OBJECTIVES: To establish the average peak and trough concentrations of apixaban and rivaroxaban from real-world studies.

METHODS: PubMed, Scopus, and Web of Science were searched until October 2023 for observational studies reporting apixaban and rivaroxaban concentrations. Meta-regression was used to examine factors influencing these concentrations.

RESULTS: Sixteen studies involving 1054 apixaban and 1321 rivaroxaban patients were pooled using random-effects model. Mean apixaban peak concentrations were 157 ng/mL (95% CI, 127-187) for 2.5 mg and 228 ng/mL (95% CI, 204-252) for 5 mg, with trough concentrations of 77 ng/mL (95% CI, 56-98) and 113 ng/mL (95% CI, 101-124), respectively. Mean rivaroxaban peak concentrations were 168 ng/mL (95% CI, 104-232) for 10 mg, 225 ng/mL (95% CI, 192-257) for 15 mg, and 229 ng/mL (95% CI, 193-264) for 20 mg, with trough concentrations of 23 ng/mL (95% CI, 13-32), 31 ng/mL (95% CI, 26-36), and 36 ng/mL (95% CI, 25-47), respectively. Meta-regression revealed age and creatinine clearance correlated with apixaban peak concentrations. Creatinine clearance correlated with apixaban and rivaroxaban trough concentrations.