranked first for efficacy (SUCRA: 95.1), and edoxaban-15 mg was ranked first for safety (SUCRA: 98.2). Apixaban-2.5 mg and Edoxaban-30 mg was considered as the reasonably effective and the safest interventions.

Conclusions: Dabigatran-150 mg seems the most effective therapy in patients with normal renal function and moderate renal impairment, and edoxaban-60 mg in patients with mild renal impairment. Low dose edoxaban (15 and 30 mg) seems the safest intervention. Apixaban-2.5 mg and edoxaban-30 mg might be the best trade-off property in moderate renal insufficiency.

HIGHLIGHTS 

STUDY REGISTRATION: 

PROSPERO Identifier, CRD42017054235.

Survival benefits of oral anticoagulants in patients with pulmonary arterial hypertension: Protocol for a systematic review and meta-analysis

BACKGROUND

Pulmonary arterial hypertension (PAH) is an incurable disease with high mortality. Although most studies recommend anticoagulation treatment for idiopathic pulmonary arterial hypertension (IPAH), the survival benefits are uncertain. Therefore, the present paper provides a protocol to investigate this issue by a meta-analysis.

METHODS

An electronic search will be performed for randomized controlled trials (RCTs) or cohort studies that reported the interested efficacy data (pulmonary arterial pressure and survival advantage) in anticoagulants-treated patients with PAH. Hazard ratios with their confidence intervals will be calculated using a fixed- or random-effects model.

RESULTS

This study will provide the survival benefits of anticoagulants in PAH patients by pooling the results of individual studies.

CONCLUSION

The results will bring about vigorous evidence in this issue and guide both clinical decision-making and future research.

The optimal anticoagulant therapy for mechanical heart valves in a gallbladder cancer patient with hepatic metastases: A case report

RATIONALE

Developing an optimal anticoagulant strategy poses a challenging task in patients with mechanical heart valves (MHVs) throughout their lifetime. We report an optimal anticoagulant therapy in a cancer patient with hepatic metastases after MHV replacement.

PATIENT CONCERNS

A 68-year-old female with MHVs suffered from gallbladder cancer with hepatic metastases. Her international normalized ratio (INR) fluctuated owing to the declined hepatic function.

DIAGNOSES

Gallbladder cancer and hepatic metastases, with a history of mechanic aortic valve replacement and mitral valve replacement.

INTERVENTIONS

Warfarin was discontinued and Vitamin K1 was immediately administrated via intravenous infusion. low-molecular-weight heparin (LMWH) was regarded as a preferable option, and nadroparin at the dosage of 4100IU daily was administered.

OUTCOMES

No adverse event occurred during the patient's hospitalization and two-week follow up after discharge.

LESSONS

LMWH may represent a reasonable alternative regarding the inhibition of thrombus and bleeding in MHVs carriers with cancer and hepatic metastases.