Long-Term Safety Analysis of the BBV152 Coronavirus Vaccine in Adolescents and Adults: Findings from a 1-Year Prospective Study in North India.

Abstract

Evidence on the long-term safety of COVID-19 vaccines is scarce. Here, in continuation of our previously published results on short-term safety, we provide data on the long-term safety of the BBV152 vaccine in adolescents and adults. This was a prospective observational study conducted from January 2022 to August 2023. Adolescents and adults receiving the BBV152 vaccine were interviewed telephonically about long-term adverse events of special interest (AESIs) after 1 year of vaccination. Risk factors of AESIs and AESIs persistent for at least 1 month were identified. Out of 1024 individuals enrolled, 635 adolescents and 291 adults could be contacted during the 1-year follow-up. Viral upper respiratory tract infections were reported by 304 (47.9%) adolescents and 124 (42.6%) adults in this period. New-onset skin and subcutaneous disorders (10.5%), general disorders (10.2%), and nervous system disorders (4.7%) were the common AESIs in adolescents. General disorders (8.9%), musculoskeletal disorders (5.8%), and nervous system disorders (5.5%) were the common AESIs in adults. Menstrual abnormalities were noticed in 4.6% of female participants. Ocular abnormalities and hypothyroidism were observed in 2.7% and 0.6% of participants, respectively. Among serious AESIs (1%), stroke and Guillain-Barre syndrome were identified in 0.3% and 0.1% of participants, respectively. Among adolescents, female individuals, those with a history of allergy and post-vaccination typhoid were respectively at 1.6, 2.8, and 2.8 times higher risk of AESIs. The majority of the AESIs persisted at the 1-year follow-up. Female individuals, adolescents with pre-vaccination COVID-19, those with co-morbidities, and those with post-vaccination typhoid had respectively 1.6, 2, 2.7, and 3.2 times higher odds of persistent AESIs. Adults with co-morbidities had more than 2 times higher odds of AESIs and persistent AESIs. The patterns of AESIs developing after BBV152 differed from those reported with other COVID-19 vaccines as well as between adolescents and adults. With the majority of AESIs persisting for a significant period, extended surveillance of COVID-19-vaccinated individuals is warranted to understand the course and outcomes of late-onset AESIs. Serious AESIs might not be uncommon and necessitate enhanced awareness and larger studies to understand the incidence of immune-mediated phenomena post-COVID-19 vaccination. The relationship of AESIs with sex, co-morbidities, pre-vaccination COVID-19, and non-COVID illnesses should be explored in future studies.