Table 1.

Characteristics of studies on extended anticoagulation after incident VTE (adapted from Albertsen et al.).

Intervention *	Study, Year	Comparison	No. Patients Enrolled	Patients with Index PE	Treatment Duration	Recurrence Proportion (%) in Intervention * vs. Comparison Group	Recurrence risk: HR; 95% CI	Major or CRNM Bleeding in Intervention * Group: HR; 95% CI
Dabigatran	RE-SONATE, 2013 [34]	Placebo vs. dabigatran 150 mg BID	1343	33%	6–18 months	0.4% vs. 5.6%	0.08; 0.02–0.25	2.92; 1.52–5.60
	RE-MEDY, 2013 [34]	Warfarin vs. dabigatran 150 mg BID	2856	35%	18–36 months	1.8% vs. 1.3%	1.44; 0.78–2.64	0.54; 0.41–0.71.
Rivaroxaban	EINSTEIN Extension, 2010 [35]	Placebo vs. rivaroxaban 20 mg OD	1196	38%	6–12 months	1.3% vs. 7.1%	0.18; 0.09–0.39	5.19; 2.3–11.7.
	EINSTEIN Choice, 2017 [36]	Aspirin 100 mg OD vs. rivaroxaban 20 mg OD rivaroxaban 10 mg OD	3365	49%	12 months	Riva 20 mg: 1.5% Riva 10 mg: 1.2% vs. Aspirin: 4.4%.	Riva 20 mg vs. aspirin: 0.34; 0.20–0.59. Riva 10 mg vs. aspirin: 0.26; 0.14–0.47.	1.59; 0.94–2.69. 1.16; 0.67–2.03.
Apixaban	AMPLIFY Extension, 2013 [37]	Placebo vs. apixaban 5 mg BID vs. apixaban 2.5 mg BID	2486	35%	12 months	Apixaban 5 mg: 1.7% Apixaban 2.5 mg: 1.7% vs. Placebo: 8.8%	Apixaban 5 mg vs. placebo: 0.36; 0.25–0.53. Apixaban 2.5 mg vs. placebo: 0.33; 0.22–0.48.	1.62; 0.96–2.73. 1.20; 0.69–2.10.
Aspirin	WARFASA, 2012 [38]	Placebo vs. aspirin 100 mg OD	402	40%	≥24 months	6.6% vs. 11.2%	0.58; 0.36–0.93.	0.98; 0.24–3.96.
	ASPIRE, 2012 [39]	Placebo vs. aspirin 100 mg OD	822	30%	2–4 years	4.8% vs. 6.5%	0.74; 0.52–1.05.	1.1% per year with aspirin (vs. 0.6%).

BID = twice a day; CI = confidence interval; CRNM = clinically relevant non-major; HR = hazard ratio; OD = once a day; PE = pulmonary embolism; Riva = rivaroxaban; VTE = venous thromboembolism. * ‘Intervention’ denotes the anticoagulant drug tested in the table.