This study tests a new vaccine called CDC-9 Inactivated Rotavirus Vaccine (IRV) for healthy adults aged 18-45. Rotavirus can cause severe diarrhea, especially in low-income countries. This vaccine is given as a shot in the muscle (intramuscular, or IM) instead of by mouth and aims to be safer and more effective. Participants will receive three vaccine doses, each four weeks apart, and will be monitored for 6 months to check for safety, side effects, and immune response.

**Key Points:**

• Participants receive 3 shots over 57 days, with regular check-ups.
• Study lasts about 8 months, including follow-up visits.
• Participants must be healthy, not pregnant, and meet certain health criteria.

To join, you must be between 18-45 years old, in good health, and agree to all study visits and tests. Women must use birth control and have negative pregnancy tests. The study excludes those with certain health issues or who have had certain vaccines recently. Participants help improve vaccine options for rotavirus, potentially saving many lives.