The team from the Cochin-Pasteur Clinical Investigation Center of Vaccinology at Cochin AP-HP Hospital, Inserm and the University of Paris, coordinated by Prof. Odile Launay, carried out a systematic review of the literature on immunogenicity and efficacy of Covid-19 vaccines in immunocompromised individuals. It concluded that there is a risk of low immunogenicity of Covid-19 vaccines among immunocompromised people, particularly in solid organ transplant recipients and patients with malignant hemopathies.