Immunogenicity and Safety of a Novel MMR Vaccine (Live) (Freeze-dried): Results of a Phase II Clinical Trial

Introduction: This is the first study in Indian paediatric subjects to evaluate the novel Measles, Mumps and Rubella (MMR) vaccine developed by M/s Cadila Healthcare Limited, India, containing the Hoshino mumps strain. This phase II study was done as part of clinical development programme to evaluate the safety and immunogenicity of the novel vaccine in small cohort of target population before conducting the larger comparative phase III study. Aim: To evaluate the immunogenicity and safety of the single-dose and multi-dose formulations of the novel vaccine. Materials and Methods: One hundred and twenty three healthy children 15-18 months of age were administered a single dose of the novel MMR vaccine from either the single-dose or the multi-dose formulation. Immunogenicity of the vaccine was assessed by measuring IgG antibodies against the measles, mumps and rubella viruses before and six weeks after the vaccination. Safety of the vaccine was assessed by recording adverse events during the six week study period. Results: The seroconversion rate for anti-measles and anti-mumps antibodies was 100% while that for anti-rubella antibodies was 98.9% after the MMR vaccination. There was no difference in the seroconversion rates in the subjects receiving the MMR vaccine either from the single-dose or the multi-dose formulation. The Geometric Mean Titre (GMT) of anti-measles, anti-mumps and anti-rubella antibodies was 3154.0 mIU/mL, 90.6 EU/mL and 141.7 IU/mL, respectively. The vaccine was well tolerated, 28 subjects (out of 123) reported 43 adverse events during the study (adverse event rate of 21.8%). The most common adverse event reported during the study was fever in 19 subjects (15.4%) followed by rash and rhinorrhoea in five subjects (4.1%) each. Conclusion: The results of this phase II clinical trial show that both the single-dose and the multi-dose formulation of the novel MMR vaccine are immunogenic and well tolerated by healthy paediatric subjects aged 15-18 months.