BACKGROUND: The benefit-risk profile of tenecteplase in the elderly patients with acute ischaemic stroke (AIS) is uncertain. We sought to investigate the efficacy and safety of 0.25 mg/kg tenecteplase compared with alteplase for AIS patients aged ≥80 years. METHODS: We performed a post hoc analysis of the Tenecteplase Reperfusion Therapy in Acute Ischaemic Cerebrovascular Events-2 Trial, a randomised, phase 3, non-inferiority clinical trial. Disabling AIS patients aged ≥80 years who initiated intravenous thrombolytics within 4.5 hours of symptom onset were enrolled from June 2021 to May 2022 across 53 centres in China and were randomly allocated to receive 0.25 mg/kg tenecteplase or 0.9 mg/kg alteplase. The primary efficacy outcome was the proportion of participants with a modified Rankin Scale (mRS) score of 0-1 at 90 days. Symptomatic intracranial haemorrhage (sICH) within 36 hours was the safety outcome. RESULTS: Of 137 participants, mRS 0-1 at 90 days occurred in 37 (49.3%) of 75 in the tenecteplase group vs 20 (33.9%) of 59 in the alteplase group (risk ratio (RR) 1.47, 95% CI 0.96 to 2.23). sICH within 36 hours was observed in 3 (4.0%) of 76 in the tenecteplase group and two (3.3%) of 61 in the alteplase group (RR 1.30, 95% CI 0.20 to 8.41). CONCLUSIONS: The risk-benefit profile of tenecteplase thrombolysis was preserved in the elderly patients, which lends further support to intravenous 0.25 mg/kg tenecteplase as an alternative to alteplase in these patients.