The main purpose of study is to evaluate the safety and immunogenicity of different dose levels of mRNA-1647 versus control in healthy cytomegalovirus (CMV)-seronegative and CMV-seropositive female and male participants 9 to 15 years of age. In addition, mRNA-1647 will be evaluated in female participants 16 to 25 years as a comparator cohort.
Phase 1 trials primarily test safety and dosing in a small number of participants (typically 20–100). Results do not yet speak to efficacy. FDA approval is typically many years away from this stage.
Phase 2 trials begin testing efficacy in a larger patient group (100–300). This is often where biotech binary events occur — positive Phase 2 data can significantly advance a company's pipeline narrative, while failures can be terminal for a program.
Enrollment is complete. The trial is in its follow-up or data collection phase — a readout may occur on or near the primary completion date.
Moderna Inc (MRNA) is the sponsoring company for this trial. BiotechSign currently grades this company C (64/100) based on composite catalyst signals across its full pipeline. This trial is one data point in that overall catalyst picture.