Adaptive Clinical Trials Research Articles

Abstract PO-050: Precision Promise (PrP): An adaptive, multi-arm registration trial in metastatic pancreatic ductal adenocarcinoma (PDAC)

Abstract Background: Drug development in PDAC has been disappointing with an extremely low trial success rate despite considerable effort. PrP is a transformative, adaptive clinical trial platform that attempts to correct this by continuously and rapidly evaluating novel therapeutic options while maximizing the probability of patient (pt) randomization to an experimental treatment and nurturing enhanced cooperation among groups representing pt advocacy, pharmaceuticals, translational/clinical academia, and the FDA. This patient-centric study represents a fundamental shift in drug development for PDAC in the United States and aims to become the largest Phase 2/3 registrational study ever launched in this disease. Methods: PrP (NCT04229004) is a clinical trial platform sponsored by the Pancreatic Cancer Action Network (PanCAN) and funded solely through non-government sources. The protocol was finalized based on the FDA 2020 guidance document regarding "complex innovative designs" in registration trials https://www.fda.gov/media/130897/download. It utilizes adaptive randomization along with several trial design and Bayesian statistical innovations provided by Berry Consultants LLC. All pts undergo pre-and on-treatment biopsies with state-of-the-art genomic, transcriptomic, and immune analysis, along with collection of blood samples for research purposes throughout the study. Pts are managed using novel standardized supportive care techniques, and PrP contains 3 sub-protocols involving quality of life, sarcopenia and actigraphy. PrP was launched in 2020, and currently includes 20 US sites. Focused on both 1st and 2nd line treatment of metastatic PDAC, PrP uses an adaptive platform design with 30% of pts randomized between one of the 2 standard of care control arms (gemcitabine + nab-paclitaxel and mFOLFIRINOX) and 70% to experimental arms, currently either SM-88, a cancer metabolism-based agent (Tyme Inc); or Pamrevlumab, an antibody inhibiting the activity of the connective tissue growth factor (Fibrogen Inc.) The study is ongoing with >100 pts enrolled to date. The Data and Safety Monitoring Committee regularly reviews the data and continues to recommend that the trial proceeds as planned. New study arms will be added after review by an Arm Selection Committee that assesses the validity of the treatment target and the adequacy of the preexisting pre-clinical and clinical data. An additional experimental arm is anticipated in 2021. Conclusion: Compared to traditional trial designs, PrP offers several advantages: multiple investigational treatments can be evaluated in parallel over time; only ~ 175 pts per experimental arm required to initiate a regulatory registration; and increased learning from every patient during the trial, altogether resulting in both time saving and a 30-50% cost saving. In effect, PrP has created an entirely new “learning community” and can substantially accelerate drug development for PDAC. Citation Format: Vincent J. Picozzi, Anne-Marie Duliege, Anirban Maitra, Manuel Hidalgo, Andrew Eugene Hendifar, Gregory L. Beatty, Sudheer Doss Doss, Regina Deck, Lynn M. Matrisian, Julie Fleshman, Diane M. Simeone. Precision Promise (PrP): An adaptive, multi-arm registration trial in metastatic pancreatic ductal adenocarcinoma (PDAC) [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2021 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2021;81(22 Suppl):Abstract nr PO-050.

The design of a Bayesian adaptive clinical trial of tranexamic acid in severely injured children

BackgroundTrauma is the leading cause of death and disability in children in the USA. Tranexamic acid (TXA) reduces the blood transfusion requirements in adults and children during surgery. Several studies have evaluated TXA in adults with hemorrhagic trauma, but no randomized controlled trials have occurred in children with trauma. We propose a Bayesian adaptive clinical trial to investigate TXA in children with brain and/or torso hemorrhagic trauma.Methods/designWe designed a double-blind, Bayesian adaptive clinical trial that will enroll up to 2000 patients. We extend the traditional Emax dose-response model to incorporate a hierarchical structure so multiple doses of TXA can be evaluated in different injury populations (isolated head injury, isolated torso injury, or both head and torso injury). Up to 3 doses of TXA (15 mg/kg, 30 mg/kg, and 45 mg/kg bolus doses) will be compared to placebo. Equal allocation between placebo, 15 mg/kg, and 30 mg/kg will be used for an initial period within each injury group. Depending on the dose-response curve, the 45 mg/kg arm may open in an injury group if there is a trend towards increasing efficacy based on the observed relationship using the data from the lower doses. Response-adaptive randomization allows each injury group to differ in allocation proportions of TXA so an optimal dose can be identified for each injury group. Frequent interim stopping periods are included to evaluate efficacy and futility. The statistical design is evaluated through extensive simulations to determine the operating characteristics in several plausible scenarios. This trial achieves adequate power in each injury group.DiscussionThis trial design evaluating TXA in pediatric hemorrhagic trauma allows for three separate injury populations to be analyzed and compared within a single study framework. Individual conclusions regarding optimal dosing of TXA can be made within each injury group. Identifying the optimal dose of TXA, if any, for various injury types in childhood may reduce death and disability.

A Markov decision process for response adaptive designs

The randomized treatment allocation process in a response adaptive clinical trial is formulated as a stochastic sequential decision problem and an algorithm is proposed to approximate the optimal value under the average reward criterion. When the information of previous treatment allocations and associated responses are summarized with sufficient statistics for unknown parameters, the decision process becomes a Markov process, on which a span-contractor operator is defined. It is proven that the average reward under the policy identified from the span-contractor operator converges almost surely to the optimal value. Numerical results reveal that the sequential procedure based on the controlled Markov process shows superior ethical advantage and at the same time produces good statistical power for large sample sizes such as 200 or larger.

Costs and staffing resource requirements for adaptive clinical trials: quantitative and qualitative results from the Costing Adaptive Trials project

BackgroundAdaptive designs offer great promise in improving the efficiency and patient-benefit of clinical trials. An important barrier to further increased use is a lack of understanding about which additional resources are required to conduct a high-quality adaptive clinical trial, compared to a traditional fixed design.The Costing Adaptive Trials (CAT) project investigated which additional resources may be required to support adaptive trials.MethodsWe conducted a mock costing exercise amongst seven Clinical Trials Units (CTUs) in the UK. Five scenarios were developed, derived from funded clinical trials, where a non-adaptive version and an adaptive version were described. Each scenario represented a different type of adaptive design.CTU staff were asked to provide the costs and staff time they estimated would be needed to support the trial, categorised into specified areas (e.g. statistics, data management, trial management). This was calculated separately for the non-adaptive and adaptive version of the trial, allowing paired comparisons.Interviews with 10 CTU staff who had completed the costing exercise were conducted by qualitative researchers to explore reasons for similarities and differences.ResultsEstimated resources associated with conducting an adaptive trial were always (moderately) higher than for the non-adaptive equivalent. The median increase was between 2 and 4% for all scenarios, except for sample size re-estimation which was 26.5% (as the adaptive design could lead to a lengthened study period). The highest increase was for statistical staff, with lower increases for data management and trial management staff.The percentage increase in resources varied across different CTUs. The interviews identified possible explanations for differences, including (1) experience in adaptive trials, (2) the complexity of the non-adaptive and adaptive design, and (3) the extent of non-trial specific core infrastructure funding the CTU had.ConclusionsThis work sheds light on additional resources required to adequately support a high-quality adaptive trial. The percentage increase in costs for supporting an adaptive trial was generally modest and should not be a barrier to adaptive designs being cost-effective to use in practice.Informed by the results of this research, guidance for investigators and funders will be developed on appropriately resourcing adaptive trials.

Quo Vadis, COVID-19?

Quo Vadis, COVID-19?

Changes in Ventricular and Cortical Volumes following Shunt Placement in Patients with Idiopathic Normal Pressure Hydrocephalus.

While changes in ventricular and extraventricular CSF spaces have been studied following shunt placement in patients with idiopathic normal pressure hydrocephalus, regional changes in cortical volumes have not. These changes are important to better inform disease pathophysiology and evaluation for copathology. The purpose of this work is to investigate changes in ventricular and cortical volumes in patients with idiopathic normal pressure hydrocephalus following ventriculoperitoneal shunt placement. This is a retrospective cohort study of patients with idiopathic normal pressure hydrocephalus who underwent 3D T1-weighted MR imaging before and after ventriculoperitoneal shunt placement. Images were analyzed using tensor-based morphometry with symmetric normalization to determine the percentage change in ventricular and regional cortical volumes. Ventricular volume changes were assessed using the Wilcoxon signed rank test, and cortical volume changes, using a linear mixed-effects model (P < .05). The study included 22 patients (5 women/17 men; mean age, 73 [SD, 6] years). Ventricular volume decreased after shunt placement with a mean change of -15.4% (P < .001). Measured cortical volume across all participants and cortical ROIs showed a mean percentage increase of 1.4% (P < .001). ROIs near the vertex showed the greatest percentage increase in volume after shunt placement, with smaller decreases in volume in the medial temporal lobes. Overall, cortical volumes mildly increased after shunt placement in patients with idiopathic normal pressure hydrocephalus with the greatest increases in regions near the vertex, indicating postshunt decompression of the cortex and sulci. Ventricular volumes showed an expected decrease after shunt placement.

Incorporating covariates information in adaptive clinical trials for precision medicine

Precision medicine is the systematic use of information that pertains to an individual patient to select or optimize that patient's preventative and therapeutic care. Recent studies have classified biomarkers into predictive and prognostic biomarkers based on their roles in clinical studies. To design a clinical trial for precision medicine, predictive biomarkers and prognostic biomarkers should both be included. In statistical analysis, biomarkers are mathematically treated as covariates. We first classify covariates into predictive and prognostic covariates according to their roles. We then provide a brief review of recent advances in adaptive designs that incorporate covariates. However, the literature includes no designs that incorporate both prognostic covariates and predictive covariates simultaneously. In this paper, we propose a new family of covariate-adjusted response-adaptive (CARA) designs that incorporate both prognostic and predictive covariates and the responses. It is important to note that the predictive biomarkers and prognostic biomarkers play different roles in the new designs. The advantages of the proposed methods are demonstrated via numerical studies, and some further statistical issues are also discussed.

Non-static framework for understanding adaptive designs: an ethical justification in paediatric trials

Many drugs used in paediatric medicine are off-label. There is a rising call for the use of adaptive clinical trial designs (ADs) in responding to the need for safe and...

An ethically-motivated, Bayesian, adaptive design clinical trial bringing hope to women with menorrhagia…and warmth to statisticians' hearts.

An ethically-motivated, Bayesian, adaptive design clinical trial bringing hope to women with menorrhagia…and warmth to statisticians' hearts.

The Yin and the Yang of Transformative Research During the COVID-19 Pandemic-A Perspective.

The COVID-19 pandemic has highlighted the necessity for scientists from diverse disciplines to collaboratively mitigate the singular calamity facing humanity this century. The ability of researchers to combine exponential advances in technology and scientific acumen has resulted in landmark discoveries in pediatric research and is surmounting the COVID-19 challenge. Several of these discoveries exist in a realm of research that is not classically “basic” or “clinical.” Translational research characterizes this domain partially, but does not fully capture the integrated research approaches that have spurred these discoveries. Herein, we share our perspective on the common themes underpinning the basic and clinical research. We also highlight major differences in the scope, emphasis, approach, and limitations of basic and clinical research that impede multi-disciplinary approaches that facilitate truly transformative research. These differences in research thinking and methodology are ingrained during training wherein the limitations of the chosen discipline, and strengths of alternate disciplines are not adequately explored. Insular approaches are particularly limited in impacting complex diseases pathophysiology in the era of precision medicine. We propose that integration of -omics technologies, systems biology, adaptive clinical trial designs, humanized animal models, and precision pre-clinical model systems must be incorporated into research training of future scientists. Several initiatives from the NIH and other institutions are facilitating such broad-based “research without frontiers” training that paves the way for seamless, multi-disciplinary, research. Such efforts become “transformative” when scientific challenges are tackled in partnership with a willingness to share ideas, tackle challenges, and develop tools/models from the very beginning.

MO840ADAPTIVE DESIGN METHODS IN DIALYSIS CLINICAL TRIALS – A SYSTEMATIC REVIEW

Abstract Background and Aims Adaptive design methods are intended to improve efficiency of clinical trials, and relevant to evaluating interventions in dialysis populations. We sought to quantify the use of adaptive design clinical trials in dialysis. Method We completed a full text systematic review and adhered to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Our review utilised included a novel machine learning classifier and full text systematic review. We searched MEDLINE (Pubmed) and performed a detailed data extraction of trial characteristics and a narrative synthesis of the data. Results 50 studies, available as 66 articles, were included after full text review. 31 studies were conducted in a dialysis population and 23 studies had renal replacement therapy as a primary or secondary outcome. Group sequential designs were the most common type of adaptive design method used in dialysis randomized clinical trials and in general adaptive designs usage is increasing over time. Acute Kidney Injury (AKI) was studied in 27 (54%) of trials, End Stage Kidney Disease (ESKD) was studied in 22 (44%) of trials and Chronic Kidney Disease (CKD) was studied in one trial (2%). The most common country of lead author was the United States of America in n=20 (40%) of studies. 26 (52%) studies were supported by public funding. 41 studies (82%) did not report their adaptive design method in the title or abstract and would not be detected by a standard systematic review involving title and abstract searches. Conclusion Adaptive design methods are infrequently used in dialysis randomized control trials.

Ethical dimensions in randomized trials and off-label use of investigational drugs for COVID-19 treatment

Coronavirus disease 2019 (COVID-19) is a fast-developing viral pandemic spreading across the globe. Due to lack of availability of proven medicines against COVID-19, physicians have resorted to treatments through large trials of investigational drugs with poor evidence or those used for similar diseases. Large trials randomize 100–500+ patients at multiple hospitals in different countries to either receive these drugs or standard treatment. In order to expedite the process, some regulatory agencies had also given permission to use drugs approved for other diseases, despite a lack of evidence of efficacy in COVID-19. In this review, we highlight the potential ethical issues that should be addressed during the use of investigational drugs with little prior evidence as a treatment options during a pandemic. We discuss the impact of design of randomized clinical trials using LOTUS trial as an example and that of off-label use of drugs like chloroquine/hydroxychloroquine (CQ/HQ) on the safety of patients during COVID-19. We conclude that the adaptive randomized clinical trial designs offer a flexible and efficient approach, enabling patients to quickly switch to successful treatments, while minimizing the number of patients on standard of care. Randomized clinical trial design should consider blinding of investigators and only representative patients who can provide consent should be included. We also conclude the emergency approvals of drugs should be carefully issued and off-label use should be restricted in pandemics. Streamlined regulatory guidelines for emergency drug use in a pandemic can also help in providing benefit and minimizing harm to patients in the future.

Circulating Tumor DNA Reflects Uveal Melanoma Responses to Protein Kinase C Inhibition.

Simple SummaryUveal melanoma (UM) is a rare cancer, with no effective standard systemic therapy in the metastatic setting. Over 95% of UM harbor activating driver mutations that can be detected in the circulation. In this study, circulating tumor DNA (ctDNA) was measured in 17 metastatic UM patients treated with protein kinase C inhibitor (PKCi)-based therapy. ctDNA predicted response to targeted therapy and increasing UM ctDNA preceded radiological progression with a lead-time of 4–10 weeks. Next generation sequencing (NGS) of ctDNA also identified prognostic and treatment resistance mutations. Longitudinal ctDNA monitoring is useful for monitoring disease response and progression in metastatic UM and is a valuable addition to adaptive clinical trial design.The prognosis for patients with UM is poor, and recent clinical trials have failed to prolong overall survival (OS) of these patients. Over 95% of UM harbor activating driver mutations, and this allows for the investigation of ctDNA. In this study, we investigated the value of ctDNA for adaptive clinical trial design in metastatic UM. Longitudinal plasma samples were analyzed for ctDNA in 17 metastatic UM patients treated with PKCi-based therapy in a phase 1 clinical trial setting. Plasma ctDNA was assessed using digital droplet PCR (ddPCR) and a custom melanoma gene panel for targeted next generation sequencing (NGS). Baseline ctDNA strongly correlated with baseline lactate dehydrogenase (LDH) (p < 0.001) and baseline disease burden (p = 0.002). Early during treatment (EDT) ctDNA accurately predicted patients with clinical benefit to PKCi using receiver operator characteristic (ROC) curves (AUC 0.84, [95% confidence interval 0.65–1.0, p = 0.026]). Longitudinal ctDNA assessment was informative for establishing clinical benefit and detecting disease progression with 7/8 (88%) of patients showing a rise in ctDNA and targeted NGS of ctDNA revealed putative resistance mechanisms prior to radiological progression. The inclusion of longitudinal ctDNA monitoring in metastatic UM can advance adaptive clinical trial design.

Improving sample size recalculation in adaptive clinical trials by resampling.

Sample size calculations in clinical trials need to be based on profound parameter assumptions. Wrong parameter choices may lead to too small or too high sample sizes and can have severe ethical and economical consequences. Adaptive group sequential study designs are one solution to deal with planning uncertainties. Here, the sample size can be updated during an ongoing trial based on the observed interim effect. However, the observed interim effect is a random variable and thus does not necessarily correspond to the true effect. One way of dealing with the uncertainty related to this random variable is to include resampling elements in the recalculation strategy. In this paper, we focus on clinical trials with a normally distributed endpoint. We consider resampling of the observed interim test statistic and apply this principle to several established sample size recalculation approaches. The resulting recalculation rules are smoother than the original ones and thus the variability in sample size is lower. In particular, we found that some resampling approaches mimic a group sequential design. In general, incorporating resampling of the interim test statistic in existing sample size recalculation rules results in a substantial performance improvement with respect to a recently published conditional performance score.

Science, Medicine, and the Anesthesiologist

Science, Medicine, and the Anesthesiologist

Value of Adaptive Trials and Surrogate Endpoints for Clinical Decision-Making in Rare Cancers.

Despite high-level endorsement, the number of adaptive Phase II/III trials in rare cancers needs to be improved, with better understanding of their value for clinical decisions in daily practice. This paper describes approaches to trial design in rare cancers, which has been supplemented by a search of ClinicalTrials.gov for adaptive trial designs in rare cancer. In addition, an online survey of 3,200 oncologists was conducted. Practicing physicians were questioned on the importance of different evidence levels, types of adaptive trial design, and categories of surrogate endpoints for clinical decision making. The results of the online survey revealed that evidence from Phase II/III trials with an adaptive design and relatively small sample size was considered high value in rare cancer by 97% of responders, similar to the randomized controlled trial rating (82%). Surrogate clinical endpoints were considered valuable alternatives to overall survival by 80% of oncologists. Preferred adaptive designs were futility analysis, interim analysis, adaptive sample size, and adaptive randomization. In conclusion, rare cancer oncologists rate evidence from adaptive clinical trials with as high a value and importance for clinical decision making processes as conventional randomized controlled trials. All stakeholders have a vested interest in advances in clinical trial designs to ensure efficient and timely development of innovative medicinal products to allow more patients faster access to the pivotal treatment.

COVID-19, community trials, and inclusion

The COVID-19 pandemic has changed the research landscape with the emergence of platform trials. Platform trials are adaptive clinical trials in which patients with a single disease are randomly allocated to different treatments based on an algorithm to investigate whether various agents have clinical benefit.1 In The Lancet, the PRINCIPLE Trial Collaborative Group2 report no benefit of azithromycin compared with usual care (hazard ratio 1·08, 95% Bayesian credibility interval 0·95–1·23) for suspected COVID-19 in older adults in the community.

Disability Rating Scale in the First Few Weeks After a Severe Traumatic Brain Injury as a Predictor of 6-Month Functional Outcome.

An early acute marker of long-term neurological outcome would be useful to help guide clinical decision making and therapeutic effectiveness after severe traumatic brain injury (TBI). We investigated the utility of the Disability Rating Scale (DRS) as early as 1 wk after TBI as a predictor of favorable 6-mo Glasgow Outcome Scale extended (GOS-E). To determine the predictability of a favorable 6-mo GOS-E using the DRS measured during weeks 1 to 4 of injury. The study is a sub analysis of patients enrolled in the Epo Severe TBI Trial (n=200) to train and validate L1-regularized logistic regression models. DRS was collected at weeks 1 to 4 and GOS-E at 6 mo. The average area under the receiver operating characteristic curve was 0.82 for the model with baseline demographic and injury severity variables and week 1 DRS and increased to 0.88 when including weekly DRS until week 4. This study suggests that week 1 to 4 DRS may be predictors of favorable 6-mo outcome in severe TBI patients and thus useful both for clinical prognostication as well as surrogate endpoints for adaptive clinical trials.

Old drug, new Trick? The rationale for the treatment of COVID-19 with activated protein C

As the COVID-19 pandemic continues, researchers seek to identify efficacious treatments. Current approaches to COVID-19 therapeutics focus on antiviral agents, convalescent plasma, monoclonal antibodies, immunomodulators and more traditional therapies such as steroids [1-6]. Reversing disturbances in coagulation has also been identified as a priority area for candidate therapies, such as through the Accelerating COVID-19 Therapeutic Interventions and Vaccines 4 adaptive clinical trial (ACTIV-4) which is currently evaluating aspirin, heparins and apixaban [7]. Since there is a clear relationship between mechanisms of coagulation and the immune response, it is possible that reversing disturbances in coagulation may diminish the dysregulated immune response observed in COVID-19. The basis for this hypothesis is described below and is followed by discussion of a proposed candidate therapy - activated protein C. By treating COVID-19 patients using a novel approach, which does not focus on immune-based or antiviral treatments, but instead which addresses both the anti-thrombotic and inflammatory consequences of infection, the hope is that new therapeutic targets can be considered and new candidate therapies, such as activated protein C, may be evaluated.

Abstract PS11-08: Operational standardization and quality assurance yield high acceptance rate for breast MRI in the I-SPY 2 TRIAL

Abstract Background: The I-SPY 2 TRIAL is a multi-site response adaptive clinical trial evaluating novel drug combinations for neoadjuvant treatment of breast cancer. Patients receive four or more MRI studies during treatment, and serial measurement of functional tumor volume (FTV) is used to assess response. Under FDA IDE approval, FTV plays an integral role in adjusting patient randomization and evaluating treatment efficacy. FTV is a quantitative measure that requires stringent standards for image quality and protocol adherence. The I-SPY 2 TRIAL consistently reports a high level of data quality and data acceptance for FTV measurements. We present an overview of MRI operational performance and share lessons learned about maintaining high quality MRI data in a multi-site clinical trial. Methods: Over the 10-year course of the I-SPY 2 TRIAL, workflow has been improved to optimize communication between the Imaging Core Lab (ICL) and sites and to collect details about the MRI that are needed for accurate FTV measurement. A standardized imaging acquisition protocol is distributed to all sites, and new sites submit two test cases for review at site initiation. A scan verification form is required for each MRI study completed at sites to document critical information. Sites submit studies using TRIAD image transfer and de-identification software (American College of Radiology), and data is archived and processed at the ICL. All MRI studies are reviewed by the ICL for protocol adherence as soon as they are submitted, and feedback is provided to sites. Image quality factors including motion, fat suppression, and signal-to-noise ratio are qualitatively assessed. The ICL communicates with sites through a centralized email account, regular Coordinator Calls, and Imaging Working Group meetings to discuss emerging issues and offer ongoing training. The ICL contributes to revisions of study protocols and standard operating procedures. Results: As of June 2020, 3020 patients had been registered in I-SPY 2, 1741 patients randomized to treatment with one of 18 experimental drugs or standard therapy (controls), and a total of 7527 MRI studies were performed. FTV could be calculated for 97% (7317/7527) of MRI studies. Of the 7317 studies where FTV could be calculated, relatively minor issues with image quality or imaging protocol adherence were documented for 28% (2030/7317). These issues included motion artifacts (32%, 659/2030), off-protocol scan duration (21%, 433/2030), off-protocol contrast injection rate (14%, 281/2030), and off-protocol imaging field of view (9%, 191/2030). Conclusion: Breast MRI studies using a variety of scan protocols are well-suited for diagnostic evaluation, including BIRADS categorization, measurement of longest diameter, and assessment of lesion washout. The quantitative measures used in the I-SPY 2 trial require adherence to a specific imaging protocol that is kept consistent for all MRI studies for a single patient. Operational standardization, clear communication with sites, and streamlined workflow yield high quality MRI data across multiple sites and scanners. As a result, FTV is a robust biomarker of response to treatment, and is being used to predict patient response and guide treatment planning. We are actively investigating strategies that will improve FTV accuracy for predicting response and informing guidelines for treatment de-escalation. This will allow the ICL to further standardize and improve image quality and will provide the foundation for testing a variety of imaging biomarkers in the I-SPY 2 TRIAL. Citation Format: Jessica Gibbs, David C Newitt, Margarita Watkins, Wen Li, Lisa Cimino, Clifton Li, Natsuko Onishi, Lisa J Wilmes, Teffany Joy Bareng, Evelyn Proctor, Barbara LeStage, Bev Parker, the I-SPY 2 Coodinators, the I-SPY 2 Imaging Working Group, Nola M Hylton. Operational standardization and quality assurance yield high acceptance rate for breast MRI in the I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS11-08.