Safety of Russian-Backbone Trivalent, Live Attenuated Seasonal Influenza Vaccine in Healthy Subjects: Open-Label, Non-randomized Phase 4 Study.

INTRODUCTION AND AIM: A trivalent live attenuated influenza vaccine (Nasovac-S® ) was developed and licensed in India. A phase 4 study was conducted to assess safety.

METHODOLOGY: This non-randomized, open-label, single-arm study among individuals ≥ 2 years of age involved administration of 0.5 mL of Nasovac-S intranasally, with a 1-month follow-up after vaccination. Adverse events (AEs) were collected via structured diaries.

RESULTS: Among 500 vaccinated subjects, 160 were between 2 and 17 years of age, 240 were 18-49 years old and 100 were 50 years and older. A total of 533 solicited reactions were reported. The majority of these reactions were mild, and almost all of them resolved without any sequelae. A total of 20% of subjects reported at least one local solicited reaction, and 23% reported at least one systemic solicited reaction. None of the 45 unsolicited AEs reported by 37 subjects (7.4%) were causally related to the study vaccine.

CONCLUSIONS: The data from the study adds to the existing safety database of Nasovac-S.

REGISTRY: Clinical Trials Registry of India (CTRI/2015/08/006074).