Evaluating the Safety and Immunogenicity of Stabilized CH505 TF chTrimer in Healthy, HIV-uninfected Adult Participants.

Inclusion Criteria: * Able and willing to complete the informed consent process, including an Assessment of Understanding: volunteer demonstrates understanding of this study; completes a questionnaire prior to first vaccination with verbal demonstration of understanding of all questionnaire items answered incorrectly. * 18-55 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 vaccine administration. * Agrees not to enroll in another study of an investigational agent during participation in the trial. * In good general health according to the clinical judgement 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 as low risk for HIV acquisition per low risk guidelines (see protocol for more information), agrees to discuss HIV infection risks, agrees to risk reduction counseling, and agrees to avoid behavior associated with high risk of HIV exposure through the final study visit. Low risk may include persons stably taking PrEP (pre- exposure prophylaxis) as prescribed for 6 months or longer. * Hemoglobin \>12.5 mg/dL to 18 mg/dL * White blood cell (WBC) count \> 3,500/mm³ * Platelets ≥125,000 /mm³ * Alanine aminotr…