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Hanley, Daniel F.

https://orcid.org/0000-0002-9536-4258

Mayo Clinic

Johns Hopkins University

Citations 30

Neonatal Survival After Serial Amnioinfusions for Anhydramnios Due to Fetal Kidney Failure
Baschat, Ahmet A., Johnson, Anthony , Blumenfeld, Yair J., Schenone, Mauro H., Gebb, Juliana , Moldenhauer, Julie S., Zaretsky, Michael V. , Chmait, Ramen H., Gonzalez, Juan M., Rl, Miller, Krispin, Eyal , Shamshirsaz, A H A, Bligard, Katherine H. , Kalan, Amanda, Cortes, Magdalena Sanz, Bendel-Stenzel, Ellen, Menon, Shina , Wong, Cynthia, Kwak, Cecilia, Gallup, J Y, McKenna, Kristin, Marron, L, Tran, Cheryl L. , Behrendt, Nicholas, Galan, Henry L. , Samuels, Joshua, Swinford, Rita, Rosner, Mara, Kush, Michelle L, Nasr, Isam, Vasu, Samhita , Boss, Renee D. , Jelin, Angie C., Thompson, Richard E. , Davis, Jonathan M. , Warren, Daniel , Atkinson, Meredith A. , Gebb, Juliana S , Menon, Shina , Miller, Jena L. , Baschat, Ahmet , Blumenfeld, Yair J. , Schenone, Mauro H , Moldenhauer, Julie S. , Chmait, Ramen H. , Gonzalez, Juan, Cortes, Magdalena Sanz , Moon‐Grady, Anita J. , Bendel‐Stenzel, Ellen , Grimm, Paul, Marron, Leah, Hanna, Christian , Swinford, Rita D., Keiser, Amaris , Rosner, Mara , Nasr, Isam W. , Boss, Renee Denise , Jelin, Angie Child , Hanley, Daniel F.

JAMA | July 1, 2026 | Volume: 336 | Issue: 6 | Pages: 473

10.1001/jama.2026.8568 Get It

Importance Anhydramnios from fetal kidney failure causes lethal pulmonary hypoplasia. Serial amnioinfusions have shown promise in mitigating pulmonary disease from bilateral renal agenesis, but efficacy and safety for other causes of fetal kidney failure are unproven. Objective To assess the efficacy of serial amnioinfusions initiated before 26 weeks’ gestation to mitigate lethal pulmonary hypoplasia in cases of anhydramnios due to fetal kidney failure. Design, Setting, and Participants Prospective, nonrandomized clinical trial conducted at 13 US fetal therapy centers from December 2018 to February 2025. Outcomes for maternal-fetal pairs with anhydramnios before 22 weeks’ gestation due to fetal kidney failure without bilateral renal agenesis are reported; data collection for surviving infants continued until February 13, 2026. Exposure Thirty-two participants underwent serial amnioinfusions with isotonic fluid beginning before 26 weeks’ gestation. Main Outcomes and Measures The primary end point was neonatal survival for 14 days or longer with dialysis access placement. Secondary outcome measures of survival to discharge home and kidney transplant are reported. Results Twenty-nine of 32 participants (91%) had a live birth, with a median (IQR) gestational age at delivery of 34 weeks 1 day (31 weeks 5 days to 34 weeks 6 days). All participants delivered before 37 weeks’ gestation. No unexpected serious maternal adverse events occurred, and the most common maternal complications were preterm prelabor rupture of membranes in 19 participants (56%) and chorioamniotic separation in 10 (29%). The primary outcome occurred in 19 (65.5%) of 29 live-born neonates (95% CI, 45.7%-82.1%). Factors associated with survival to the primary outcome included receiving more amnioinfusions (median [IQR], 14 [9-18] in survivors vs 7 [4-11] in nonsurvivors; P = .01), longer time interval from first amnioinfusion to preterm prelabor rupture of membranes (63.5 [60.5-74.5] days in survivors vs 29.0 [22.0-56.0] days in nonsurvivors; P = .01), gestational age greater than 32 weeks (79% of survivors vs 38% of nonsurvivors; P = .03), and higher birth weight (2029 [1770-2250] g in survivors vs 1635 [1185-1915] g in nonsurvivors; P = .01). Fourteen live-born infants (48%) survived to hospital discharge at a median (IQR) age of 4.7 (3.4-5.7) months. Of the 11 infants surviving to date, 7 (64%) have undergone kidney transplant between ages 2 years to 5 years. Conclusions and Relevance Serial amnioinfusions mitigated lethal pulmonary hypoplasia in neonates with anhydramnios due to fetal kidney failure. Significant neonatal morbidity and mortality independent of early lung function was noted. Factors associated with survival were consistent with the Renal Anhydramnios Fetal Therapy trial’s bilateral renal agenesis cohort, suggesting common mechanistic pathways for mitigating pulmonary hypoplasia. Trial Registration ClinicalTrials.gov Identifier: NCT03101891
Recurrent Symptomatic Hemorrhage in Cerebral Cavernous Malformations After Discontinuation of Atorvastatin or Placebo
Ali, Bader , Shenkar, Robert, Lee, Justine J., Alcazar‐Félix, Roberto J. , Thompson, Richard E., Stadnik, Agnieszka , Sader, Georgio , Polster, Sean P. , Flemming, Kelly D. , Liao, James K. , Sorrentino, MJ, Girard, R., Hanley, Daniel F., Awad, Issam A., Shenkar, Robert , Shenkar, Robert , Lee, Justine , Hanley, Daniel F , Awad, Issam , Alcazar-Felix, Roberto J , Flemming, Kelly D , Polster, Sean P , Sorrentino, Matthew J., Girard, Romuald , Hanley, Daniel F. , Awad, Issam A.

Journal of the American Heart Association | January 29, 2026 | Volume: 15 | Issue: 3 | Pages: No page available

10.1161/jaha.125.046943 Get It

Background A recent randomized prospective controlled trial demonstrated that atorvastatin for up to 2 years was safe but did not significantly alter rebleeding in cerebral cavernous malformations. However, any consequences of discontinuing atorvastatin remain unknown. We hypothesized that symptomatic hemorrhage (SH) recurs more frequently in cerebral cavernous malformations after discontinuation of atorvastatin than placebo. Methods We conducted a 12‐month posttreatment follow‐up of patients enrolled in the Atorvastatin Therapy in Cavernous Angiomas with Symptomatic Hemorrhage Exploratory Proof of Concept (AT CASH EPOC) trial (41 randomized to atorvastatin, 39 to placebo) to identify potential recurrent SH after trial drug discontinuation. Every SH was adjudicated by review of imaging and corresponding symptoms. Patients were excluded from follow‐up for <90% compliance with study drug, for its discontinuation <3 months after trial enrollment, for statin reinitiation <3 months after discontinuation, or for lack of follow‐up. Cases were censored during follow‐up upon cerebral cavernous malformation resection/radiation or later statin reinitiation. Results Follow‐up included 33 patients who had been randomized to placebo and 32 who had taken atorvastatin. Four SH events occurred at 3, 49, 84, and 225 days after atorvastatin discontinuation, and 1 SH at 395 days after discontinuing placebo. There was significantly lower symptomatic hemorrhage‐free survival in the atorvastatin‐discontinuation group (log‐rank χ 2 =4.136, P =0.042). The hazard ratio was 0.162 (95% CI, 0.027–0.977) for placebo versus atorvastatin discontinuation. Conclusions Discontinuation of atorvastatin was associated with a higher risk of recurrent SH compared with placebo discontinuation. Additional studies are warranted to confirm this hypothesis‐generating observation, examine potential mechanisms, and how best to mitigate this risk. REGISTRATION URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02603328.
Abstract A041: Recurrent Symptomatic Hemorrhage after Discontinuation of Atorvastatin versus Placebo in Randomized Trial of Hemorrhagic Cerebral Cavernous Malformations
Ali, Bader , Lee, Justine J., Alcazar-Felix, Roberto, Stadnik, Agnieszka , Sader, Georgeio, Shenkar, Robert, Girard, R., Hanley, Daniel, Awad, Issam A, Alcazar‐Félix, Roberto J. , Shenkar, Robert , Flemming, Kelly D. , Girard, Romuald , Hanley, Daniel F. , Awad, Issam A.

Stroke | January 29, 2026 | Volume: 57 | Issue: Suppl_1 | Pages: No page available

10.1161/str.57.suppl_1.a041 Get It

Background: There is much interest in drug development to prevent rebleeding after symptomatic hemorrhage (SH) in cerebral cavernous malformations (CCM) and its neurologic sequelae. A recent randomized prospective controlled trial (AT CASH EPOC clinicaltrials.gov NCT02603328) demonstrated that atorvastatin for up to 2 years was safe but did not significantly alter CCM iron deposition or SH rates. However, the consequences of discontinuing atorvastatin in CCM patients remain unknown. Given reports of rebound effects with discontinuation of statins, we here hypothesize that SH recurs more frequently in hemorrhagic CCMs after discontinuation of atorvastatin than placebo. Methods: We conducted 12-month (±1 month) post-treatment follow-up of all 80 patients randomized in the AT CASH EPOC trial (41 atorvastatin, 39 placebo) to identify potential recurrent SH from the date of trial drug discontinuation. Every SH was adjudicated by review of imaging and corresponding symptoms. Patients were excluded for < 90% compliance with study drug or its discontinuation <3 months during the trial, and for lack of follow-up. Cases were censored during follow-up upon CCM resection/radiation or atorvastatin initiation/re-initiation. Results: Follow-up included 33 patients who had been randomized to placebo and 32 who had taken atorvastatin.During follow-up, 4 SH events occurred at 3, 49, 84, and 225 days after atorvastatin discontinuation, and only 1 SH 395 days after discontinuing placebo. Kaplan–Meier curves demonstrated significantly lower symptomatic hemorrhage-free survival in the atorvastatin-discontinuation group (log-rank chi=4.136, p=0.042). The Gehan–Breslow–Wilcoxon test (chi=4.080, p=0.043) highlighted early divergence in recurrent SH risk. The hazard ratio was 0.162 (95% CI 0.027–0.977) for placebo vs. atorvastatin discontinuation. Conclusion: While there was no difference in SH rates during 2 years of treatment with atorvastatin versus placebo in randomized clinical trial, discontinuation of atorvastatin was associated with a significantly higher and earlier risk of recurrent SH compared with placebo discontinuation. This raises concern for a rebound effect during the year after statin withdrawal in hemorrhagic CCM patients, potentially mediated by reactivation of Rho-associated kinase. Additional studies are warranted to confirm these observations and to assess whether statin tapering or maintenance therapy can mitigate the risk of discontinuation in hemorrhagic CCM.
Abstract TP375: Assessment of Functional Outcome in the AT CASH EPOC Trial of Hemorrhagic Cerebral Cavernous Malformations
Alcazar, Roberto, Sader, Georgeio, Stadnik, Agnieszka , Lee, Justine J., Shenkar, Robert, Treine, Kevin, McBee, Nichol , Girard, R., Thompson, Richard, Hanley, Daniel, Awad, Issam A, Alcazar‐Félix, Roberto J. , Shenkar, Robert , Girard, Romuald , Thompson, Richard E., Hanley, Daniel F. , Awad, Issam A. , Flemming, Kelly D.

Stroke | January 29, 2026 | Volume: 57 | Issue: Suppl_1 | Pages: No page available

10.1161/str.57.suppl_1.tp375 Get It

Introduction: Functional outcome scales are commonly used in neurological clinical trials. Prior studies suggested that these scales may reflect symptomatic hemorrhage (SH), but their performance in detecting treatment effects has not been assessed in clinical trials of cerebral cavernous malformations (CCM). And they have not been correlated with CCM bleeding as reflected by lesional iron content assessed by quantitative susceptibility mapping (QSM) MRI. Hypothesis: We hypothesized that functional outcome measures would detect differences between treatment arms in a randomized clinical trial of hemorrhagic CCM, and reflect new SH or a ≥6% increase in mean lesional QSM reflective of CCM bleeding. Methods: Eighty adults with CCM-related SH in the prior 12 months of enrollment were randomized 1:1 to atorvastatin 80 mg/day or placebo for 2 years. Functional outcomes, including mRS, EQ-5D index, EQ-VAS, and PROMIS-29 domains, were collected at baseline, Year 1, and Year 2. Analyses were conducted in 63 participants (32 atorvastatin, 31 placebo) in the modified intention-to-treat trial cohort who had contributed at least one paired annual clinical and imaging assessment. Results: No significant differences were found between atorvastatin and placebo groups in any functional outcome measure across timepoints. Rates of functional decline and improvement were comparable, except for PROMIS Fatigue which improved more in the atorvastatin than placebo patients from baseline to Year 1 (p=0.019). Pooled analyses showed that several functional domains had strong specificity for identifying SH. PROMIS Sleep Disturbance decline from baseline to Year 2 was associated with SH (p=0.0045; specificity 92.3%, sensitivity 57.1%). A ≥10-point drop in EQ-VAS from baseline to Year 1 identified all SH cases during that interval (p=0.007; sensitivity 100%, specificity 83.6%). Functional decline had low sensitivity in detecting CCM bleeding on QSM, though specificity was high (>75%) across domains. Conclusions: Atorvastatin did not influence functional change over 2 years by any measure. PROMIS Sleep Disturbance and EQ-VAS demonstrated high specificity, and in the case of EQ-VAS also a high sensitivity for identifying SH. Functional outcomes across domains also had high specificity for occult bleeding in CCMs as measured by QSM. Poor sensitivity and consistent improvements over time demonstrate the limitations of functional outcome measures as endpoints of drug effects on CCM bleeding.
Abstract TP368: Relevance of Lesion Volume as an Outcome in Cerebral Cavernous Malformation Drug Trial
Alcazar, Roberto, Thompson, Richard E., Stadnik, Agnieszka , Sader, Georgeio, Jhaveri, Aditya, Lee, Justine J., Shenkar, Robert, Girard, R., Carroll, Timothy, Hanley, Daniel F., Awad, Issam A., Alcazar‐Félix, Roberto J. , Jhaveri, Aditya , Shenkar, Robert , Flemming, Kelly D. , Girard, Romuald , Hanley, Daniel F. , Awad, Issam A.

Stroke | January 29, 2026 | Volume: 57 | Issue: Suppl_1 | Pages: No page available

10.1161/str.57.suppl_1.tp368 Get It

Background: It is not clear if changes in lesion volume might represent a clinically relevant and statistically advantageous outcome parameter in early phase trials of novel drugs aimed at preventing bleeding in cerebral cavernous malformations (CCM). Methods: We analyzed the modified intention to treat cohort (33 patients receiving atorvastatin and 31 placebo) who contributed at least one paired imaging biomarker in the recently completed double-blinded randomized controlled AT CASH EPOC trial (clinicaltrials.gov NCT02603328). We examined prospective changes in CCM lesion volume and correlated these with symptomatic hemorrhage (SH) events. We contemporaneously assessed changes in lesional iron content by quantitative susceptibility mapping (QSM) on MRI, and objective (mRS) and subjective (EQ-VAS) functional status. We also simulated sample sizes needed to detect potential effects of a drug on lesion volume. Results: There was excellent correlation between independently assessed maximum lesion diameter and CCM lesion volume (R 2 = 0.68, P<0.0001). The mean (SD) percentage change in lesion volume per year was +6 (65) and +18 (94) in atorvastatin and placebo patients, respectively (P= 0.43). All cases with SH had increases in lesion volume as well as increases in mean lesional iron content by QSM, and most had declines in functional status on mRS and EQ-VAS. But there were many cases with increases in lesion volume with improved functional status or decreased mean lesional QSM, and other cases with worsening in function or increased lesional QSM and decreased lesion volume. There were no significant correlations of changes in lesion volume with concomitant changes in mean lesional QSM, mRS or EQ-VAS (all R/R 2 <0.5 and Bonferroni corrected P>0.05), including in brainstem lesions analyzed separately. Sample size simulations indicate larger numbers of cases needed to demonstrate a drug effect on changes in lesion volume than those needed to detect an effect on QSM change with a=0.05 and b=0.8, and even larger samples to detect effects on the proportion of cases with increased or decreased lesion volume. Conclusion: Changes in lesion volume occur frequently in CCM lesions after recent SH, but do not correlate with measures of bleeding in the lesions, nor appear to reflect functional changes. And they are not statistically advantageous in comparison to QSM measures for detecting potential drug effects.
Relevance of Lesion Volume as an Outcome in Cerebral Cavernous Malformation Drug Trial: Exploratory Analyses in Atorvastatin Treatment of Cavernous Angiomas with Symptomatic Hemorrhage Exploratory Proof of Concept
Alcazar‐Félix, Roberto J. , Thompson, Richard E. , Stadnik, Agnieszka , Kinkade, Serena , Sader, Georgio , Jhaveri, Aditya , Iqbal, Javed , Polster, Sean P. , Shenkar, Robert , Awad, Issam A. , Polster, Sean P , Shenkar, Robert , Flemming, Kelly D , Girard, Romuald , Carroll, Timothy , Hanley, Daniel F , Alcazar-Felix, Roberto J , Jhaveri, Aditya , Lee, Justine C. , Flemming, Kelly D. , Girard, Romuald , Hanley, Daniel F.

Neurosurgery | October 21, 2025 | Volume: 98 | Issue: 6 | Pages: 1395-1401

10.1227/neu.0000000000003814 Get It

BACKGROUND AND OBJECTIVES: It is not clear whether changes in lesion volume might represent a clinically relevant and statistically advantageous outcome parameter in early phase trials aimed at preventing bleeding in cerebral cavernous malformations (CCM). METHODS: We examined prospective changes in CCM lesion volume in the double-blinded AT CASH EPOC trial (clinicaltrials.gov NCT02603328). We correlated these with symptomatic hemorrhage (SH) events, contemporaneously assessed changes in lesional iron content by quantitative susceptibility mapping (QSM) on MRI, and objective (modified Rankin Scale (mRS)) and subjective (Euro-QoL Visual Analog Scale [EQ-VAS]) functional status. We also simulated sample sizes needed to detect potential effects on lesion volume. RESULTS: There was excellent correlation between independently assessed maximum lesion diameter and CCM lesion volume (R 2 = 0.68, P < .0001). The mean (SD) percentage change in lesion volume per year was +6 (65) and +18 (94) in atorvastatin and placebo patients, respectively ( P = .43). All cases with SH had increases in lesion volume and increases in mean lesional iron content by QSM, and most had declines in functional status on mRS and EQ-VAS, but there were no overall meaningful correlations of changes in lesion volume with concomitant changes in mean lesional QSM, mRS, or EQ-VAS (all R/R 2 < 0.5 and Bonferroni corrected P > .05), including in brainstem lesions analyzed separately. Sample size simulations indicate larger case numbers needed to demonstrate an effect on change in lesion volume than those needed to detect an effect on QSM change with α = 0.05 and β = 0.8, and even larger samples to detect effects on the number of cases with increased or decreased lesion volume. CONCLUSION: Changes in lesion volume occur frequently in CCM lesions after recent SH, but do not correlate with biomarkers of lesional bleeding, nor reflect functional changes, and are not statistically advantageous compared with QSM measures in detecting potential drug effects.
Estimates of actual and potential lives saved in the United States from the use of COVID-19 convalescent plasma
Buras, Matthew R., Carter, Rickey E. , Joyner, Michael J. , Bloch, Evan M. , Henderson, Jeffrey P. , Senefeld, Jonathon W. , Wright, R. Scott , Carter, Rickey E , Joyner, Michael J , Henderson, Jeffrey P , Shoham, Shmuel , Sullivan, David J , Casadevall, Arturo , Senefeld, Jonathon W , Dragotakes, Quigly , Johnson, Patrick W. , Gebo, Kelly A , Hanley, Daniel F. , Pirofski, Liise‐anne , Shoham, Shmuel , Tobian, Aaron A.R. , Wiggins, Chad C. , Paneth, Nigel , Sullivan, David , Casadevall, Arturo

Proceedings of the National Academy of Sciences | October 1, 2024 | Volume: 121 | Issue: 41 | Pages: No page available

10.1073/pnas.2414957121 Get It

In the Spring of 2020, the United States of America (USA) deployed COVID-19 convalescent plasma (CCP) to treat hospitalized patients. Over 500,000 patients were treated with CCP during the first year of the pandemic. In this study, we estimated the number of actual inpatient lives saved by CCP treatment in the United States of America based on CCP weekly use, weekly national mortality data, and CCP mortality reduction data from meta-analyses of randomized controlled trials and real-world data. We also estimate the potential number of lives saved if CCP had been deployed for 100% of hospitalized patients or used in 15 to 75% of outpatients. Depending on the assumptions modeled in stratified analyses, we estimated that CCP saved between 16,476 and 66,296 lives. The CCP ideal use might have saved as many as 234,869 lives and prevented 1,136,133 hospitalizations. CCP deployment was a successful strategy for ameliorating the impact of the COVID-19 pandemic in the USA. This experience has important implications for convalescent plasma use in future infectious disease emergencies.
Outpatient COVID-19 convalescent plasma recipient antibody thresholds correlated to reduced hospitalizations within a randomized trial
Park, Han-Sol , Yin, Anna , Barranta, Caelan, Caputo, Christopher , Sachithanandham, Jaiprasath , Li, Maggie , Yoon, Steve, Sitaras, Ioannis , Jedlicka, Anne , Eby, Yolanda , Ram, Malathi , Fernández, Reinaldo E. , Baker, Owen R. , Fukuta, Yuriko , Patel, Bela , Heath, Sonya L. , Spivak, Emily S , Huamán, Moisés A. , Blair, Janis E. , Gerber, Jonathan M. , Petrini, Joann, Broderick, Patrick , Rausch, William, Cordisco, Marie Elena , Hammel, Jean, Greenblatt, Benjamin, Cluzet, Valerie , Cruser, Daniel, Oei, Kevin , Abinante, Matthew, Hammitt, Laura L. , Forthal, Donald N. , Cachay, Edward R. , Marshall, Christi E., Lane, Karen , McBee, Nichol , Gawad, Amy L., Karlen, Nicky, Singh, Atika, Jabs, Douglas A. , Shade, David , Lau, Bryan , Ehrhardt, Stephan , Baksh, Sheriza , Ou, Jiangda , Na, Yu Bin , Knoll, Maria Deloria , Ornelas-Gatdula, Elysse, Gniadek, Thomas J. , Wu, Jinke, Ndahiro, Nelson , Betenbaugh, Michael J. , Ziman, Alyssa , Bloch, Evan M. , Laeyendecker, Oliver , Ziman, Alyssa , Huaman, Moises A , Laeyendecker, Oliver , Lee, John S. , Shenoy, Aarthi , Mosnaim, Giselle S , Levine, Adam C , Meisenberg, Barry R. , Anjan, Shweta , Currier, Judith S. , Paxton, James H , Sutcliffe, Catherine G , Zand, Martin S. , Raval, Jay S. , Kassaye, Seble , Yarava, Anusha , Ford, Daniel E , Appel, Lawrence J. , Shapiro, Janna R. , Arroyo‐Currás, Netzahualcóyotl , Caturegli, Patrizio , Hanley, Daniel F. , Casadevall, Arturo , Shoham, Shmuel , Gebo, Kelly A , Tobian, Aaron A.R. , Pekosz, Andrew , Klein, Sabra L , Sullivan, David

JCI Insight | April 23, 2024 | Volume: 9 | Issue: 8 | Pages: No page available

10.1172/jci.insight.178460 Get It

BACKGROUND COVID-19 convalescent plasma (CCP) virus-specific antibody levels that translate into recipient posttransfusion antibody levels sufficient to prevent disease progression are not defined. METHODS This secondary analysis correlated donor and recipient antibody levels to hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double-blind, randomized clinical trial that compared CCP to control plasma. The majority of COVID-19 CCP arm hospitalizations (15/17, 88%) occurred in this unvaccinated, seronegative subgroup. A functional cutoff to delineate recipient high versus low posttransfusion antibody levels was established by 2 methods: (i) analyzing virus neutralization–equivalent anti–Spike receptor-binding domain immunoglobulin G (anti-S-RBD IgG) responses in donors or (ii) receiver operating characteristic (ROC) curve analysis. RESULTS SARS-CoV-2 anti–S-RBD IgG antibody was volume diluted 21.3-fold into posttransfusion seronegative recipients from matched donor units. Virus-specific antibody delivered was approximately 1.2 mg. The high-antibody recipients transfused early (symptom onset within 5 days) had no hospitalizations. A CCP-recipient analysis for antibody thresholds correlated to reduced hospitalizations found a statistical significant association between early transfusion and high antibodies versus all other CCP recipients (or control plasma), with antibody cutoffs established by both methods-donor-based virus neutralization cutoffs in posttransfusion recipients (0/85 [0%] versus 15/276 [5.6%]; P = 0.03) or ROC-based cutoff (0/94 [0%] versus 15/267 [5.4%]; P = 0.01). CONCLUSION In unvaccinated, seronegative CCP recipients, early transfusion of plasma units in the upper 30% of study donors’ antibody levels reduced outpatient hospitalizations. High antibody level plasma units, given early, should be reserved for therapeutic use. TRIAL REGISTRATION ClinicalTrials.gov NCT04373460. FUNDING Department of Defense (W911QY2090012); Defense Health Agency; Bloomberg Philanthropies; the State of Maryland; NIH (3R01AI152078-01S1, U24TR001609-S3, 1K23HL151826NIH); the Mental Wellness Foundation; the Moriah Fund; Octapharma; the Healthnetwork Foundation; the Shear Family Foundation; the NorthShore Research Institute; and the Rice Foundation.