Robin Conwit

The Clinical Trials Methodology Course (CTMC), given from 2014 to 2023, was conducted to educate early-career clinical investigators from various backgrounds in neurosciences in the design of clinical trials and to provide mentorship to enhance academic careers and retention plus improve research productivity and the likelihood of successful grant applications. This summary describes the rationale, history, structure, and trainee outcomes of the CTMC. The course used small groups, consisting of 1–2 clinical faculty advisor(s), 1 faculty biostatistician, and 2–4 trainees who met remotely approximately weekly over 12 weeks. Faculty and trainees then met for a 4-day in-person residential course. Follow-up activities included 2–3 follow-up remote meetings and a mock study section review of draft grant applications. The CTMC enrolled 243 trainees from 2014 to 2023 (excluding 2020) into Foundation (173) or other (70) tracks. Ninety-six percent of trainees remained in academic positions. Trainees published 7,666 peer-reviewed articles from their enrollment year to 2023 (mean 31.5 articles per trainee, or mean ± SD of 5.0 ± 5.1 articles per year per trainee). There were 7,120 unique articles; trainees were coauthors in 546. Of 173 Foundation Track trainees, 109 (63%) submitted an NIH grant as principal investigator or co-principal investigator, and 68 (62% of 109 submitters) were funded within a median of 3 years after course completion. Of the 243 total trainees, 91 (38%) were principal investigators for at least 1 NIH grant since their course participation to 2023. Trainees have participated as medical monitors, members of data and safety monitoring boards, investigators for NIH research networks, and faculty in the CTMC itself. CTMC has provided a robust foundation in clinical trial methodology in neuroscience research to a generation of clinical investigators.

BACKGROUND: Observational studies suggest that magnesium may have hemostatic effects. FAST-MAG (Field Administration of Stroke Therapy-Magnesium) was a pragmatic clinical trial of magnesium sulfate administered prehospital for acute clinical stroke syndromes and included patients with intracerebral hemorrhage. Exploratory secondary analysis by the treatment group found no reduction in hematoma expansion (HE) associated with magnesium treatment in intracerebral hemorrhage but did not consider serum magnesium levels achieved. We analyzed FAST-MAG intracerebral hemorrhage data for associations between serum magnesium level, HE, and early neurological deterioration, accounting for groupwise biases. METHODS: HE was defined as hematoma volume increase ≥3 mL within 24 hours and early neurological deterioration as ≥1-point Glasgow Coma Scale decline from arrival to hospital day 4. Comparing treatment and placebo groups confirmed biased availability of neuroimaging data. Therefore, HE and neurological deterioration were analyzed and stratified by treatment and placebo groups using univariate tests and adjusted logistic regression. RESULTS: Spontaneous intracerebral hemorrhage was present in 381 patients. Placebo patients had fewer serial neuroimaging studies available (123 [65.4%] versus 145 [75.1%]; P =0.038). Necessary data were available in 104 magnesium- and 85 placebo-treated patients (age, 64.9 [13.0] years; 67.7% male). In the magnesium group, higher magnesium level was associated with less HE (adjusted odds ratio, 0.64 per mg/dL [95% CI, 0.42–0.93]) and less neurological deterioration (adjusted odds ratio, 0.54 per mg/dL [95% CI, 0.33–0.82]). In the placebo group, magnesium level was not associated with either HE or neurological deterioration. CONCLUSIONS: Magnesium may exhibit a hemostatic effect that was only observable in the FAST-MAG magnesium treatment group. Equipoise should be maintained, and specific trials are needed. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00059332.

Background: Long-term disability after stroke is standardly assessed 3 months post-onset, using the modified Rankin Scale (mRS). The value of an early, day 4 mRS assessment for projecting the 3-month disability outcome has not been formally investigated. Methods: In this cohort of patients with acute cerebral ischemia and intracranial hemorrhage, we analyzed day 4 and day 90 mRS assessments in the NIH Field Administration of Stroke Therapy– Magnesium (FAST-MAG) Phase 3 trial. The performance of day 4 mRS, alone and as part of multivariate models, in predicting day 90 mRS was assessed using correlation coefficients, percent agreement, and the kappa statistics. Results: Among the 1573 acute cerebrovascular disease (ACVD) patients, 1206 (76.7%) had acute cerebral ischemia (ACI), while 367 (23.3%) had intracranial hemorrhage. Among all 1573 ACVD patients, day 4 mRS and day 90 mRS correlated strongly, Spearman’s rho=0.79, in unadjusted analysis with weighted kappa of 0.59. For dichotomized outcomes, simple carry-forward of the day 4 mRS performed fairly well in agreeing with day 90 mRS: mRS 0-1 (k=0.67), 85.4%; mRS 0-2 (k=0.59), 79.5%; fatal outcome, 88.3% (k=0.33). Correlations of 4d and 90d mRS were stronger for ACI than ICH patients, 0.76 vs 0.71. Conclusions: In this acute cerebrovascular disease patient cohort, assessment of global disability performed on day 4 is highly informative regarding long-term, 3-month mRS disability outcome, alone, and even more strongly in combination with baseline prognostic variables. The day 4 mRS is a useful measure for imputing the final patient disability outcome in clinical trials and quality improvement programs.

Background: To emphasize treatment speed for time-sensitive conditions, emergency medicine has developed not only the concept of the golden hour, but also the platinum half-hour. Patients with acute stroke treated within the first half-hour of onset have not been previously characterized. Methods: In this cohort study, we analyzed patients enrolled in the FAST-MAG (Field Administration of Stroke Therapy–Magnesium) trial, testing paramedic prehospital start of neuroprotective agent ≤2 hours of onset. The features of all acute cerebral ischemia, and intracranial hemorrhage patients with treatment starting at ≤30 m of last known well were compared with later-treated patients. Results: Among 1680 patients, 203 (12.1%) received study agents within 30 minutes of last known well. Among platinum half-hour patients, median onset-to-treatment time was 28 minutes (interquartile range, 25–30), and final diagnoses were acute cerebral ischemia in 71.8% (ischemic stroke, 61.5%, TIA 10.3%); intracranial hemorrhage in 26.1%; and mimic in 2.5%. Clinical features among platinum half-hour patients were largely similar to later-treated patients and included age 69 (interquartile range, 57–79), 44.8% women, prehospital Los Angeles Motor Scale median 4 (3–5), and early-postarrival National Institutes of Health Stroke Scale deficit 8 (interquartile range, 3–18). Platinum half-hour acute cerebral ischemia patients did have more severe prehospital motor deficits and younger age; platinum half-hour intracranial hemorrhage patients had more severe motor deficits, were more often female, and less often of Hispanic ethnicity. Outcomes at 3 m in platinum half-hour patients were comparable to later-treated patients and included freedom-from-disability (modified Rankin Scale score, 0–1) in 35.5%, functional independence (modified Rankin Scale score, 0–2) in 53.2%, and mortality in 17.7%. Conclusions: Prehospital initiation permits treatment start within the platinum half-hour after last known well in a substantial proportion of acute ischemic and hemorrhagic stroke patients, accounting for more than 1 in 10 enrolled in a multicenter trial. Hyperacute platinum half-hour patients were largely similar to later-treated patients and are an attainable target for treatment in prehospital stroke trials.

Background: Intracerebral hemorrhage (ICH) is the deadliest form of stroke. In observational studies, lower serum magnesium has been linked to more hematoma expansion (HE) and intracranial hemorrhage, implying that supplemental magnesium sulfate is a potential acute treatment for patients with ICH and could reduce HE. FAST-MAG (Field Administration of Stroke Therapy - Magnesium) was a clinical trial of magnesium sulfate started prehospital in patients with acute stroke within 2 hours of last known well enrolled. CT was not required prior to enrollment, and several hundred patients with acute ICH were enrolled. In this ancillary analysis, we assessed the effect of magnesium sulfate treatment upon HE in patients with acute ICH. Methods: We retrospectively analyzed data that were prospectively collected in the FAST-MAG study. Patients received intravenous magnesium sulfate or matched placebo within 2 hours of onset. We compared HE among patients allocated to intravenous magnesium sulfate or placebo with a Mann-Whitney U . We used the same method to compare neurological deficit severity (National Institutes of Health Stroke Scale) and global disability (modified Rankin Scale) at 3 months. Results: Among 268 patients with ICH meeting study entry criteria, mean 65.4±13/4 years, 33% were female, and 211 (79%) had a history of hypertension. Initial deficit severities were median (interquartile range) of 4 (3–5) on the Los Angeles Motor Scale in the field and National Institutes of Health Stroke Scale score of 16 (9.5–25.5) early after hospital arrival. Follow-up brain imaging was performed a median of 17.1 (11.3–22.7) hours after first scan. The magnesium and placebo groups did not statistically differ in hematoma volume on arrival, 10.1 (5.6–28.7) versus 12.4 (5.6–28.7) mL ( P =0.6), or HE, 2.0 (0.1–7.4) versus 1.5 (−0.2 to 8) mL ( P =0.5). There was no difference in functional outcomes (modified Rankin Scale score of 3–6), 59% versus 50% ( P =0.5). Conclusions: Magnesium sulfate did not reduce HE or improve functional outcomes at 90 days. A benefit for patients with initial hypomagnesemia was not addressed. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00059332.

Background: There are limited data on the trajectory of recovery and long-term functional outcomes after intracerebral hemorrhage (ICH). Most ICH trials have conventionally assessed outcomes at 3 months following the footsteps of ischemic stroke. The i-DEF trial (Intracerebral Hemorrhage Deferoxamine Trial) assessed modified Rankin Scale (mRS) longitudinally at prespecified time points from day 7 through the end of the 6-month follow-up period. We evaluated the trajectory of mRS among trial participants and examined the effect of deferoxamine on this trajectory. Methods: We performed a post hoc analysis of the i-DEF trial, a multicenter, randomized, placebo-controlled, double-blind, futility-design, phase 2 clinical trial, based on the actual treatment received. Favorable outcome was defined as mRS score of 0–2. A generalized linear mixed model was used to evaluate the outcome trajectory over time, as well as whether the trajectory was altered by deferoxamine, after adjustments for randomization variables, presence of intraventricular hemorrhage, and ICH location. Results: A total of 291 subjects were included in analysis (145 placebo and 146 deferoxamine). The proportion of patients with mRS score of 0–2 continually increased from day 7 to 180 in both groups (interaction P P =0.0010). Between day 90 and 180, the deferoxamine group improved ( P =0.0001), whereas there was not significant improvement in the placebo arm ( P =0.3005). Conclusions: A large proportion of patients continue to improve up to 6 months after ICH. Future ICH trials should assess outcomes past 90 days for a minimum of 6 months. In i-DEF, treatment with deferoxamine seemed to accelerate and alter the trajectory of recovery as assessed by mRS. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02175225.

Background and Purpose: Primary stroke center (PSC) certification is associated with improvements in stroke care and outcome. However, these improvements may reflect a higher baseline level of care delivery in hospitals eventually achieving certification. This study examines whether advancements in acute stroke care at PSCs are due to certification or factors intrinsic to the hospital. Methods: Data was obtained from the Field Administration of Stroke Therapy-Magnesium (FAST-MAG) trial with participation of 40 Emergency Medical System agencies, 315 ambulances, and 60 acute receiving hospitals in Los Angeles and Orange Counties. Subjects were transported to one of three types of destinations: PSC certified hospitals (PSCs), hospitals that were not PSCs at time of enrollment but would later become certified (pre-PSCs), and hospitals that would never be certified (non-PSCs). Metrics of acute stroke care quality included time arrival to imaging, use of intravenous tPA, and arrival to treatment. Results: Of 1700 cases, 856(50%) were at certified PSCs, 529(31%) were at pre-PSCs, and 315 (19%) were at non-PSCs. Mean(SD) was 33min (±76.1) at PSCs, 47(±86.6) at pre-PSCs, and 49(±71.7) at non-PSCs. Of 1223 cerebral ischemia cases, rate of tPA utilization was 43% at PSCs, 27% at pre-PSCs, and 28% at non-PSCs. Mean ED arrival to thrombolysis was 71(±32.7) at PSC, 98(±37.6) at pre-PSC, and 95(±45.0) at non-PSCs. PSCs had improved time to imaging (p=0.014), percent tPA use (p<0.001), and time to treatment (p=0.003). Conclusions: Stroke care at hospitals prior to PSC certification is equivalent to care at non-PSCs.