in the ARAMIS trial.
The trial was presented by Thanh Nguyen, MD, Boston Medical Center, at the International Stroke Conference presented by the American Stroke Association, a division of the American Heart Association.
“Given the ease of administration, less intensive monitoring, low cost, and safety profile of dual antiplatelet therapy, the current findings support the use of dual antiplatelet in this population,” Dr. Nguyen concluded.
In a comment on the trial, Pooja Khatri, MD, professor of neurology at the University of Cincinnati, and lead investigator of the previous PRISMS study of tissue plasminogen activator (tPA) or alteplase in mild stroke, said the results reinforced the current recommendations of giving dual antiplatelet therapy but not alteplase to these patients.
Noting that the standard of care is now to give dual antiplatelet therapy to these patients, Dr. Khatri said: “These data reassure that this remains the right way to go.”
She added that her take-home message from the study would be: “Keep giving dual antiplatelet therapy, and we may be doing more harm than good with alteplase in this patient population.”
Introducing her presentation, Dr. Nguyen explained that mild ischemic stroke, defined as having a National Institutes of Health Stroke Scale (NIHSS) score of 5 or less, comprises half of ischemic stroke patients in the United States. But the benefit of thrombolysis in patients with minor ischemic stroke that is not disabling is unknown.
A subgroup analysis of one of the major thrombolysis trials (IST-3) found that a higher proportion of patients with mild ischemic stroke who were treated within 3 hours of symptom onset were alive and independent at 6 months if they had been given thrombolysis (84%), compared to 65% in the control group who received standard medical treatment.
This led to the first randomized trial (PRISMS) dedicated to patients with mild nondisabling stroke, which found that alteplase given within 3 hours of symptom onset did not increase the likelihood of a good functional outcome at 90 days in comparison with single-agent aspirin. The study was unfortunately terminated early for administrative reasons, and no definitive conclusions could be drawn on the basis of these results, Dr. Nguyen reported.
In 2018, the American Heart Association/American Stroke Association guidelines indicated that for patients who present within 3 hours of symptom onset with mild ischemic stroke that was judged to be nondisabling, thrombolysis with intravenous alteplase could be considered, she noted.
In the meantime, dual antiplatelet therapy was shown to be safe and effective in the POINT and CHANCE trials in patients presenting with minor stroke within 12 or 24 hours, and the CHANCE trial also found a benefit in reducing recurrent stroke that was most effective in the first 2 weeks.
The current ARAMIS trial was therefore conducted to evaluate dual antiplatelet therapy in comparison with thrombolysis for patients with acute minor stroke (NIHSS 5 or less) who presented within 4.5 hours of symptom onset and were without clearly disabling deficit.
The trial was conducted in 38 hospitals in China and included 760 patients (median NIHSS score of 2) who were randomly assigned to receive intravenous alteplase at the standard dose of 0.9 mg/kg, followed by guideline-based antiplatelet treatment, or dual antiplatelet therapy (clopidogrel 300 mg plus 100 mg aspirin loading dose followed by 10 to 14 days of aspirin 100 mg and clopidogrel 75 mg).
The trial was designed to assess noninferiority of dual antiplatelet therapy to alteplase with noninferiority margin of –4.5%.
In the modified intention-to-treat analysis, which included 722 patients, the primary outcome (excellent functional outcome, defined as a Modified Rankin Scale score of 0 or 1 at 90 days) occurred in 93.8% of patients in the dual antiplatelet therapy group and in 91.4% of the alteplase group. This gave a difference of 2.4%, which fell within the limits for noninferiority (P = .0002 for noninferiority test).
“Therefore, this was a positive trial,” Dr. Nguyen stated.
About 20% of patients crossed over from the dual antiplatelet group to the thrombolysis group, and about 16% of patients crossed over from the thrombolysis group to the dual antiplatelet group. But a per-protocol and an “as treated” analysis showed results similar to those of the main intention-to-treat analysis.
Secondary outcomes were largely similar between the two groups other than early neurologic deterioration, which was less common in the dual antiplatelet therapy group.
In terms of safety, symptomatic intracranial hemorrhage occurred in 0.3% (1/369) in the dual antiplatelet group and in 0.9% (3/350) in the alteplase group, a nonsignificant difference.
Events of “any bleeding” occurred in more patients in the thrombolysis group (5.4%) than in the dual antiplatelet therapy group (1.6%), and this difference was significant (P = .01).
Subgroup analysis showed a trend toward benefit of alteplase for patients with higher NIHSS score at baseline (NIHSS > 3). Otherwise, the other subgroups looked similar to the main results.
Dr. Nguyen pointed out one limitation of the study – that dual antiplatelet therapy was updated to standard treatment in this target population in the 2019 AHA/ASA guidelines.
In her discussion of the study, Dr. Khatri suggested that the ARAMIS results were what might have been expected.
“Dual antiplatelet therapy is designed to prevent stroke. Even in the POINT trial, dual antiplatelet therapy showed no effect on 90-day functional outcome. It was really about prevention. The PRISMS trial suggested that alteplase was also unlikely to improve 90-day functional outcome in this population of patients with mild and not clearly disabling stroke. So, it is not surprising that dual antiplatelet therapy was noninferior to alteplase for 90-day functional outcome for both those reasons,” she explained.
“That being said, while designed as a noninferiority study, it is interesting to note that alteplase again showed no evidence of treatment effect compared to antiplatelet therapy, affirming what was observed in the prematurely terminated PRISMS trial,” Dr. Khatri added.
In a discussion of the study at an ISC 2023 highlights session, ISC program chair Tudor Jovin, MD, Cooper Neurological Institute, Cherry Hill, N.J., said: “This is very important data and it’s actually the first completed trial that examines this question.”
But, he added, “I think we need to refine our knowledge about what a nondisabling stroke actually is. You could argue that every stroke is disabling. I think we need more clarity on this definition, as in practice, many clinicians still give tPA on account of these mild strokes still being disabling.”
The ARAMIS trial was funded by the National Key R&D Program of China and the Science and Technology Project Plan of Liaoning Province. Dr. Nguyen reports research support from Medtronic that was not related to the current study.
A version of this article first appeared on Medscape.com.