Regulatory Comparisons For Starting First-In-Human Clinical Trials

Initiating human trials in the EU and UK has become an increasingly complex and resource-intensive undertaking, driven in part by recent changes to clinical trial application (CTA) preparation and submission requirements in the EU. At the same time, the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA) is in the midst of transitioning to a combined review process that is not yet fully implemented, contributing to longer and less predictable submission timelines. Because first-in-human (FIH) studies form the critical foundation for the entire trajectory of a drug development program, the results of these early safety evaluations directly influence downstream planning, regulatory strategy, and resource allocation.

Globally, health agencies are collaborating more closely than ever to promote innovation and ensure timely access to needed therapies. Reciprocal agreements between regulatory regions now support more efficient pathways for global drug development, with most agencies aligning to the technical principles established by the International Conference on Harmonisation (ICH). Despite this increasing convergence, meaningful regional differences remain, as each jurisdiction maintains distinct timelines and requirements for CTAs. Importantly, FIH trials conducted in Canada or the U.S. can often be used to support regulatory submissions in the EU and UK. Depending on your program, however, bridging studies or supplemental data may be required — making early consultation with Altasciences’ regulatory and clinical experts an essential step in planning a smooth, globally aligned development strategy.