dose-finding trial to evaluate the safety and immunogenicity of cytomegalovirus (cmv) vaccine mrna-1647 in healthy adults

Conditions: Cytomegalovirus Infection

Summary: this clinical study will assess the safety and immunogenicity of 3 dose levels of mrna-1647 cytomegalovirus vaccine in cmv-seronegative and cmv-seropositive healthy adults 18-40 years of age.

mrna-1647-p202 is a 2-part study. part 1 of the study evaluates the safety and immunogenicity of 3 dose levels of mrna-1647 vaccine or placebo, administered on a 0, 2, 6-month schedule in healthy cmv-seronegative and cmv-seropositive males and females, 18 to 40 years of age. a planned interim analysis of safety and immunogenicity through month 3 (1 month after the second dose) of part 1 of the study informed the selection of the middle dose level for further development. part 2 of the study is designed to further evaluate the safety and immunogenicity of the middle dose level of mrna-1647 vaccine or placebo on a 0, 2, 6-month schedule in approximately 200 healthy participants 18 to 40 years of age, comprised of cmv-seronegative and cmv-seropositive female population, which includes the target population for the pivotal phase 3 efficacy trial.

Eligibility criteria:
inclusion criteria: * male or female 18-40 years of age (part 1); female 18-40 years of age (part 2) * understands and agrees to comply with the trial procedures and provides written informed consent * according to the assessment of the investigator, is in good general health and is capable of complying with trial procedures * body mass index (bmi) 18-35 kilograms/meter (kg/m\^2) * female participants must either be of non-childbearing potential or use acceptable methods of contraception from at least 28 days prior to the first vaccination and through 3 months following last vaccination and is not breastfeeding. * male participants must agree to practice adequate contraception from the time of the first vaccination and through 3 months after the last vaccination. exclusion criteria: * acutely ill or febrile on the day of the first vaccination * prior receipt of any cmv vaccine * abnormal screening safety laboratory test results * diagnosis or condition that, in the judgment of investigator, is clinically unstable or may affect participant safety, assessment of safety endpoints, assessment of immune response, or adherence to trial procedures * has received or plans to receive a vaccine ≤28 days prior to the first vaccination or plans to receive a non-study vaccine within 28 days prior to or after any study vaccination, except for any licensed influenza vaccine which can be administered \>14 days before or after any study vaccination. covid-19 vaccines (regardless of manufacturer) may be administered \>7 days but preferably \>14 days before or after any study vaccination, with the intention of prioritizing covid-19 vaccination over all other considerations. * prior receipt of chronic systemic immunosuppressants or immune-modifying drugs * receipt of intravenous immunoglobulins or plasma products within 3 months prior to the day of the first study vaccination * previous receipt of medications in lipid nanoparticle (lnp) formulation (part 1 participants only) * has donated ≥450 milliliters (ml) of blood products within 28 days of the screening visit * participated in an interventional clinical trial within 28 days prior to the day of enrollment * is an immediate family member or household member of trial personnel

Keywords: moderna mrna-1647 cytomegalovirus cmv cytomegalovirus vaccine cytomegalovirus infections cytomegalovirus congenital virus diseases infection viral dna virus infections messenger rna