Comparative Immunogenicity and Safety of Measles-Mumps-Rubella Vaccine When Administered Using Needle Free Injection System to That with Conventional Needle-Syringe in India: A Randomized, Parallel Group Study.

Introduction: Pain due to injection and fear of needles is documented barriers to vaccination in children. Needle-Free Injection System ie N-FIS Methodology: This was a prospective, randomized, parallel group study (January-September 2024). Eligible participants 9-12 months of age were administered MMR vaccine 0.5 mL, subcutaneously using either N-FIS Results: A total of 60 infants with mean age of 10.5 months were enrolled in the study. At 28 day post dose 1 there was a significant and comparable rise in the MMR GMTs between the two groups. Similarly, at 28 day post vaccination, there was a significant rise in the proportions of seropositive subjects and the rates were comparable between the two groups (Measles: 100% vs 83%, p = 0.046; Mumps: 96.1% vs 95.8%, p = 0.999, Rubella: 92.3% vs 100%, p = 0.491). N-FIS was well tolerated and significantly lower number of subjects experienced pain (12% with N-FIS vs 33% with syringe). No serious or severe adverse events were reported. Conclusion: Administration of MMR vaccine using N-FIS induced robust and comparable immune responses to that observed with use of Needle-syringe and was well tolerated providing an alternative to paediatrician over conventional delivery system.