Medical Information Only. Always consult your healthcare provider before enrolling in any clinical trial.
NCT04785144 · ClinicalTrials.gov registry record · Phase 1
Safety and Immunogenicity Study of a SARS-CoV-2 (COVID-19) Variant Vaccine (mRNA-1273.351) in Naïve and Previously Vaccinated Adults
A Phase 1 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- Completed
- Registry status
- Phase 1
- Development phase
- 135
- Enrollment target
NCT04785144: Completed Phase 1 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
NCT04785144 is a Phase 1 study that has completed, run by National Institute of Allergy and Infectious Diseases (NIAID). The registered enrollment target is 135 participants, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (125% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04785144, a Phase 1 study, has completed, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 135 participants
- Enrollment target
Study Summary
This is a phase 1, open-label, randomized clinical trial in males and non-pregnant females, 18 years of age and older, who are in good health, have no known history of COVID-19 or SARS-CoV-2 infection, and meet all other eligibility criteria. This clinical trial is designed to assess the safety, reactogenicity and immunogenicity of mRNA-1273.351 manufactured by ModernaTX, Inc, given in vaccination schedules alone, sequentially, or coadministered with mRNA-1273. mRNA-1273.351 is a novel lipid nanoparticle (LNP)-encapsulated mRNA-based vaccine that encodes for a full-length, prefusion stabilized S protein of the SARS-CoV-2 B.1.351 variant. Enrollment will occur at approximately five domestic clinical research sites. This study includes two cohorts. Cohort 1 will provide rapid information about the immunogenicity of mRNA-1273.351 in a previously vaccinated group. This cohort can inform near term public health decisions if the variant virus becomes more widespread. Cohort 2 will evaluate different strategies for generation of cross protective immune responses in a naïve population. This cohort will take longer to provide information on the immunogenicity of mRNA-1273.351, but is important to inform future public health strategies. Cohort 1 will include approximately 60 subjects 18 years of age and older who received two vaccinations of mRNA-1273 at dosages of 50 mcg, 100 mcg, or 250 mcg in the Phase 1 clinical trial (DMID 20-0003). Subjects in Cohort 1 will receive a single intramuscular (IM) injection of the designated vaccine and will be followed through 12 months after vaccination. Follow-up visits will occur on Days 8, 15, and 29, as well as 3, 6, and 12 months after the vaccination. Cohort 2 will include approximately 150 participants 18 through 55 years of age who have not received a COVID-19 vaccine, have no known history of COVID-19 or SARS-CoV-2 infection, and do not have underlying conditions that are associated with an increased risk of severe illness from S
Primary Outcome
Number of participants that experienced MAAEs during the course of the study.
Interventions
- BIOLOGICAL mRNA-1273
- BIOLOGICAL mRNA-1273.351
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 135 participants |
| Start Date | 2021-03-31 |
| Est. Completion | 2022-07-05 |
| Phase | Phase 1 |
What the finished NCT04785144 record still lists
NCT04785144 is an interventional study that assigns participants to a tested intervention. The registered 135 participants enrollment target is mid-sized for trials with a published cap, above the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (125% higher).
The record links to 0 conditions, and to 2 interventions - of which mRNA-1273 is the first listed.
NCT04785144 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04785144 about?
NCT04785144 is a clinical study titled "Safety and Immunogenicity Study of a SARS-CoV-2 (COVID-19) Variant Vaccine (mRNA-1273.351) in Naïve and Previously Vaccinated Adults". This is a phase 1, open-label, randomized clinical trial in males and non-pregnant females, 18 years of age and older, who are in good health, have no known history of COVID-19 or SARS-CoV-2 infection, and meet all other eligibility criteria. This clinical trial is designed to assess the safety, rea...
What is the current status of trial NCT04785144?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 135 participants. The study started on 2021-03-31. Estimated completion is 2022-07-05.
What interventions are being tested in trial NCT04785144?
The interventions under investigation include: mRNA-1273 (BIOLOGICAL), mRNA-1273.351 (BIOLOGICAL).
Who is sponsoring clinical trial NCT04785144?
This trial is sponsored by National Institute of Allergy and Infectious Diseases (NIAID), which has 2,006 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04785144's enrollment target sits among peer trials
135 425th of 2000 higher than 1,574 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
Nationwide trials with similar profiles
Cross-condition peers matched on enrollment target and registry start date, not the same-condition list above.
Similar enrollment target
- NCT00870129 · 135 participants · NA
Magnetic Resonance (MR) Imaging to Determine High Risk Areas in Patients With Malignant Gliomas and to Design Potential Radiation Plans and to Examine Metabolite Changes in Gliomas and Other Solid Tumors
- NCT03666000 · 135 participants · Phase 1
Dose-escalation and Dose-expansion Study of Safety of Azer-cel (PBCAR0191) in Participants With Relapsed/Refractory (r/r) Non-Hodgkin Lymphoma (NHL) and r/r B-cell Acute Lymphoblastic Leukemia (B-ALL)
- NCT04891510 · 135 participants · NA
A Comparative Analysis of REVOLVE, LipoGrafter, and Viality in Autologous Fat Grafting During Breast Surgery
- NCT05121051 · 135 participants · Phase 2
Testing the Effect of the Broccoli Seed and Sprout Extract, Avmacol ES, on the Cancer Causing Substances of Tobacco in Heavy Smokers
Similar registry start date
- NCT05962346 · started 2026-12 · NA
Fetal Endoscopic Tracheal Occlusion for Congenital Diaphragmatic Hernia
- NCT07125183 · started 2026-12 · Phase 2
Study on Efficacy and Tolerability of Weekly Doxorubicin in Elderly Patients With Advanced or Metastatic Leiomyosarcoma
- NCT07292298 · started 2026-11 · Phase 2
Phase 2 Single-Arm Rectal Cancer Brachytherapy for Patients With Low-Lying Residual Adenocarcinoma After Total Neoadjuvant Therapy to Improve Organ Preservation Rates
- NCT04263285 · started 2026-10 · NA
Treatment of Depression Post-SCI