PHASE 1 SARS-COV-2-Spike-Ferritin-Nanoparticle (SpFN) Vaccine With ALFQ Adjuvant for Prevention of COVID-19

This clinical protocol outlines a first-in-human study of the safety, tolerability, and immunogenicity of different doses of SpFN\_1B-06-PL + ALFQ prophylactic vaccine against COVID-19 in healthy adults. The experimental vaccine in this study contains 2 parts: the vaccine (called SpFN\_1B-06-PL) and an experimental adjuvant called ALFQ. An adjuvant is a substance added to vaccines that can help to make the vaccine more effective by improving the immune response or causing the immune response to last longer. The experimental vaccine in this study does not contain the virus and cannot cause you to become infected with the COVID-19 disease. A total of 72 healthy adult participants (age range 18-55) will be enrolled in this study. Participants will be enrolled into one of three study arms: Arm 1: 25 µg of SpFN\_1B-06-PL vaccine with 0.5 mL ALFQ adjuvant in a total 1.0 mL injection volume (20 participants) or Placebo (4 participants) on Study Days 1, 29, and 181. Arm 2: 50 µg of SpFN\_1B-06-PL vaccine with 0.5 mL ALFQ adjuvant in a total 1.0 mL injection volume (20 participants) or Placebo (4 participants) on Study Days 1, 29, and 181. Arm 3: 50 µg of SpFN\_1B-06-PL vaccine with 0.5 mL ALFQ adjuvant in a total 1.0 mL injection volume (20 participants) or Placebo (4 participants) on Study Days 1 and 181. Participants will: * Be randomly assigned to get either the experimental COVID-19 vaccine or a placebo * Receive 2 or 3 vaccine or placebo injections in the same arm muscle * Record any side effects that they may experience for 7 days after receiving the injections. * Have blood, nose swabs, and saliva samples collected at each visit. * Have urine samples collected for pregnancy testing (females only). * Undergo medical and physical examinations. * Answer questions about potential exposures to COVID-19 in their daily life. The duration of this study will be for about 18 months.