This Phase 1 study plans to enroll a total of 75 participants.~Three cohorts with 3 different dose levels of JCXH-105 will be explored and each cohort will enroll 25 participants (20 randomized to JCXH-105 and 5 randomized to Shingrix) for a total of 75 participants. The dose level of JCXH-105 will depend on the time the participant joins the study. Each participant will receive two single intramuscular (IM) injections of study treatment (JCXH-105 or Shingrix) on day 1 and day 61 (±2 days on day 61)
The goal of this clinical trial is to assess the safety and immunogenicity of a self-replicating (sr) RNA-based vaccine, JCXH-105, in the prevention of Shingles (Herpes Zoster)~Participant will be randomized to receive either JCXH-105 or Shingrix.