Intravenous Thrombolysis With Tenecteplase Plus Thrombectomy Versus Thrombectomy Alone In Patients With A Large Ischemic Stroke: A Multicenter Randomized Controlled Trial (IVT-ALL-IN)

Overview

Stroke is a frequent and severe disease worldwide, representing the second leading cause of death and the leading cause of acquired disability. Over the last thirty years, reperfusion therapies have transformed the prognosis of ischemic stroke. For patients with acute ischemic stroke due to large-vessel occlusion (LVOS) and a small- to moderate-sized irreversibly injured tissue (core), the recommended treatment consists of intravenous thrombolysis (IVT) followed by mechanical thrombectomy (MT). However, for the fifth of LVOS patients with large core, MT has demonstrated its effectiveness, but the benefits of prior IVT remain unclear. In fact, no randomized trial has compared IVT+MT and MT alone in this population. Tenecteplase is increasingly replacing alteplase for LVOS due to two key advantages. First, it is administered as a single intravenous bolus, which speeds up treatment and transfers. Second, it improves reperfusion and functional outcomes in LVOS patients without large core. Emerging real-world evidence with tenecteplase reports lower rates of symptomatic intracranial hemorrhage than alteplase, suggesting superior overall efficacy. To date, no randomized trial has explored the benefit of tenecteplase in LVOS patients with large core. The IVT ALL IN trial is a French multicenter open randomized controlled trial with two parallel groups (IVT with tenecteplase followed by MT \[IVT+MT\] vs MT alone) and blinded endpoint assessment following a PROBE design. Its main objective is to assess which treatment strategy between IVT+MT and MT alone has a superior efficacy in terms of 3-month good functional outcome, defined as a modified Rankin scale (mRS) score ≤ 3 at 3 months, for LVOS patients with large core of the anterior circulation. Our trial will provide high-level evidence on the optimal reperfusion treatment strategy for LVOS patients with large ischemic core, who currently still have a low likelihood of achieving a favorable neurological outcome.

The IVT ALL IN trial is a French multicenter open-label randomized controlled trial with two parallel groups and blinded endpoint assessment following a PROBE design. Patients will be randomized between two treatment groups: the IVT with tenecteplase followed by MT group (IVT+MT; experimental group) or the MT alone group (control group). Randomization will be minimized on center, core size (very large \[ASPECTS 2-3\] versus large \[ASPECT 4-5\] infarcts) and treatment time window (within 4.5 hours vs others). We plan to include 486 adult patients with a pre-stroke mRS ≤ 1 presenting an anterior circulation LVOS eligible to MT within 24 hours of onset, or unknown onset with a DWI-FLAIR mismatch, with a large core defined as: * ASPECTS 2-5 or a core volume between 70 and 130 ml on MRI or perfusion CT for patients with process times compatible with IVT administration within 4.5 hours of onset or unknown onset with process times compatible with IVT administration within 4.5 hours of last seen well or unknown onset with a DWI-FLAIR mismatch * ASPECTS 2- 5 with a core volume ≤ 70 ml and core/perfusion mismatch \> 1.2 for patients with process times compatible with IVT administration within 4.5 and 9 hours of onset, defined as the mid-point between last known to be normal and symptoms constatation in case of unknown onset The primary endpoint is the rate of good functional outcome (independent ambulation) at 3 months defined as a modified Rankin scale (mRS) score of 0-3. In the six recently published trials comparing MT to best medical management for LVOS patients with large ischemic cores, rates of 3-month independent ambulation (mRS ≤ 3) range from 30% to 47% with a weighted average around 38%. In the first 5 RCTs that focused on the benefit of MT in LVOS, the minimal difference observed with MT was 13%. With these assumptions and for a global alpha risk of 0.05, a power of 0.8 and a bilateral test, the total number of patients to randomize would be 486 patients (243 in each arm) to increase the rate of good functional outcomes from 38% in the control group to 51% in the experimental group accounting for 5% of lost to follow-up and considering one interim analysis and the final analysis using a Lan and Demets method with an O'Brien \& Fleming type alpha risk expenditure function We plan a sequential analysis of the primary outcome with 2 analyses: one interim analysis after the evaluation of the primary outcome for one third of the planned number of participants randomized, and a final analysis at the end of the study (end of follow-up of the last randomized participant). This sequential analysis is planned to be able to stop the trial in case of a large difference between the 2 groups or for futility if the conditional power is too low. It is planned according to the Lan \& DeMets approach with a control of alpha risk according to the method of O'Brien \& Flemming.