Methods: The FIRST Trial is a prospective, multicenter, natural history study of a stroke cohort eligible for but untreated by mechanical thrombectomy presenting within 8 hrs of symptom onset from a large vessel occlusion and a NIHSS of at least 10. The primary endpoint is functional outcome at 90 days as defined by a mRS 0-2. Results are reported from an interim analysis.
Results: Fifty-nine (59) patients were enrolled and met study criteria for this interim analysis. The mean age was 68.2 ± 17 years; median NIHSS was 18 (5-34). Target vessel occlusions were in the ICA (35.7%), MCA (60.7%), and other (3.6%). At admission, the TIMI 0-1 rate was 89% (49/55), and the TICI 0-1 rate was 89% (48/54). Of these, only 10% (3/30) showed spontaneous recanalization (TIMI 2-3 or TICI 2a-3). Eleven of 55 (20%) patients achieved a good 90-day outcome, and 24 of 59 (40.7%) died. The serious adverse event rate was 52.6% (30/57), including respiratory failure (8 cases) and pneumonia (4 cases). A total of 6 (10%) patients suffered intracerebral hemorrhage (ICH). Below is a comparison of the MCA cohort vs. PROACT II placebo patients.
Conclusion: Compared with PROACT II placebo patients, the stroke cohort eligible for mechanical thrombectomy who were untreated have a lower rate of recanalization and worse outcome. These results indicate it may not be appropriate to use the PROACT placebo patients as historical controls for mechanical thrombectomy trials.