A phase-3 trial conducted in Malawi, Africa, a region endemic to typhoid fever, has revealed that Bharat Biotech’s conjugate typhoid toxoid vaccine, Typbar, maintains efficacy for at least four years. This groundbreaking study marks the first randomized, controlled, double-blind trial aimed at assessing the long-term effectiveness of a single dose of the typhoid vaccine.
The trial, encompassing children aged nine months to 12 years, demonstrated the vaccine’s efficacy across all age groups studied. In total, 28,130 children participated, with half receiving Bharat Biotech’s typhoid vaccine and the other half a control vaccine. The results, published in The Lancet journal, showcased a significant reduction in typhoid fever cases among vaccinated children compared to the control group.
Over the 4.3 years of median follow-up, the efficacy of Bharat Biotech’s typhoid vaccine ranged from 70.6% to 79.3% across different age groups, demonstrating its effectiveness in preventing typhoid fever. Notably, the vaccine’s efficacy remained robust even after four years, with only a slight decline observed over time.
Furthermore, an ongoing immunogenicity study is assessing the efficacy of a booster dose administered approximately five years after the initial vaccination. This study aims to provide insights into the potential benefits of additional vaccine doses in maintaining long-term protection against typhoid.
The trial’s findings underscore the importance of Bharat Biotech’s conjugate typhoid vaccine in combating typhoid fever, particularly in endemic regions like Malawi. With the vaccine showing durable protection and minimal decline in efficacy over time, it holds promise for significantly reducing the burden of typhoid fever in vulnerable populations.
This research contributes valuable evidence supporting the high cost-effectiveness of typhoid vaccines and emphasizes the need for continued efforts in vaccine development and deployment to address global health challenges like typhoid fever.
