Inclusion:
* Provide written informed consent prior to the initiation of any trial procedures.
* Able to understand and agrees to comply with all planned trial procedures and be available for all study visits.
* Male, or non-pregnant, non-breastfeeding female, age 18-55 years, inclusive, at time first study vaccination.
* Women of childbearing potential must agree to use or have practiced true abstinence or use at least one acceptable primary form of contraception.
* Women of childbearing potential must have a negative serum pregnancy test at screening and a negative urine pregnancy test within 24 hours prior to each study vaccination.
* Male participants must use acceptable contraception or be vasectomized and must refrain from donating sperm for 90 days following study vaccination.
* In good general health
* Reported receipt of a complete primary COVID-19 vaccine series and at least one booster with last vaccination at least 16 weeks prior to study product dose
* Clinical screening laboratory evaluations are within normal reference ranges or grade 1 with no clinical significance (NCS) per investigator discretion.
* Must agree to have samples stored for secondary research.
Exclusion:
* Positive SARS-CoV-2 PCR at screening.
* Abnormal vital signs (Grade 1 or higher) at screening.
* Body mass index (BMI) of \< 18 kilograms/square meter (kg/m\^2) or \> 35 kg/m\^2 (inclusive) at screening
* History of SARS-CoV-2 infection or receipt of any COVID-19 vaccine \< 16 weeks prior to study vaccination.
* Woman who is pregnant or breastfeeding.
* Blood or plasma donation within 4 weeks prior to study vaccination.
* Receipt of antibody or blood-derived products (except Rho D immunoglobulin) within 90 days prior to study vaccination.
* Any self-reported or medically documented significant medical or psychiatric disease or condition(s) that, in the opinion of the site Principal Investigator (PI) or appropriate sub-investigator, precludes study participation.
* Has an acute illness, as determined by the site PI or appropriate sub-investigator, within 72 hours prior to study vaccination.
* Has known human immunodeficiency virus, hepatitis B or hepatitis C infection at screening.
* Has a positive test result for hepatitis B surface antigen, hepatitis C virus antibody, or human immunodeficiency virus antigen or antibody at screening.
* Has an ongoing symptomatic condition for which there are ongoing medical investigations, but no diagnosis or treatment plan.
* Has any confirmed or suspected immunosuppressive or immunodeficient state such as asplenia, recurrent severe infections and chronic immunosuppressant medication within the past 6 months
* Has taken oral or parenteral (including intra-articular) corticosteroids of any dose within 30 days prior to the first study vaccination. Intranasal, ophthalmic, or topical (skin or eyes) corticosteroids are permitted.
* Has any significant disorder of coagulation requiring ongoing or intermittent treatment.
* Has participated in another investigational study involving any IP within 60 days, or 5 half-lives, whichever is longer, before the first vaccine administration.
* Has a history of hypersensitivity or severe allergic reaction (e.g., anaphylaxis, generalized urticaria, angioedema, other significant reaction) to any previous licensed or unlicensed vaccine or to the candidate vaccine components.
* Receipt of inactivated/subunit vaccine within 14 days prior to vaccine administration or live vaccine within 28 days prior to vaccine administration.
* Prior receipt of CovRBD-scNP-001
* Plan to receive a COVID-19 booster vaccine within the 209 days following the first study vaccination.
* Planned international travel in the period between vaccination through Study Day 57 visit.
* Has a history of alcohol or drug abuse within 3 years prior to study vaccination.
* Has any diagnosis, current or past, of schizophrenia, bipolar disease or other psychiatric diagnosis that may interfere with participant compliance or safety evaluations.
* Has been hospitalized for psychiatric illness, history of suicide attempt, or confinement for danger to self or others within 5 years prior to study vaccination.
* Has a history of receipt of an investigational ferritin-based vaccine.
* Has any abnormality or permanent body art (e.g., tattoo) that, in the opinion of the investigator, would obstruct the ability to observe local reactions at the injection site.
