Clinical Trial to Evaluate the Safety and Immunogenicity of the COVID-19 Vaccine

This is a prospective, interventional, randomized, Phase I trial comparing two different dose levels and immunization regimen of a novel COVID-19 vaccine candidate (TMV-083/V-591) against SARS-CoV-2 infection, consisting of two phases, an unblinded dose escalation and a double-blind treatment phase, to assess the safety, tolerability and immunogenicity. 90 subjects will be enrolled, 30 per cohort in three cohorts, each cohort comprising 24 vaccinees and 6 placebo recipients. Subjects will either receive two immunizations with a low dosage vaccine (Cohort A), two immunization with a high dosage vaccine (Cohort B), a single immunization with the high dosage vaccine (Cohort C) or placebo (randomized to all three cohorts). As safety precaution, the study will begin with the enrolment of a small group of 6 sentinel subjects (2 Sentinel Groups, three subjects each of cohorts A and B) each of whom will receive the vaccine on days 0 and 28 in an unblinded and non-randomized manner. Thereafter, 84 remaining participants will be enrolled in a double-blinded, randomized manner into one of the three cohorts (A, B or C). Placebo will be applied to blind the different regimen. After the screening visit, participants will be expected to return to the investigational clinical site for 8 visits (9 for the sentinel groups) up to day 91 for immunogenicity sample collection and up to day 210 for safety assessments. Samples for measles shedding will be collected from subjects of the Sentinel Groups (unblinded regiment in cohort A and B). Body fluids including saliva, nasal swab, urine and whole blood will be collected from day 0 up to day 42. The investigator and site personnel assessing Adverse Events (AEs), all participants, as well as the sponsor's representatives involved in the monitoring and conduct of the study will be unblinded to which vaccine was administered within the unblinded treatment phase. Only the site personnel performing randomization, preparation and administration of Investigational Medicinal Product (IMP) will be unblinded within the randomized double-blinded treatment phase.