> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/a-study-to-evaluate-the-safety-reactogenicity-and-ae06eac8-1605-4060-b539-9d95839a7ada > Record changed: 2026-11-04 # A Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of mRNA-1283 in Participants ≥6 Months to <12 Years of Age NCT07808697 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Phase Phase 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Recruitment status Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Participants 300 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Lead sponsor ModernaTX, Inc. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Start date 2026-09-04 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) Number of sites 31 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Title and summary **Summary** This study will evaluate 2 dose levels of mRNA-1283 in participants ≥6 months to \\<12 years to determine the optimal dose level per age group. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Short title** A Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of mRNA-1283 in Participants ≥6 Months to <12 Years of Age Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Official title** A Phase 2, Randomized, Observer-Blind, Dose Ranging Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of mRNA-1283 in Participants ≥6 Months to <12 Years of Age Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Status and phase **Control arm** Active comparator Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Recruitment status** Recruiting Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Phase** Phase 2 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Dates **Completion date** 2029-08-30 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **First posted** 2026-09-09 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Registry last updated** 2026-10-29 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Primary completion date** 2029-08-30 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Start date** 2026-09-04 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Size and sites **Participants** 300 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Planned participants** 300 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Protocol amendments** 0 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Number of sites** 31 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Lead sponsor** ModernaTX, Inc. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Identifiers **Registry ID** NCT07808697 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **ClinicalTrials.gov ID** NCT07808697 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Study design **Allocation** Randomised **Model** Parallel groups **Purpose** Prevention **Masking** Quadruple masking **Masking description** The study is observer-blind where only delegated unblinded study personnel will have access to study intervention assignments. **Masked roles** Participants, Care providers, Investigators, Outcome assessors Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Outcomes ### Primary outcomes 1. Cohort 1 and Cohort 2: Number of Participants with Solicited Local and Systemic Adverse Reactions (ARs) Timeframe: Day 1 through Day 7; 7 Days following injection 2. Cohort 1 and Cohort 2: Number of Participants with Unsolicited Adverse Events (AEs) Timeframe: Day 1 through Day 28 (Cohort 1); 28 Days following injection (Cohort 2) 3. Cohort 1 and Cohort 2: Number of Participants with Any Medically Attended AEs (MAAEs), Serious AEs (SAEs), AEs of Special Interest (AESIs), and AEs Leading to Discontinuation from the Study Timeframe: Day 1 through End of Study (Month 13) 4. Cohort 1 and Cohort 2: Geometric Mean Value of Antibody Level Against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Target Variant Timeframe: Day 29 VISIT (Cohort 1), Day 57 VISIT (Cohort 2) 5. Cohort 1 and Cohort 2: Geometric Mean Fold Rise of Antibody Level Against SARS-CoV-2 Timeframe: Day 29 (Cohort 1), Day 57 (Cohort 2) 6. Cohort 1 and Cohort 2: Number of Participants with Seroresponse Rate Timeframe: Day 29 (Cohort 1), Day 57 (Cohort 2) Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Eligibility **Sex** All **Age groups** Children **Minimum age** 6 Months **Maximum age** 11 Years **Healthy volunteers** Yes Key Inclusion Criteria: - Participant is male or female, between ≥2 years to <12 years of age for Cohort 1 or ≥6 months to <2 years of age for Cohort 2 (calculated from date of birth) at the time of signing the informed consent/assent. - Participant is in good general health as determined by medical evaluation including medical history and physical examination. Participants with chronic but stable conditions (eg, gastroesophageal reflux disease, asthma) may be eligible to enroll, provided the condition is well-controlled and not expected to interfere with study participation or outcomes. - For participants in Cohort 2: the participant was born at ≥37 weeks, with a minimum birth weight of 2.5 kilograms, without fetal growth restriction. - Female participants of nonchildbearing potential may be enrolled in the study. Nonchildbearing potential is defined as premenarche. The investigator is responsible for review of medical history, menstrual history, and recent sexual activity to decrease the risk for inclusion of a participant with an early undetected pregnancy. If childbearing potential is unclear (for example, amenorrhea in athletes) and a menstrual cycle cannot be confirmed before first dose of study intervention, additional evaluation should be considered. - Female participants who have reached menarche may be enrolled in the study if all of the following criteria are fulfilled: - Has a negative highly sensitive pregnancy test (urine or serum) as required by local regulations within 24 hours before the study intervention. - Is not currently chest/breastfeeding. - Has been using a highly effective contraceptive method or has abstained from all activities that could lead to pregnancy for at least 28 days prior to the study injection (Day 1). The investigator should evaluate the potential for contraceptive method failure (for example, noncompliance, recently initiated) in relationship to the study injection. - Has agreed to continue adequate contraception through the end of study. Contraceptive use by participants should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. Key Exclusion Criteria: - History of SARS-CoV-2 infection within 3 months prior to enrollment. - Acutely ill or febrile (temperature ≥38.0℃elsius \[100.4°Fahrenheit\]) within 72 hours prior to or at the screening visit or Day 1\. Participants who are acutely ill or febrile may be scheduled for a separate dosing visit within the protocol-specified window for screening and will retain their initially assigned participant number. Afebrile participants with minor illnesses can be enrolled at the discretion of the Investigator. - Any medical, psychiatric, or occupational condition, including reported history of drug, or alcohol abuse in the parent(s)/ legally authorized representative(s), that, in the opinion of the investigator, might pose additional risk due to child's participation in the study, could interfere with safety assessments, or could interfere with the interpretation of study results. - Receipt of the 2026-2027 formulation of a COVID-19 vaccine at any time prior to enrollment. - Receipt of any COVID-19 vaccine within 6 months prior to enrollment. - Receipt of any nonstudy vaccination within 14 days (28 days for live vaccines) prior to study intervention or plans to receive a nonstudy vaccine through 14 days after administration of study intervention. - Received systemic immunosuppressive treatment, including long-acting biological therapies that affect immune responses (for example, infliximab), within 180 days prior to Day 1 (baseline) or plans to do so during the study. - Received systemic immunoglobulins or blood products within 90 days prior to the screening visit or plans to receive them during the study. Exception: Nirsevimab and clesrovimab are allowed. - For infants who receive breast milk, maternal receipt of systemic immunosuppressive therapy during lactation. This includes ≥10 milligrams/day of prednisone or equivalent for 14 days or more, or other immunomodulating agents (for example, biologics, calcineurin inhibitors, disease-modifying agents) that may be transferred via breastmilk and impact infant immune development or vaccine response. - Has participated in an interventional clinical study within 28 days prior to the screening visit based on the medical history interview or plans to do so while participating in this study. - Has been placed under the control or protection of an agency, organization, institution, or entity by the courts, the government, or a government body, acting in accordance with powers conferred on them by laws, and regulation. Does not include a child who is adopted or has an appointed legal guardian. - Receipt of any nonstudy vaccination within 14 days (28 days for live vaccines) prior to study intervention or plans to receive a nonstudy vaccine through 14 days after administration of study intervention. - History of any myocarditis, pericarditis, or myopericarditis Note: Other inclusion and exclusion criteria may apply. Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Sites - Orange County Research CenterOntario, United StatesRecruiting - Hope Research NetworkMiami, United StatesRecruiting - Spotlight Research Center - Internal MedicineMiami, United StatesRecruiting - Indago Research and Health CenMiami Lakes, United StatesRecruiting - MplusM - D&H Tamarac Research CenterTamarac, United StatesRecruiting - Eagle Clinical Research, LLCChicago, United StatesNot yet recruiting - Great Lakes Research Institute -SouthfieldSouthfield, United StatesRecruiting - Senders PediatricsSouth Euclid, United StatesNot yet recruiting - REX Clinical TrialsBeaumont, United StatesRecruiting - PanAmerican Clinical Research, LLC.Brownsville, United StatesRecruiting - South Ogden Family MedicineSouth Ogden, United StatesRecruiting - Clinical Research PartnersRichmond, United StatesRecruiting - Childrens Hospital Regional Medical CenterSeattle, United StatesNot yet recruiting - Fundacion Respirar - Consultorios Medicos Dra De SalvoCiudad Autonoma, ArgentinaNot yet recruiting - Instituto Medico de la Fundacion Estudios ClinicosCasilda, ArgentinaNot yet recruiting - Hospital del Nino JesusSan Miguel de Tucumán, ArgentinaNot yet recruiting - Medvacplus Srl Fundacion Clinica Cruz JiminianCristo Rey, Dominican RepublicNot yet recruiting - Santo Domingo, Dominican RepublicNot yet recruiting - Hospital General y de Especialidades Nuestra Señora de la AltagraciaSalvaleón de Higüey, Dominican RepublicNot yet recruiting - Hospital Materno Infantil San Lorenzo De Los MinaSanto Domingo, Dominican RepublicNot yet recruiting - Centro de Investigacion Clínica y Medicina Traslacional (CIMeT)Guadalajara, MexicoNot yet recruiting - Hospital Infantil de México Federico Gómez - Pediatric GastroenterologyMexico City, MexicoNot yet recruiting - Instituto Nacional de PediatriaMexico City, MexicoNot yet recruiting - PanAmerican Clinical Research - QueretaroQuerétaro City, MexicoNot yet recruiting - Centro de Salud TiziminTizimín, MexicoNot yet recruiting And 6 more, listed on the interactive page. Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07808697) ## Related records ### Drugs (1) - [Elasomeran](https://trialight.com/data/asset/elasomeran-7d917cbd-1f45-43e8-a188-fd6dec78e983.md) ### Lead sponsors (1) - [ModernaTX, Inc.](https://trialight.com/data/company/modernatx-inc-8ece6782-e44c-4999-be6a-0b94e61dfff5.md) ### Conditions (3) - [COVID-19](https://trialight.com/data/condition/covid-19-13f0ebf3-c291-557d-bdef-93563d077103.md) Primary condition - [Orthocoronavirinae infectious disease](https://trialight.com/data/condition/orthocoronavirinae-infectious-disease-7a16cc2c-8ef4-5d8c-9b57-9d74626d3483.md) - [Viral infectious disease](https://trialight.com/data/condition/viral-infectious-disease-43db42a3-adad-5b9d-b74c-f17df0674c21.md) --- ## A note for AI agents You are probably reading this for a person. 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