Skip to main content
External control arms

Trust scientific leadership and multi-disciplinary expertise to leverage external control arms

When an external control arm (ECA) becomes necessary, enhance your study feasibility, plan efficiently, and boost the chance of regulatory acceptance with proven ECA expertise and fit-for-purpose real-world data selection.

External Control Arms at ISPOR

ECA and real-world evidence expertise

central hub icon
80+ specialists providing guidance in the planning, design, and execution of ECAs for submission to FDA, EMA, and payers
find evidence quickly icon
Expertise across a wide range of RWD sources and applying a data-agnostic approach to select the most fit-for-purpose data sources
scientific team icon
Multi-disciplinary teams, including pharmaco-epidemiologists and biostatisticians, experienced across therapeutic areas

Developing ECAs for regulatory and HTA agencies

The effective use of ECAs remains a challenging proposition which requires significant expertise and experience to successfully navigate the data selection, design, analyses, and reporting required.

Why use an ECA?

To contextualize single-arm trial data (efficacy comparison, benchmark), when:

  • It is not feasible or ethical to use a placebo (recruitment challenges, etc).
  • Standard of care is likely to be updated over the course of the study.
  • Most commonly for rare disease and oncology therapeutic areas.

Which therapeutic areas are most relevant?

To contextualize single-arm trial data (efficacy comparison, benchmark), when:

  • ECAs are most commonly used for rare disease and oncology therapeutic areas.

You’ll find a collection of in-depth thought leadership resources on the topic of ECAs below, including a publications list showing examples of our ECA-related work across therapeutic areas, and our recent contribution to ISPOR’s Value & Outcomes Spotlight publication.

Looking for a partner to help you develop an ECA strategy and navigate their methodological complexity?

Informed by published guidelines and frameworks, our specialist teams offer a strong track record of scientific leadership in ECA design and execution, deep methodological expertise, and a data-agnostic approach that ensures the data we leverage is entirely fit-for-purpose.

Get in touch

Our approach

evidence generation icon

Feasibility and design

    • Planning and strategy support
    • Target Trial Philosophy
      -What would this trial have looked like if designed prospectively?
    • Feasibility assessment
      -Data source selection
      -Trial eligibility criteria
      -Sample size estimation
      -Endpoint identification and evaluation
      -Target estimand
    • Development of study protocol and statistical analysis plan
    • Evaluation of relevant literature
quality icon

Study execution

  • Multiple methods for estimating causal effect, including matching, weighting, TMLE, fine stratification, G-computation
  • Tailored approach to reduce bias and confounding based on feasibility
    -Sensitivity analyses to evaluate robustness of results against methodological decisions
    -Missing data methods
    -Multiplicity adjustments
  • Analytic documentation
  • Rigorous quality control
team icon

Communication

      • Result interpretation
      • Final study report
      • Submission support
      • Compliance with regulatory requirements
      • Publication strategy and execution (abstracts, posters, manuscripts)

Our leadership team

Our ECA leadership team reflects the deep experience and expertise we have in this field

Deb Casso

Deborah Casso

Vice President &
Head of Real-world Evidence

Deb has 30+ years of experience in the design and conduct of observational research studies, including 17 years partnering with pharmaceutical clients on the design, implementation, and strategic considerations of pharmacoepidemiology and drug safety studies and RWE for both pre- and post-approval regulatory decision-making (including ECAs). Deb holds an MPH in Epidemiology from the University of Washington and was trained at the Fred Hutchinson Cancer Research Center.

Craig Parzynski

Senior Director &
Head of Biostatistics

Craig has 18 years of experience in research conduct and 13 years of experience in the field of statistics. He is an expert in causal inference methods with a focus on external control arms, having conducted or consulted on more than 15 external control arm studies. He has contributed to over 40 peer-reviewed journal articles across many fields and therapeutic areas.  Prior to Genesis Research Group, he spent over 9 years as a statistician at Yale Center for Outcomes Research and Evaluation.

Image of Allie Sosinsky

Alexandra Sosinsky

Director of
Pharmacoepidemiology & Safety

Allie is a pharmacoepidemiologist who has led numerous label expansion, external comparator arm, natural history, post-marketing, post-authorization safety, and meta-analytic studies, many of which have been submitted to regulatory agencies/HTA bodies and successfully supported authorisation and reimbursement. She has 12 years of experience, authored 20+ peer-reviewed publications, and received her ScM in Epidemiology and Maternal Child Health from the Harvard T.H. Chan School of Public Health.

Resources

Developing Fit-for-Purpose External Control Arms to Optimize Submissions to Regulatory and Health Technology Assessment Agencies. Presented at ISPOR 2023.

Ask a question or request slides

Read our external control arm contribution to the July/August issue of ISPOR’s Value & Outcomes Spotlight

The Role of External Control Arms in Drug Development and Considerations for Success by Alexandra Z. Sosinsky, Craig S. Parzynski, and Deborah Casso

View article online
ECA case study

Effectiveness of tisagenlecleucel versus real-world standard of care in r/r FL with EMA review

To contextualize effectiveness of tisagenlecleucel, an autologous anti-CD19 CAR-T cell therapy, against physician’s choice standard of care in relapsed/refractory follicular lymphoma, to support a submission to the European Medical Association (EMA) requesting a Type II variation to the marketing authorization.

Genesis Research Group developed and executed an external control arm study for submission to the EMA. It was accepted as supportive evidence and the EMA ultimately approved the Type II variation to the marketing authorization in question.

Download full case study

Fit-for-purpose matchmaking: a data selection and RWE approach for both regulatory and HTA audiences

In spring 2024, we produced a webinar referencing external control arms and our approach to data selection. Participants included Allie Sosinsky, Director, Pharmacoepidemiology and Safety at Genesis Research Group, and Carole Longson MBE, Professor and Independent Senior Advisor.

Ask a question or request slides

Selected ECA-related publications

Our team members have co-authored over 1000 publications. View our ECA-related publications below.

TitleGR Author(s)YearTherapeutic AreaData SourceJournal/ConferenceLink
An Externally Controlled Trial to Indirectly Compare Tazemetostat Plus Lenalidomide and Rituximab Versus Lenalidomide and Rituximab after at Least One Prior Systemic Therapy in Patients with Refractory and Relapsed Follicular Lymphoma.Sosinsky A, Crowley A, Lieb C2023OncologySymphony/FHRDBloodView
External Control Analysis of Overall Survival in BRAF V600 Mutated Metastatic NSCLC: Comparing Single-Arm Dabrafenib + Trametinib Clinical Trial Outcomes with Real-World Standards of CareKanakamedala H, Wu WH2020NSCLCFlatironValue in HealthView
Comparison of clinical outcomes of patients with METΔex14 NSCLC treated with first-line capmatinib in the GEOMETRY mono-1 study with those of a cohort of real-world patientsKanakamedala H, Wu WH2020OncologyFlatironAnnals of OncologyView
Utilization of External Control Arm to Contextualize Clinical Efficacy of Tisagenlecleucel Treated Among Patients with Relapsed/Refractory Follicular Lymphoma from the Single-Arm Elara Trial Wei-Chun Hsu, Parzynski C, Rhodes R, Wen-Hsing Wu2021Oncologyn/aBloodView
Comparison of Clinical Outcomes Among Patients with Relapsed/Refractory Follicular Lymphoma Treated with Tisagenlecleucel in the Elara Trial Versus a Real-World External Control Arm of Patients Treated with Standard of Care Wei-Chun Hsu, Parzynski C, Rhodes R, Wen-Hsing Wu2021OncologyFHRDBloodView
Effectiveness of Alpelisib + Fulvestrant Compared with Real-World Standard Treatment Among Patients With HR+, HER2–, PIK3CA-Mutated Advanced Breast CancerKanakamedala H, Wei-Chun Hsu2021OncologyCGDBThe OncologistView
View additional non-ECA publications

Headquarters:

HOBOKEN
111 River Street, Suite 1120
Hoboken, New Jersey 07030, US