MAJORITY OF VACCINES STUDIED IN PHASE 1-3 CLINICAL TRIALS ARE GRANTED A MARKETING AUTHORIZATION AND WILL BECOME TOOLS FOR PREVENTION OF INFECTIONS

Santtu Heinonen, Ulla E. Otava, Hilkka Liitsola, Samuli Salmi, Anna Seppä, Kirsi Udelius, Ilona Schmidt, Arto A. Palmu

Background: FVR – Finnish vaccine research is a research network focusing on vaccine research. The history of FVR since 2022 and its predecessor Tampere University Vaccine Research Center dates to 1997. In this study we reviewed the studies conducted by the FVR and its predecessors and estimate the proportion of the clinical vaccine trials leading to marketing authorization of the investigational medicinal product (IMP).

Methods: We reviewed our own databases and identified the IMP used in each trial. Then, public databases of European Medicines Agency (EMA) and U.S. Food and Drug Administration (FDA) were reviewed to define whether 1) the IMP had received a market authorization, 2) in which target population the authorization was granted and 3) whether the authorization was still valid in 2025.

Results: Since 1997, a total of 168 vaccine trials have been conducted. The clinical trials covered all development phases (1-4) with a majority of phase 3 trials (n=106/168; 62%). Trials were conducted in all age groups from infants to elderly with the largest proportion of pediatric studies (children 1-10 years of age; n=75/168; 44%). Of IMPs included in the phase 1-3 trials completed before 2023, 91/122 (75%) have currently a marketing authorization in the study population granted by EMA or FDA.

Conclusions: Majority of investigational vaccines in clinical trials conducted in Finland has resulted a marketing authorization. This highlights the importance of conducting clinical vaccine trials to enable use of new preventive tools to control communicable diseases. Also, it is reassuring for volunteers participating in clinical vaccine trials.