The webinar, held on February 3rd, 2026, delivered an in‑depth exploration of one of the most complex challenges in clinical research: designing and analysing trials for rare and ultra‑rare diseases.
The session examined innovative trial designs and advanced analytical approaches that had the potential to reshape evidence generation for these conditions. Discussions centred on raising awareness of emerging methodologies, fostering early and meaningful collaboration, identifying the persistent hurdles in rare disease trials, and working toward shared principles for interpreting ultra‑rare disease data.
A major focus of the event was single‑arm trials (SATs)—a design still widely used in rare disease research and occasionally accepted by regulators when treatment effects were substantial or when placebo use would have been unethical. Speakers reviewed regulatory and HTA views on SATs, analysed case studies where SATs succeeded and where they fell short, and unpacked the challenges they posed.
Another highlight was an exploration of how a real‑world evidence clinical trial could begin with a single patient and ultimately support a US FDA approval. The session also addressed evolving statistical methods and strategic approaches aimed at optimizing study designs and meeting the stringent evidence requirements for rare and ultra‑rare conditions.
Agenda
- Introduction – by Ralf-Dieter Hilgers, Professor at SFU and RealiseD coordinator
- Presentation – Do you want to stay single? Considerations on Single-Arm Trials in Drug Development by Yulia Dyachkova. In this presentation, we review regulatory and HTA positions on SATs; case studies in rare diseases where SATs could and could not address research questions, illustrating challenges posed when using SATs, evolving statistical methods and strategies to optimize study design to address evidence needs.
- Presentation – Real-World Evidence as a Trial Model for Rare Disorders by Guillaume Canaud. Starting from a single patient and ultimately leading to a US FDA approval, he will describe how they initiated a real-world evidence clinical trial. Through this approach, they were able to demonstrate both efficacy and safety.
- Discussion Pannel
- Juan Jose Abellan – Statistics and real-world evidence senior specialist at the European Medicines Agency
- François Houyez – Treatment Information and Access Director at Eurordis
- Angelika Geroldinger – Austrian Medicines and Medical Devices Agency (MEA)
- Yulia Dyachkova – Associate Director Biostatistician at Merck Healthcare
- Jenny Devenport – Global Head of Methods, Collaboration, & Outreach (MCO) at Roche
- Cornelia Dunger-Baldauf – Prime Force consultant at Novartis
- Lars Beckmann – Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG)
- Audience Q&A
- Closure
About RealiseD
RealiseD is an Innovative Health Initiative lead y Sigmund Freud Private University and AstraZeneca that unites nearly 40 partners from academia, regulatory bodies, clinical research institutes and hospitals, patient organisations, pharmaceutical companies or European Research Infrastructures to establish new gold standards for clinical trials in rare and ultra-rare diseases.
