Anitua E, de la Fuente M, Muruzábal F, et al. - This study was undertaken to determine if plasma rich in growth factors (PRGFs) eye drops preserve their activity and biological properties after storage for 9 and 12 months at −20°C, and at 4°C, and at room temperature (RT) for 3 and 7 days in comparison to fresh samples (t0). From 6 healthy donors, PRGF eye drops were obtained and then they were stored at −20°C for 9 and 12 months. Without reducing the main growth factors and proteins and without any microbial contamination, PRGF eye drops can be stored for up to 12 months. In addition, after storage for 3 and 7 days at 4°C or at RT, the biological activity of the PRGF eye drops is maintained.