PNEUMOCOCCAL VACCINE STUDY Osallistu tutkimukseen Research code: C4801002 EU trial number: 2023-505154-18-00 Vaccine Research Clinics: Espoo Clinic, Helsinki South Clinic, Järvenpää Clinic, Tampere Clinic, Turku Clinic, Seinäjoki Clinic, Kokkola Clinic, Oulu Clinic