Clinical Trial to Evaluate the Safety and Immunogenicity of Ferritin Nanoparticles Expressing Native-like HIV-1 Envelope Trimers Followed by Boost With mRNA Lipid Nanoparticles Encoding a Native-like HIV-1 Envelope Trimer in Adults Without HIV

Inclusion Criteria: * Able and willing to complete the informed consent process, including an Assessment of Understanding (AoU): Volunteer demonstrates an understanding of this study and completes a questionnaire prior to first vaccination with verbal demonstration of understanding of questionnaire items that were answered incorrectly. * 18 to 55 years old, inclusive, on day of enrollment. * Available for clinic follow-up through the last clinic visit, willing to undergo lymph node fine needle aspiration and leukapheresis, and willing to be contacted 12 months after the last study-product administration. * Agrees not to enroll in another study of an investigational agent during participation in the trial. If a potential participant is already enrolled in another clinical trial, approvals from the other trial sponsor and the HVTN 307 PSRT are required prior to enrollment into HVTN 307. * In good general health according to the clinical judgment of the site investigator. * Physical examination and laboratory results without clinically significant findings that would interfere with assessment of safety or reactogenicity in the clinical judgement of the site investigator. * Assessed by clinical staff as having a low likelihood of acquiring HIV per guidelines, agrees to discuss their potential for HIV acquisition, agrees to risk-reduction counseling, and agrees to avoid behaviors associated with a higher likelihood of acquiring HIV through the final study visit. Low likelihood ma…