TESLA 1-Year
(2026)Objective
In patients with large-core anterior circulation ischemic stroke selected by noncontrast CT (ASPECTS 2-5), does intra-arterial thrombectomy plus medical management improve 1-year functional outcomes vs medical management alone?
Study Summary
• Functional independence (mRS 0-2) at 1 yr: 34/144 (23.6%) IAT vs 9/133 (6.8%) MM (RD 16.8%, 95% CI 8.7-25.0; P<0.001; RR 3.49, 95% CI 1.74-7.00).
• Independent ambulation (mRS 0-3): 51/144 (35.4%) IAT vs 24/133 (18.0%) MM (RD 17.4%, 95% CI 7.2-27.6; P<0.001).
• mRS ordinal shift favored IAT: common OR 1.82 (95% CI 1.16-2.86; P=0.005).
• EQ-5D-5L quality of life: mean 60.3 (SD 28.7, n=79) IAT vs 49.3 (SD 24.2, n=66) MM (MD 10.0, 95% CI 5.0-21.0; P=0.003).
• All-cause mortality at 1 yr: 62/144 (43.1%) IAT vs 62/133 (46.6%) MM (RD -3.5%, 95% CI -15.3 to 8.2; P=0.42).
• All sensitivity analyses (per-protocol, core-lab ASPECTS, multivariable, LOCF, tipping-point) supported the primary result direction.
• Findings exploratory/descriptive — the original 90-day primary endpoint was neutral and secondary endpoints were not adjusted for multiplicity.
Intervention
Intra-arterial mechanical thrombectomy (IAT) plus best medical management vs medical management alone
Inclusion Criteria
Age 18-85 yr; within 24 h of last known well; NIHSS ≥6; ICA or MCA occlusion; baseline NCCT ASPECTS 2-5; premorbid mRS 0-1
Study Design
Arms: 302 randomized total; ITT cohort N=300: Intra-arterial thrombectomy + MM (n=152 ITT; 144 with 1-yr data) vs Medical management alone (n=148 ITT; 133 with 1-yr data)
Patients per Arm: 152 vs 148 (N=300 ITT; N=302 randomized; 277 with complete 1-yr functional data; 23 lost to follow-up or withdrew)
Outcome
• mRS 0-2: 34/144 (23.6%) vs 9/133 (6.8%); RD 16.8% (8.7-25.0); P<0.001; RR 3.49 (1.74-7.00).
• mRS 0-3: 51/144 (35.4%) vs 24/133 (18.0%); RD 17.4% (7.2-27.6); P<0.001.
• Ordinal mRS shift: cOR 1.82 (1.16-2.86); P=0.005.
• 1-yr mRS distribution IAT vs MM: 0: 6.3% vs 0%; 1: 6.3% vs 2.3%; 2: 11.1% vs 3.8%; 3: 11.8% vs 11.3%; 4: 14.6% vs 23.3%; 5 or 6: 50.0% vs 58.6%.
• EQ-5D-5L: 60.3 (SD 28.7, n=79) vs 49.3 (SD 24.2, n=66); MD 10.0 (5.0-21.0); P=0.003.
• All-cause mortality 1 yr: 62/144 (43.1%) vs 62/133 (46.6%); RD -3.5% (-15.3 to 8.2); P=0.42.
• Sensitivity: per-protocol MD 1.17 (0.32-2.02), posterior probability 0.996; core-lab ASPECTS MD 1.37 (0.53-2.22), P=0.002; multivariable MD 1.09 (0.37-1.81), P=0.003; LOCF MD 1.04 (0.28-1.79), P=0.007; tipping-point MD 0.79 (0.01-1.57), P=0.05.
Bottom Line
At 1 year, thrombectomy for NCCT-selected large-core anterior circulation stroke was associated with better utility-weighted mRS (adjusted MD 1.18, posterior probability 0.999), higher functional independence (23.6% vs 6.8%), better quality of life, and no difference in mortality. Findings are exploratory/descriptive because the 90-day primary endpoint was neutral, but support NCCT-alone selection as a lower-barrier strategy warranting further study.
Major Points
- Multicenter, open-label, blinded-endpoint RCT at 47 US stroke centers; 302 randomized, 300 in ITT (152 IAT, 148 MM); 277 with complete 1-yr functional data (144 IAT, 133 MM); 23 lost to follow-up or withdrew.
- Primary 1-yr endpoint (utility-weighted mRS 0-10; higher=better): IAT 3.65 (SD 0.22) vs MM 2.78 (SD 0.17); bayesian adjusted MD 1.18 (95% CrI 0.42-1.93); posterior probability of superiority 0.999 (prespecified threshold 0.975).
- Functional independence (mRS 0-2) at 1 yr: 34/144 (23.6%) IAT vs 9/133 (6.8%) MM; RD 16.8% (95% CI 8.7-25.0%); P<0.001; risk ratio 3.49 (95% CI 1.74-7.00).
- Independent ambulation (mRS 0-3): 51/144 (35.4%) IAT vs 24/133 (18.0%) MM; RD 17.4% (95% CI 7.2-27.6%); P<0.001. Ordinal mRS shift: common OR 1.82 (95% CI 1.16-2.86); P=0.005.
- EQ-5D-5L index (higher=better QoL): 60.3 (SD 28.7, n=79) IAT vs 49.3 (SD 24.2, n=66) MM; MD 10.0 (95% CI 5.0-21.0); P=0.003.
- All-cause mortality at 1 yr: 62/144 (43.1%) IAT vs 62/133 (46.6%) MM; RD -3.5% (95% CI -15.3 to 8.2%); P=0.42 — no mortality difference.
- Categorical mRS at 1 yr, IAT vs MM: mRS 0 (6.3% vs 0%), mRS 1 (6.3% vs 2.3%), mRS 2 (11.1% vs 3.8%), mRS 3 (11.8% vs 11.3%), mRS 4 (14.6% vs 23.3%), mRS 5 or 6 (50.0% vs 58.6%).
- All 5 sensitivity analyses (per-protocol, core-lab ASPECTS, multivariable, LOCF, tipping-point) confirmed direction of the primary finding, though tipping-point was borderline (MD 0.79, 95% CI 0.01-1.57; P=0.05).
- Functional independence in the IAT group numerically increased between 90 days and 1 year, while it declined in the MM group — potentially reflecting large-core tissue decay natural history, deconditioning, unmeasured rehab intensity differences, or baseline imbalances.
- Baseline imbalance: IAT group slightly younger (median 66 [IQR 54-74] vs 68 [59.5-76.5] yr) and higher diabetes prevalence (28.5% vs 16.8%).
Study Design
- Study Type
- Multicenter, open-label, blinded-endpoint randomized clinical trial (extended 1-year follow-up analysis)
- Randomization
- Yes
- Blinding
- Open-label with blinded end-point assessment
- Sample Size
- 300
- Follow-up
- 1 year (prespecified secondary endpoints); parent trial primary endpoint at 90 days
- Centers
- 47
- Countries
- USA
Primary Outcome
Definition: Mean utility-weighted mRS score at 1 year (range 0-10; higher scores indicate preferable functional states), calculated using standard utility multipliers (Chaisinanunkul 2015)
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 2.78 (SD 0.17) [n=133] | 3.65 (SD 0.22) [n=144] | - | Posterior probability of superiority = 0.999 (prespecified threshold ≥0.975) |
Limitations & Criticisms
- Findings are exploratory and descriptive because the prespecified primary 90-day endpoint was neutral, so 1-year superiority does not overcome the trial's original negative result.
- Secondary endpoints not adjusted for multiplicity — inflated risk of false-positive findings across multiple 1-year analyses.
- Open-label design creates potential performance bias from unblinded postprocedural rehabilitation intensity differences between arms.
- Asymmetric 1-year attrition (23 lost/withdrew) and tipping-point sensitivity analysis borderline (P=0.05) — result vulnerable to missing-data assumptions.
- Baseline imbalance in the 1-year cohort: IAT arm slightly younger (median 66 vs 68 yr) and higher diabetes prevalence (28.5% vs 16.8%) — could partly explain observed differences.
- External validity to lower-resource regions unestablished; conducted entirely within highly optimized US stroke networks.
- Unmeasured rehabilitation intensity between arms could confound the observed divergence in mRS 0-2 rates between 90 days and 1 year.
- EQ-5D-5L completion incomplete (n=79 IAT, n=66 MM) — quality-of-life analysis subject to selection bias among survivors.
Citation
JAMA. Published online August 3, 2026. DOI: 10.1001/jama.2026.12814